Occurrence and biochemical characterization of GTP-binding proteins in Candida albicans.
The activities of GTP-binding and GTPase in Candida albicans were present in the cytosol, KCl- and cholate-extractable fractions. At least two kinds of GTP-binding proteins were found in the cytosolic fraction; the major one with a molecular mass of about 30 kDa and the other about 500 kDa. The former specifically bound guanine nucleotides and was most likely to bind GDP since guanosine 5'-O-(thio) triphosphate (GTP gamma S)-binding was accelerated by addition of (NH4)2SO4. The latter showed no specificity in nucleotide binding and could also bind adenine nucleotides. The proteins were not ADP-ribosylated by either pertussis toxin or cholera toxin. These results indicate that ras-like monomeric, low molecular mass GTP-binding proteins distinct from heterotrimeric G proteins such as Gi, Go and Gs are present in C. albicans.
Nagata
K
K
Department of Biochemistry, Gifu University School of Medicine, Japan.
Suzuki
T
T
Morita
T
T
Okano
Y
Y
Nozawa
Y
Y
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D001667:Binding, Competitive; D002176:Candida albicans / Q000737:chemistry* / Q000201:enzymology / Q000378:metabolism; D002850:Chromatography, Gel; D003600:Cytosol / Q000737:chemistry; D020558:GTP Phosphohydrolases / Q000032:analysis; D019204:GTP-Binding Proteins / Q000032:analysis* / Q000378:metabolism; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000378:metabolism; D006153:Guanosine Diphosphate / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D008274:Magnesium / Q000494:pharmacology
D006153:Guanosine Diphosphate; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D000244:Adenosine Diphosphate; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins; D008274:Magnesium