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Glycopeptide antibiotics are a class of drugs of microbial origin that are composed of glycosylated cyclic or polycyclic nonribosomal peptides.Significant glycopeptide antibiotics include the anti-infective antibiotics vancomycin, teicoplanin, telavancin, ramoplanin, avoparcin and decaplanin, corbomycin, complestatin and the antitumor antibiotic bleomycin.
Bacitracin is a polypeptide antibiotic derived from a bacterium, Bacillus subtilis, and acts against bacteria through the inhibition of cell wall synthesis. [6] It does this by inhibiting the removal of phosphate from lipid compounds, thus deactivating its function to transport peptidoglycan; the main component of bacterial cell membranes, to the microbial cell wall.
Lipid II must translocate across the cell membrane to deliver and incorporate its disaccharide-pentapeptide "building block" into the peptidoglycan mesh. Lipid II is the target of several antibiotics. A number of analogous compounds are produced via a similar pathway in some bacteria, giving rise to cell wall modifications.
Cephalosporins are bactericidal and, like other β-lactam antibiotics, disrupt the synthesis of the peptidoglycan layer forming the bacterial cell wall. The peptidoglycan layer is important for cell wall structural integrity. The final transpeptidation step in the synthesis of the peptidoglycan is facilitated by penicillin-binding proteins ...
The moenomycin family functions as an antibiotic by reversibly binding bacterial transglycosylases, essential enzymes that catalyze the extension of the glycan chain of the cell wall to form a stable peptidoglycan layer. The moenomycins mimic and thus compete with the natural substrate of the enzyme, inhibiting growth of the cell wall.
Since peptidoglycan is also lacking in L-form bacteria and in mycoplasmas, both are resistant against penicillin. Other steps of peptidoglycan synthesis can also be targeted. The topical antibiotic bacitracin targets the utilization of C55-isoprenyl pyrophosphate. Lantibiotics, which includes the food preservative nisin, attack lipid II. [36]
BEIJING (Reuters) -No one can stop China's "reunification" with Taiwan, Chinese President Xi Jinping said in his New Year's speech on Tuesday, laying down a clear warning to what Beijing regards ...
Bacteria constantly remodel their peptidoglycan cell walls, simultaneously building and breaking down portions of the cell wall as they grow and divide. During the last stages of peptidoglycan biosynthesis, uridine diphosphate- N -acetylmuramic acid pentapeptide (UDP-MurNAc) is formed in which the fourth and fifth amino acids are both D -alanyl ...