Proteins encoded by a 9.5-kb DNA segment, termed the region of difference (RD), of Mycobacterium tuberculosis have been demonstrated to be important in bacterial virulence, vaccine development and the design of diagnostic reagents.
Moreover, edges located in the overlapping region of difference images are deteriorated due to insignificant gradient values of that region.
Edges in the overlapping region of difference image also experience size, shape, and positional variations than that in current frame (as shown in Figure 1).
TB51A, TB15.3, CFP-10 and ESAT-6 are proteins that are encoded on the region of difference (RD-1) domain of the Mycobacterium tuberculosis genome.
Our experiments were in agreement with previous studies that described few major genomic insertion or deletion events between the two strains, other than the RvD2 region of difference.
Recently, a group of insertions/deletions (also known as region of difference or RD) that are unique event polymorphisms and define a robust phylogeny were described.
In addition to the drug resistance genes associated with Tn916, ICESsuBM4072 also carries genes encoding the tetracycline resistance protein TetO (SSUBM407_0954), erythromycin ribosome methylase ErmB (SSUBM407_0952) and dihydrofolate reductase (SSUBM407_0957), in a region of difference located elsewhere on the element.
Genes positively regulated by PhoP include those required for hypoxia adaptation, genes involved in aerobic/anaerobic respiration, genes within the Region of Difference 1 (RD1), genes encoding stress proteins and genes involved in lipid metabolism.
This has led to the use of smaller antigens encoded in the region of difference 1 (RD1) portion of the genome of M.tb, which is absent in BCG-strains [23].
The only large scale region of difference is associated with the 89 kb putative PI that is present in the two sequenced ST7 strains [7], and absent in P1/7.
Comparing genomic differences between the strains using CGH microarray analysis confirmed the recently reported sequence similarity [37], [38] along with the RvD2 region of difference present only in H37Ra (Table 1).
