title: Oxidative stress and antioxidant response in a thermotolerant yeast.
abstract: Stress tolerance is a key attribute that must be considered when using yeast cells for industrial applications. High temperature is one factor that can cause stress in yeast. High environmental temperature in particular may exert a natural selection pressure to evolve yeasts into thermotolerant strains. In the present study, three yeasts (Saccharomyces cerevisiae, MC4, and Kluyveromyces marxianus, OFF1 and SLP1) isolated from hot environments were exposed to increased temperatures and were then compared with a laboratory yeast strain. Their resistance to high temperature, oxidative stress, and antioxidant response were evaluated, along with the fatty acid composition of their cell membranes. The SLP1 strain showed a higher specific growth rate, biomass yield, and biomass volumetric productivity while also showing lower duplication time, reactive oxygen species (ROS) production, and lipid peroxidation. In addition, the SLP1 strain demonstrated more catalase activity after temperature was increased, and this strain also showed membranes enriched in saturated fatty acids. It is concluded that the SLP1 yeast strain is a thermotolerant yeast with less oxidative stress and a greater antioxidant response. Therefore, this strain could be used for fermentation at high temperatures.
authors.affiliation: Universidad Michoacana de San Nicolás de Hidalgo, Instituto de Investigaciones Químico-Biológicas, Morelia, Mich., Mexico.
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Mejía-Barajas
authors.affiliation: Universidad Michoacana de San Nicolás de Hidalgo, Instituto de Investigaciones Químico-Biológicas, Morelia, Mich., Mexico.
authors.forename: Rocío
authors.initials: R
authors.lastname: Montoya-Pérez
authors.affiliation: Universidad Michoacana de San Nicolás de Hidalgo, Instituto de Investigaciones Químico-Biológicas, Morelia, Mich., Mexico.
authors.forename: Rafael
authors.initials: R
authors.lastname: Salgado-Garciglia
authors.affiliation: University of Texas Medical Branch at Galveston, Galveston, USA.
authors.forename: Leopoldo
authors.initials: L
authors.lastname: Aguilera-Aguirre
authors.affiliation: Universidad Michoacana de San Nicolás de Hidalgo, Instituto de Investigaciones Químico-Biológicas, Morelia, Mich., Mexico.
authors.forename: Christian
authors.initials: C
authors.lastname: Cortés-Rojo
authors.affiliation: Universidade Nacional Autónoma de Mexico, FES Iztacala, Unidad de Biomedicina Tlalnepantla, Mexico.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Mejía-Zepeda
authors.affiliation: Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, Guadalajara, Mexico.
authors.forename: Melchor
authors.initials: M
authors.lastname: Arellano-Plaza
authors.affiliation: Universidad Michoacana de San Nicolás de Hidalgo, Instituto de Investigaciones Químico-Biológicas, Morelia, Mich., Mexico. Electronic address: saavedra@umich.mx.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Saavedra-Molina
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D018533:Biomass; D002374:Catalase / Q000032:analysis; D002462:Cell Membrane / Q000737:chemistry; D005227:Fatty Acids / Q000032:analysis; D006358:Hot Temperature; D007716:Kluyveromyces / Q000737:chemistry / Q000254:growth & development / Q000502:physiology* / Q000528:radiation effects; D015227:Lipid Peroxidation; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000254:growth & development / Q000502:physiology* / Q000528:radiation effects; D013312:Stress, Physiological
chemical_list: D000975:Antioxidants; D005227:Fatty Acids; D017382:Reactive Oxygen Species; D002374:Catalase
keywords: Increased temperature; Oxygen-derived free radicals; Thermotolerant; Yeast