Formation of unequally labeled fructose 6-phosphate by an exchange reaction catalyzed by transaldolase.
نویسندگان
چکیده
An increasing number of investigators (2-5) have postulated the occurrence of an exchange reaction catalyzed by transaldolase between glyceraldehyde S-phosphate and fructose 6phosphate to explain the unequal labeling of the 6 carbons of hexoses which is observed in tracer experiments. Transaldolase accepts the dihydroxyacetone moiety from sedoheptulose 7-phosphate or fructose B-phosphate to form a dihydroxyacetone-enzyme intermediate (6). In the presence of an acceptor aldehyde such as glyceraldehyde 3-phosphate or erythrose 4-phosphate the dihydroxyacetone moiety is transferred to form the corresponding keto sugar-phosphate as follows:
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 236 شماره
صفحات -
تاریخ انتشار 1961