Staphylococcus aureus small colony variants are resistant to the antimicrobial peptide lactoferricin B

Abstract

The resistance mechanism of SCVs towards the antimicrobial peptide lactoferricin B is presumably caused by the metabolic changes present in SCVs rather than by a changed transmembrane potential of SCVs or reduced uptake of the peptide.

Antimicrobial activity of Brazilian copaiba oils obtained from different species of the Copaifera genus

“…Copaiba oils obtained from C. martii, C. officinalis and C. reticulata (collected in Acre) showed in vitro bactericidal activity against a wide spectrum of Gram-positive organisms. This spectrum includes MRSA, for which there are very few therapeutic alternatives (Samuelsen et al 2005). Despite many recent advances in antimicrobial therapy, resistance among Gram-positive pathogens continues to pose a serious and growing clinical problem.…”

In Vivo Mutations of Thymidylate Synthase (Encoded by thyA ) Are Responsible for Thymidine Dependency in Clinical Small-Colony Variants of Staphylococcus aureus

“…The transcription patterns of important virulence regulators and metabolic and stress-related genes of TD-SCVs are dramatically changed, and these strains have a less virulent but more persistent phenotype (12) with decreased expression of ␣-hemolysin and increased expression of cell wall-associated proteins, such as protein A. Moreover, SCVs are more resistant to antibiotics and defensins (21,22,24) and survive intracellularly in various cell types, such as keratinocytes and epithelial and endothelial cells (11,32,33). The intracellular locus provides protection against antibiotic treatment and host defense.…”

Transgenic zebrafish eggs containing bactericidal peptide is a novel food supplement enhancing resistance to pathogenic infection of fish

“…However, these steps only add to the overall cost of producing artificial LFB. Meanwhile, there remains the additional possibility of generating a resistant strain against LFB [37] when artificial LFB is applied on a large scale, especially in aquatic ponds.…”