Biology-Chemistry-Pharmacology Institute of Biology Freie ...userpage.fu-berlin.de/~biolehre/docs/bioen.pdf · Biology-Chemistry-Pharmacology Most scientific progress nowadays is

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Department of Biology-Chemistry-Pharmacology

Institute of Biology

BroschüreBioEnglisch 26.02.2001 12:15 Uhr Seite 1

Contents

Department of Biology-Chemistry-Pharmacology6

Biology in Berlin 7

Structure of the institute 8

From our research 11

NeurobiologyGeneticsProtozoaChemical ecologyNeuroanatomy Behavioural biology Extremophile red algae Molecular adaptation Molecular photo-physiologyCryoprotectinMetabolic paths Ecotoxicology

Botanic Garden and Botanical Museum 25

Studying at the institute 26

Biology in brief 27

Where to find us 30

Impressum

Published byThe Presidency of the Freie Universität BerlinPress and Information Office Felicitas von [email protected]/presse

Edited byInstitute of BiologyCatarina Pietschmann Translation: Richard HolmesDecember 2000

Typesetting & layout uni[:com] werbeagentur GmbH · www.unicommunication.de

Printers VMK-Druckerei, Worms

Illustration credits Institute of Biology

Biotech


mailto:[email protected]

http://www.fu-berlin.de/presse

http://www.unicommunication.de

6 Freie Universität Berlin

Ω Depatment

A second core area in which the department is becomingincreasingly involved is bioinformatics. Here new bachelor andmaster’s degrees are planned, and the department will con-tribute to the teaching, but it will also participate in research inthis field. Handling large amounts of data is of major impor-tance in both genome research and in neurosciences, and com-bining biology with computer science represents a major chal-lenge that can only be met by interdisciplinary cooperation. Within the department itself there are plans to set up an inter-disciplinary "Bio-centre" that will bring together all the life sci-ences, including the research groups in human and veterinarymedicine. Biologists at the FU have long dreamt of a new build-ing to house such a centre, but it has never been possible. Nev-ertheless, it remains a goal for the future of the Institute of Biol-ogy.

www.chemie.fu-berlin.de/fbr.htmlE-Mail: [email protected]

Biology in Berlin

Die University biological research began in Berlin in 1810 withthe foundation of the Friedrich-Wilhelm University. The begin-ning was made with chairs with zoological and botanical orien-tations. A century later, parts of the university were relocated tothe Dahlem district - at that time still on the outskirts of the city.Various Kaiser Wilhelm Research Institutes and the state bio-logical agencies were also set up here, along with a new botan-ic garden. At the same time, the Botanical Museum was alsorehoused. A new building was erected specially for the Instituteof Plant Physiology, which was led from 1910 to 1923 by Got-tfried Haberlandt. Here he supervised the first cultivation tests

Department of Biology-Chemistry-Pharmacology

Most scientific progress nowadays is the result of interdiscipli-nary cooperation. In order to promote cooperation and innova-tion in scientific research and teaching, the former Departmentsof Biology, Chemistry and Pharmacology merged into a singledepartment in 1999. The leaner administrative structure in thenew large department makes it possible to operate faster andmore efficiently. In future, the department’s research activities will be devoted tolife sciences. Biology and biochemistry have already workedclosely together in the past on collaborative research projects.Contacts between crystallography and biochemistry will beintensified under the heading of structural biochemistry. Thereare also synergy effects to be achieved between organic chem-istry and microbiology which would provide new impulses, notonly for the work in this field, but also for pharmacology.

In the new combined department it will be possible to concen-trate on two core fields. One of these is research into transmit-ter substances and their receptor molecules. Transmitter sub-stances are agents of communication within and between cells,and they are of crucial importance, for example, for the opera-tion of the nervous system. In the new department, this field canbe investigated comprehensively at the levels of molecules, sys-tems, and the organism.

Ω Biology in Berlin

7Biologie-Chemie-Pharmazie



http://www.chemie.fu-berlin.de/fbr.html

9Biologie-Chemie-Pharmazie8 Freie Universität Berlin


neurological sciences. In addition, the institute is also closelylinked with the concept of evolution, and in this context withbiodiversity. The investigation of ecosystems and in particularthe effects of human activities on ecosystems are furtheraspects of the work.

In detail, the research concentrates on the following eight areas:

Ω Evolution, evolutionary biology, systematics in zoology; Ω Molecular developmental genetics of animals;Ω Molecular developmental biology/Developmental genetics

of plants;Ω Neurobiology and behavioural biologyΩ Ecology, ecophysiology, and ecotoxicology;Ω Systematic botany, geobotany and the Botanic Garden:Ω Molecular plant physiology;Ω Microbiology.

In recent years, neurobiology and molecu-lar plant physiology have gained increas-ingly in profile. This is reflected in the factthat the Collaborative Research Centre(Sfb 515) "Mechanisms of developmental-and experience-dependent plasticity inthe nervous system" and the postgradu-ate research group "Signal cascades in liv-ing organisms" are based at the Institute(neurobiology section). Research groupsconcentrating on molecular plant physiol-ogy are partof the DFG CollaborativeResearch Centre (Sfb 249) "Molecularphysiology, energetics and the regulationof metabolic processes in plants".

The Botanic Garden, the largest in Germany, and the BotanicalMuseum (together called BGBM) have been integrated in theFree University since 1995 as a central facility. This has openedup unique research opportunities in the fields of botany andplant ecology, particularly relating to the geographic distributionof species. The four separate libraries have been combined, andsince mid-2000 the central biological library is in the BotanicalMuseum.

There is intensive cooperation with the adjacent Max-PlanckInstitute for Molecular Genetics, and also with the Max-Del-brück Centre, with which there are associated professorships inthe fields of molecular developmental neurobiology andimmunology. In addition, the Institute of Biology participates inthe interdisciplinary research group on "Structural biology".

www.biologie.fu-berlin.de

on isolated plant cells and did work on phyto-hormones. WillyKükenthal was active at the Zoological Institute from 1918. Heis best known for his work on marine mammals, and also for astandard textbook on practical zoology - still in print in its 23rdedition. When the Freie Universität was founded in 1948, all the biolo-gists moved together into the former Institute of Plant Physiol-ogy. Today the building is occupied by research groups for api-dology, entomology, developmental biology, evolutionary biolo-gy, insect immunology and protozoology. The former residenceof the director (fig: in 1914) is now the location of the appliedzoology / animal ecology group. Many of the zoologists that came to the FU in its early yearswere representatives of systematic and phylogenetic evolution-ary research, generally in the tradition of Franz Eilhard Schulze,who had been in charge of the Zoological Institute of theFriedrich-Wilhelm University from 1884 - 1917. The Freie Univer-sität in West Berlin saw itself as a legitimate successor to the oldBerlin university, especially after the Zoological Institute of theHumboldt University in East Berlin formally ceased to exist in1969.

FU biologists were the first at a German uni-versity to establish a research group for ecolo-gy. Behavioural biology was also establishedas a sub-discipline at an early stage. Zoo-physiology was expanded considerably - con-centrating at first on metabolic physiology,and later also including neurobiology.

A new branch of research was developed in plant physiology.The technique of plant cell culture established by Jakob Reinertin the 1960s made it possible for the first time to regenerateentire plants from single cells, and on the basis of this, the insti-tute, which moved into a new building in 1971, established itsinternational reputation. Plant systematics - which had been theresponsibility of the Botanical Garden since 1959 - was alsogiven its own institute (Plant Geography and SystematicBotany). In the course of expansion, numerous areas ofresearch were added, including biochemistry, human biology,cell ultrastructure, developmental biology, then applied (plant)genetics in 1972, and microbiology in 1984.

The structure of the institute

Today, the Institute of Biology is divided into a total of 28 groupscarrying out research on the major biological topics of the 21stcentury. These include molecular biology and genetics with ref-erence to biotechnology and genetic engineering, and the newfield bringing together computer sciences and advances in the



http://www.biologie.fu-berlin.de


From our research

Neurobiology: Bees never forget either!

When animals learn, the connections between theneurones change and thus establish knowledge.This can then be used to improve the control ofbehaviour in the future. Among the thousands oftangled neurones, it is difficult to identify the spe-cific ones involved in the learning process, sincethey cannot be observed directly during the forma-tion of memory. It is therefore advisable to beginstudying a relatively simple nervous system, butone which is nevertheless in a position to learnquickly and to form a stable long-term memory. In the Neurobi-ology research group we are therefore investigating such prob-lems using the bee as our model. Bees can learn to recognise achemical signal even after they have been prepared for the opti-cal and electrical registration of their nerve functions. In this way,we can locate the site of memory formation and measurechanges in the switching of neurones. This makes it possible, forexample, to show that when a chemical signal has been learnt itleaves behind a precise neural representation in the brain. Thesetraces of memory can be followed back in the bee brain to singleidentifiable neurones, which opens up the opportunity to trackdown the switching elements which with their adaptable patternslay down the memory trace.

A special feature of the memory is the way itdevelops over time. After the initial learningprocess, an unstable short-term memory is firstformed, which is then transferred in stages over aperiod of hours and days into long-term memory.It has been found that these phases of memoriesare linked with the reactions of certain signallingmolecules in the neurones involved. A key role isplayed by the protein kinases. Their activationleads initially to the functional alteration of exist-ing molecules then later to the synthesis of newproteins - and finally to new structures. The memory content isnot stored by special molecules, but is manifested by the spatialpattern of synaptic efficacies caused at the cellular level by thesegeneral molecules, the switching of the neurones. This principleof memory storage also applies for humans, so that the beebrain provides a suitable model for studying general mecha-nisms of memory formation.

www.neurobiologie.fu-berlin.de/menzel.htmlE-Mail: [email protected]

Ω Research

Antennal

lobe of a

bee's brain

Crocus bee

Biotop


http://www.neurobiologie.fu-berlin.de/menzel.html



Ω Research

organs fulfil various functions in the courseof development of the larva. At first, all thecells of the gland (Fig. 3, green) produce adigestive secretion. In the middle of thefinal larval stage this function is restrictedto the anterior cells (Fig. 4, green) while theposterior section (Fig. 4, red) produceadhesive protein secretions. In the pre-pupal stage a third synthesis programme isinitiated in all cells (Fig. 5, blue). The genesinvolved in this are being analysed in orderto improve our understanding of the mole-cular processes behind the hormonallycontrolled reprogramming of differentiatedcells. E-Mail: [email protected]@zedat.fu-berlin.de

Protozoa: Small but essential

They might be very small indeed, butprotozoa play a vital role in the ecosys-tem of our planet. These single-cell ani-mals are found in the oceans, in fresh-water habitats, and in all soil forma-tions. Among other things, they regu-late bacterial numbers by feeding onthem. Another important role is that ofcommensalists in the stomachs of ruminants or in the gastro-intestinal tract of certain insects. Here they make an importantcontribution towards the degradation of the cellulose in thefood of their host. A more negative role is that of a highly dan-gerous pathogen, giving rise to illnesses such as sleeping sick-ness, malaria and coccidiosis. In humans suffering from AIDS,various opportunistic protozoa pose a considerable threat tothe weakened immune system, and are often fatal.

The research work of the protozoology group focuses on thenutrition of protozoa. How do these single-cell animals capturetheir food, and then ingestand digest it? An importantobjective is to identifyunderlying general princi-ples. Another topic of inter-est is the ecological signifi-cance of certain protozoa,the minute nanoflagellatesliving in the sediment ofaquatic habitats. In coopera-

Vampyrella

feeding on

algal fila-

ments

Amoebe

proteus

Fig. 4

Fig. 5

Fig. 3

Genetics: What the fruit fly has in common with you

Many of the important genes of the fruit fly Drosophilamelanogaster are surprisingly similar in structure and functionto human genes. In order to learn more about the way in whichgenes operate, it is possible to study Drosophila as a modelusing techniques from genetics and molecular biology, and thento draw conclusions about the importance of similar genes forhuman beings. In Developmental Genetics I a research group isstudying the genes involved in the formation of chromatin - thestructural material of chromosomes. A further project is work-ing on genes that are active in the brain nerve cells of Drosophi-la, regulating the hormone levels.

The DNA of eukaryotes is packed together withproteins in the chromatin of the chromosomes.Depending on the type and amount of the pro-teins, the chromatin influences the activity of thegenes. Proteins involved in the formation of thechromatin can have other additional functions. Weisolated a gene from the fruit fly, which we havenamed 'Domina', that also plays an important partin the development of the animal, in particular inthe formation of the nervous system, the eyes, andthe bristle structures. The 'Domina' gene codes for

a regulatory protein of the same name that is linked to specificsites on the chromosome. (Fig. 1). This gene corresponds to the 'winged-helix nude' gene (whn) inhumans, which plays a crucial role in the development of theimmune system. The molecular function of the 'Domina' / whnfactor is studied in transgenic Drosophilae.

As in humans, many of the fundamental process-es in the development and behaviour of insectsare controlled by hormones. Hormone produc-tion, in turn, is influenced by signals from thebrain - often in accordance with circadian rhythms.The molts of insect larvae and metamorphosis arethe most striking effects of the steroid hormoneecdysone and juvenile hormone. Both are pro-duced in the drosophila larva by the ring gland.Nerve cells have been identified in the brain of thelarva that have a direct link to the cells producing

the hormone (Fig. 2). Some of these cells have contacts to theinsect's 'biological clock'. Various genes are being investigatedthat are active in these nerve cells. The work of Developmental Genetics II involves the investiga-tion of genes in one of the target organs of the hormoneecdysone - the salivary glands of the Drosophila larva. These

Domina'

protein

(red and

yellow)

Nerve

cells

(fruit fly)

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mailto:kress:zedat.fu-berlin.de


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The following example of sophisticatedexchange of information between plants,feeding insects and their antagonistsgives an idea of just how complex thecommunication systems can be. It hasbeen known for some time that plants canrespond to insect attacks by giving offvolatile chemicals. These attract insectsthat prey on the pests or are their parasite.The change acts as an alarm signal. We were able to show thatpests do not even have to begin feeding on the plant - layingeggs on the leaves is sufficient to cause an alteration in the pat-terns of chemicals the plant releases, attracting specialised eggparasitoids. However, these will only be attracted if the plant iscarrying the "right" host eggs. Research is currently studyingnumerous aspects of the chemistry of the signals, the mecha-nism of signal induction, and the specificity of the system at thelevel of the plants, the herbivore insects, and the egg para-sitoids.

Chemical structures are analysed usinggas chromatography and mass spectros-copy. In order to detect the chemicals registered by the insectantenna, we combine gas chromatography with electro-an-tennography. In field studies and laboratory tests we study thebehavioural response of insects to chemical signals. We coope-rate with other laboratories to extend the scope of available che-mical, electrophysiological and molecular biological methods. E-Mail: [email protected]

Neuroanatomy: The locust and its synapses

A characteristic feature of animals is their mobility. But theywould not be able to move very well at all if they did not get awide range of feedback responses from their sensory organs.The Functional Neuroanatomy group studies such controlprocesses. Animals are still superior to robots when it comes tocrawling on branches or leaves, or climbing up rock faces. Forour studies, we have chosen the "simple" nervous system ofinsects, which have a widemotor repertoire: they walk,run, climb, swim and fly. Andfor the fine control of all thesemovements they have a wholearsenal of sensory cells andneuromodulatory neurones.The latter can alter the effi-ciency of neuromuscular syn-aptic transmission and the

African

locusts

tion with groups in Great Britain, Israel and theUSA we are also currently carrying out the first sys-tematic international survey of the drifting of pro-tozoa in ship's ballast water. Ocean-going shipstake on vast quantities of water as ballast, whichthey then discharge long distances away. Protozoa'kidnapped' in this way are often able to multiplyin an uncontrolled fashion in their new environ-ment.

The symbiosis between protozoa and insects isbeing studied with the example of termites and fla-gellates. These two groups of organisms aredirectly dependent on each other: the termitescannot decompose the cellulose they ingest with-out the flagellates, which in turn can no longer liveoutside the bodies of the termites.

In addition to research publications, the grouphas also produced standard text books on proto-zoology, as well as participating in numerous sci-entific film productions on topics relating to pro-tozoology and cell biology.

E-Mail: [email protected]

Exchanging information in nature: The chemistry of communication

Communication is not only important for exchanges betweenhumans in the information age, but is in fact vital to all organ-isms. Chemical signals offer a very sophisticated and wide-spread form of "silent" communication. The Applied Zoology/Animal ecology group is investigating communication systemsin which natural substances are used to carry information. Weconcentrate on insects that feed on plants, which account formore than a quarter of all living species. They are often found aspests in forests and on farm crops. Knowledge about the com-munication signals of insects can be used, for example, to con-

trol harmful pests by disturbing their transmis-sion. Comparative studies of the chemistry of sig-nals and their biogenesis also provide insightsinto the evolution of communicating species. Ifwe know the ecological and physiological condi-tions under which chemical signals are produced,perceived, and replied to, then we can draw con-clusions about the phenotypic plasticity of geneti-cally fixed communications strategies.

Amoebe proteus

Chilodonella with

ingested diatoms

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Behavioural biology: From duet to dialogue - rules and riddles of vocal communication

We are investigating how higher organisms suchas birds or mammals develop their signal systemsand how they use their rich repertoire of signalsduring social interactions. The organisation andaccomplishment of auditory-vocal memories isone priority topic. Many songbirds are experts in aform of learning that was long thought to be theprerogative of humans, so-called serial learning. Areal master singer is the nightingale (Lusciniamegarhynchos). Adult males have a repertoire ofabout a thousand different song elements, andthen use these to compose more than 200 differ-ent songs. We have started to elucidate the mech-anisms that enable the nightingale to memorisesuch immense amounts of information. We are also interestedin the rules underlying the ontogenetic development of theirsinging behaviour. Its developmental stages are studied bycomparing the tutored model song patterns and the final imita-tions produced at the end of the ontogenesis.

A second project is concerned with message and meaning inthe field of acoustic signals. Acoustic signals allow a rapidexchange of information, and are particularly useful when inter-acting individuals do not have visual contact. We are investigat-ing how birds and mammals use such benefits, and also whichrole they play during cases of laughter, crying, whispering orother nonverbal signals in human beings. Included in this pro-ject are issues like the influence of stress, anxiety, and otherstates in mammals such as non-human primates, dolphins orfarm animals. One aim of this research is to provide tools for anearly detection of stressful situations and thus eventuallyimprove the living conditions of farm animals.

Social intelligence and its biological foundations is the topic ofa further project. An intelligent organism is able to cope withnew problems individually,through cognitive mecha-nisms. The developmentof social competence insemi-wild Barbary mon-keys (Macaca sylvanus)and dolphins (Tursiopstruncatus) is of special in-terest. Part of the projectexamines the various fac-tors which influence the

Male

nightingale

approaching

its song

post

Semi-wild

Barbary

macaques

examining a

mirror

metabolism of the muscles.These mechanisms of plas-tic alteration of the nervoussystem are particularlyinteresting because theyalso play a crucial role inneural development. Inves-tigations have concentratedon the neurones thatrelease the so-called bio-

genic amines, which control a wide range of body functions. Wehave specialised on neurones that produce octopamine. Thissubstance is automatically released in every motoric processand apparently increases the efficiency of synapses and helpsthe muscles to conserve energy. Insects seem to have a particu-larly effective "energy conservation program", because the morefrequently and the longer a muscle is used the more economicalit is with energy.

When it comes to elucidating the mechanisms of development,insects are very good models. A pathway has been identifiedwhich the adult locust uses for flight control. The nymph of thelocust already has all the muscles and motor neurones of theadult insect, but does not yet have fully functional wings. Theseare only available after the final moult. We have found out that

during the development, activi-ty-dependent plasticity is veryimportant for the formation ofthe sensory system, whereasthe development of the motorsystem is more dependent onhormone control. In otherwords, developmental mecha-nisms are at work in the ner-vous system of insects thatwere previously assumed to berestricted solely to vertebrates.These processes must there-fore have been developed at avery early stage in the evolutionof the nervous system, andthey are perfect for adaptingthe neural circuits to the specif-ic demands of the organism inquestion.

www.neurobiologie.fu-berlin.de/Pflueger.htmlE-Mail: [email protected]

Ganglion with

neurones

Neurone in

culture

(3 days old)

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http://www.neurobiologie.fu-berlin.de/Pflueger.html


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under laboratory conditions, the alga has considerable potentialfor biotechnological applications. Currently, a pilot plant isbeing tested in cooperation with the Institute for Grain CropProcessing (Potsdam-Rehbrücke) in which polluted industrialwaste products (acidic gas scrubbing condensate and carbondioxide) are being used for biomass production of this red alga. E-Mail: [email protected]

Molecular adaptation: Bacteria under stress

The differing properties of thevarious types of cells are theresult of the activation of dif-ferent genes. But how aregenes activated or inactivat-ed? In order to study suchproblems, it is useful to havemodel systems that are easyto handle, for example bacte-ria. In bacteria, genes are typi-cally activated in response toenvironmental changes. Conditions are rarely ideal for bacterialgrowth, indeed, the environment usually imposes considerablestress. This is made worse by the fact that conditions alsochange rapidly. The Microbiology I research group is investigat-ing how bacteria adapt to such adverse conditions by changingthe activity pattern of their genes. Stress factors can be short-ages of nutrients, high or low temperatures, or increased osmo-larity. But which genes are activated under such conditions?How does a cell perceive stress? And finally, how does gene acti-vation take place at the molecularlevel?

In Escherichia coli, it has beenfound that a highly complicatedgenetic programme is activatedunder stress, centred on an essentialregulator protein known as Sigma S.Under a wide-range of stress condi-tions, the level of this protein risesdramatically, resulting in the activa-tion of 50-100 stress-protectivegenes. In addition to Sigma-S, awhole battery of other regulatory pro-teins are also involved in modulatingthis response. As a consequence, thecells become highly-resistant againstmany stress factors, and even changetheir morphology. Underlying this

Y. pseudotu-

berculosis

(fluores-

cence-

marked)

Regulation of degradation of

Sigma-S by stress signals

socialisation of young animals, and the experience that theygather in playful encounters. It seems certain that animals canderive socially important information from their observations.How they do so is being studied with the assistance of new testmethods.www.verhaltensbiologie.fu-berlin.deE-Mail: [email protected]

Extremophile red algae: Some like it hot

How does Galdieria sulphuraria survive inhot, acidic sulphur springs with pH valuesof 0.05 - 3, and temperatures of up to 60°C?The unremarkable unicellular red alga hasan exotic ecology and physiology. It is onlyfound in very limited habitats, and mainlygrows terrestrially, and in some cases evenendolithically, that is enclosed in rock. Inthe plant physiology research group we aretrying to unravel the mysteries of such"extremists".

In order to be able to survive in an extreme environment, it hasbeen necessary to develop a series of special adaptations. Forexample, in periods of very low light influx the alga uses metabo-lites such as sugar and amino acids from the dead cells of thepopulation for its own growth. The significance of heterotrophy(growth on a source of organic carbon in the absence of light) ishighlighted by the range of carbon sources that various strainsof Galdieria all over the world are able to use for their nutrition:some 50 different sugars, amino acids, sugar alcohols, andorganic acids. Nothing like it is known for any other organism.

How then does the alga perceive such a wide range of sub-strates and distinguish between them, and what uptake sys-tems, enzymes and regulation mechanisms have been devel-oped for this? It turns out that G. sulphuraria has sugar trans-porters and enzymes of previously unknown selectivity. Genesfor various key enzymes have already been isolated, and thelonger-term goal is to develop a detailed metabolic scheme forthis model organism. The strains from various geographical

locations are genetically very differentdespite considerable morphological andphysiological similarities. This suggeststhat the populations have been separatedfor a very long time, and also raises thequestion as to how G. sulphuraria managedto settle these biotopes. Because of itsextreme tolerance of acidity and heavy met-als, in combination with high productivity

G. sulphuraria

viewed

through the

microscope

Algal habitat

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http://www.verhaltensbiologie.fu-berlin.de



20 Freie Universität Berlin

Ω Research

response are mechanisms of signal transduction and regulationwhich are currently being studied at the molecular level.

This work is of more than purely theoretical interest. Many viru-lence genes in pathogenic bacteria are stress-regulated, and thecentral regulator Sigma-S plays a key role in the activation ofsome of these. Bacteria deprived of Sigma-S as a result of muta-tions are no longer pathogenic, and would in principle be suit-able as a living vaccine. Since inactivation of Sigma-S wouldleave the cells less virulent and highly susceptible to stress,Sigma-S may also be used as a target for novel antibiotics.

This prize-winning work has been carried on over the pasttwelve years, and has been located at the Freie Universität Berlinsince 1998. E-Mail: rhengga@ zedat.fu-berlin.de

Molecular photo-physiology: The inner life of mosses

As an important light receptor system, thephytochromes have a decisive influenceon the development of green plants. Theycontrol key aspects of development suchas germination, chlorophyll synthesis,growth and flowering. The nature of thisregulation is still not clear. Using modernmethods of molecular genetics, the Plant

Physiology research group is investigating these regulationmechanisms in primitive green organisms, mosses and cyano-bacteria.

Higher plants use the blue component of visible light to deter-mine the orientation for their growth - so-called phototropism.Paradoxically, moss filaments orient themselves on the basis ofred light photons. The aim of the group is to find out the role ofthe phytochrome in this process. Methods have been developedto transfer phytochrome genes into moss filaments and to bringthem to expression. In this way, the light detection in the cells atthe end of the filament can be manipulated. It is only in primi-tive plants that it is possible to modify the chromosomal genesthemselves. It was possible to identify the existence of a prokary-otic phytochrome - in the cyanobacteria Synechocystis. This phy-tochrome is very convenient for biophysical studies, since it canbe produced in large amounts. Various approaches are beingused to find out how the phytochrome works at the molecularlevel. The molecules are modified by means of molecular genet-ics in order to study the effects of changes on the structure andfunction. Crystallisation of the phytochrome molecules wouldalso make it possible to establish their three-dimensional struc-


A prokaryotic

phytochrome

ture using x-ray analysis. The phy-tochrome studies are supported by asub-projekt of the DFG CollaborativeResearch Centre 498 "Protein-Cofac-tor-Interactions in biological process-es” and a DFG-Project La 799/6-1"Isolation of genes for the Synthesisof the phytochrome chromophore”

A sub-project of the DFG Collaborative Research Centre 429"Molecular physiology, energetics, and regulation of primarymetabolism in plants" is working on the metabolism of lipids.Oil seed plants such as sunflowers are important sources ofunsaturated fatty acids for human nutrition. Knowledge of theregulation of the relevant metabolic pathways is therefore ofgreat importance. As a model organism, the researchers areusing the moss Physcomitrella patens. This is particularly well-suited for physiological studies because it can be easily cultivat-ed and genetically transformed. Furthermore, in contrast tohigher plants, it can be used to generate knock-out mutants byhomologous recombination. The goal of the work is to shedlight on the biosynthesis and function of phospholipids inplants. E-Mail: [email protected]

Cryoprotectin: Frost protection in winter hardy plants

Frost damage gives rise to considerableproblems for farmers in our climatezone. If we could improve the frost resis-tance of wheat by only 2°C, it would bepossible to increase the area on whichthe crop was grown by 25%. In order todevelop strategies for better frost protec-tion, it is first necessary to understand the mechanisms of frostdamage. The Developmental Biology research group is lookingat the molecular mechanisms of frost hardening and frost resis-tance of photosynthetic membranes (thylakoid membranes). Aparticularly interesting aspect is the protective role of the sur-rounding cytoplasm.

When outside temperatures fall below freezing point, tiny icecrystals form in the spaces between cells. The more the temper-ature falls, the more water is extracted from the cells andfreezes, further increasing the concentrations of solutes in thecells themselves. The water losses can be dramatic. At -20°C thelevel of liquid water in the cell can be reduced to 5%. Cryopro-tective proteins (cryoprotectins) from winter-hardy cabbage

Spinach

leaves

(r.: intact,

l.: frost

damaged)

Moss cells

filled with

oil drops

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regarded today as precursors of chloro-plasts and mitochondria (semi-autonomous intracellular organelles of theeukaryotes). That means that the enzymesof glycolysis / gluconeogenesis and theCalvin cycle have come together from twovery different bacterial groups in eukary-otes to form a new functional unit.Although these metabolic pathways in bac-teria and eukaryotes form a functional unit,it is not important in evolutionary termsthat the relevant genes in animals andplants have very different origins. A specialfeature of plants is that different enzymes(isoenzymes) are responsible for the gluconeogenesis in cytosoland in the chloroplasts. The occurrence of these isoenzymes isattributable to gene duplication in various phases of evolution,namely the bacterial, the early eukaryotic, or the early plantphase. This contradicts the hypothesis that isoenzymes all orig-inated at the same time and as a block. There are even examplesfor the independent evolution of such isoenzyme pairs manytimes over.

In other metabolic pathways, most of the genes of the mito-chondrial tricarboxylic acid cycle (an energy-generating meta-bolic pathway) came to the eukaryotic organisms with the evo-lution of mitochondria from alpha-proteobacteria. In contrast,the genes for the glyoxylate cycle, which is responsible for thetransition of acetate to glucose, were either formed in the micro-bodies from gamma-proteobacteria or by duplication of mito-chondrial genes of the tricarboxylic acid cycle. In the course ofevolution, the function of the metabolic pathways was thus pre-served. The individual eukaryotic genes were recruited, however,from very different organism groups. Such examples show thatthe evolution of genes is a much more complicated processthan has previously been assumed. E-Mail: [email protected]

Ecotoxicology: Biotests for a clean environment

A million years ago, our ancestors already began to adapt theirenvironment to their needs as they became human beings. Fora long time, low population densities meant that the environ-mental impact of human activities remained a local problem.However, with the growth of the world's population from 500million in 1650 to some 6 billion today, the problems havebecome global ones. Pollutants generated in the cities nowspread over the entire world and damage communities of livingorganisms (biocoenoses) even in the most distant regions ofthe world.

Gene trans-

fers in evolu-

tion (_) and

expression of

the gene

today (---)

leaves, which provide effective specific frost protec-tion for the membranes, have been identified andpurified. A new test system can now be used to testany substances for their cryoprotective properties.Thylakoid membranes are isolated from spinachleaves and frozen in a test tube under preciselydefined conditions. Before freezing, the "anti-freeze"

candidate is added to the membrane isolate. After thawingagain, the state of the membranes is determined, and the levelof protection provided by the substance can be assessed.

It could be shown that cryoprotectins are some 50 000 timesmore effective relative to their molecular weight than sucrose.Only a few millionths of a gram is enough to provide completein vitro protection of the thylakoid membrane. The cryoprotectinprevents the membrane from bursting. In this property it differsfrom all other proteins that have been considered as likely frostprotection candidates. The mechanism of these "anti-freeze"proteins is either unclear or they only have an indirect influenceon frost damage by reducing or promoting ice formation. Exam-ples of such proteins can be found in fish in the polar circles.Other proteins in insects influence compartment-specific nucle-ation. The aim of the work is to identify genes that code for thecryoprotectins, to transfer these to frost-sensitive crops, expressthem there and test their effects in the organism. http://userpage.fu-berlin.de/~schmittE-Mail: [email protected]

Metabolic pathways

Metabolic pathways are functional units whose enzymes catal-yse a certain sequence of reactions. In the past it was assumedthat such metabolic pathways arose in the course of bacterialevolution and were then passed on as a unit to the eukaryoticorganisms (animals, fungi, plants). Today many gene sequencesare known with which the origin of each gene and thus of theentire metabolic path can be determined.

The research group on the Metabolic Physiology of Plants isstudying the genetic expression of sugar phosphate metabolismas a sub-project of the DFG Collaborative Research Centre Sfb429 "Molecular physiology of plants." An important part ofsugar phosphate metabolism is the glycolysis/gluconeogenesis- a form of glucose degradation/formation, and the Calvin cycle,the key photosynthetic carbon reduction cycle in plants and bac-teria. We were able to clone and sequence many of the genes ofthe Calvin cycle of higher plants for the first time. Phylogeneticanalysis showed two eubacterial groups of organisms fromwhich the eukaryotic enzymes originate: cyanobacteria andalpha-proteobacteria. These two groups, respectively, are

Frozen

spinach cells

Ω Research


http://userpage.fu-berlin.de/~schmitt



Botanic Garden and Botanical MuseumBerlin-Dahlem

The Botanic Garden is special amongthe institutions of the Freie UniversitätBerlin, and indeed among the botanicalgardens of the world. With more than20 000 wild plant species on an area of43 hectares, it is one of the most richlystocked and largest gardens of its kind.On one third of the area, typical repre-sentatives of the flora of the temperatezones of the northern hemisphere arecultivated. Only a few steps will takevisitors from the European countryside past the steppe of Asiaand the Himalayas to the peaceful Japanese landscape and onto North America and its colourful Indian Summers.

Plants of the tropics and subtropicsgrow in the shelter of 15 publicglasshouses, including the TropicalHouse, the largest single-roofglasshouse in the world. Tropical cropsstrive side by side with orchids, cactiand – a major attraction – the giantwater lily. In Europe's only botanicalexhibition museum, models demonstrate some of the featuresnature usually conceals from view: microorganisms and sting-ing hairs, roots and the interior architecture of plants, as well asthe products of the world's most important crops. Evolutionaryand ecological processes are presented and explained in a waythat is easy to understand.

The library with some 400 000 booksand journals, and the herbarium with 3million specimens are also unique.Jointly they provide the basis for theresearch work at the Botanical Muse-um. Numerous students and post-graduates use the facilities for theirwork in systematic botany and plantgeography. Plant taxonomy is alsotaught.

www.bgbm.fu-berlin.de/bgbm/E-Mail: [email protected]


Ω Research

Some substances accumulat-ing in the soil have been intro-duced there intentionally, suchas insecticides, herbicides,fungicides, and also landfillwaste. Other substances alsoaccumulate, such as metals,explosives, salts, heating oiland fuel, carcinogenic organicchemicals, and pharmaceuti-cal products for humans andfor animals. The negative

effects of these substances are often only noticed when the sur-face vegetation shows signs of damage, or when humans andanimals fall ill. But by then it is already too late - the biocoeno-sis is irreversibly harmed. The Ecotoxicology and Biochemistryresearch group is investigating the influences of chemicals inthe environment on the behaviour and population developmentof soil invertebrates such as springtails, enchytraeid worms,threadworms, and single-cell organisms. Biotest systems aredeveloped using selected species which can indicate the habitatquality of soils by means of well-defined reactions. Togetherwith plant tests, microbiological and genotoxic investigations,these biotests form part of an internationally applied test batterywith which the damage to the soil and its retention function canbe determined. They can also be used to establish limit valuesand thresholds for planning authorities in contaminated areas,or to assess the need for decontamination measures.

Some substances are effective at the cel-lular level, and lead to profound develop-mental changes in animals. Chemicalsand pharmaceutical products resemblinghormones, for example, can lead to her-maphrodism or sex changes in animalseven though they are only present at envi-ronmental concentrations near or evenbelow current limits of detection. Abiotest is therefore being developed at themolecular level - the Ökotox-Genchip.This quick test system can show if a sub-

stance activates relevant genes of a test organism (thread-worm). Since humans possess comparable genes, this can pro-vide indirect evidence of the potential threat to people and theecosystem posed by the substance in question.

www.biologie.fu-berlin.de/agachazi/E-Mail: [email protected]

Enchytraeus

crypticus

(REM-image)

Folesomia

candida

Ω BGBM


http://www.biologie.fu-berlin.de/agachazi


http://www.bgbm.fu-berlin.de/bgbm/



Ω Studying

Biology in brief

Central address Freie Universität Berlin Institute of Biology Königin-Luise-Strasse 1-3 14195 Berlin Germany

Tel.: +49-30-838-54682Fax: +49-30-838-53925www.biologie.fu-berlin.deE-Mail: [email protected]

Research groups / Professors

Animal physiologyIrene Zerbst, [email protected] zoology / Ecology of animals Monika Hilker, [email protected] Bee researchBerkhard Schricker, [email protected] biology Dietmar Todt, [email protected] Didactics of biology N.N.Development biology Jürgen Schmitt, [email protected] genetics IGünter Korge, [email protected] genetics II Horst Kress, [email protected] physiology Hans-Dieter Pfannenstiel, [email protected] and biochemistry Rudolf Achazi, [email protected] EntomologyEkkehard Wachmann, [email protected] and morphology of tracheophytes Werner Greuter, [email protected] biologyWalter Sudhaus, [email protected] Functional neuroanatomy Hans-Joachim Pflüger, [email protected] biologyCarsten Niemitz, [email protected] Thomas Blankenstein, [email protected] physiology of plants Claus Schnarrenberger, [email protected] I Regine Henge-Aronis, [email protected]

Studying at the institute

The Institute offers two programmes for students working fortheir first biology qualification - a Diplom programme and aprogramme leading to a state certificate as a teacher. The diplo-ma programme can be completed in ten semesters, and thestate exam can take from six to ten semesters.

The beginning of each summersemester is marked by the GottliebHaberlandt lecture - in honour ofthe great botanist. The wintersemester is opened with theJohannes Müller lecture, preserv-ing the memory of this greatzoophysiologist. Both lectures areintroductions for new students andreunions for all members of the

institute. A modular course system offers advanced students awide choice. It is also possible to select a non-biological scienceas an additional option. Whether law, pharmacology, philosophyor computer science, anything is possible - provided of coursethat the lecture schedules can be coordinated.

Biology at the FU is characterised by the emphasis on research.Numerous excursions offer the opportunity to study in their nat-ural surroundings organisms that the students have alreadyencountered in their lectures and laboratory work, either on aday-trip to the countryside near the city, or for several weeks inthe South of France, the Canary Isles, Israel, or South America.The trips for one or two weeks to Sylt, Helgoland, the BalticCoast, Eschwege, or Carinthia in Austria are firm favourites andhave featured regularly in the programme for many years.

Students are encouraged tospend some time abroad, mak-ing use of the SOKRATES /ERASMUS programmes of theEuropean Union. Agreementshave been reached with partneruniversities in Ghent (Belgium),Valencia (Spain), Bordeaux, Lille(France), Crete (Greece), Birm-ingham, Cambridge, Swansea(Britain), Parma, Milan, Sienna(Italy) and Stockholm (Sweden).

Ω Biology in brief


http://www.biologie.fu-berlin.de




















Ω Biology in brief

Non-university institutions:Berlin: IInstitute for Water Ecology and Fishing; Max-DelbrückCentre; Max-Planck Institute (MPI) for Molecular Genetics;Robert-Koch Institute; Schering; Federal EnvironmentalAgency; Berlin Zoological Garden.Freiburg: MPI für Immunology. Gatersleben: Institute of Plant Genetics and Crop Research. Golm: MPI for Molecular Plant Physiology. Schmallenberg: Fraunhofer Institute of Environmental Chem-istry and Ecotoxicology. Tübingen: MPI für Developmental Biology.

International cooperation (selection) Argentina: Univesidad de Buenos Aires. Australia: University of Sydney. Cuba: Jardin Botanico National, Universidad La Habana. Czech Republic: Zoological Institute, University of Prague.Egypt: Ministry of Agriculture. France: Insitut Pasteur, Paris; Human Frontier Science Pro-gramme, Strasbourg. Great Britain: University of Leeds. Holland: Leiden University; Tropenbos. Israel: National Institute of Oceanography, Haifa; University of Tel Aviv. Italy: Instituto Ortobotanico, Palermo University. Japan: Metropolitan University of Tokyo. New Zealand: Department of Conservation, Tongariro. Russia: State University of Irkutsk; Lossomov State University,Moscow; Voronezh State University. Sweden: Lund University. USA: United States Department of Agriculture; NIH Bethesda,Maryland; Biocommunication Lab, UC/Davis; North DakotaState University, Fargo; University of Hawaii; University ofTexas/Houston; New York University; University of Arizona,Tucson; Sonoma University, California; University of Utah, SaltLake City; College of Environmental Science, State UniversitySyracuse, N.Y.

Academic qualifications awarded: Diploma in Biology State teaching qualification for biology

ServicesStudent counselling: Tel: 838-53840Student office: Tel: 838-55550;

e-mail: [email protected] Central biology library in

Botanical Museum, Tel: 83006-191

Microbiology IIRobert Mutzel, [email protected]. developmental biology of plants N.N.Mol. developmental neurobiologyFritz Rathjen, [email protected] genetics and cytogeneticsN.N. Morphology of phanerogamsHartmut Hilger, [email protected] Menzel, [email protected] physiologyElmar Hartmann, [email protected] Hausmann, [email protected] geneticsHorst Nöthel Soil zoology and ecologyGerd Weigmann, [email protected] botany and plant geographyWolfgang Frey, [email protected] and evolutionary biologyN.N.

Collaborative research centre:Sfb 515: "Mechanisms of developmental- and experience-dependent plasticity in the nervous system" Postgraduate research group "Signal cascades in living organ-isms"

Central facility Botanic Garden and Botanical Museum (BGBM)(www.bgbm.fu-berlin.de/bgbm)

Students and personnel (March 2000)

1335 students 29 professors 65 scientific personnel80 other personnel86 student tutors

Research and academic achievements (1999)

Funding / third-party funding: DM 1.3m /DM 5.7mDegrees awarded 80Ph.D.s 42Habilitations 6

Scientific cooperation in Germany (examples)Universities: Aachen; HU Berlin; Bonn; Braunschweig; Frank-furt; Göttingen; Cologne; Mainz; Munich; Ulm;Witten/Herdecke; Würzburg

Ω Biology in brief










http://www.bgbm.fu-berlin.de


Ω Dies ist ein Thema

Ulf

Kai

ser


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Biology-Chemistry-Pharmacology Institute of Biology Freie ...userpage.fu-berlin.de/~biolehre/docs/bioen.pdf · Biology-Chemistry-Pharmacology Most scientific progress nowadays is