Project description:Staphylococcus aureus and Staphylococcus epidermidis, two Gram-positive bacteria commonly found in the human skin microbiota, form biofilms that contribute to skin dysbiosis and play a key role in conditions like acne and atopic dermatitis. The Calcitonin Gene-Related Peptide (CGRP) is a human peptide involved in skin inflammation. We previously showed that CGRP enhances the virulence of S. epidermidis MFP04 and that the DnaK chaperone protein is significantly overexpressed in the secretome of CGRP-activated virulent S. epidermidis. In this study, we explored a potential new role of S. epidermidis DnaK in biofilm formation in both S. aureus and S. epidermidis. We showed that recombinant S. epidermidis DnaK differentially affects biofilm formation, whether in two skin commensal staphylococcal strains (S. aureus MFP03 and S. epidermidis MFP04) or in a clinical S. aureus strain (CIP 107093). In the clinical strain S. aureus CIP 107093, biofilm formation was most strongly inhibited. This inhibition involves both the Substrate-Binding Domain and the Nucleotide-Binding Domain of DnaK. Proteomic analysis revealed that DnaK alters the S. aureus biofilm proteome, stabilizing proteins involved in protein degradation like ClpP and ETA, while downregulating key regulatory proteins involved in biofilm development such as SaeS and WalK. These results indicate that S. epidermidis DnaK may contribute to the regulation of S. aureus biofilm formation, suggesting a cross-species regulatory role of DnaK within the skin microbiota.
2026-03-09 | PXD062742 | Pride
Project description:GACRC0009.Study on gut microecology of colorectal cancer
Project description:Skin commensal bacteria (Staphylococcus epidermidis) can help defend against skin infections, and they are increasingly being recognized for their role in benefiting skin health. This study aims to demonstrate the activities that Myristica fragrans Houtt. seed extracts, crude extract (CE) and essential oil (EO), have in terms of promoting the growth of the skin commensal bacterium S. epidermidis and providing metabolites under culture conditions to disrupt the biofilm formation of the common pathogen Staphylococcus aureus.
Project description:S. aureus and S. epidermidis were challenged with D-sphingosine, an antimicrobial lipid similar to sphingosines found in the major staphylococcal niche- human skin. Comparison of responses was used to identify resistance mechanisms and likely mode of action
Project description:Squalene makes up 12 % of human skin surface lipids, however little is known about its affects on the host skin microbiome. Here we tested the effect of squalene on genetic regulation of staphylococci, showing that it profoundly affects expression virulence or colonisation determinants, and of iron uptake systems.
Project description:Skin-resident Staphylococcus aureus, a common human commensal, can shape systemic immune responses without provoking inflammation in mice. This study demonstrates that topical skin colonization with live S. aureus robustly expands IL-17-producing Vγ6⁺ γδT17 cells both locally in the dermis and across distant tissues, including mucosal, lymphoid, and metabolic organs. This systemic reconfiguration is IL-1R-dependent yet independent of IL-23, TLR2, or the microbiota. Transcriptomic profiling reveals a transitional state in dermal Vγ6⁺ γδT cells, marked by changes in tissue-residency and migration-associated genes. Local proliferation, lymphatic trafficking and long-term recirculation sustain this response, even without systemic bacterial dissemination. These findings uncover a previously unrecognized allostatic process by which localized microbial signals recalibrate systemic immunological setpoints. The study expands our understanding of γδT17 cell dynamics and highlights their potential in tuning organismal fitness.
