12.158 Lecture 5 - MIT OpenCourseWare · Methylococcus capsulatus , Bird et al., (1971) •ββ-hopane and ββ-homohopane in . Bacillus acidocaldarius, de Rosa 1973 • Fossil hopanoids

12.158 Lecture 5

• Hopanoids and other cyclic terpenoids

– Structures, biosynthesis, diagenesis – Hopanoid hydrocarbons;

stereochemistry vs maturity

– Hopanoids as process and

environment indicators

1

Hopanoids

• First recognised as a class of

C30 pentacyclic triterpenes

found in ferns, mosses and

dammar resins

• �Hopane� named after the

Dipterocarp plant genus Hopea,

itself after botanist John Hope

• Biosynthetic kinship to sterols,

tetrahymanol & oleanoids, via

squalene recognised in 60�s

© Gaines, Eglinton & Rullkötter

These images have been removed due to copyright restrictions.

2

Evolution of Hopane & Sterol Bioynthesis

BHP

Squalene Diploptene

Squalene epoxide

o2

O

BACTERIA

HO HO C24 substitution by algaeLanosterol Cholesterol

some bacteria - Methylococcus Mycobacteria, Myxobacteria

EUCARYA o2

3

Structure and Function of a Squalene Cyclase K. Ulrich Wendt, Karl Poralla, Georg E. Schulz *

The crystal structure of squalene-hopene cyclase from Alicyclobacillus acidocaldarius was determined at 2.9 angstrom resolution. The mechanism and sequence of this cyclase are closely related to those of 2,3-oxidosqualene cyclases that catalyze the cyclization step in cholesterol biosynthesis. The structure reveals a membrane protein with membrane-binding characteristics similar to those of prostaglandin-H2 synthase, the only other reported protein of this type. The active site of the enzyme is located in a large central cavity that is of suitable size to bind squalene in its required conformation and that is lined by aromatic residues. The structure supports a mechanism in which the acid starting the reaction by protonating a carbon-carbon double bond is an aspartate that is coupled to a histidine. Numerous surface helices are connected by characteristic QW-motifs (Q is glutamine and W is tryptophan) that tighten the protein structure, possibly for absorbing the reaction energy without structural damage.

4

SQUALENE

3

HOPENE

B1:H B2

22

29

1

The proposed reaction steps in squalene-hopene cyclases involving carbocationic intermediates. The general acid B1:H protonates (H) squalene at C3, whereas the general base B2 deprotonates at C29 of the hopenyl cation. In a side reaction, the cation is hydroxylated forming hopan-22-ol (i.e. diplopterol)

Image by MIT OpenCourseWare.

5

This image has been removed due to copyright restrictions.

Figure 5. The color-coded surface representations (30) with nonpolar (yellow), positive (blue), and negative (red) areas. (A) View similar to Fig. 2 but rotated around a vertical axis and sliced. The cutting plane (checked) opens the large internal cavity with the bound inhibitor LDAO. The nonpolar channel runs to the left, opening into a nonpolar plateau. The channel constriction (C) appears closed, but it is mobile enough to be readily opened. At the upper left, hopane (two views) is shown at scale. (B) View similar to Fig. 2 directly onto the 1600 Å2 nonpolar plateau with the channel entrance (E) at its center and two nonpolar side chains pointing to the outside. This is the only large nonpolar region on the surface

6

Discovery of Geohopanoids

• Hopane identified in Green River Shale by Burlingame, Haug, Belksky &

Calvin, PNAS, 1965.

• C27-C31 Triterpanes in optically active petroleum distillates, Hills &

Whitehead, Nature 1966

• Homohopane in Green River, Ensminger Maxwell (Bristol & Strasbourg,

�72)

• Extended hopane series to C35 ubiquitous in the geosphere incl. petroleum,

soils and diverse sediments

Ensminger, van Dorsselaer, Spyckerelle, Albrecht, Ourisson (Strasbourg) and

Eglinton, Maxwell, Kimble, Philp & Brooks (Bristol) 1973-4

Hills & Whitehead (BP) speculated there was a C35 precursor 7

Hopanoids in Bacteria & Rocks?

• Diploptene (C30) identified in bacteria & cyanonbacteria, de Rosa (1971)

incl. Methylococcus capsulatus , Bird et al., (1971)

•ββ-hopane and ββ-homohopane in Bacillus acidocaldarius, de Rosa 1973

• Fossil hopanoids exhibit αβ, βα and ββ stereochemistry with 22S+R; ββ

and βα recognized as less stable than αβ

• C30 C-3 oxygenated triterpane alcohols and ketones in Messel, but not

equivalent C30 hydrocarbons suggest many hopane hydrocarbons entered

as 3-desoxy components

• Mystery ‘almost’ solved when Forster, Biemann et al characterized a C35 tetrahydroxy triterpenoid in Acetobacter xylinum (1973)

8

Hopanoids

Biochem. J. (1973) 135, 133-143

Printed in Great Britain 133

The Structure of Novel C35 Pentacyclic Terpenes from Acetobacter xylinum

By HANS J FRRSTER * and KLAUS BEIMANN Department of Chemistry, Massachusetts Institute of Technology,

Cambridge, Mass. 02139, U.S.A.

And W.GEOFFREY HAIGH Biomedical Research Laboratory, Dow Corning Corporation, Midland,

Mich, 48640, U.S.A.

And NEIL. H.TATTRIE and J.ROSS COLVIN, Division of Biological Sciences, National Research Council of Canada,

Ottawa K1A OR6, Canada

(Received 14 February 1973)

9

Patterns of Geohopanoids in GC-MS

Geochemists figured that the absence of C28 homologue and pairs of peaks from

C31-C35 are informative about side-chain structure

10

Hopanoids

Courtesy Elsevier, Inc., http://www.sciencedirect.com. Used with permission.

11

http://www.sciencedirect.com

Hopanoids


12


Hopanoids

Biochem J. (1973) 135, 133–143 133 Printed in Great Britain

The Structure of novel C35 pentacyclic terpenes from Acetobacter xylinum

By HANS J. FÖRSTER* and KLAUS BIEMANN Department of Chemistry, Massachusetts Institute of Technology,

Cambridge, Mass. 02139, U.S.A.

and W. GEOFFREY HAIGH

Biomedical Research Laboratory, Dow Corning Corporation, Midland,

Mich. 48640, U.S.A.

and NEIL H. TATTRIE and J. ROSS COLVIN

Division of Biological Sciences, National Research Council of Canada,

Ottawa K1A OR6, Canada

(Received 14 February 1973)

A novel C35 terpene and its monounsaturated analogue were isolated from cultures of Acetobacter xylinum, together with traces of their C36 homologues. These substances were found to be hopane derivatives substituted by a five-carbon chain bearing four vicinal hydroxyl groups. For the parent hydrocarbon the term bacteriohopane is proposed. The elucidation of the structures utilized high-resolution mass spectrometry of the terpenes, degradation to C32 hydrocarbons and detailed mass-spectrometric comparison of these with C32 hydrocarbons synthesized from known pentacyclic triterpenes. High-resolution mass-spectral data of the terpenes are presented. N.m.r. data are in agreement with the proposed structures, which are further supported by the isolation from the same organism of 22-hydroxyhopane and derivative hopene(s).

13

Hopanoid quotes

• The formation of the more stable αβ hopane

epimers could constitute , in a given environment, a geochemical clock unless they happen to be still unrecognized constituents of living organisms

�.......... Ensminger et al., Advances in OG..1973

• The total amount of geohopanoids is estimated to be ~1012 tons and same order as total mass of organic carbon in all living organisms

�.......... Ourisson and Albrecht, Geohopanoids, the most abundant natural products on Earth, Acc Chem Res 1992

14

11 known ring systems

Ring Variations

2

3 Δ6

Δ11 C-2 Me CYANOBACTERIA

Summons et al., 2000 22R

C-3 Me METHANOTROPHS (Acetic Acid bacteria)

Δ6 and/or Δ11 ACETIC ACID BACTERIA (Methanotroph)

15

Side Chain Variations

OH OH

OH XY

Z

TETRA: X=OH, NH2, composite; Y = Z = H

Composite

HEXA: X = NH2; Y = Z = OH

30 31

PENTA: X = OH, NH2, composite; Y = OH, Z = H X = OH, Y = H, Z = OH

O NH2

OH

OHOHOH

NH

O

NH2 NH2

O

O

COOH

OH OH

OH

16

Analysis Of Bbiohopanoids

• Highly functionalised, amphiphillic • Not amenable to conventional GC-MS • Side chain cleavage (Rohmer et al., 1984)

– Periodic acid/sodium borohydride – Product structure directly related to number

and position of functional groups in side chain

• Specific nature of functional groups lost

17

Periodic Acid Oxidation

OH

TETRA O OH

OH OH

32 OO OOH H5IO6/NaBH4 32-hopanol OH H

OH

OH OH

OHOH 31

PENTA 31-hopanol H5IO6/NaBH4 OH

HEXA OH

OH OH OH H5IO6/NaBH4 30-hopanol30

OH OH NH2

18

Hopanoids

The effect of thermal stress on source-rock quality as measured by hopane stereochemistry

WOLFGANG K. SEIFERT, J. MICHAEL MOLDOWAN

Chevron Oil Field Research Company, P.O. Box 1627, Richmond, California 94802, U.S.A.


In: A.G. Douglas and J.R. Maxwell, Editors, Advances in Organic Geochemistry, Pergamon Press, Oxford (1980), pp. 229–237

19

Hopanoids & Thermal Maturity

20

Structural Diversity of Hopanoids


21


Hopanoids and Physiology

Distribution of hopanoid triterpenes in prokaryotes

Rohmer, M. , Bouvier-Nave, P. , Ourisson, G. Ecole Nationale Superieure de Chimie de Mulhouse, Universite de Haute Alsace, 68093 Mulhouse Cedex, France

Present in 50% of some 100 strains across diverse taxa

In almost all cyanobacteria, obligate methylotrophs , purple non-sulfur bacteria and diverse chemoheterotrophs

Absent from purple sulfur bacteria, archaebacteria

Not detected in any anaerobe

Bacteriohopane tetrol most common

Journal of General Microbiology Volume 130, Issue 5, 1984 1137-1150 22

Functional Role of Hopanoids?

Proc. Natl. Acad. Sci. USA Vol. 76, No. 2, pp. 847-851, February 1979

Molecular evolution of biomembranes: Structural equivalents and phylogenetic precursors of sterols

(triterpenes/tetraterpenes/prokaryotes/pre-aerobic evolution)

MICHEL ROHMER, PIERRETTE BOUVIER, AND GUY OURISSON

Rohmer & Ourisson, 1976

Rohmer et al., 1979

Kannenberg & Poralla, 1980

Many lines of evidence show an association of

BHP with cellular membranes

Image courtesy of Michel Rohmer. Used with permission.

Evolution

23

First Report of 3-Methyl Hopanoids


24


Discovery of Methylated Hopanoids

Acetobacter BHP hypothesized to be 3

methylhopanoids on biosynthetic grounds

25


Discovery of

Methylated Hopanoids

Proof of structure of 3-methyl BHT by

correlation with synthetic 3-methyl

bishomohopane

Stereochemistry at C3 not assigned

until 1985

3β by nmr &

comparison with 3β-methyldiplopterol

& 3β-methylhopan-29-01 synthesized

from 22-hydroxyhopan-3-one.

3β-methylhopanoid content of A.

pasteurianus ssp. pasteurianus could

be increased up to 60% of

the total hopanoid content by addition

of L-methionine, the actual methyl

donor, to the culture medium.

26

Discovery of 2β-Me Hopanoids

Prokaryotic triterpenoids 2.2ß-Methylhopanoidsfrom Methyfobacterium organophilum and Nostoc muscorum, a new series of prokaryotic triterpenoids

Philippe BISSERET, Magali ZUNDEL and Michel ROHMER

Ecole Nationale Suptrieure de Chimie de Mulhouse

Eur. J. Biochem. 150, 29-34 (1985)

©FEBS 1985

27

2β-Me Hopanoids

2β by nmr & direct comparison with 2β-methyldiplopterol

synthesized from 22

hydroxyhopan-3-one.


28

2α-Me Hopanoids Tetrahedron Vol 47, No. 34, pp 7081-7090, 1991 ©1991 Pergamon Press pic Printed in Great Britain

2 Į -Methylhopanoids: First Recognition in the Bacterium Methylobacterium organophilum and Obtention via Sulfur Induced Isomerization of

2ß-Methylhopanoids. An account for their presence in sediments.

P Stampf. D Herrmann. P Bisseret. M Rohmer

c. 5% methyldiplopterols 2α by 13 C nmr & direct comparison with 2α-methyldiplopterol

synthesized from 22-hydroxyhopan-3-one.

Sloppy methylase? Any 2α-methyl in Nostoc or

Rhodopseudomonas?

29

Geological Occurrence of Methyl Hopanoids

• Fossil methyl hopanes reported in sedimentary

rocks and oils eg SEIFERT and MOLDOWAN, 1978;

ALEXANDER et al., 1984; MCEVOY and GIGER,

1986; SUMMONS and POWELL, 1987

• Tentatively but erroneously thought to be 3-methyl hopanes based on the reports of 3-methylhopanoids in methylotrophs

• Complex mixtures precluded any spectroscopic

analysis other than GC-MS

• Synthetic approaches already developed by

Rohmer but not applied to geo hopanoids

30


31

1 0 0

%

00 0 3 0 7 2 4 0 1 1 0 0

%

00 0 3 0 7 2 4 0 1 1 0 0

%

6 5 .1 9 00

0 3 0 7 2 4 0 1 1 0 0

%

6 3 .9 8 6 4 .8 3 6 3 9 8 6 4 .8 3 0

0 3 0 7 2 4 0 1 1 0 0

6 4 .0 9

%

6 3 .9 8 6 4 .2 5 6 0 .0 0 6 2 .8 1

0

0 3 0 7 2 4 0 1

6 3 .9 8 1 0 0

% 6 1 .7 6 6 2 .6 3

6 3 .7 4 6 4 .1 3

0

6 8 .4 6

7 1 .2 8 7 1 .7 7

6 6 .1 4 6 7 .0 2 6 9 .0 4 7 1 .0 9

7 2 .4 3 7 3 .2 9 7 4 .2 2454.452 > 205.194

6 7 .9 7 6 8 .3 8

6 6 .8 8 6 8 .9 6 7 0 .3 9

6 6 .2 2

6 6 .4 7

6 9 .1 6 6 9 .4 5 6 6 .9 6 6 8 .0 3

6 6 .1 2 6 6 .3 7

6 6 .8 8 6 7 .1 1 6 7 9 7 6 7 .9 7

6 6 .1 4 6 6 .3 9

6 6 .7 2

6 7 .9 9 6 8 .4 06 8 .4 0

6 6 1 26 6 .1 2 6 6 .3 9

7 0 .3 9

440.437 > 191.179

440.437 > 205.194

426.421 > 191.179

426.421 > 205.194

6 0 .0 0 6 2 .0 0 6 4 .0 0 6 6 .0 0 6 8 .0 0 7 0 .0 0

412.406 > 191.179

7 4 .0 0 7 6 .0 0 7 8 .0 07 2 .0 0

GC with MS-MS -> isomers of each individual homologue to be seen in

separate chromatograms

32


Compparison of 2α

methyl hopane and 3β

methyl hopane with

This image has been removedThis image has been removed fossil hydrocarbonsfossil hydrocarbons due to copyright restrictions.

Sample was an iimmatture OO drdoviiciian

sediment with two series of methyyl

hopanes

33


Relative retention timesRelative retention times used to assign identity

to C27-C35 series’

Sample s an immature

Ordovician kukersite

S di t th l h d i d f th l l f BHPSedimentary methyl hopanes derived from methyl analogues of BHP

34

O2-Diagnostic Bacteriohopanes ??O2 Diagnostic Bacteriohopanes ??

R

OH OH 21

32

19

35 22 diagenesis

1

R3 OH

32 17

R2 2

43

10

1125

29 14 16

35

R1

cyanobacteria

diagenesis maturation

cyanobacteria cyanobacteria δ13C -20 to -35 ‰

1

R3

OH

OH

OH 21

32 1711

19

25

29 14 16

35

OH

22

NH2

diagenesis maturation

12

43

10 29

methanotrophic bacteria methanotrophs δ13C -45 to -80 ‰

Jahnke et al., 1992, 1993; 1999; Summons & Jahnke, 1988, 1990; Summons et al., 1994, 1999

35

Isotopic Signature of 3-Methyl Hopanoids

pMMO sMMO

C-isotopic fractionation in biomass of M. capsulatus:

varies as a function of substrate, growth stage, MMO type

Summons et al., GCA, 1994 Courtesy Elsevier, Inc., http://www.sciencedirect.com. Used with permission. 36


Isotopic Signature of 3-Methylhopanoids

Biomass-triterpenoids ε ~ 36‰Biomass triterpenoids ε 36‰

Distribution and C-isotopic fractionation in hopanoids of M.

capsulatus as function of growth stage

Summons et al., GCA, 1994 Courtesy Elsevier, Inc., http://www.sciencedirect.com. Used with permission. 37


Geological Occurrence of 3-Methylhopanoids

Advances in Organic Geochemistry 1991 Org. Geochem. Vol. 19, Nos 1-3, pp. 265-276, 1992 Printed in Great Britain

An isotopic biogeochemical study of the Green River Oil shale

JAMES W. COLLISTER, ROGER E. SUMMONS, ERIC LICHTFOUSE, and J. M. HAYES Biogeochemical Laboratories, Department of Geological Sciences and Chemistry Geology Building, Indiana University, Bloomington, IN 47405, U.S.A. and Bureau of Mineral Resources, G.P.O Box 378,

Canberra, A.C.T 2601, Australia

This image has been removed due to copyright restrictions. Please see Figure 7 in the above article.

38

Hamersley Basin biomarker & isotopic records

Courtesy of National Academy of Sciences, U. S. A. Used with permission. Source: Eigenbrode et al (2008) National Academy of Sciences, USA. Eigenbrode et al, PNA S Copyright (c) 2008, National Academy of Sciences, U.S.A. 2008 39

Cyyanobacterial Lippids 9

COOH OH phytol11

C 16-18 fattyy acid and PUFA16 18

n-heptadecane

7

7- & 8

methylheptadecane

88 OHOH

7 11

COOH

β tβ-carotene

R

7 11 dimeth lh tadecane7,11-di thylhept d hopanoids & 2-methylhopanols

40

Are 2-methylhopanes biomarkers for

cyanobacteria and O photosynthesis?cyanobacteria and O2-photosynthesis?

• Sppecificityy of 2-MeBHP for Cb? ~30% of Cb surveyyed ((Talbot et al, OG 2008))

– Methylobacterium, N-fixing soil bacteria (Rhizobiales) – Rhodopseudomonas palustris (Rashby et al., 2007) – Commonly present in heterocystous cyanobacteria – Relatively abundant in a Baltic Sea strain ofRelatively abundant in a Baltic Sea strain of NodulariaNodularia

• What are the environmental occurrences? – Very abundant in hot spring mats; low levels in marine hypersaline Cb mats

• What are the biological functions of BHP & methylated BHP? – Membrane-associated in P luridum and Mc Bath; pCO2 control in Phormidium?

• Geological occurrences? Secular in shales; Always at OAEsGeological occurrences? Secular in shales; Always at OAEs

• What is the biosynthetic pathway? – No unsaturated precursors; Radical SAM? See Paula’s talk

• Are biosynthetic pathways conserved over geological time? Does a

biomarker found today mean the same thing as one 500Myr old?

41

2-MeHopanes vs Lithology & Paleogeography

0 25

0.30

Carbonate

Marl

Distal Shale

0.20

0.25

x

Distal Shale

0.15

ylho

pane

Inde

x

0.10

2-M

ethy

0.05

0.00 -90 -70 -50 -30 -10 10 30 50 70 90

Paleolatitude 42

2-Me BHP - Biomarkers for Cyanobacterial Photosynthesis ?

0 30

2-M

ethy

lhop

aane

Inde

xx

0.30

0.20

0.10

Carbonate

Marl

Distal Shale

200 400 600 800 1000 1200 1400 1600 1800 Sediment Age MYA

43

2-Me BHP - Biomarkers for Cyanobacterial Photosynthesis ? Frasnian-Famennian

Toarcian OAEOAE

Permian-Triassic Cretaceous OAEs

0.30

x

Carbonate

Marl

Distal Shale

0.20 ane

Inde

xet

hylh

opa

0.10

2-M

e

0 100 200 300 400 500

Sediment Age MYA

600

44

2-Methylhopane Index for Sediments/Oils

Barney Creek Fm #1698Barney Creek Fm #1698

αβ-hopane

412 ->191

2α(Me)-αβ-hopane2α(Me) αβ hopane

426 >205

2α-MeH Index

2 (M )/2 (M ) β 426 ->205= 2α(Me)/2α(Me)+αβ

1:00:00 1:04:00 Time

45

2α-Methylhopane index 2.72-2.56 Ga samples from

the Hamersleyy Province

Courtesy of National Academy of Sciences, U. S. A. Used with permission.

Source: Eigenbrode et al (2008) National Academy of Sciences, USA. Eigenbrode et al, PNAS

Copyright (c) 2008, National Academy of Sciences, U.S.A. 2008 46

Meishan Drilling Project 2004 c.120 samples Late Permian-Mid Triassic for bulk geochemistry: 87Sr/86Sr, TOC, 13δ carb, 13δorg, 15δorg and detailed lipid biomarkers

Meishan-1 core

drilled near GSSP

Jan 2004Jan 2004

This image has been removed This image has been removed due to copyright restrictions. due to copyright restrictions.

Multiple radiometric ages constrain pace; Ash in bed 25 = 251.4 s 0.3 Ma, Bowring et al, 1998; Revised 252.6 s 0.2 Ma Mundil, 2004; & 252.25 s 0.06 Crowley, Bowring 2008

47

δ15N of Meishan Organic Matter

ve +ve

-90

-85 -4 -2 0 2 4

-ve +ve

-95

90

35-1 35-2

36-3

37-2

-100

dept

h/m

34-12

-105

26-2

34-3 34-1

b24

30-1

-110 22-3

23-4

b24

-115

δ15N kerogen

z P itiPositive l (+3 t +2) i l tvalues (+3 to +2) in late

Permian Beds 6 -24

z Trend to zero or neggative values of δ15N in latest Permian reflects depletion of nitrate/nitrite pool driven by euxinic conditions

z Large swings in E. Triassic may reflect waxing and waning of euxinia

z Predominantly cyanobacterial primary N fixation

Peaks in 2Peaks in 2-MeHI >15%MeHI >15%

Peaks of aryl isoprenoids

48

EARTHRISE Certified Pesticide

FREE

SPIRULINA

Blue-Green Algae Rich in Beta Carotene

Essential Vitamins & Phytonutrients Biologically Grown in the USA

100 TABLETS Net Wt. 50 grams

49

Meishan-1 Isotope Geochemistry


50

Meishan-1 Euxinia/Redox


51

Meishan-1 Microbial Physiologies


52

Hopanoids

The effect of thermal stress on source-rock quality as measured

by hopane stereochemistry

WOLFGANG K. SEIFERT and J.MICHAEL MOLDOWAN

Chevron Oil Field Research Company, P.O. Box 1627, Richmond,

California 94802, U.S.A.


In: A.G. Douglas and J.R. Maxwell, Editors, Advances in Organic Geochemistry, Pergamon Press, Oxford (1980), pp. 229–237

53

Meishan-1 Maturity Parameters


54

Sample with high moretanes, 2-methylmoretanes and 3-methylmoretanes

ms-1-core 36-3 alis 08 June 28 07 2: MRM 25 Channels EI+

69.45 69.85 454.452 > 205.194 100

70.87 72.86 72.06

72.96 73.44 2.71e5 65.64 66.52% 67.78 68.90 74.86

0

74.65 67.09

08 June 28 07 2: MRM 25 Channels EI+ 67.63 440.437 > 205.194 100

66.52 65.64

67.90 68.78 70.83 68.93

69.64

9.96e5 72.15 %

74.01 72.73 73.59 0

08 June 28 07 2: MRM 25 Channels EI+ 68.90 426.421 > 205.194 100 67.78

65.54 70.03 71.08 66.42 69.64

6.65e6

%

0 08 June 28 07 2: MRM 25 Channels EI+

67.78 426.421 > 191.179 100

65.64

68.05 68.90

3.02e7

%


65.64 412.406 > 191.179 100 1.01e8 66.52 %

0 Time 66.00 68.00 70.00 72.00 74.00

55

Sample with low moretanes, 2-methylmoretanes and 3-methylmoretanes

ms05-2b sats 0.7mg 08 June 28 04 2: MRM 25 Channels EI+

69.87

72.42 71.39 70.93

72.96 454.452 > 205.194 100 5.07e5 69.47 73.44

% 65.64 66.54 67.84 68.40 74.70


70.83 440.437 > 205.194 100 67.63 71.14 8.78e5 67.90

%

67.00 66.52 72.10

72.73 68.53 69.45 70.35 73.44 0


68.05

68.93

1.52e6 65.54

% 69.62 65.91 66.86 70.83

0

08 June 28 04 2: MRM 25 Channels EI+

67.78 426.421 > 191.179 100 68.05 1.05e7

%

0 66.37 68.67 69.62

08 June 28 04 2: MRM 25 Channels EI+ 65.64 412.406 > 191.179 100 2.22e7

% 66.04

67.78 0 Time

66.00 68.00 70.00 72.00 74.00

56

0

100

%

4.03e6

65.64 66.52 68.90 67.78

69.85

70.87 72.96 71.20

73.46 74.68

Sample with high moretanes and 2-methylmoretanes

ms-1-core 35-1 alis 08 June 28 09 2: MRM 25 Channels EI+

69.45 454.452 > 205.194


66.54

67.90 68.76

70.83 69.64 71.1472.15

1.88e7

%

0

08 June 28 09 2: MRM 25 Channels EI+

67.78

66.44 69.62 70.03 71.08

65.56 68.93 426.421 > 205.194 100 2.92e7

%


67.78 426.421 > 191.179 100

66.42 65.54

68.05 68.90

1.32e8

%


65.64 412.406 > 191.179 100 4.20e8 66.52 %

0 Time 66.00 68.00 70.00 72.00 74.00

57

Information from Molecular Fossils

A marker for aerobic methanotrophy

2

3

17 21

29

R

3-methylhopane

Collister et al., Organic Geochemistry, 1992

Courtesy Elsevier, Inc., http://www.sciencUsed with permission.

edirect.com.

Summons et al., GCA, 2004

58


Life’s History on Earth Cloud, Holland, Walker Paradigm Prokaryote

World

1

Multi-cell Life

0.1 Humans

(atm

) 0.01 First Eukaryotes (algae)

First InvertebratesGOE

P O

2 (

0.001

0.0001 Oldest ‘compelling’ fossil, stromatolite and C-isotopic evidence for life

0.00001 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0

Time before Present (Ga) 59

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Documents

12.158 Lecture 5 - MIT OpenCourseWare · Methylococcus capsulatus , Bird et al., (1971) •ββ-hopane and ββ-homohopane in . Bacillus acidocaldarius, de Rosa 1973 • Fossil hopanoids