title: Amino acid variation in cellular processes in 108 bacterial proteomes.
abstract: We have analysed 108 bacterial proteomes in the KEGG database to explore the variation of amino acid composition with respect to protein function. The ratio between the observed amino acid composition and that predicted based on mononucleotide composition was calculated for each functional category. This indicated whether the compositional variation arose from mutation or selection pressure. The results showed that charged amino acids (Lys, Arg and Glu), were found more frequently than expected in proteins involved in genetic information processing (i.e. transcription, translation, etc.) Similarly, in the proteins involved in processing environmental information (e.g. signal transduction), the hydrophobic amino acid Leu was found in excess of values expected from the base composition in the genes.
authors.affiliation: Department of Crystallography and Biophysics, University of Madras, Guindy Campus, 600025 Chennai, India.
authors.forename: Devarajan
authors.initials: D
authors.lastname: Bharanidharan
authors.forename: Namasivayam
authors.initials: N
authors.lastname: Gautham
mesh_terms: D019943:Amino Acid Substitution; D000596:Amino Acids / Q000032:analysis*; D001120:Arginine / Q000032:analysis; D001419:Bacteria / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D001482:Base Composition; D019295:Computational Biology; D005798:Genes, Bacterial; D016680:Genome, Bacterial; D018698:Glutamic Acid / Q000032:analysis; D007930:Leucine / Q000032:analysis; D008239:Lysine / Q000032:analysis; D009154:Mutation; D014176:Protein Biosynthesis; D020543:Proteome; D012641:Selection, Genetic; D015398:Signal Transduction; D014158:Transcription, Genetic
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D020543:Proteome; D018698:Glutamic Acid; D001120:Arginine; D007930:Leucine; D008239:Lysine