Functional classes in the three domains of life

Item Type:	Article
Title:	Functional classes in the three domains of life
Creators Name:	Andrade, M.A. and Ouzounis, C. and Sander, C. and Tamames, J. and Valencia, A.
Abstract:	The evolutionary divergence among the three major domains of life can now be addressed through the first set of complete genomes from representative species. These model species from the three domains of life, Haemophilus influenzae for Bacteria, Saccharomyces cerevisiae for Eukarya, and Methanococcus jannaschii for Archaea, provide the basis for a universal functional classification and analysis. We have chosen 13 functional classes and three superclasses (ENERGY, COMMUNICATION and INFORMATION) as global descriptors of protein function. Compositional comparison of the three complete genomes reveals that functional classes are ubiquitous yet diverse in the three domains of life. Proteins related with ENERGY processes are generally represented in all three domains, while those related with COMMUNICATION represent the most distinctive functional feature of each single domain. Finally, functions related with INFORMATION processing (translation, transcription, and replication) show a complex behaviour. In Archaea, proteins in this superclass are related with proteins in either Eukarya or Bacteria, as recognized previously. The distribution of functional classes in the three domains accurately reflects the principal characteristics of cellular life forms.
Keywords:	Genome Comparison, Functional Classes, Haemophilus Influenzae, Saccharomyces Cerevisiae, Methanoccus Jannaschii, Archaea
Source:	Journal of Molecular Evolution
ISSN:	0022-2844
Publisher:	Spriner
Volume:	49
Number:	5
Page Range:	551-557
Date:	November 1999
Official Publication:	https://doi.org/10.1007/PL00006576
PubMed:	View item in PubMed

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