An alternative respiratory pathway on Candida krusei: implications on susceptibility profile and oxidative stress

• Type: Article in International Scientific Journal
• Date: 2012

Authors

costa-de-oliveira, s (Author) FMUP; sampaio-marques, b (Author) Other; barbosa, m (Author) Other; ricardo, e (Author) Other; pina-vaz, c (Author) FMUP; ludovico, p (Author) Other; rodrigues, ag (Author) FMUP

Journal

Title: FEMS Yeast Research

Vol. 12

Pages: 423-429

ISSN: 1567-1356

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 17 Citations

Scopus - 21 Citations

Scientific classification

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-002-96G

DOI: 10.1111/j.1567-1364.2012.00789.x

Abstract (EN): Our aim was to detect the presence of an alternative oxidase (AOX) in Candida krusei clinical strains and its influence on fluconazole susceptibility and in reactive oxygen species (ROS) production. Candida krusei clinical isolates were tested to evaluate the presence of AOX. Debaromyces hansenii 2968 (AOX positive) and Saccharomyces cerevisiae BY4742 (AOX negative) were used as control strains. Measurements of oxygen consumption were performed in the presence of 1 mM KCN, an inhibitor of the classical respiratory chain, and 5 mM salicylhydroxamic acid (SHAM). AOX expression was monitored by Western blotting using an AOX monoclonal antibody. Interactions between fluconazole and SHAM were performed using checkerboard assay. ROS production was evaluated in the presence of SHAM plus fluconazole, H2O2, menadione, or plumbagin. AOX was present in all C. krusei tested. The combination of fluconazole with SHAM resulted in an indifferent effect. In the presence of SHAM, the treatment with ROS inductors or fluconazole increased ROS production, except in the AOX-negative strain. An alternative respiratory pathway resistant to cyanide is described for the first time as a characteristic of C. krusei species. This AOX is unrelated to fluconazole resistance; however, it protects C. krusei from oxidative stress.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7