Candid Photos

These colonies of Candida tropicalis cells may look innocent, but they turn out to have an unusually exciting sex life (for a yeast, at least). C. tropicalis causes infections of the skin and other parts of the body and was thought to only reproduce asexually, with each cell dividing in two to produce identical ‘daughters’. Researchers have now discovered that it can switch to one of two different ‘sexes’ for reproduction, highlighted in pink or yellow in this image. Intriguingly, the cells prefer same-sex mating, unlike many other yeasts. Even more strangely, they will only mate with the opposite sex as part of a mixed threesome, producing a lot of genetically diverse offspring. There’s a growing problem of drug-resistant C. tropicalis infections, particularly in people with AIDS or certain types of cancer, so finding out more about how they mix up their genes could help improve treatment in the future.

Written by Kat Arney

Kat Arney

Writer

Dr Kat Arney is an award-winning science writer, broadcaster and public speaker, and is the founder and Creative Director of First Create The Media.

Website

• Image from work by Han Du and Qiushi Zheng, and colleagues
• State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
• Originally published under a Creative Commons Licence (BY 4.0)
• Research published in PLOS Genetics, May 2018