Quorum sensing activity and control of yeast-mycelium dimorphism in Ophiostoma floccosum

Authors

Alexander Berrocal, Instituto Tecnológico de Costa RicaFollow
Claudia Oviedo, Universidad del Bío Bío
Kenneth W. Nickerson, University of Nebraska-LincolnFollow
José Navarrete, Universidad del Bío Bío

Date of this Version

2014

Citation

Published in Biotechnology Letters 36 (2014), pp 1503–1513. doi 10.1007/s10529-014-1514-5

Comments

Copyright © 2014 Springer Science+Business Media Dordrecht. Used by permission.

Abstract

Quorum sensing (QS) activity in Ophiostoma fungi has not been described. We have examined the growth conditions on the control of dimorphism in Ophiostoma floccosum, an attractive biocontrol agent against blue-stain fungi, and its relationship with QS activity. In a defined culture medium with l-proline as the N source, a high inoculum size (10⁷ c.f.u. ml^-1) was the principal factor that promoted yeast-like growth. Inoculum size effect can be explained by the secretion of a QS molecule(s) (QSMs) responsible for inducing yeast morphology. QSM candidates were extracted from spent medium and their structure was determined by GC–MS. Three cyclic sesquiterpenes were found. The most abundant molecule, and therefore the principal candidate to be the QSM responsible for yeast growth of O. floccosum, was 1,1,4a-trimethyl-5,6-dimethylene-decalin (C₁₅H₂₄). Other two compounds were also detected.