Influence of the metabolic state on the tolerance of Pichia kudriavzevii to heavy metals.
This work aims to examine the influence of the metabolic state of the yeast Pichia kudriavzevii on the susceptibility to a metals mixture (5 mg L-1Cd, 10 mg L-1Pb, and 5 mg L-1Zn). Cells exposed to the metals mixture in the presence of 25 mmol L-1glucose displayed a higher loss of membrane integrity and proliferation capacity, compared to cells incubated in the absence of glucose. The analysis of the effect of individual metals revealed that glucose increased the toxic effect of Cd marginally, and of Pb significantly. The increased susceptibility to heavy metals due to glucose was attenuated in the simultaneous presence of a mitochondrial respiration inhibitor such as sodium azide (NaN3). ATP-depleted yeast cells, resulting from treatment with the non-metabolizable glucose analogue 2-deoxy-d-glucose, showed an increased susceptibility to heavy metals mixture. Pre-incubation of yeast cells with 1 or 1.5 mmol L-1Ca2+reduced significantly (P < 0.05) the loss of membrane integrity induced by the metals mixture. These findings contribute to the understanding of metals mechanisms of toxicity in the non-conventional yeast P. kudriavzevii.
Bioengineering Laboratory-CIETI, Department of Chemical Engineering, ISEP-School of Engineering of Polytechnic Institute of Porto, Porto, 4200-072, Portugal.|Department of Biology, Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil.
Vanessa A
VA
Mesquita
Bioengineering Laboratory-CIETI, Department of Chemical Engineering, ISEP-School of Engineering of Polytechnic Institute of Porto, Porto, 4200-072, Portugal.|CEB-Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga, 4710-057, Portugal.
Manuela D
MD
Machado
Department of Biology, Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil.
Cristina F
CF
Silva
Bioengineering Laboratory-CIETI, Department of Chemical Engineering, ISEP-School of Engineering of Polytechnic Institute of Porto, Porto, 4200-072, Portugal.|CEB-Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga, 4710-057, Portugal.
Eduardo V
EV
Soares
D002104:Cadmium / Q000633:toxicity; D003847:Deoxyglucose / Q000494:pharmacology; D004785:Environmental Pollutants / Q000633:toxicity; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology; D019216:Metals, Heavy / Q000633:toxicity*; D010843:Pichia / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism*; D019810:Sodium Azide / Q000633:toxicity; D015032:Zinc / Q000633:toxicity
D004785:Environmental Pollutants; D019216:Metals, Heavy; D002104:Cadmium; D019810:Sodium Azide; D003847:Deoxyglucose; D005947:Glucose; D015032:Zinc
2-deoxy-d-glucose (2-DOG); Heavy metals toxicity; Membrane integrity; Sodium azide; Yeast viability