Physiological and Molecular Characterization of an Boron-Resistant Saccharomyces cerevisiae Strain Obtained by Evolutionary Engineering

One of the essential or beneficial micronutrient for plants and animals is boron that is an ultra-trace element. Although boron can inhibit the growth of Saccharomyces cerevisiae around 80 mM, it is also a growth supplement. However, little information is currently available regarding the molecular mechanisms and essentiality of boron. In this paper, the approach was to generate S. cerevisiae mutants with high boron resistance by using evolutionary engineering strategy that was previously applied successfully. Boron-resistant S. cerevisiae mutants were obtained and their phenotypic and physiological characteristics were determined. In order to identify the molecular mechanisms implicated in boron resistance, the whole transcriptomes and genome sequence analysis of wild type and one of the most resistant mutants were compared. BA8 resistant Saccharomyces cerevisiae (BA8) mutant strain and reference strain were grown in yeast minimal medium. When cultures’ Optical Density (OD600) reached to about 1, which correspond to the logarithmic growth phase of the yeast cells, total RNA isolation was carried out by using RNeasy Mini Kit (Qiagen). The experiment was performed triplicates. Whole-genome microarray analysis was carried out by using Agilent DNA Microarray Technology.