1yal
From Proteopedia
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CARICA PAPAYA CHYMOPAPAIN AT 1.7 ANGSTROMS RESOLUTION
Overview
The X-ray structure of chymopapain, a cysteine proteinase isolated from, the latex of the fruits of Carica papaya L., has been determined by, molecular replacement methods and refined to a conventional R factor of, 0.19 for all observed reflections in the range from 9.5 to 1.7 A, resolution. The crystals used in this study contained a unique molecular, species of chymopapain with two moles of thiomethyl attached to the two, free cysteines per mole of enzyme. A comparison is made with the other, known papaya proteinase X-ray structures: papain, caricain, and glycyl, endopeptidase. Their backbone conformations are extremely similar except, for two loop regions. Both regions are located at the surface of the, protein and far away of the active site cleft. In each X-ray structure the, same water network was found at the interface between the two domains of, the enzyme. A close examination of the active site groove showed that the, specificity restrictions dictated by the S2 subsite did not differ, significantly among the four proteinases.
About this Structure
1YAL is a Single protein structure of sequence from Carica papaya. Active as Chymopapain, with EC number 3.4.22.6 Full crystallographic information is available from OCA.
Reference
Structure of chymopapain at 1.7 A resolution., Maes D, Bouckaert J, Poortmans F, Wyns L, Looze Y, Biochemistry. 1996 Dec 17;35(50):16292-8. PMID:8973203
Page seeded by OCA on Wed Nov 21 06:39:25 2007
