D-Erythroascorbic acid activates cyanide-resistant respiration in Candida albicans.
Higher plants, protists and fungi possess cyanide-resistant respiratory pathway, which is mediated by alternative oxidase (AOX). The activity of AOX has been found to be dependent on several regulatory mechanisms including gene expression and posttranslational regulation. In the present study, we report that the presence of cyanide in culture medium remarkably retarded the growth of alo1/alo1 mutant of Candida albicans, which lacks d-arabinono-1,4-lactone oxidase (ALO) that catalyzes the final step of d-erythroascorbic acid (EASC) biosynthesis. Measurement of respiratory activity and Western blot analysis revealed that increase in the intracellular EASC level induces the expression of AOX in C. albicans. AOX could still be induced by antimycin A, a respiratory inhibitor, in the absence of EASC, suggesting that several factors may act in parallel pathways to induce the expression of AOX. Taken together, our results suggest that EASC plays important roles in activation of cyanide-resistant respiration in C. albicans.
Huh
Won-Ki
WK
School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-747, Republic of Korea.
Song
Yong Bhum
YB
Lee
Young-Seok
YS
Ha
Cheol Woong
CW
Kim
Seong-Tae
ST
Kang
Sa-Ouk
SO
D001205:Ascorbic Acid / Q000008:administration & dosage*; D002176:Candida albicans / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D003486:Cyanides / Q000008:administration & dosage*; D025141:Drug Resistance, Fungal / Q000187:drug effects / Q000502:physiology*; D024101:Mitochondrial Proteins; D010088:Oxidoreductases / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010940:Plant Proteins; D000099188:Alternative Oxidase
D001205:Ascorbic Acid; D003486:Cyanides; D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010100:Oxygen; D010940:Plant Proteins; D000099188:Alternative Oxidase; C005056:isoascorbic acid