[Mechanisms of resistance to beta-lactam antibiotics].
Beta-lactam antibiotics share the structural feature of a beta-lactam ring. This feature is responsible for inhibition of bacterial cell wall synthesis. The target molecules are peptidoglycan cross-linking enzymes (e.g. transpeptidases and carboxypeptidases) which can bind beta-lactam antibiotics (penicillin binding proteins, PBP). Bacterial cell death is initiated by beta-lactam antibiotic-triggered release of autolytic enzymes. In contrast to gram-positive bacteria (absence of an outer membrane) the antibiotic has to penetrate through porins of the outer membrane of gram-negative bacteria before touching PBP's. Bacterial resistance to beta-lactam antibiotics includes modification of porins (permeability barrier) and of targets (low affinity of PBP's for the drug), production of inactivating enzymes (beta-lactamases) and inhibition of release of autolytic enzymes. Moreover, bacteria have developed sophisticated genetic mechanisms to adapt to treatments with novel beta-lactam antibiotics. To allow successful antibiotic treatment of bacterial infection in the future, knowledge about antibiotic resistance mechanisms is required.
Heesemann
J
J
Institut für Hygiene und Mikrobiologie, Universitätsklinik, Luitpold-Krankenhaus, Würzburg.
D000596:Amino Acids / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000648:ultrastructure; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000187:drug effects / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects; D004352:Drug Resistance, Microbial / Q000235:genetics / Q000502:physiology; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase / Q000187:drug effects / Q000378:metabolism; D046915:Penicillin-Binding Proteins; D010406:Penicillins / Q000378:metabolism; D010458:Peptidyl Transferases; D018272:Porins / Q000378:metabolism; D011487:Protein Conformation; D047090:beta-Lactams
D000596:Amino Acids; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D010406:Penicillins; D018272:Porins; D047090:beta-Lactams; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase
Resistenzmechanismen gegen Betalaktamantibiotika.