Characterization of beta-1,2-mannosyltransferase in Candida guilliermondii and its utilization in the synthesis of novel oligosaccharides.
A particulate insoluble enzyme fraction containing mannosyltransferases from Candida guilliermondii IFO 10279 strain cells was obtained as the residue after extracting a 105,000 x g pellet of cell homogenate with 1% Triton X-100. Incubation of this fraction with a mannopentaose, Manalpha1-->3(Manalpha1-->6)Manalpha1-->2Manalpha1+ ++-->2Man, in the presence of GDP-mannose and Mn2+ ion at pH 6.0 gave a third type of beta-1,2 linkage-containing mannohexaose, Manbeta1-->2Manalpha1-->3(Manalpha1-->6)Manalpha1++ +-->2Manalpha1-->2Man , the structure of which was identified by means of a sequential NMR assignment. The results of a substrate specificity study indicated that the beta-1,2-mannosyltransferase requires a mannobiosyl unit, Manalpha1--> 3Manalpha1-->, at the nonreducing terminal site. We synthesized novel oligosaccharides using substrates possessing a nonreducing terminal alpha-1,3-linked mannose unit prepared from various yeast mannans. Further incubation of the enzymatically synthesized oligosaccharide with the enzyme fraction gave the following structure, Manbeta1-->2Manbeta1-->2Manalpha1-->3(Manalpha1- ->6)Manalpha1--> 2Manalpha1-->2Man, which has been found to correspond to antigenic factor 9. Incubation of Candida albicans serotype B mannan with the enzyme fraction gave significantly transformed mannan, which contains the third type of beta-1,2-linked mannose units.
Suzuki
A
A
Second Department of Hygienic Chemistry, Tohoku College of Pharmacy, 4-4-1 Komatsushima, Aoba-ku, Sendai, Miyagi 981, Japan.
Shibata
N
N
Suzuki
M
M
Saitoh
F
F
Oyamada
H
H
Kobayashi
H
H
Suzuki
S
S
Okawa
Y
Y
D000946:Antigens, Fungal / Q000096:biosynthesis; D002175:Candida / Q000201:enzymology*; D002240:Carbohydrate Sequence; D002413:Cations, Divalent / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008351:Mannans / Q000096:biosynthesis / Q000378:metabolism; D008364:Mannosyltransferases / Q000378:metabolism*; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000096:biosynthesis*
D000946:Antigens, Fungal; D002413:Cations, Divalent; D008351:Mannans; D009844:Oligosaccharides; C099269:antigenic factor 9; D008364:Mannosyltransferases; C106904:beta-1,2-mannosyltransferase IV