Inhibitors of Bacterial Cell Wall Synthesis

In general, penicillins exert thek biological effect, as do the other -lactams, by inhibiting the synthesis of essential structural components of the bacterial cell wall. These components are absent in mammalian cells so that inhibition of the synthesis of the bacterial cell wall stmcture occurs with Htde or no effect on mammalian cell metaboHsm. Additionally, penicillins tend to be kreversible inhibitors of bacterial cell-wall synthesis and are generally bactericidal at concentrations close to thek bacteriostatic levels. Consequently penicillins have become widely used for the treatment of bacterial infections and are regarded as one of the safest and most efficacious classes of antibiotics. 

The inhibitors of bacterial cell-wall synthesis are the beta lactam antibiotics (the penicillins and cephalosporins) (Figure V-l-l), the carbapenems, vancomycin, and aztreonam. 

Inhibitors of bacterial cell wall synthesis include some of the most widely used antibiotics. Also found in this category are several interesting but lesser known compounds with narrower utility. 

L.L. Silver, Novel inhibitors of bacterial cell wall synthesis, Curr. Opin. Microbiol. 2003, 6, 431-438. 

Hasenboehler, A., H. Kneifel, W.A. Koenig, H. ZAhner, and H.J. Zeiler Metabolites of microorganisms. 134. Stenothricin, a New Inhibitor of Bacterial Cell Wall Synthesis. Arch. Microbiol. 99, 307 (1974). 

Vancomycin is bactericidal to most susceptible bacteria at concentrations near its minimum inhibitory concentration (MIC) and is an inhibitor of bacterial cell wall peptidoglycan synthesis, although at a site different from that of j3-lactam antibiotics (Chapter 9). 

Examples of enzyme inhibitors that can be used as drugs Enzyme inhibitors can be used as drugs, inhibiting either intracellular or extracellular reactions. For example, the p-lactam antibiotics, such as penicillin and amoxicillin, act by inhibiting one or more of the enzymes of bacterial cell wall synthesis. 

Selective inhibition of bacterial cell wall synthesis (penicillins, cephalosporins, bacitracin, vancomycin). Following attachment to receptors (penicillinbinding proteins), p-lactam antibiotics inhibit transpeptidation enzymes and thereby block the final stage of peptidoglycan sysnthesis. This action is followed by inactivation of an inhibitor of autolytic enzymes in the bacterial cell wall. Bacitracin and vancomycin inhibit early stages of peptidoglycan synthesis. 

Mechanism of Action Penicillins bind to bacterial cell wall, inhibiting bacterial cell wall synthesis. Therapeutic Effect Inhibits bacterial cell wall synthesis. Beta-lacta-mase inhibitors inhibit the action of bacterial beta-lactamase. Therapeutic Effect Protects the penicillin from enzymatic degradation. 

ANTIBIOTICS 0-LACTAMASE INHIBITORS. The antibacterial effectiveness of penicillins, cephalosporins, and other 0-lactam antibiotics depends on selective acylation and consequently, inactivation, of transpeptidases involved in bacterial cell wall synthesis. This acylating ability is a result of the reactivity of the 0-lactam ring (1). Bacteria that are resistant to 0-lactam antibiotics often produce enzymes called 0-lactamases that inactivate the antibiotics by catalyzing the hydrolytic opening of the 0-lactam... 

O-Linked Oligosaccharides Are Responsible for Different Blood Group Types Specific Inhibitors and Mutants Are Used to Explore the Roles of Glycoprotein Carbohydrates Bacterial Cell Wall Synthesis... 

For the first time, the 1,2,4-oxadiazole ring has been used as a bioisosteres of the ester group in the field of nucleotide chemistry for the production of inhibitors of the bacterial cell-wall synthesis like compound 171.<07JA12642>. 

Bacterial infections are treated with antibiotics. There are many antibiotics available, but they fall into three major groups based on their mode of action inhibitors of bacterial nucleic acid synthesis inhibitors of cell wall synthesis and inhibition of bacterial protein synthesis. Resistance of bacteria to commonly-used antibiotics has become a major problem necessitating the development of new antibiotics. Tuberculosis infection is difficult to treat and requires a combination of at least three different antibiotics. 

Many chemicals can bind to enzymes and either eliminate or drastically reduce their catalytic ability. These chemicals, called enzyme inhibitors, have been used for hundreds of years. When she poisoned her victims with arsenic, Lucretia Borgia was unaware that it was binding to the thiol groups of cysteine amino acids in the proteins of her victims and thus interfering with the formation of disulfide bonds needed to stabilize the tertiary structure of enzymes. However, she was well aware of the deadly toxicity of heavy metal salts like arsenic and mercury. When you take penicillin for a bacterial infection, you are taking another enzyme inhibitor. Penicillin inhibits several enzymes that are involved in the synthesis of bacterial cell walls. 

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