Open AccessSerum albumin promotes ATP ‐binding cassette transporter‐dependent sterol uptake in yeast
Author(s) -
Marek Magdalena,
Silvestro Daniele,
Fredslund Maria D.,
Andersen Tonni G.,
Pomorski Thomas G.
Publication year - 2014
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/1567-1364.12219
Subject(s) - sterol , biology , atp binding cassette transporter , biochemistry , transporter , saccharomyces cerevisiae , yeast , mutant , cholesterol , ergosterol , gene
Sterol uptake in fungi is a multistep process that involves interaction between external sterols and the cell wall, incorporation of sterol molecules into the plasma membrane, and subsequent integration into intracellular membranes for turnover. ATP ‐binding cassette ( ABC ) transporters have been implicated in sterol uptake, but key features of their activity remain to be elucidated. Here, we apply fluorescent cholesterol ( NBD ‐cholesterol) to monitor sterol uptake under anaerobic and aerobic conditions in two fungal species, Candida glabrata (Cg) and Saccharomyces cerevisiae (Sc). We found that in both fungal species, ABC transporter‐dependent uptake of cholesterol under anaerobic conditions and in mutants lacking HEM 1 gene is promoted in the presence of the serum protein albumin that is able to bind the sterol molecule. Furthermore, the C. glabrata ABC transporter CgAus1p expressed in S. cerevisiae requires the presence of serum or albumin for efficient cholesterol uptake. These results suggest that albumin can serve as sterol donor in ABC transporter‐dependent sterol uptake, a process potentially important for growth of C. glabrata inside infected humans.