Biosynthesis of the Unique Wall Teichoic Acid of Staphylococcus aureus Lineage ST395

Abstract

The major clonal lineages of the human pathogen Staphylococcus aureus produce cell wall-anchored anionic poly-ribitol-phosphate (RboP) wall teichoic acids (WTA) substituted with d-Alanine and N-acetyl-d-glucosamine. The phylogenetically isolated S. aureus ST395 lineage has recently been found to produce a unique poly-glycerol-phosphate (GroP) WTA glycosylated with N-acetyl-d-galactosamine (GalNAc). ST395 clones bear putative WTA biosynthesis genes on a novel genetic element probably acquired from coagulase-negative staphylococci (CoNS). We elucidated the ST395 WTA biosynthesis pathway and identified three novel WTA biosynthetic genes, including those encoding an α-O-GalNAc transferase TagN, a nucleotide sugar epimerase TagV probably required for generation of the activated sugar donor substrate for TagN, and an unusually short GroP WTA polymerase TagF. By using a panel of mutants derived from ST395, the GalNAc residues carried by GroP WTA were found to be required for infection by the ST395-specific bacteriophage Φ187 and to play a crucial role in horizontal gene transfer of S. aureus pathogenicity islands (SaPIs). Notably, ectopic expression of ST395 WTA biosynthesis genes rendered normal S. aureus susceptible to Φ187 and enabled Φ187-mediated SaPI transfer from ST395 to regular S. aureus. We provide evidence that exchange of WTA genes and their combination in variable, mosaic-like gene clusters have shaped the evolution of staphylococci and their capacities to undergo horizontal gene transfer events.

Staphylococcus sciuri bacteriophages double-convert for staphylokinase and phospholipase, mediate interspecies plasmid transduction, and package mecA gene

“…3) supports the speculated interspecies horizontal transfer of mobile elements or their parts by phages. A reversible adsorption of both phages was observed in S. aureus PS 187 that has a distinct structure of WTA28, suggesting the possibility of a two-stage adsorption. This type of adsorption has been described for the B. subtilis SPP1 phage as a result of a missing YueB membrane receptor on mutant host cells, where the glucosylated poly (glycerol-phosphate) of cell WTA proved to be a major target for SPP1 reversible binding67.…”

Utilization of glycerophosphodiesters by Staphylococcus aureus

“…Extraction of wall teichoic acids from S. aureus cells and WTA-PAGE analysis was performed as previously described (Winstel et al, 2014).…”

Transfer of Plasmid DNA to Clinical Coagulase-Negative Staphylococcal Pathogens by Using a Unique Bacteriophage

“…Surprisingly, the S. aureus ST395 lineage-specific phage ⌽187 has been capable of transferring SaPIs between ST395 isolates and many CoNS because of shared properties in the WTA cell surface receptors (17). Genomic and biochemical analyses of the ST395 WTA biosynthesis pathway have further suggested the occurrence of previous HGT events between ST395 isolates and CoNS, most likely via ⌽187-related phages (20). Because most pathogenic CoNS, such as S. epidermidis, have a glycerol-phosphate WTA backbone resembling that of ST395 isolates, ⌽187 might be a suitable tool to transfer plasmid DNA to CoNS strains that are otherwise difficult to transform.…”