Evolutionary Constraints on Codon and Amino Acid Usage in Two Strains of Human Pathogenic Actinobacteria Tropheryma whipplei
IR@IICB: CSIR-Indian Institute of Chemical Biology, Kolkata
View Archive Info| Field | Value | |
| Title |
Evolutionary Constraints on Codon and Amino Acid Usage in Two Strains of Human Pathogenic Actinobacteria Tropheryma whipplei
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| Creator |
Das, Sabyasachi
Paul, Sandip Dutta, Chitra |
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| Subject |
Structural Biology & Bioinformatics
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| Description |
The factors governing codon and amino
acid usages in the predicted protein-coding sequences
of Tropheryma whipplei TW08/27 and Twist genomes
have been analyzed. Multivariate analysis identifies
the replicational-transcriptional selection coupled
with DNA strand-specific asymmetric mutational
bias as a major driving force behind the significant
interstrand variations in synonymous codon usage
patterns in T. whipplei genes, while a residual intrastrand
synonymous codon bias is imparted by a
selection force operating at the level of translation.
The strand-specific mutational pressure has little
influence on the amino acid usage, for which the
mean hydropathy level and aromaticity are the major
sources of variation, both having nearly equal impact.
In spite of the intracellular lifestyle, the amino
acid usage in highly expressed gene products of
T. whipplei follows the cost-minimization hypothesis.
The products of the highly expressed genes of these
relatively A + T-rich actinobacteria prefer to use the
residues encoded by GC-rich codons, probably due to
greater conservation of a GC-rich ancestral state in
the highly expressed genes, as suggested by the lower
values of the rate of nonsynonymous divergences
between orthologous sequences of highly expressed
genes from the two strains of T. whipplei. Both the
genomes under study are characterized by the presence
of two distinct groups of membrane-associated
genes, products of which exhibit significant differences
in primary and potential secondary structures
as well as in the propensity of protein disorder.
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| Date |
2006
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| Type |
Article
PeerReviewed |
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| Format |
application/pdf
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| Identifier |
http://www.eprints.iicb.res.in/505/1/JOURNAL_OF_MOLECULAR_EVOLUTION%2C_62(_5)%2C_645%2D658_[86].pdf
Das, Sabyasachi and Paul, Sandip and Dutta, Chitra (2006) Evolutionary Constraints on Codon and Amino Acid Usage in Two Strains of Human Pathogenic Actinobacteria Tropheryma whipplei. J Mol Evol, 62 (5). pp. 645-654. |
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| Relation |
htpp://dx.doi.org/10.1007/s00239-005-0164-6
http://www.eprints.iicb.res.in/505/ |
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