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1ump
From Proteopedia
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GEOMETRY OF TRITERPENE CONVERSION TO PENTACARBOCYCLIC HOPENE
Overview
The membrane protein squalene-hopene cyclase was cocrystallized with, 2-azasqualene and analyzed by X-ray diffraction to 2.13 A resolution. The, conformation of this close analog was clearly established, and it agreed, with the common textbook presentation. The bound squalene undergoes only, small conformational changes during the formation of rings A through D, thus requiring no intermediate. However, ring E formation is hindered by, an entropic barrier, which may explain its absence in the steroids. The, structure analysis revealed a mobile region between the active center, cavity and the membrane, which may melt, opening a passage for squalene, and hopene.
About this Structure
1UMP is a Single protein structure of sequence from Alicyclobacillus acidocaldarius with C8E and SQA as ligands. Active as Squalene--hopene cyclase, with EC number 5.4.99.17 Structure known Active Site: AC1. Full crystallographic information is available from OCA.
Reference
Conversion of squalene to the pentacarbocyclic hopene., Reinert DJ, Balliano G, Schulz GE, Chem Biol. 2004 Jan;11(1):121-6. PMID:15113001
Page seeded by OCA on Mon Nov 5 17:06:35 2007
