5% to 14.47% . The results for R. sphaeroides HGT fell within these ranges but the PXD101 datasheet amount of HGT in CII was significantly higher proportionally (11.66%) compared to that in CI (2.04%). Such
distinct levels of HGT for CI and CII may suggest that both chromosomes play different roles in R. sphaeroides. This observation further confirms that CII has been more flexible in acquiring genes from other species . However, it must be noted that this method of analyzing HGT may not pick up genes that are horizontally transferred between species of similar composition. In addition, although the role of duplicated genes in the majority of bacterial species still remains unclear, the role of gene duplication in the resident genome cannot be underestimated, especially since the majority of these gene duplications are not located within putative HGT regions as seen in R. sphaeroides. Protein divergence and the evolution Selleckchem SB203580 of different COG functions in R. sphaeroides Gene duplications in R. sphaeroides involved in a wide variety of metabolic functions, and these duplications revealed a considerable variation in amino acid divergence within each metabolic function category. For example, protein pairs involved in flagellar assembly
and energy production diverged 60-70%, while protein-pairs involved in photosynthesis and carbon metabolism diverged only 10-30%. These conserved gene homologs may either protect against deleterious changes in either Morin Hydrate copy and consequently result in functional redundancy or may not have been cleared out simply because they are not harmful to the organism. Two sets of flagellar operons and neu operons were located on CI, and most homologous protein pairs had diverged approximately 60-70% of their amino acid sequences. One complete set of flagellar genes (RSP0032-RSP0084) is functional as these genes were expressed in all growth conditions, while the microarray expression of the incomplete flagellar operon (RSP1302-RSP1330) was not detected , and therefore the second set of flagellar genes could be required for surface translocation during biofilm production or in an alternative lifestyle that has
not been identified yet as seen in other organisms [53, 54]. Besides the genes for known functions, the genome of R. sphaeroides contains about 40 duplicate genes encoding hypothetical proteins. About one-half of the total hypothetical protein-pairs diverged ~10-20%, and the other half of the hypothetical protein-pairs diverged ~50-70%. The analyses further revealed that genes involved in groups L (DNA synthesis), N (Cell motility and secretion), U (Intracellular transport), C (Energy production), G (Carbohydrate metabolism), and H (Coenzyme metabolism) were overrepresented among genes evolved by gene duplication, while the number of genes representing other COGs remained low or fairly equal percentage-wise to the number of genes representing those COGs in the overall genome of R. sphaeroides.