Comparative Genomic Analysis of Food-Originated Coagulase-Negative Staphylococcus: Analysis of Conserved Core Genes and Diversity of the Pan-Genome.

To shed light on the genetic differences among food-originated coagulase-negative (CNS), we performed pan-genome analysis of five species: (two strains), (two strains), (three strains), (two strains), and (one strain). The pan-genome size increases with each new strain and currently holds about 4,500 genes from 10 genomes. Specific genes were shown to be strain dependent but not species dependent. Most specific genes were of unknown function or encoded restriction-modification enzymes, transposases, or prophages. Our results indicate that unique genes have been acquired or lost by convergent evolution within individual strains.