Microbe-Microbe and Microbe-Host Interactions Relevant to the Skin Microbiome

PROJECT SUMMARY
The human skin microbiome plays a critical role in maintaining skin health, and dysbiosis of this system is
associated with increased incidence of disease. Probiotics purported to contain beneficial bacteria are
increasingly being used in skincare products, but the rationale for their application to the skin surface is lacking.
To develop effective probiotics, an improved understanding of the composition, function, and interactions of the
human skin microbiome is needed. The most common class of bacteria that comprises the healthy skin
microbiome is coagulase-negative staphylococci, but their role in maintaining skin health is not well understood.
Our preliminary data indicate that a common skin commensal, Staphylococcus hominis, produces a bacteriocin
that exhibits antimicrobial activity against other commensal skin bacteria. The first goal of this project is to
elucidate the structure and biosynthetic mechanisms of the bacteriocin. Additionally, we aim to investigate the
role of S. hominis bacteriocins and other S. hominis metabolites in mediating interactions between microbes and
eliciting host responses. Overall, this study aims to advance our understanding of the chemical and biological
interactions between the commensal bacteria and host cells, with the potential to inform the future development
of probiotics for maintaining skin health. The fellowship training plan, which will be carried out in a graduate
program that emphasizes research in natural products and integrative medicine, will augment the trainee’s skills
in mass spectrometry metabolomics, natural products isolation and structure elucidation, and will provide her an
opportunity to gain new skills in microbiology and microbiome research. The training plan has been tailored to
the specific planned career trajectory of the trainee, which is to become an independent researcher and secure
an academic position. The training will be conducted under the guidance of Dr. Nadja Cech (sponsor) and Dr.
Alexander Horswill (co-sponsor), both of whom have extensive experience mentoring students who have gone
on to tenured professorships. The project aligns with the mission of the National Center for Complementary and
Integrative Health (NCCIH), contributing to public health by providing insights that could inform the development
of skin probiotics.

Grant Number: 1F31AT012837-01A1
NIH Institute/Center: NIH
Principal Investigator: Zoie Bunch