Proteomic and enzymatic response under Cr(VI) overload in yeast isolated from textile-dye industry effluent

IRAZUSTA VERÓNICA; ANAHI BERNAL; CRISTINA ESTEVEZ; LUCÍA INÉS FIGUEROA DE CASTELLANOS

ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2018

0147-6513

capacity for chromium detoxification via Cr(VI) biological reduction. The aim of the study was to evaluate theeffect of hexavalent chromium on synthesis of novel and/or specific proteins involved in chromium toleranceand reduction in response to chromium overload in two indigenous yeasts. A study was carried out following aproteomic approach with W. anomalus M10 and Cy. jadinii M9 strains. For this, proteins extracts belonging tototal cell extracts, membranes and mitochondria were analyzed. When Cr(VI) was added to culture mediumthere was an over-synthesis of 39 proteins involved in different metabolic pathways. In both strains, chromiumsupplementation changed protein biosynthesis by upregulating proteins involved in stress response, methioninemetabolism, energy production, protein degradation and novel oxide-reductase enzymes. Moreover, we observedthat Cy. jadinii M9 and W. anomalus M10 displayed ability to activate superoxide dismutase, catalase andchromate reductase activity. Two enzymes from the total cell extracts, type II nitroreductase (Frm2) and flavoproteinwrbA (Ycp4), were identified as possibly responsible for inducing crude chromate-reductase activity incytoplasm of W. anomalus M10 under chromium overload. In Cy.jadinii M9, mitochondrial Ferredoxine-NADPreductase (Yah1) and membrane FAD flavoprotein (Lpd1) were identified as probably involved in Cr(VI) reduction.To our knowledge, this is the first study proposing chromate reductase activity of these four enzymes inyeast and reporting a relationship between protein synthesis, enzymatic response and chromium biospeciation inCy. jadinii and W. anomalus.