A CLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE HOMOLOG IN BORRELIA-BURGDORFERI AND BORRELIA-HERMSII

A polyreactive monoclonal antibody recognized a 38.5-kDa polypeptide w ith amino-terminal sequence identity to conserved regions of glycerald ehyde-3-phosphate dehydrogenase (GAPDH) in Borrelia burgdorferi, the L yme disease agent, and Borrelia hermsii, an agent of American relapsin g fever, This monoclonal antibody also recognized GAPDH from other pat hogenic spirochetes and other prokaryotes and eukaryotes as well, GAPD H activity was detected in sonicates of both B. burgdorferi and B. her msii but not in live, intact organisms, indicating the possibility of a subsurface localization for the Borrelia GAPDH activity, Degenerate primers constructed from highly conserved regions of gapdh of other pr okaryotes successfully amplified this gene homolog in both B, burgdorf eri and B. hermsii. Nucleic acid and deduced amino acid sequence analy sis of the 838-bp probes for each borrelia indicated 93.9% identity be tween B. burgdorferi and B, hermsii at tile amino acid level, Amino ac id identities of B. burgdorferi and B. hermsii with Bacillus stearothe rmophilus were 59.2% and 58.8%, respectively, Southern hybridization s tudies indicated that the gene encoding GAPDH is located on the chromo some of each borrelia. In other bacterial specks, GAPDH has other func tions in addition to its traditional enzymatic role in the glycolytic pathway, GAPDH may play a similar role in borrelias.