Antimicrobial activity of Ro 19-5247 (T-2525), a new oral cephalosporin, tested against 7,745 recent clinical isolates

New insights into cheddar cheese microbiota-metabolome relationships revealed by integrative analysis of multi-omics data

Cheese microbiota and metabolites and their inter-relationships that underpin specific cheese quality attributes remain poorly understood. Here we report that multi-omics and integrative data analysis (multiple co-inertia analysis, MCIA) can be used to gain deeper insights into these relationships and identify microbiota and metabolite fingerprints that could be used to monitor product quality and authenticity. Our study into different brands of artisanal and industrial cheddar cheeses showed that Streptococcus, Lactococcus and Lactobacillus were the dominant taxa with overall microbial community structures differing not only between industrial and artisanal cheeses but also among different cheese brands. Metabolome analysis also revealed qualitative and semi-quantitative differences in metabolites between different cheeses. This also included the presence of two compounds (3-hydroxy propanoic acid and O-methoxycatechol-O-sulphate) in artisanal cheese that have not been previously reported in any type of cheese. Integrative analysis of multi-omics datasets revealed that highly similar cheeses, identical in age and appearance, could be distinctively clustered according to cheese type and brand. Furthermore, the analysis detected strong relationships, some previously unknown, which existed between the cheese microbiota and metabolome, and uncovered specific taxa and metabolites that contributed to these relationships. These results highlight the potential of this approach for identifying product specific microbe/metabolite signatures that could be used to monitor and control cheese quality and product authenticity.

Ceftibuten (7432-S, SCH 39720): comparative antimicrobial activity against 4735 clinical isolates, beta-lactamase stability and broth microdilution quality control guidelines

The antimicrobial activity of ceftibuten, a new oral cephalosporin, was evaluated using 4735 clinical bacterial isolates processed at four medical centers. Ceftibuten inhibited nearly 92% of all Enterobacteriaceae (less than or equal to 8.0 micrograms/ml), thereby being markedly superior to cefixime which inhibited 78.7% at less than or equal to 1.0 microgram/ml and cefuroxime which inhibited 45.1% at less than or equal to 2.0 micrograms/ml. Pseudomonads and staphylococci were not within the spectrum of activity of ceftibuten. Ceftibuten was found to be very stable in the presence of five commonly occurring beta-lactamases of both the chromosomal-mediated (P99, K1) and plasmid-mediated (CARB-2, OXA-1, TEM-1) types. Only Type Ia (P99) beta-lactamase was significantly inhibited by ceftibuten. On the basis of results of a ceftibuten MIC quality control study conducted in five laboratories, a quality control range of 0.12 to 0.5 microgram/ml is recommended for the Escherichia coli ATCC 25922 strain.

Antimicrobial activity of MDL 19,592: an oral cephalosporin

MDL 19,592, a semisynthetic oral cephalosporin, has an antimicrobial spectrum principally directed against Gram-positive cocci (MIC50, 0.25-4 micrograms/ml), Branhamella catarrhalis (MIC50, 1-2 micrograms/ml), and pathogenic Neisseria spp. such as meningococci (MIC50, 4 micrograms/ml). Enterobacteriaceae, enterococci, Pseudomonas spp., Corynebacterium jeikeium, and Acinetobacter calcoaceticus strains had MDL 19,592 MIC50 of greater than or equal to 32 micrograms/ml. Although MDL 19,592 generally had a spectrum most similar to cefadroxil, it could not be represented by the cephalothin susceptibility test because of low predictive values and MIC correlations.

BMY-28100, a new oral cephalosporin: antimicrobial activity against nearly 7,000 recent clinical isolates, comparative potency with other oral agents, and activity against beta-lactamase producing isolates

The antimicrobial activity of BMY-28100 was tested against approximately 7,000 bacterial pathogens in a multicenter, multiphased collaborative investigation. The BMY-28100 spectrum and antimicrobial potency was most similar to that of cefaclor and superior to that of cephalexin among currently available cephalosporins. Species that had greater than or equal to 90% of clinical strains inhibited by BMY-28100 (less than or equal to 8.0 micrograms/ml) were: Citrobacter diversus, Escherichia coli, Klebsiella spp., Proteus mirabilis, Salmonella spp., Branhamella catarrhalis, Haemophilus influenzae, Neisseria gonorrhoeae, N. meningitidis, methicillin-susceptible Staphylococcus supp., Streptococcus pneumoniae, S. pyogenes, S. agalactiae, S. bovis, serogroup C and G streptococci, Listeria monocytogenes and gm-positive anaerobes. BMY-28100 inhibited 9% more of the 6286 fresh clinical isolates at less than or equal to 8.0 micrograms/ml than cefaclor at the same concentration. BMY-28100 was generally bactericidal, but MICs for some species were markedly increased when an inoculum concentration of 10(7) CFU/ml was used. Strains producing plasmid-mediated beta-lactamases (TEM, OXA, SHV, HMS) were susceptible to BMY-28100, cefaclor, and cefuroxime. BMY-28100 was less active against strains producing chromosomal-mediated beta-lactamases (Types I and IV). BMY-28100 was not hydrolyzed significantly by the tested plasmid-mediated beta-lactamases, but was destroyed by Type I cephalosporinases and Klebsiella K1 enzymes.

Antimicrobial activity of U-76,252 (CS-807), a new orally administered cephalosporin ester, including recommendations for MIC quality control

U-76,253A (R-3746), the active metabolite of the new cephalosporin ester, U-76,252 (CS-807), was tested against 4,742 fresh clinical isolates from four large medical centers. U-76,253A was very active against nearly all species of Enterobacteriaceae (87.7% inhibited at less than or equal to 4.0 micrograms/ml). Staphylococcus spp., and the streptococci. The U-76,253A spectrum was superior to the comparison orally administered cephalosporins (cephalexin, cephradine, cefaclor). Pseudomonas spp., Acinetobacter spp., and the enterococci were resistant to U-76,253A and the other tested drugs. Broth microdilution MIC quality control (QC) limits were established for U-76,253A in a multilaboratory investigation using a minimum of 125 MIC determinations per organism. The following MIC QC ranges were recommended; Escherichia coli (ATCC 25922) = 0.25-1.0 micrograms/ml, Staphylococcus aureus (ATCC 29213) = 2.0-4.0 micrograms/ml and Pseudomonas aeruginosa (ATCC 27853) = greater than 32 micrograms/ml.

In vitro evaluations of U-76,252 (CS-807): antimicrobial spectrum, beta-lactamase stability, and enzyme inhibition

Compound U-76,252 (Upjohn) is a cephalosporin ester that enhances oral absorption of the active free acid cephem, U-76,253. The active form structurally resembles parenteral aminothiazolyl-methoxyimino cephalosporins such as cefotaxime and its desacetyl metabolite. The g-negative antimicrobial activity of U-76,253 A (sodium salt of U-76,253) was most similar to that of cefixime and more potent than that of cefaclor or cefuroxime among the orally administered cephalosporins. Against g-positive bacteria, U-76,253 A was more active than cefixime. U-76,253 A was relatively stable to hydrolysis by five beta-lactamases (Type Ia, TEM-1, K1, CARB-2, and OXA-1), a stability most similar to cefotaxime and superior to that of cefaclor. Only the Type Ia (P99) enzyme was significantly inhibited by U-76,253 (IC 50 = 2.0 microM).