| Autor: |
KATO, Masaru, TAKEHARA, Kyoko, KETTOKU, Masako, KOBAYASHI, Kazuo, SHIMIZU, Toshiyuki |
| Zdroj: |
Bioscience, Biotechnology, and Biochemistry; January 2000, Vol. 64 Issue: 2 p319-326, 8p |
| Abstrakt: |
A glycosyltrehalose-producing enzyme from Sulfolobus solfataricusKM1 catalyzes a conversion of maltooligosaccharides to glycosyltrehaloses and also hydrolyzes maltooligosaccharides to liberate glucose, as a side reaction. From the sum of the conversion and hydrolysis reaction rates, the rate parameters involved in the “splitting” of the α-1,4 glucosidic linkage were calculated. From the data obtained, the subsite structure for maltooligosaccharides was identified. From the analysis of the hydrolysate of maltotriose in [18O] labeled H2O, the hypothesis of the C1-O bond splitting and the formation of a glycosyl (maltosyl)-enzyme intermediate was strongly supported. From the analysis of the reaction product in the presence of [3H] labeled glucose, the occurrence of intermolecular transglycosylation was confirmed. These data strongly support the suggestion that the catalytic mechanism of this enzyme is a transglycosylation. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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