TY - JOUR
T1 - Bacterial genome adaptation to niches
T2 - Divergence of the potential virulence genes in three Burkholderia species of different survival strategies
AU - Kim, H. Stanley
AU - Schell, Mark A.
AU - Yu, Yan
AU - Ulrich, Ricky L.
AU - Sarria, Saul H.
AU - Nierman, William C.
AU - DeShazer, David
PY - 2005/12/7
Y1 - 2005/12/7
N2 - Background: Two closely related species Burkholderia mallei (Bm) and Burkholderia pseudomallei (Bp) are serious human health hazards and are potential bio-warfare agents, whereas another closely related species Burkholderia thailandensis (Bt) is a non-pathogenic saprophyte. To investigate the genomic factors resulting in such a dramatic difference, we first identified the Bm genes responsive to the mouse environment, and then examined the divergence of these genes in Bp and Bt. Results: The genes down-expressed, which largely encode cell growth-related proteins, are conserved well in all three species, whereas those up-expressed, which include potential virulence genes, are less well conserved or absent notably in Bt. However, a substantial number of up-expressed genes is still conserved in Bt. Bm and Bp further diverged from each other in a small number of genes resulting from unit number changes in simple sequence repeats (ssr) in the homologs. Conclusions: Our data suggest that divergent evolution of a small set of genes, rather than acquisition or loss of pathogenic islands, is associated with the development of different life styles in these bacteria of similar genomic contents. Further divergence between Bm and Bp mediated by ssr changes may reflect different adaptive processes of Bm and Bp fine-tuning into their host environments.
AB - Background: Two closely related species Burkholderia mallei (Bm) and Burkholderia pseudomallei (Bp) are serious human health hazards and are potential bio-warfare agents, whereas another closely related species Burkholderia thailandensis (Bt) is a non-pathogenic saprophyte. To investigate the genomic factors resulting in such a dramatic difference, we first identified the Bm genes responsive to the mouse environment, and then examined the divergence of these genes in Bp and Bt. Results: The genes down-expressed, which largely encode cell growth-related proteins, are conserved well in all three species, whereas those up-expressed, which include potential virulence genes, are less well conserved or absent notably in Bt. However, a substantial number of up-expressed genes is still conserved in Bt. Bm and Bp further diverged from each other in a small number of genes resulting from unit number changes in simple sequence repeats (ssr) in the homologs. Conclusions: Our data suggest that divergent evolution of a small set of genes, rather than acquisition or loss of pathogenic islands, is associated with the development of different life styles in these bacteria of similar genomic contents. Further divergence between Bm and Bp mediated by ssr changes may reflect different adaptive processes of Bm and Bp fine-tuning into their host environments.
UR - http://www.scopus.com/inward/record.url?scp=29244477827&partnerID=8YFLogxK
U2 - 10.1186/1471-2164-6-174
DO - 10.1186/1471-2164-6-174
M3 - Article
C2 - 16336651
AN - SCOPUS:29244477827
SN - 1471-2164
VL - 6
JO - BMC Genomics
JF - BMC Genomics
M1 - 174
ER -