Evaluation of intraspecies genetic variation within the 60 kDa heat-shock protein gene (groEL) of Bartonella species

A phylogenetic investigation was done on the members of the genus Bartonell a, based on the DNA sequence analysis of the groEL gene, which encodes the 60 kDa heat-shock protein GroEL. Nucleotide sequence data were determined f or a near full-length fragment (1368 bp) of the groEL gene of the establish ed Bartonella species and used to infer intraspecies phylogenetic relations hips. Phylogenetic trees were inferred from multiple sequence alignments by using both distance and parsimony methods, which demonstrated an architect ure composed of six well-supported lineages. The results are consistent wit h relationships deduced from recent sequence analysis studies based upon ci trate synthase (gltA) sind previously observed genotypic and phenotypic cha racteristics; however, they showed greater statistical support at the intra genus level. This suggests that groEL may be a more robust tool for phyloge netic analysis of Bartonella lineages.