Two Novel Semisynthetic Lipoglycopeptides Active against Biofilms and Cells in Late Stationary Growth Phase.

The increase in antibiotic resistance among Gram-positive bacteria underscores the urgent need to develop new antibiotics. New antibiotics should target actively growing susceptible bacteria that are resistant to clinically accepted antibiotics including bacteria that are not growing or are protected in a biofilm environment. In this paper, we compare the in vitro activities of two new semisynthetic glycopeptide antibiotics, MA79 and ERJ390, with two clinically used glycopeptide antibiotics-vancomycin and teicoplanin.

Role of membrane proteins in bacterial resistance to antimicrobial peptides.

Several natural antimicrobial peptides (AMPs), including the novel semisynthetic lipoglycopeptide antibiotics telavancin, dalbavancin, and oritavancin, have been approved for clinical use to address the growing problem of multiple antibiotic-resistant Gram-positive bacterial infections. Nevertheless, the efficacy of these antibiotics has already been compromised. The SARS-CoV-2 pandemic led to the increased clinical use of all antibiotics, further promoting the development of bacterial resistance.

Draft genome sequences of three clinical isolates of teicoplanin-resistant Staphylococcus epidermidis from patients without prior exposure to glycopeptide antibiotics.

Objectives: The aim of this study was to analyse the DNA sequences of three teicoplanin-resistant Staphylococcus epidermidis isolates collected from patients not previously treated with glycopeptide antibiotics.

Methods: The minimum inhibitory concentrations (MICs) of 12 antibiotics, including teicoplanin and vancomycin, were determined by the broth microdilution method. Genomic DNA was isolated, was sequenced by HiSeqX paired-end sequencing and was assembled into draft genome sequences using MyPro pipeline.

In Vivo Characterization of the Activation and Interaction of the VanR-VanS Two-Component Regulatory System Controlling Glycopeptide Antibiotic Resistance in Two Related Streptomyces Species.

The VanR-VanS two-component system is responsible for inducing resistance to glycopeptide antibiotics in various bacteria. We have performed a comparative study of the VanR-VanS systems from two streptomyces strains, Streptomyces coelicolor and Streptomyces toyocaensis, to characterize how the two proteins cooperate to signal the presence of antibiotics and to define the functional nature of each protein in each strain background. The results indicate that the glycopeptide antibiotic inducer specificity is determined solely by the differences between the amino acid sequences of the VanR-VanS two-component systems present in each strain rather than by any inherent differences in general cell properties, including cell wall structure and biosynthesis.