Comparison of the penicillin-binding proteins of different strains of Neisseria gonorrhoeae

Abstract

This study was undertaken to determine if the categorization of Neisseria gonorrhoeae strains into disseminated gonococcal infection (DGI) and non-DGI types was also paralleled by some common characteristic in their penicillinbinding proteins (PBPs [MIC], c0.03 ,ug/ml), (iii) require arginine, hypoxanthine, and uracil for their growth (12), and (iv) can compete highly efficiently for iron (9). It was also demonstrated that serum resistance is associated with the possession of a principal outer membrane protein (POMP) of characteristic subunit molecular weight and antigenicity (5). The differential penicillin susceptibility of isolates from uncomplicated and disseminated gonococcal infections (DGI and non-DGI) led us to speculate that the DGI character might also be paralleled by the presence or absence of some specific penicillinbinding proteins (PBPs) in the inner membrane of N. gonorrhoeae. We have, therefore, used techniques similar to those described by Spratt (13) munosorbent assay, was performed using purified gonococcal POMP from strain 7122 as described earlier (2, 4, 5). The serum bactericidal activities and auxotyping (5, 6, 11) of the N. gonorrhoeae strains used were performed in the laboratories of K.

Properties of penicillin-binding proteins in Neisseria gonorrhoeae

“…An alteration in the cell envelope, such as that described by Sparling and co-workers (4,19), may contribute to resistance as well. The inability to explain the consistently greater susceptibility of those disseminated gonococcal infection strains examined in both this study and in the study of Nolan and Hildebrandt (15) (20,21). Gonococcal PBP 1 may, like E. coli PBP lb (23), be involved in cell wall expansion and in crosslinking peptidoglycan side chains.…”

“…Some of these PBPs have been identified either with penicillin-sensitive enzymes involved in peptidoglycan synthesis (6,12,22,23) or, when enzyme specificity remains undefined, with a process such as cell septation or cylindrical growth (21,22). Neisseria gonorrhoeae, a gram-negative coccus, possesses PBPs as well (15,16). Little is known, however, of the functions of individual gonococcal PBPs.…”

Penicillin-binding proteins of penicillin-susceptible and intrinsically resistant Neisseria gonorrhoeae

“…Similarly, preparations from the taxonomically related species Neisseria menigitidis and Neisseria sicca yielded PBP patterns similar to the pattern of gonococci. We did not observe strain-to-strain variation in the PBP pattern (16); differences in the details of the methodologies used (growth of cells, electrophoretic procedure) may account for this.…”

“…Previous reports in the literature (16,20) suggested that the PBPs of gonococci may vary from strain to strain. In contrast, we found that the PBP patterns of the strains that were routinely used were highly reproducible.…”

The different shapes of cocci

“…The localization of this protein as well as its activity in the absence of antibiotics remains unknown. PBPs from other spherical cocci have not been localized, but the fact that Neisseria meningitidis or Neisseria gonorrhoeae have only four described PBPs (Nolan & Hildebrandt, 1979;Barbour, 1981;Stefanova et al, 2004), which include only one representative of HMW class A (PBP1) and one of HMW class B (PBP2) PBPs, may indicate that these species also have only one cell wall synthetic machinery.…”