Cletus P. Kurtzman

Cletus P. Kurtzman (July 19, 1938 – November 27, 2017) was an American mycologist who is known for his contributions to yeast taxonomy and is regarded as "the father of modern yeast taxonomy"(Boekhout, T 2019).

Career Kurtzman worked his entire scientific career (1967–2017) at the National Center for Agricultural Utilization Research, Northern Regional Research Center of United States Department of Agriculture in Peoria, Illinois. Among his many accomplishments, he helped pioneer techniques for defining ascomycete yeasts along multiple concepts using DNA-DNA recombination, phenotype and morphology before the advent of gene sequencing. Once gene sequencing became possible he would later determine that DNA recombination was time consuming and only useful for determining closely related species of yeasts. Kurtzman would redefine many clades within the Saccharomycotina group based on genetic similarity and helped formulate methods and tools that are currently used to help classify new species discovered within this group.

He held several leading positions including research leader and curator within the USDA, Some of his best known accomplishments involved expanding our knowledge of the Saccharomycotina and the Saccharomyces and Candida genera. Kurtzman's diversity work resulted in him describing 85 species, 21 genera, and five families. His lab became well known and trusted for its high quality analyses. "His later writings show an immense knowledge of the properties of various genes in terms of evolutionary rates, concordance with other genes, or the best primers or cycling conditions to obtain impeccable amplifications. The designation NRRL on a sequence deposit continues to be a certificate of quality" (Lachance, MA 2018).

Kurtzman was also fascinated with application of the many yeasts that he studied, including uses in biotechnology and clinical diagnostics. He is recognized for his discovery of the D-xylose and L-arabinose fermenting yeasts and their applications in the biofuels industry along with degradation of Fusarium mycotoxins by Blastobotrys spp, and the sorolipid-producing yeasts useful as surfactants.