Isolation and Characterization of Barosensitive Mutants of Saccharomyces cerevisiae Obtained by UV Mutagenesis

• Published in: Journal of food science Vol. 75; no. 8; pp. M509 - M514
• Main Authors: Shigematsu, Toru, Nasuhara, Yusuke, Nagai, Gen, Nomura, Kazuki, Ikarashi, Kenta, Hirayama, Masao, Hayashi, Mayumi, Ueno, Shigeaki, Fujii, Tomoyuki
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01.10.2010; Wiley; Wiley Subscription Services, Inc
• Subjects: alcoholic fermentation; barosensitive mutants; barosensitivity; Biological and medical sciences; Ethanol - metabolism; Fermentation; Food industries; Food Microbiology; Food safety; Food science; Fundamental and applied biological sciences. Psychology; Fungi; high pressure treatment; high-pressure processing; inactivation; inactivation kinetics; Kinetics; microbial growth; Microbial Viability; Mutagenesis; mutants; Mutation; Pressure; Reaction kinetics; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - isolation & purification; Saccharomyces cerevisiae - metabolism; strain differences; ultraviolet radiation; Ultraviolet Rays; UV mutagenesis; viability; yeasts; Ascomycota; Yeast; Physical dressing; high-pressure processing; Inactivation; UV mutagenesis; High pressure; Fungi; Characterization; Mutagenesis; Isolation; Kinetics; Mutation; Saccharomyces cerevisiae; inactivation kinetics; barosensitive mutants
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/j.1750-3841.2010.01789.x

Using UV mutagenesis, 2 high-pressure (HP) sensitive (barosensitive) mutants of Saccharomyces cerevisiae were obtained. The HP inactivation of the mutants, as well as their parent strains, followed 1st-order kinetics in the range of 175 to 250 MPa within 600 s. Both mutants showed larger 1st-order inactivation rate constant values or significant loss of viabilities, compared with their parent strains in the pressure range tested. The inactivation rate constant value of one of the mutants was comparable with that of a previously reported highly barosensitive strain, which was generated by deletion of hsp104 in a trehalose deficient strain. The activation volume values of HP inactivation reactions in the 2 mutants were apparently equivalent with those of their parent strains. This suggested that the mutation did not bring drastic volume changes of the key molecules for HP inactivation. Their auxotrophic properties, growth, and ethanol fermentation were identical in mutant and parent strains. The mutants could therefore be useful for fermentations where control by HP processing is desired.