Peptidoglycan determines the overall cellular shape, serves as attachment site for virulence factors and adhesins, aids bacteria in undergoing morphological transformations in response to different stress-related factors, and its eventual fragility or instability may lead to cell lysis and death ( HГ¶ltje, 1998 Nanninga, 1998 ). The bacterial peptidoglycan, a three-dimensional, net-like mesh which lines the exterior of the cell membrane, not only must be synthesized in a timely manner during the cell cycle but also protects bacteria from osmotic shock. Penicillin binding proteins, resistance, cell cycle Introduction In this review, we discuss structural, functional and biological features of such enzymes which, albeit having initially been identified several decades ago, are now being aggressively pursued as highly attractive targets for the development of novel antibiotherapies. In addition, the recent publication of high-resolution structures of PBPs from pathogenic organisms have shed light on the complex intertwining of drug resistance and cell division processes. The increasing incidence of ОІ-lactam resistant microorganisms, coupled to progress made in genomics, genetics and immunofluorescence microscopy techniques, have encouraged the intensive study of PBPs from a variety of bacterial species. Penicillin-binding proteins (PBPs), membrane-associated macromolecules which play key roles in the cell wall synthesis process, have been exploited for over 70 years as the targets of the highly successful ОІ-lactam antibiotics. Bacterial cell division and daughter cell formation are complex mechanisms whose details are orchestrated by at least a dozen different proteins.

Ahmet hulusi kuran tefsiri