Penicillin-binding proteins in Leptospira interrogans

The Leptospira interrogans ponA and pbpB genes were isolated and characteri zed. ponA and pbpB encode the penicillin-binding proteins (PBPs) 1 and 3, r espectively. There is little sequence variation between the PBP genes from two L, interrogans strains (serovar icterohaemorrhagiae strain Verdun and s erovar pomona strain RZ11). The deduced L, interrogans PBP 1 and PBP 3 prot ein sequences from the two strains shared over 50% similarity to homologous proteins from Escherichia coli, It was demonstrated for strain Verdun that ponA and pbpB are transcribed individually from their own promoter. The po nA and pbpB genes from both strains are separated by 8 to 10 kb and oriente d such that their transcription is convergent. The L. interrogans PBP 1 and PBP 3 proteins were synthesized in E, coil and were modified with ampicill in using a digoxigenin-ampicillin conjugate. These data show that both gene s encode functional PBPs.