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Into the Natural Microbial World
Norman PaceMCD Biology
University of Colorado, [email protected]
Dedicated to Carl Woese
• The molecular Tree of Life - new perspective on microbial diversity.
• From phylotype to phenotype: A Yellowstone example.
• Expansion of the Big Tree: A mapping project.
• We need to heed what the Tree says about biological organization -- our textbooks (mostly) get it wrong!
Outline
Haeckel, 1866
Making Sense of Sequences: Molecular Phylogeny
1. Align sequences so that “homologous” residuesare juxtaposed.
2. Count the number of differences between pairs of sequences; this is some measure of “evolutionary distance” that separates the organisms.
3. Calculate the “tree”, the relatedness map, that most accurately represents all the pairwise differences.
Carl WoesePhoto by Jason Lindsey,U. Ill. Alumni Magazine
You are here -->
Some Lessons from the Big Tree:
- Three main relatedness groups, Eucarya, Bacteria, Archaea.
- Origin is on the bacterial line of descent: Eucarya and Archaea are related to the exclusion of Bacteria.
- Chloroplasts and mitochondria are of bacterial origin.
- The eucaryal nuclear line is as old as the archaeal line; the procaryote-eucaryote model for biological organization was wrong!
- Sequences are identifiers of organisms - you don’t need to cultureto identify!!
Who’s in here?What are they doing for a living?
From phylotype to phenotype - A Yellowstone story
Carrine Blank
Phil Hugenholtz
Sample --> DNA --> PCR --> RFLP --> Sequence
Sample Analysis:
Anna-LouiseReysenbach
Universal Libraries Composite
Thermus / Deinococcus
5%
Thermodesulfobacteria
2%
Thermotogales; EM32%
Bacteria; Novel Group
5%
Delta-Proteobacteria2%
Alpha-Proteobacteria2%
Archaea2%
Aquificales: Hydrogenothermus
2%
Aquificales: Hydrogenobaculum
1%
Aquificales; Hydrogenobacter
77%
John Spear
We do need cultures --But not mindless cultivation:
If you want to do microbial ecology by culture,you have to do what microbiologists have always
avoided------
• Before you start, determine what you are trying to culture.
• Note that most biomass out there is autotrophic.
• Study mixed cultures - much microbial life is syntrophic.
• Minimize O2 - Most microbial diversity (probably) is suboxic.
Guerrero Negro halite-gypsum-lifePhoto by John Spear John Spear
Jeff Walker
We are embedded in a microbial world !
Dan Frank
Kirk Harris
Time for Change: a public service message
Time for Change: a public service message
The fundamental issues in any scientific discipline:
ORDER - Organization and relationshipse.g. the periodic table for chemistse.g. phylogenetic relationships for biologists
CHANGE - How things evolvee.g. the Hertsprung-Russell star seriese.g. biochemical mechanismse.g. the Tree of Life
A Big Lesson from the Big Tree -
The “Procaryote/Eucaryote” Concept:
Procaryote --> Eucaryote
is an incorrect model for large-scale
biological organization and evolution.
The public service message:
Haeckel, 1866
“Procaryote” means“non-eucaryote,” nothing more.
Not being something is
not a scientificallyvalid concept or name.
Procaryote/Eucaryote: The Model (Chatton, 1937)
1. All eucaryotes are “of a kind,” specifically related to one another.
2. All procaryotes are “of a kind,” related to one another to the exclusion of eucaryotes.
3. There are two forms of cellular organizationand function.
4. Procaryotes (Haeckel’s “monera”) are simpler than eucaryotes.
5. Procaryotes gave rise to (more advanced) eucaryotes.
Procaryote/Eucaryote: The Test
1. All eucaryotes are “of a kind,” specifically
related to one another. True
Procaryote/Eucaryote: The Test
1. All eucaryotes are “of a kind,” specifically
related to one another. True
2. All procaryotes are “of a kind,” related to
the exclusion of eucaryotes. False
Procaryote/Eucaryote: The Test
1. All eucaryotes are “of a kind,” specifically
related to one another. True
2. All procaryotes are “of a kind,” related to
the exclusion of eucaryotes. False
3. There are two forms of cellular organization.and function. ?
Procaryote/Eucaryote: The Test
1. All eucaryotes are “of a kind,” specifically
related to one another. True
2. All procaryotes are “of a kind,” related to
the exclusion of eucaryotes. False
3. There are two forms of cellular organization.and function. ?
4. Procaryotes (Haeckel’s “monera”) are simpler than
eucaryotes. NA
Procaryote/Eucaryote: The Test
1. All eucaryotes are “of a kind,” specifically
related to one another. True
2. All procaryotes are “of a kind,” related to
the exclusion of eucaryotes. False
3. There are two forms of cellular organization.and function. ?
4. Procaryotes (Haeckel’s “monera”) are simpler than
eucaryotes. NA
5. Procaryotes gave rise to (more advanced) eucaryotes.
False
What does it matter if we call them “procaryotes?”
“Procaryote” is scientifically unjustified, invented and accepted to fill a gap in knowledge.
The name has false implication in deep evolutionary
matters.
The false understanding of “procaryote” quenches legitimate inquiry.
It teaches our students false concepts at the most
fundamental level: Order in Biology.
What else to call them??
If you mean “the little stuff out there,”try “microbes/microbial” There’s a bunch of
little/weird (to us) eucaryotes out there, too!
If you are talking functional or evolutionaryissues, you need to be more precise than
“procaryote.”
To students the concept is in the language;
thus, in the language is the understanding.
Carl WoeseDavid StahlDavid LaneGary Olsen
Bernadette PaceMitchell Sogin
Steve GiovannoniKate Field
Tom SchmidtElizabeth Raff
Rudy RaffMichael Ghiselin
Sean TurnerEd DeLongDan Distel
Tineke Burger-Wiersma
Gene WickhamPeter EdenJim Brown
Annick Wilmotte
Art HarrisonAnna-Louise Reysenbach
Lori GiverEsther Angert
Sue BarnsMatt Jeffries
Phil HugenholtzBrett Goebel
Austin BrooksMarissa Ehringer
Karen HershbergerScott DawsonDiana NorthupChris PitulleMike Tanner
Jose de la TorreMike DojkaEric Lyons
George SpiegelmanKirk HarrisDan Frank
John SpearHazel BartonScott KelleyAlicia Berger
Jeffrey WalkerCarrine Blank
Ruth LeyLars AngenentUlrike TheisenAlli St. Amand
Mary Ann DeGroote
Tina SalmassiJosh Wilcox
Dominic PapineauAndrew Dalby
Chuck RobertsonLaura Baumgartner
Leah FeazelKimberly Ross
Piret KollMari Rodriguez
(Micrograph: a hypersaline microbial mat Thanks to NIH, NSF, DOE, ONR, NASA Photo by Ruth Ley) for $upport over the years
Thanks! to :