ABSTRACT
The composition of the skin microbiota varies widely among individuals when sampled at the same body site. A key question is which molecular factors determine strain-level variability within sub-ecosystems of the skin microbiota. Here, we used a genomics-guided approach to identify an antibacterial biosynthetic gene cluster in Cutibacterium acnes (formerly Propionibacterium acnes), a human skin commensal bacterium that is widely distributed across individuals and skin sites. Experimental characterization of this biosynthetic gene cluster resulted in identification of a new thiopeptide antibiotic, cutimycin. Analysis of individual human skin hair follicles revealed that cutimycin contributed to the ecology of the skin hair follicle microbiota and helped to reduce colonization of skin hair follicles by Staphylococcus species.
Subject(s)
Hair Follicle , Microbiota , Anti-Bacterial Agents/pharmacology , Humans , Propionibacterium acnes , SkinABSTRACT
This review provides an overview of current knowledge concerning type IVb pili in Gram-negative bacteria. The number of these pili identified is steadily increasing with genome sequencing and mining studies, but studies of these pili are somewhat uneven, because their expression is tightly regulated and the signals or regulators controlling expression need to be identified. However, as illustrated here, they have a number of interesting functional, assembly-related and regulatory features.
Subject(s)
Fimbriae, Bacterial/physiology , Gram-Negative Bacteria/physiology , Fimbriae Proteins/genetics , Fimbriae Proteins/metabolism , Fimbriae, Bacterial/chemistry , Fimbriae, Bacterial/genetics , Gene Expression Regulation, Bacterial , Gram-Negative Bacteria/chemistry , Gram-Negative Bacteria/genetics , Models, Biological , Models, Molecular , Multiprotein Complexes/genetics , Multiprotein Complexes/metabolism , Protein Multimerization , Signal TransductionABSTRACT
A method for replacing endogenous promoter by a constitutive promoter in Pseudomonas aeruginosa is described. Plasmid pKNG101, a broadly used shuttle suicide vector in P. aeruginosa, was improved to allow chromosomal introduction of a Plac promoter in front of any kind of gene especially those with unknown function. Using this strategy alleviates the need for cloning difficulties encountered in this bacteria and antibiotic marker selection.
