Respiratory chain network in mitochondria of Candida parapsilosis: ADP/O appraisal of the multiple electron pathways.
In this study we demonstrated that mitochondria of Candida parapsilosis contain a constitutive ubiquinol alternative oxidase (AOX) in addition to a classical respiratory chain (CRC) and a parallel respiratory chain (PAR) both terminating by two different cytochrome c oxidases. The C. parapsilosis AOX is characterized by a fungi-type regulation by GMP (as a stimulator) and linoleic acid (as an inhibitor). Inhibitor screening of the respiratory network by the ADP/O ratio and state 3 respiration determinations showed that (i) oxygen can be reduced by the three terminal oxidases through four paths implying one bypass between CRC and PAR and (ii) the sum of CRC, AOX and PAR capacities is higher than the overall respiration (no additivity) and that their engagement could be progressive according to the redox state of ubiquinone, i.e. first cytochrome pathway, then AOX and finally PAR.
Milani
G
G
Departamento de Patologia Clínica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, SP, Brazil.
Jarmuszkiewicz
W
W
Sluse-Goffart
C M
CM
Schreiber
A Z
AZ
Vercesi
A E
AE
Sluse
F E
FE
D000244:Adenosine Diphosphate / Q000378:metabolism*; D002175:Candida / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D019069:Cell Respiration / Q000187:drug effects; D003485:Cyanates / Q000494:pharmacology; D004579:Electron Transport / Q000187:drug effects; D006157:Guanosine Monophosphate / Q000494:pharmacology; D006877:Hydroxamic Acids / Q000494:pharmacology; D019787:Linoleic Acid / Q000494:pharmacology; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D024101:Mitochondrial Proteins; D009243:NAD / Q000378:metabolism; D010088:Oxidoreductases / Q000037:antagonists & inhibitors / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism*; D010940:Plant Proteins; D000099188:Alternative Oxidase
D000244:Adenosine Diphosphate; D003485:Cyanates; D006157:Guanosine Monophosphate; D006877:Hydroxamic Acids; D019787:Linoleic Acid; D024101:Mitochondrial Proteins; D009243:NAD; D010088:Oxidoreductases; D010100:Oxygen; D010940:Plant Proteins; D000099188:Alternative Oxidase; C024835:potassium cyanate; C006696:benzohydroxamic acid