Variation in Indole-3-Acetic Acid Production by Wild Saccharomyces cerevisiae and S. paradoxus Strains from Diverse Ecological Sources and Its Effect on Growth

• Published in: PloS one Vol. 11; no. 8; p. e0160524
• Main Authors: Liu, Yen-Yu, Chen, Hung-Wei, Chou, Jui-Yu
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 02.08.2016; Public Library of Science (PLoS)
• Subjects: Acetic acid; Acid production; Baking yeast; Biology; Biology and Life Sciences; Biomaterials; Biosynthesis; Colorimetry; Culture Media - chemistry; Culture Media - pharmacology; Drosera; Ecological effects; Ecological monitoring; Ecology and Environmental Sciences; Education; Feedback, Physiological; Fungi; Gene expression; Genomes; Growth regulators; Indoleacetic acid; Indoleacetic Acids - metabolism; Indoleacetic Acids - pharmacology; Laboratories; Microorganisms; Physical Sciences; Physiological aspects; Physiology; Plant growth; Plant Growth Regulators - biosynthesis; Plant Growth Regulators - pharmacology; Plant hormones; Plants (botany); Research and Analysis Methods; Saccharomyces; Saccharomyces - drug effects; Saccharomyces - metabolism; Saccharomyces cerevisiae; Saccharomyces cerevisiae - drug effects; Saccharomyces cerevisiae - metabolism; Saccharomyces paradoxus; Species Specificity; Studies; Tryptophan; Tryptophan - metabolism; Tryptophan - pharmacology; Variance analysis; Yeast; Yeasts
• DOI: 10.1371/journal.pone.0160524
• ISSN: 1932-6203

Phytohormone indole-3-acetic acid (IAA) is the most common naturally occurring and most thoroughly studied plant growth regulator. Microbial synthesis of IAA has long been known. Microbial IAA biosynthesis has been proposed as possibly occurring through multiple pathways, as has been proven in plants. However, the biosynthetic pathways of IAA and the ecological roles of IAA in yeast have not been widely studied. In this study, we investigated the variation in IAA production and its effect on the growth of Saccharomyces cerevisiae and its closest relative Saccharomyces paradoxus yeasts from diverse ecological sources. We found that almost all Saccharomyces yeasts produced IAA when cultured in medium supplemented with the primary precursor of IAA, L-tryptophan (L-Trp). However, when cultured in medium without L-Trp, IAA production was only detected in three strains. Furthermore, exogenous added IAA exerted stimulatory and inhibitory effects on yeast growth. Interestingly, a negative correlation was observed between the amount of IAA production in the yeast cultures and the IAA inhibition ratio of their growth.