Association for Biology Laboratory Education

Molecular ecology of wild yeasts: Isolating yeast species from the local environment
    

Sarah R. Stockwell

Advances in Biology Laboratory Education, 2024, Volume 44

https://doi.org/10.37590/able.v44.art19

Abstract

Wild yeasts are everywhere, an invisible and understudied part of our planet?s biodiversity. In this lab module, wild yeasts offer students an entry point into studying the ecology of their region. Over the course of 9 weeks (part time), students explore a natural area and choose their own samples of plants and insects, then culture their samples to isolate wild yeast strains. They DNA-barcode their strains and use the sequence data to identify what they have found. Finally, they look for patterns in pooled class data and present a research proposal for future experiments to identify associations between yeasts and their hosts. Students get a chance to collect genuinely novel data of interest to the scientific community while learning about their local environment. In addition, they practice important molecular biology and microbiology laboratory skills. They even have a chance of discovering a new species of yeast. Here, I provide materials to guide instructors through the some of the key experimental stages of the wild yeast project: collecting samples, inoculating liquid media, observing microbial growth in liquid culture, streaking strains to isolation, and studying colony morphology on agar plates.

Keywords:  microbiology, ecology, biodiversity, yeast, fungi, CURE, inquiry-based learning

University of California, San Diego (2023)