title: Formadicins, new monocyclic beta-lactam antibiotics of bacterial origin. I. Taxonomy, fermentation and biological activities.
abstract: A Gram-negative bacterium produces new monocyclic beta-lactam antibiotics with a formylamino substituent, named formadicins A, B, C and D. The producing bacterium was taxonomically characterized and designated as Flexibacter alginoliquefaciens sp. nov. YK-49. Formadicins have narrow antibacterial spectra. They are highly active against some species of Pseudomonas, Proteus and Alcaligenes. Of the four, formadicin C shows the most potent antibacterial activity. Several amino acids such as glycine, D-alanine and D-leucine were antagonistic against formadicins. Formadicins, especially formadicins A and C having the formylamino substituent bound to the 3-position of a beta-lactam nucleus, were highly resistant to hydrolysis by various types of beta-lactamases. Formadicins A and C showed affinity for penicillin-binding proteins (PBPs) 1A and 1B in Pseudomonas aeruginosa IFO 3080, but formadicin B and nocardicin A showed affinity only for PBP 1B. Formadicins A and C did not lyse Escherichia coli LD-2 solely at their MICs, but when combined with mecillinam each induced a rapid lysis of this organism.
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D001426:Bacterial Proteins; D001433:Bacteriolysis / Q000187:drug effects; D002352:Carrier Proteins / Q000378:metabolism; D041964:Cytophagaceae / Q000145:classification* / Q000378:metabolism; D004355:Drug Stability; D005285:Fermentation; D006602:Hexosyltransferases; D007769:Lactams; D002267:Muramoylpentapeptide Carboxypeptidase / Q000378:metabolism; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D001618:beta-Lactamases / Q000494:pharmacology; D047090:beta-Lactams
chemical_list: D000596:Amino Acids; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D007769:Lactams; D046915:Penicillin-Binding Proteins; D047090:beta-Lactams; C046891:formadicin; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase; D001618:beta-Lactamases