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1b19
From Proteopedia
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PH AFFECTS GLU B13 SWITCHING AND SULFATE BINDING IN CUBIC INSULIN CRYSTALS (PH 5.80 COORDINATES)
Overview
Structures of porcine insulin crystals soaked in 1 M sodium sulfate at pH, 5.00, 5.53, 5.80, 6.00, 6.16, 6.26, 6.35, 6.50, 6.98 and 9.00 have been, determined at between 1.7 and 1.9 A resolution. GluB13 exhibits a single, conformation at pH </= 5.80, two conformations between pH 6.00 and 6.98, and a single conformation at pH 9.00. Between pH 6.00 and 6.98, the, conformation of GluB13 switches from one rotamer to another rotamer., Between pH 6.16 and 6.26, PheB1 undergoes a significant conformational, change. By pH 9.00 many residues have undergone relatively large shifts, and HisB10 exhibits a double conformation. As a result of the pH increase, the occupancy of the sulfate ion decreases from a maximum of 1.00 at pH, 5.00 to a minimum of 0.46 at pH 6.50. Comparison of the structures, the, observed and calculated structure factors and map correlation coefficients, indicate that the porcine insulin structure changes gradually as a, function of pH.
About this Structure
1B19 is a Protein complex structure of sequences from Sus scrofa with SO4 as ligand. Full crystallographic information is available from OCA.
Reference
Crystallographic titration of cubic insulin crystals: pH affects GluB13 switching and sulfate binding., Diao J, Acta Crystallogr D Biol Crystallogr. 2003 Apr;59(Pt 4):670-6. Epub 2003, Mar 25. PMID:12657786
Page seeded by OCA on Tue Nov 20 11:16:39 2007
