Features Partner Sites Information LinkXpress
Sign In
Demo Company

Strain Differences Separate Helpful and Harmful Elements of the Human Microbiome

By BiotechDaily International staff writers
Posted on 12 Mar 2013
Print article
A recent microbiome study demonstrated the importance of evaluating bacteria at the strain rather than the genus or species level in order to understand their contribution to human health or disease.

Investigators at the University of California, Los Angeles (USA) and collaborators at Washington University (St. Louis, MO, USA) and the Los Angeles Biomedical Research Institute (CA, USA) selected the skin disorder acne as a model to explore the relationship between the causative organism Propionibacterium acnes and the human immune system, which generates the inflammatory response that causes the characteristic pimples, redness, and blotchy skin.

The investigators compared the skin microbiome at the strain level and genome level of P. acnes between 49 acne patients and 52 healthy individuals by sampling the sebaceous units on their noses. More than 1,000 strains of the bacteria were cultured from the isolates, and the genomes of 66 of the P. acnes strains were sequenced.

Metagenomic analysis published in the February 28, 2013, online edition of the Journal of Investigative Dermatology demonstrated that although the relative abundances of P. acnes were similar, the strain population structures were significantly different in the two cohorts. Certain strains were highly associated with acne, and other strains were enriched in healthy skin.

By sequencing 66 previously unreported P. acnes strains and comparing 71 P. acnes genomes, the investigators identified potential genetic determinants of various P. acnes strains in association with acne or health. The analysis suggested that acquired DNA sequences and bacterial immune elements may have roles in determining virulence properties of P. acnes strains, and some could be future targets for therapeutic interventions. Furthermore, the results underscored the importance of strain-level analysis of the human microbiome to define the role of the microbial flora in health and disease.

"We learned that not all acne bacteria trigger pimples—one strain may actually help keep skin healthy," said senior author Dr. Huiying Li, assistant professor of molecular and medical pharmacology at the University of California, Los Angeles. "We hope to apply our findings to develop new strategies that stop blemishes before they start, and enable dermatologists to customize treatment to each patient's unique cocktail of skin bacteria."

"We were extremely excited to uncover a third strain of P. acnes that is common in healthy skin yet rarely found when acne is present," said Dr. Li. "We suspect that this strain contains a natural defense mechanism that enables it to recognize attackers and destroy them before they infect the bacterial cell. This P. acnes strain may protect the skin, much like yogurt's live bacteria help defend the gut from harmful bugs. Our next step will be to investigate whether a probiotic cream can block bad bacteria from invading the skin and prevent pimples before they start."

Related Links:
University of California, Los Angeles
Washington University
Los Angeles Biomedical Research Institute

Print article



view channel

Molecular Light Shed on “Dark” Cellular Receptors

Scientists have created a new research tool to help find homes for orphan cell-surface receptors, toward better understanding of cell signaling, developing new therapeutics, and determining causes of drug side-effects. The approach may be broadly useful for discovering interactions of orphan receptors with endogenous, naturally... Read more

Lab Technologies

view channel
Image: The new ambr 15 fermentation micro-bioreactor system was designed to enhance microbial strain screening applications (Photo courtesy of Sartorius Stedim Biotech).

New Bioreactor System Streamlines Strain Screening and Culture

Biotechnology laboratories working with bacterial cultures will benefit from a new automated micro bioreactor system that was designed to enhance microbial strain screening processes. The Sartorius... Read more


view channel

Purchase of Biopharmaceutical Company Will Boost Development of Nitroxyl-Based Cardiovascular Disease Drugs

A major international biopharmaceutical company has announced the acquisition of a private biotech company that specializes in the development of drugs for treatment of cardiovascular disease. Bristol-Myers Squibb Co. (New York, NY, USA) has initiated the process to buy Cardioxyl Pharmaceuticals Inc. (Chapel Hill, NC, USA).... Read more
Copyright © 2000-2015 Globetech Media. All rights reserved.