This method exploits compositional biases to determine potential HGT areas where abnormal (HGT) areas are identified as those that are higher than a threshold value, a value that is calculated using the sequence structure of the input genome among other factors. This

software was used to BAY 80-6946 chemical structure determine the areas of possible HGT and the levels of HGT on CI and CII independently. The genes present within these regions were additionally identified. Artemis [41] was used to view the Alien-Hunter output. Results Extent of gene duplications in R. sphaeroides Of the total 4242 protein coding genes in its genome, a total of 1247 genes (29.4% of its genome) exist in multiple copies in the R. sphaeroides genome. Gene homologs are present in different copies reflecting the diversity of gene multiplication. Numbers of genes with 2, 3, 4 and 5 and more (≥ 5) copies were 468, 183, 152, and 444, respectively. Approximately 73% of the total gene homologs represent two classes, genes with two copies (37.5%; 234 protein pairs) and genes with ≥ 5 copies (35.6%). Genes with ≥ 5 copies BAY 73-4506 price represent various types of functions, for example, ABC type transporters, families of transcriptional factors, and cell-signaling response regulators (data not shown). If genes that are present in more than two copies were to be selected, determining

the lineage of such genes becomes functionally more complex, especially as many such genes are also present within multiple gene families. Moreover, the genes in these families can be analogous instead of homologous, meaning that they are similar due to function rather than origin. As such, further analysis was carried out only on genes which were identified as duplicate protein pairs as listed in Additional file 1. The mean amino acid identity of the protein-pairs was 46.0% and the standard deviation was 19.5% with a maximum amino acid identity of 99%. Gene homologs are dispersed either within each replicon or between replicons in the genome of R. sphaeroides

as shown in Figure 1. Of the total 234 duplicate-genes, 196 gene duplications (83.8%) were chromosomal and 38 gene duplications (16.2%) were dispersed between chromosome and plasmid or between plasmids. Of chromosomal gene duplications, intra-chromosomal and inter-chromosomal Fluorouracil cost gene duplications were 131 (56.0%) and 65 (27.8%), respectively. Of the 131 intra-chromosomal gene duplications, 118 (50.4%) and 13 (5.5%) gene homologs were located within CI and CII, respectively. Taking the sizes of the two chromosomes into account (CI is three times larger than the size of CII); the number of gene duplications found within CI was significantly higher than the number of gene duplications found within CII. Approximately 16.2% of gene duplications involve plasmids where 9.8% of the total gene duplications involve plasmids and chromosomes while 6.4% of the total genes duplications were solely between plasmids.