title: Variations in oxygen concentration cause differential antioxidant response and expression of related genes in Beauveria bassiana.
abstract: The entomopathogenic fungus Beauveria bassiana is widely used in pest biocontrol strategies. We evaluated both the antioxidant response mediated by compatible solutes, trehalose or mannitol, and the expression of related genes using oxygen pulses at three oxygen concentrations in solid state culture (SSC): normal atmosphere (21% O2), low oxygen (16% O2) and enriched oxygen (26% O2). Trehalose concentration decreased 75% after atmospheric modifications in the cultures, whereas mannitol synthesis was three-fold higher under the 16% O2 pulses relative to normal atmosphere (100 and 30 μg mannitol mg(-1) biomass, respectively). Confirming this result, expression of the mpd gene, coding for mannitol-1-P dehydrogenase (MPD), increased up to 1.4 times after O2 pulses. The expression of the bbrgs1 gene, encoding a regulatory G protein related to conidiation, was analysed to explain previously reported differences in conidial production. Surprisingly, expression of bbrgs1 decreased after atmospheric modification. Finally, principal component analysis (PCA) indicated that 83.39% of the variability in the data could be explained by two components. This analysis corroborated the positive correlation between mannitol concentration and mpd gene expression, as well as the negative correlation between conidial production and bbrgs1 gene expression. This study contributes to understanding of antioxidant and molecular response of B. bassiana induced under oxidant conditions.
authors: Universidad Autónoma Metropolitana Iztapalapa, Departamento de Biotecnología, San Rafael Atlixco 186, Col. Vicentina, C. P. 09340, México D. F., Mexico.
authors: Paul Misael
authors: PM
authors: Garza-López
authors: Universidad Autónoma Metropolitana Iztapalapa, Departamento de Biotecnología, San Rafael Atlixco 186, Col. Vicentina, C. P. 09340, México D. F., Mexico.
authors: Gerardo
authors: G
authors: Suárez-Vergel
authors: Universidad Autónoma Metropolitana Xochimilco, Departamento de Sistemas Biológicos, Calz. del Hueso 1100, Col. Villa Quietud, C. P. 04960, México, D. F., Mexico.
authors: Aida
authors: A
authors: Hamdan-Partida
authors: Universidad Autónoma Metropolitana Iztapalapa, Departamento de Biotecnología, San Rafael Atlixco 186, Col. Vicentina, C. P. 09340, México D. F., Mexico. Electronic address: loera@xanum.uam.mx.
authors: Octavio
authors: O
authors: Loera
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D052982:Beauveria / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D020869:Gene Expression Profiling; D008353:Mannitol / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism*; D020710:RGS Proteins / Q000096:biosynthesis / Q000235:genetics; D013172:Spores, Fungal / Q000254:growth & development; D013312:Stress, Physiological; D013401:Sugar Alcohol Dehydrogenases / Q000096:biosynthesis / Q000235:genetics; D014199:Trehalose / Q000378:metabolism
chemical_list: D000975:Antioxidants; D003470:Culture Media; D020710:RGS Proteins; D008353:Mannitol; D014199:Trehalose; D013401:Sugar Alcohol Dehydrogenases; C021544:mannitol-1-phosphate dehydrogenase; D010100:Oxygen
keywords: Compatible solutes; Differential gene expression; Entomopathogenic fungus; Oxidant conditions; Principal component analysis