TY - JOUR
T1 - In vitro hydrolysis of oligomannose-type sugar chains by an α-1,2-mannosidase from microsomes of developing castor bean cotyledons
AU - Yoshinobu Kimura, Kimura
AU - Osamu Yamaguchi, Yamaguchi
AU - Hiroshi Suehisa, Suehisa
AU - Shigeaki Takagi, Takagi
N1 - Funding Information:
The authors are grateful to Professor S. Hase, Osaka University, for gifts of some authentic PA-sugar chains. This work was supported in part by a Grant-in-Aid (No. 01760075) for Scientific Research from the Ministry of Education, Science, and Culture of Japan.
PY - 1991/9/2
Y1 - 1991/9/2
N2 - An α-1,2-mannosidase involved in the processing of N-linked oligosaccharides was prepared from the microsomal fraction of developing castor bean cotyledons. The processing α-mannosidase was solubilized with 1.0% Triton X-100 and purified by ion-exchange chromatography followed by two gel filtration steps. The enzyme obtained could convert Man9GlcNAc2-PA to Man5GlcNAc2-PA, but this enzyme was inactive with Man5GlcNAc2-PA, Man4GlcNAc2-PA, and p-nitrophenyl-α-d-mannopyranoside. The enzyme was optimally active between pH 5.5-6.0. The processing mannosidase was inhibited by deoxymannojirimycin, EDTA, and Tris ions but not by swainsonine. Structural analyses of the mannose-trimming intermediates produced by the α-mannosidase revealed that specific intermediates were formed during conversion of Man9GlcNAc2-PA to Man5GlcNAc2-PA.
AB - An α-1,2-mannosidase involved in the processing of N-linked oligosaccharides was prepared from the microsomal fraction of developing castor bean cotyledons. The processing α-mannosidase was solubilized with 1.0% Triton X-100 and purified by ion-exchange chromatography followed by two gel filtration steps. The enzyme obtained could convert Man9GlcNAc2-PA to Man5GlcNAc2-PA, but this enzyme was inactive with Man5GlcNAc2-PA, Man4GlcNAc2-PA, and p-nitrophenyl-α-d-mannopyranoside. The enzyme was optimally active between pH 5.5-6.0. The processing mannosidase was inhibited by deoxymannojirimycin, EDTA, and Tris ions but not by swainsonine. Structural analyses of the mannose-trimming intermediates produced by the α-mannosidase revealed that specific intermediates were formed during conversion of Man9GlcNAc2-PA to Man5GlcNAc2-PA.
KW - (R. communis)
KW - Pyridyl amino derivative
KW - Sugar chain processing
KW - α-1,2-Mannosidase
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U2 - 10.1016/0304-4165(91)90067-Q
DO - 10.1016/0304-4165(91)90067-Q
M3 - Article
C2 - 1832562
AN - SCOPUS:0025883304
SN - 0304-4165
VL - 1075
SP - 6
EP - 11
JO - Biochimica et Biophysica Acta - General Subjects
JF - Biochimica et Biophysica Acta - General Subjects
IS - 1
ER -