Identification of surface proteins in a clinical Staphylococcus haemolyticus isolate by bacterial surface shaving

Abstract

Background: The skin commensal Staphylococcus haemolyticus is an emerging nosocomial pathogen. Despite its clinical relevance, published information about S. haemolyticus virulence factors is scarce. In this study, the adhesive and biofilm forming properties of ten clinical and ten commensal S. haemolyticus strains were examined using standard adhesion and biofilm assays. One of the clinical strains was used to identify expressed surface proteins using bacterial surface shaving. Protein abundance was examined by a comparative analysis between bacterial protein expression after human keratinocyte (HaCaT) colonization and growth in cell culture media supplemented with serum. Relative protein quantification was performed by labeling peptides with tandem mass tags (TMT) prior to Mass Spectrometry analysis. Surface proteins can be used as novel targets for antimicrobial treatment and in diagnostics. Results: Adherence to fibronectin, collagen and plastic was low in all tested strains, but with significantly higher adhesion to fibronectin (p = 0.041) and collagen (p = 0.001) in the commensal strains. There was a trend towards higher degree of biofilm formation in the clinical strains (p = 0.059). By using surface shaving, 325 proteins were detected, of which 65 were classified as surface proteins. Analyses showed that the abundance of nineteen (5.8%) proteins were significantly changed following HaCaT colonization. The bacterial Toll/interleukin-1 like (TIRs) domain containing protein (p = 0.04), the transglycosylase SceD (p = 0.01), and the bifunctional autolysin Atl (p = 0.04) showed a 1.4, 1.6-and 1.5-fold increased abundance. The staphylococcal secretory antigen (SsaA) (p = 0.04) was significantly downregulated (− 1.5 fold change) following HaCaT colonization. Among the 65 surface proteins the elastin binding protein (Ebps), LPXAG and LPXSG domain containing proteins and five LPXTG domain containing proteins were identified; three Sdr-like proteins, the extracellular matrix binding protein Embp and a SasH-like protein.

Pathogenesis of Staphylococcus haemolyticus on primary human skin fibroblast cells

“…Surface shaving analysis identified 65 surface proteins, including 3 adhesins, extracellular matrix binding protein (Embp), Mannosylglucosyl-3-phosphoglycerate phosphatase (SasH-like) and others. Upon colonization, an increase in SceD and the autolysin Atl genes was observed [ 43 ]. In fact, no previous reports have clearly detected FnBP proteins inCoNS [ 44 ].…”

Clinical Infections, Antibiotic Resistance, and Pathogenesis of Staphylococcus haemolyticus

“…The adherence property of clinical S. haemolyticus is different from commensal S. haemolyticus. Commensal S. haemolyticus have high adherence to fibronectin and collagen, while clinical S. haemolyticus have low adherence to fibronectin and collagen [123]. However, using the bacteria surface shaving approach, 65 surface proteins were identified in clinical S. haemolyticus isolates and were associated with adherence to human keratinocytes such as the bacterial Toll/interleukin-1 like (TIRs) domain-containing protein, the bifunctional autolysin Atl, LPXTG, and the transglycosylase SceD [123].…”

Characterization of the Burkholderia cenocepacia J2315 Surface-Exposed Immunoproteome

“…The importance of using culture media mimicking the conditions of infection was highlighted by Liu et al, who found a total of 121 outer membrane proteins produced by B. cenocepacia strain Y10 after cultivation in different media, 37 proteins being uniquely identified when the cells were cultivated in ASM [48]. Wolden and colleagues also performed the cell-shaving technique with Staphylococcus haemolyticus after the bacterium's cultivation in the presence of keratinocytes, highlighting the importance of the use of the technique after host-microbe interaction [49].…”