REVIEW

Molecular evolution of methanogens based on their metabolic facets

  • P. CHELLAPANDI
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  • Department of Bioinformatics, Centre for Excellence in School of Life Sciences, Bharathidasan University, Tiruchirappalli-620024, Tamil Nadu, India

Received date: 22 Mar 2011

Accepted date: 30 Apr 2011

Published date: 01 Dec 2011

Copyright

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg

Abstract

The information provided by completely sequenced genomes of methanogens can yield insights into a deeper molecular understanding of evolutionary mechanisms. This review describes the advantages of using metabolic pathways to clarify evolutionary correlation of methanogens with archaea and prokaryotes. Metabolic trees can be used to highlight similarities in metabolic networks related to the biology of methanogens. Metabolic genes are among the most modular in the cell and their genes are expected to travel laterally, even in recent evolution. Phylogenetic analysis of protein superfamilies provides a perspective on the evolutionary history of some key metabolic modules of methanogens. Phage-related genes from distantly related organisms typically invade methanogens by horizontal gene transfer. Metabolic modules in methanogenesis are phylogenetically aligned in closely related methanogens. Reverse order reactions of methanogenesis are achieved in methylotrophic methanogens using metabolic and structural modules of key enzymes. A significant evolutionary process is thought to couple the utilization of heavy metal ions with energetic metabolism in methanogens. Over 30 of methanogens genomes have been sequenced to date, and a variety of databases are being developed that will provide for genome annotation and phylogenomic analysis of methanogens. Into the context of the evolutionary hypothesis, the integration of metabolomic and proteomic data into large-scale mathematical models holds promise for fostering rational strategies for strain improvement.

Cite this article

P. CHELLAPANDI . Molecular evolution of methanogens based on their metabolic facets[J]. Frontiers in Biology, 2011 , 6(6) : 490 -503 . DOI: 10.1007/s11515-011-1154-2

Acknowledgements

The author kindly acknowledges the University Grants Commission, New Delhi, India, for financial assistance (32-559/2006) to carry out work described in this review.
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