The antimicrobial lipopeptides polymyxin B and E (colistin) are being used as a 'last-line' therapy for infections caused by multidrug-resistant Gram-negative pathogens. Polymyxin resistance implies a total lack of antibiotics for the treatment of life-threatening infections caused by the Gram-negative 'superbugs'. This report details the structure-activity relationships (SAR) based design, in ...

THE properties of polymyxin in relation to ocular therapeutics have recently been discussed at some length ; the penetration of this antibiotic into the eye of the rabbit after subconjunctival injection was estimated and the results obtained in the treatment of corneal infection experimentally produced with Ps. pyocyanea have been reported (Ainslie and Smith, 1951). It is well known that this t...

A simple method for the rapid determination of antibiotic blood levels is described. Results are readily obtainable within 4 to 6 hr. The reported procedure is based upon determination of the highest dilution of a patient's serum capable of inhibiting dextrose fermentation by a standardized inoculum of a staphylococcus strain or of an Escherichia coli strain, when colymycin or polymyxin are inv...

Antimicrobial peptides exhibit high levels of antimicrobial activity against a broad range of spoilage and pathogenic microorganisms. Compared with bacteriocins produced by lactic acid bacteria, antimicrobial peptides from the genus Bacillus have been relatively less recognized despite their broad antimicrobial spectra. These peptides can be classified into two different groups based on whether...

OBJECTIVES The aim of the study was to develop a simple assay for rapid detection of the mcr-1 gene, recently identified as a source of plasmid-mediated acquired resistance to polymyxins in Enterobacteriaceae. METHODS A SYBR Green-based real-time PCR assay was designed for detection of the mcr-1 gene. This assay was applied to cultured bacteria and to spiked human and cattle stools. RESULTS...

Polymyxins are often considered as a last resort to treat multidrug resistant P. aeruginosa but polymyxin resistance has been increasingly reported worldwide in clinical isolates. Polymyxin resistance in P. aeruginosa is known to be associated with alterations in either PhoQ or PmrB. In this study, mutant strains of P. aeruginosa carrying amino acid substitution, a single and/or dual inactivati...