Penicillin-binding protein 1A (PBP1A) (TP0705)

TP0705 is a critical enzyme in Treponema pallidum, the spirochete bacterium responsible for syphilis [19, 21]. It is identified as Penicillin-binding protein 1A (PBP1A), also known as mrcA, and plays a vital role in the biosynthesis of the bacterial cell wall [26, 38]. The protein functions as both a glycosyltransferase and a transpeptidase, catalyzing the polymerization and cross-linking of peptidoglycan strands [1, 20]. As a member of the penicillin-binding protein family, TP0705 is a primary therapeutic target for beta-lactam antibiotics, such as penicillin G and ceftriaxone [19, 22]. These drugs bind to the enzyme's active site, inhibiting its transpeptidase activity and leading to cell wall defects and bacterial lysis [19, 21]. Although T. pallidum has remained largely susceptible to penicillin for decades, researchers monitor TP0705 for mutations that could potentially confer resistance [19, 22]. Additionally, TP0705 is a key genetic locus used in multilocus sequence typing (MLST) to differentiate and track the global spread of various T. pallidum strains [7, 13, 27]. Understanding the structure and variation of this protein is essential for both clinical diagnostics and the development of future syphilis vaccines [14, 36].

Other names

mrcATP_0705PBP1APenicillin-binding protein 1TPANIC_0705

Inhibition of peptidoglycan cross-linking (transpeptidation) and polymerization (glycosyltransfer) during cell wall synthesis.