Effect of sodium nitroprusside on H+-ATPase activity and ATP concentration in Candida albicans.
ATP hydrolysis by plasma membrane H+-ATPase from Candida albicans has been investigated in presence of nitric oxide and various nutrients (sugars and amino acids). Sodium nitroprusside (SNP) was used as nitric oxide donor. It was found that ATP concentration decreased in SNP treated cells which was more in presence of sugars like glucose, xylose and 2-deoxy-D-glucose and amino acids as compared to their respective controls. The activity of H+-ATPase from plasma membrane decreased by 70 % in SNP treated cells. Both in vivo and in vitro treatments of SNP showed almost similar effects of decrease in ATPase activity. Effect of SNP was more pronounced in presence of nutrients. Interestingly, it was observed that vanadate did not show any independent effect in presence of nitric oxide. Several workers have reported similar type of results with other P-type ATPases. For the first time, it was observed in the present study that in presence of nitric oxide, H+-ATPase activity decreased like other P-type ATPases. Our study indicated that NO had a significant effect on ATP synthesis and activity of H+- ATPase. In the presence of NO, the ATP concentration was decreased indicating it affected mitochondrial electron transport chain. It may be concluded that NO, not only affects (inhibit) mitochondrial electron transport chain but also interferes with H+- ATPase of plasma membrane by changing its conformation resulting in decreased activity.
Haque
Mohammad Mahfuzul
MM
Enzyme Kinetics and Molecular Physiology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India.
Pooja
Manzoor
Nikhat
N
Khan
Luqman A
LA
Basir
Seemi Farhat
SF
D000251:Adenosine Triphosphatases / Q000378:metabolism / Q000502:physiology*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D002176:Candida albicans / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D004579:Electron Transport; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008928:Mitochondria / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology; D020030:Nitric Oxide Donors / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology*; D020641:Polymorphism, Single Nucleotide
D020030:Nitric Oxide Donors; D009599:Nitroprusside; D009569:Nitric Oxide; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases