Odor-causing bacteria in armpits targeted using bacteriophage-derived lysin

Bacteriophage therapy could be developed based on study’s results

A source of body odor: Native bacteria metabolize sweat in the armpits, causing odor to arise.

Body odor from the armpits comes from bacteria metabolizing sweat produced by the apocrine glands. These bacteria are native to our skin, but the odors produced differ among people. Generally, people use deodorants on their armpits, but perhaps there is a way to get rid of the bacteria.

To find out, a research team led by Osaka Metropolitan University Professor Satoshi Uematsu and Associate Professor Kosuke Fujimoto at the Graduate School of Medicine collected body fluid samples from the armpits of 20 men that were deemed healthy. In advance, a subjective olfactory panel classified them into two types of odors, with 11 having a more noticeable smell. The researchers analyzed the matter produced from bacterial metabolism and the DNA of the skin microflora and found an increased presence of odor-causing precursors in those 11 samples along with a proliferation of Staphylococcus hominis bacteria.

The team then synthesized a lysin from a bacteriophage, or virus that attacks bacteria, that infects S. hominis. During in vitro experiments, this lysin was found to target only S. hominis, not other bacteria normally present on the skin.

“We performed a large-scale metagenomic analysis of the skin microflora using the SHIROKANE supercomputer at the University of Tokyo and found that S. hominis is important in the development of odor,” said Assistant Professor Miho Uematsu in the Department of Immunology and Genomics. “The identification of the lysin that attacks S. hominis is also the result of the comprehensive genome analysis.”

Dr. Miki Watanabe, who is part of the Department of Immunology and Genomics and the Department of Dermatology added: “Axillary [armpit] odors are one of the few dermatological disorders in which bacteria are the primary cause. Although many patients suffer from axillary odors, there are few treatment options. We believe that this study will lead to a new therapy.”

The study was published in the Journal of Investigative Dermatology.

Conflict of Interest Statement

Authors declare that they have no competing interests.


About OMU

Established in Osaka as one of the largest public universities in Japan, Osaka Metropolitan University is committed to shaping the future of society through “Convergence of Knowledge” and the promotion of world-class research. For more research news, visit https://www.omu.ac.jp/en/ and follow us on social media: X, Facebook, Instagram, LinkedIn.

Published: 23 Apr 2024

Contact details:

Rina Matsuki

3-3-138 Sugimoto, Sumiyoshi-ku,
Osaka 558-8585 JAPAN

News topics: 
Academic disciplines: 
Content type: 

Journal of Investigative Dermatology
Title: Targeted lysis of Staphylococcus hominis linked to axillary osmidrosis using bacteriophage-derived endolysin
DOI: 10.1016/j.jid.2024.03.039
Author(s): Miki Watanabe, Miho Uematsu, Kosuke Fujimoto, Takeshi Hara, Mako Yamamoto, Daichi Miyaoka, Chieko Yokota, Yukari Kamei, Akira Sugimoto, Natsuko Kawasaki, Takato Yabuno, Noriaki Sato, Shintaro Sato, Kiyoshi Yamaguchi, Yoichi Furukawa, Daisuke Tsuruta, Fumihiro Okada, Seiya Imoto, Satoshi Uematsu
Publication date: 19 April 2024
URL: https://doi.org/10.1016/j.jid.2024.03.039

Funding information:

This study was supported by the Japanese Society for the Promotion of Science (22H00477, 21H03538, 22K16329, 22K15733), the Japan Agency for Medical Research and Development (AMED) (JP23fk0108619, JP23ae0121040, JP23ae0121048), and the Grant for Innovation Creation from Osaka City (2021). This study was conducted in collaboration with Mandom Corp.