Detection of β‐1,2‐mannosyltransferase in Candida albicans cells

[摘要]

A particulate insoluble fraction from Candida albicans J-1012 (serotype A) strain cells was obtained as the residue after extracting a 105,000 × g pellet of cell homogenate with 1% Triton X-100. Incubation of this fraction with a mannopentaose, Manβ1 → 2Manα1 → (2Manα1 →)₂2Man (αβMan₅), in the presence of GDP-mannose followed by high performance liquid chromatography showed the formation of a mannohexaose. Analysis of the product by ¹H NMR indicates that αβMan₅ was changed to Manβ1 → 2Manβ1 → 2Manα1 → (2Manα1 →)₂2Man (αβMan₆). This β-1,2-mannosyltransferase (ManTase) II activity was completely inhibited by Zn²⁺ and was not restored by the addition of EDTA. The corresponding enzyme fraction from C. albicans NIH B-792 (serotype B) strain cells, the mannan of which does not possess both the αβMan₅ and αβMan₆ side chains, also exhibited the same β-1,2-ManTase II activity.

[学科分类] 生物化学/生物物理

[关键词] Candida albicans;β-1;2-Linked mannose;Mannosyltransferase;Tris;tris-hydroxymethylaminomethane;EDTA;ethylenediaminetetraacetic acid;PMSF;phenylmethylsulfonyl fluoride;HPLC;high performance liquid chromatography;PA;2-aminopyridine