Open AccessMicrobiological Properties of a New Cephalosporin, BL-S 339: 7-(Phenylacetimidoyl-aminoacetamido)-3-(2-Methyl-1, 3,4-Thiadiazol-5-Ylthiomethyl)Ceph-3-em-4-Carboxylic Acid
Author(s) -
M. Misiek,
T. A. Pursiano,
F. Leitner,
K. E. Price
Publication year - 1973
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.3.1.40
Subject(s) - cephalosporin , microbiology and biotechnology , enterobacter , serratia marcescens , klebsiella pneumoniae , antibacterial activity , bacteria , escherichia coli , serratia , agar plate , agar dilution , nutrient agar , klebsiella , agar , biology , antibiotics , minimum inhibitory concentration , biochemistry , pseudomonas , genetics , gene
BL-S 339 is a new broad-spectrum, parenterally effective cephalosporin whose expression of antibacterial activity in vitro is markedly affected by the nature of the assay medium. When assayed in nutrient agar, BL-S 339 was more active than cephalothin against strains ofDiplococcus pneumoniae, Streptococcus pyogenes, Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, Enterobacter , and indole-positiveProteus sp. However, when assayed in Mueller-Hinton medium, its activity, especially against gram-negative bacteria, was reduced substantially, whereas the activity of cephalothin was virtually unaffected by the assay medium. The in vivo activity of BL-S 339 correlated well with its activity in nutrient agar; when administered subcutaneously to mice, it was therapeutically more efficacious than cephalothin in infections caused by both gram-positive and gram-negative bacteria. When BL-S 339 was administered intramuscularly to mice, the concentrations achieved in the blood were three times those achieved with cephalothin. BL-S 339 was bound to human serum proteins to the same extent as cephalothin. Recovery of BL-S 339 in the urine within the 24-hr period after intramuscular administration to rats was three times that of cephalothin.