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1ump
From Proteopedia
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. 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 Sat May 3 11:26:12 2008
