Journal Article

PreJuSER-6219

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Macromolecular composition of Palaeozoic scolecodonts: insights into the molecular taphonomy of zoomorphs

Dutta, S. ; Hartkopf-Fröder, C. ; Mann, U.FZJ* ; Wilkes, H. ; Brocke, R. ; Bertram, N.

2010
Wiley-Blackwell Oxford [u.a.]

This record in other databases:  

Please use a persistent id in citations: doi:10.1111/j.1502-3931.2009.00193.x

Abstract: Biogeochemistry and molecular taphonomy of biopolymers of marine zoomorphs are poorly known. In order to obtain insights into this issue we report on the biogeomacromolecular composition of hand-picked, well-preserved scolecodonts of Ordovician, Silurian and Devonian age using micro-Fourier transform infrared (micro-FTIR) spectroscopy, Curie point pyrolysis-gas chromatography-mass spectrometry (Cupy-GC-MS) and tetramethylammonium hydroxide (TMAH)-assisted thermochemolysis-GC-MS. The present study reveals that scolecodonts are composed of both aliphatic and aromatic moieties. The micro-FTIR spectra of scolecodonts are characterized by aliphatic CHx (3000–2800 and 1460–1450/cm) and CH3 (1375/cm) absorptions and aromatic C=C (1560–1610/cm) and CH (3050/cm and 700–900/cm) absorptions. The major pyrolysis products from the scolecodonts include aromatic hydrocarbons such as alkylbenzenes, alkylnaphthalenes and alkylphenols. Aliphatic hydrocarbons are represented by a homologous series of n-alkenes and n-alkanes. The compounds released upon thermochemolysis with TMAH are saturated and unsaturated fatty acids (as their methyl esters), n-alkenes/alkanes and aromatic acids (as their methyl esters). No protein/amino acid-derived compounds have been recognized in the pyrolysates or in the thermochemolysates, and it is concluded that protein/amino acid-related compounds, which are commonly found in the jaws of extant polychaetes, were destroyed due to diagenetic processes. Obviously, excellent morphological preservation and low thermal alteration are not paralleled by a similar degree of chemical preservation. □Biogeomacromolecules, micro-FTIR, pyrolysis-GC-MS, scolecodonts, thermochemolysis-GC-MS.

Keyword(s): Biogeomacromolecules (auto) ; micro-FTIR (auto) ; pyrolysis-GC-MS (auto) ; scolecodonts (auto) ; thermochemolysis-GC-MS (auto)

Note: We would like to thank Forschungszentrum Julich for financial support. SD is grateful to IIT Bombay for providing infrastructural facilities. Mrs K. Witte (Aachen University of Applied Sciences, Germany) is acknowledged for providing access to the micro-FTIR instrument. The authors are grateful to Mats Eriksson and an anonymous reviewer for valuable comments. We gratefully acknowledge Richard M. Fuchs (Harrison, OH, USA), Axel Munnecke (GeoZentrum Nordbayern, Germany) and Jan Bohaty (University of Cologne, Germany) for providing the samples from the Upper Ordovician of Ohio, the Silurian of Gotland and from the Devonian of the Eifel Mountains respectively.

---

Research Program(s):

1. Terrestrische Umwelt (P24)

Appears in the scientific report 2010

---