๐”– Bobbio Scriptorium
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3-Oxoecdysteroid reductases in Manduca sexta midgut

โœ Scribed by Gunter F. Weirich; James A. Svoboda

Publisher
John Wiley and Sons
Year
1992
Tongue
English
Weight
640 KB
Volume
21
Category
Article
ISSN
0739-4462

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โœฆ Synopsis

The 80,000g supernatant of larval midgut homogenates of the tobacco hornworm, Manduca sexta, was fractionated by affinity chromatography on Blue Sepharose CLdB and by anion exchange chromatography on Q Sepharose. Both methods resolved one major 3-oxoecdysteroid 3a-reductase and three major 3-oxoecdysteroid 3P-reductases. The 3P-reductases reacted only with NADPH as cosubstrate. The ?a-reductase was active with both NADPH and NADH, and the NADPH/NADH activity ratio increased with the NaCl concentration (0-0.5 M) in the incubation mixtures. The 3a-reductase and one of the 3P-reductases showed very similar chromatographic properties, and their isoelectric points were 5.2 and 5.8, respectively. o 1992 WiIey-Liss, Inc.

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