Cephalosporin compounds were first isolated from cultures of Cephalosporium acremonium Researchers at the Sir William Dunn School of Pathology at the University of Oxford isolated cephalosporin C, which had resistance to β-lactamases but was not sufficiently potent for clinical use. The cephalosporin nucleus, 7-aminocephalosporanic acid (7-ACA), was derived from cephalosporin C and proved to be analogous to the penicillin nucleus 6-aminopenicillanic acid. Modification of the 7-ACA side-chains resulted in the development of useful antibiotic agents.
Cephalosporins are bactericidal and have the same mode of action as other beta-lactam antibiotics (such as penicillins). Cephalosporins disrupt the synthesis of the peptidoglycan layer of bacterial cell walls. The peptidoglycan layer is important for cell wall structural integrity. The final transpeptidation step in the synthesis of the peptidoglycan is facilitated by transpeptidases known as penicillin binding proteins (PBPs). PBPs bind to the D-Ala-D-Ala at the end of muropeptides (peptidoglycan precursors) to crosslink the peptidoglycan. beta-lactam antibiotics mimic this site and competitively inhibit PBP crosslinking of peptidoglycan.
Technology data:
1, productivity: 36000~42000u/ml
2, fermentation time: 130-150hrs
3, recovery yield: 75-80%
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