Influence of genomic G + C content on average amino-acid composition of proteins from 59 bacterial species
The amino-acid composition of 23 490 proteins from 59 bacterial species was analyzed as a function of genomic G + C content. Observed amino-acid frequencies were compared with those expected from a neutral model assuming the absence of selection on average protein composition. Integral membrane prot...
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Published in | Gene Vol. 205; no. 1; pp. 309 - 316 |
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Main Author | |
Format | Journal Article |
Language | English |
Published |
Netherlands
Elsevier B.V
31.12.1997
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | The amino-acid composition of 23 490 proteins from 59 bacterial species was analyzed as a function of genomic G + C content. Observed amino-acid frequencies were compared with those expected from a neutral model assuming the absence of selection on average protein composition. Integral membrane proteins and non-integral membrane proteins were analyzed separately. The average deviation from this neutral model shows that there is a selective pressure increasing content in charged amino acids for non-integral membrane proteins, and content in hydrophobic amino acids for integral membrane proteins. Amino-acid frequencies were greatly influenced by genomic G + C content, but the influence was found to be often weaker than predicted. This may be evidence for a selective pressure, maintaining most amino-acid frequencies close to an optimal value. Concordance between the genetic code and protein composition is discussed in the light of this observation. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0378-1119 1879-0038 |
DOI: | 10.1016/S0378-1119(97)00403-4 |