Phylogenetic Analysis of Coxsackie B Viruses Reveals Genomic Plasticity and Adaptation as Studied by Codon Usage Patterns

Coxsackie B viruses (CVB) are associated with serious illnesses in humans. In this study, the patterns of synonymous codon usage in CVB have been studied through multivariate statistical methods. Effective number of codons (ENC) indicates that the overall extent of codon usage bias in CVB is not significant. The relative dinucleotide abundances suggest that codon usage bias in CVB genomes is influenced by underlying biases of dinucleotide frequencies. The distribution of CVB ORFs along the plane defined by the first two axes of correspondence analysis (COA) showed that different genotypes, as well as strains known to infect different cell types, are located at different places in the plane suggesting that CVB codon usage is reflecting an evolutionary process. The results of these studies suggest that CVB genomic biases are the result of co-evolution of translation adaptation to different cell environments and probably the need to escape anti-viral cell defenses.