Yeast, a single celled fungi, is a microorganism that is a critical part of wine production. While the yeast used for winemaking can be wild strains, there is currently no known substitute for yeast in the fermentation process.
https://en.wikipedia.org/wiki/Yeast_in_winemaking
Yeast is also an essential component in brewing. Currently there is no known substitute for yeast in the brewing process. In addition, different yeast strains result in different flavor profiles and nuances. If variety is the spice of life, we have the genetic diversity of yeast to thank for that.
https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae
Yeast is also an important component in baking. For baking, there are yeast substitutes available, however some substitutes, like sourdough starter, also utilize yeast as the primary active component. Utilizing the other non-yeast substitutes for leavening agents results in texture and flavor that is never quite the same as using real yeast.
Many varieties of yeast have already been genetically sequenced, and scientists are continually working on unlocking more of yeast’s mysteries.
https://www.frontiersin.org/articles/10.3389/fmicb.2018.00965/full