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1a4v
From Proteopedia
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| 1a4v, resolution 1.80Å () | |||||||||
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| Ligands: | |||||||||
| Activity: | Lactose synthase, with EC number 2.4.1.22 | ||||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
ALPHA-LACTALBUMIN
Overview
The high-resolution X-ray crystal structure of human alpha-lactalbumin (at 1.8 A) in the presence of an elevated level of calcium reveals a new secondary calcium binding site, 7.9 A away from the primary calcium binding site known in all alpha-lactalbumin structures so far. The new calcium binding site is different from the zinc and sulfate binding sites [Ren, J., et al. (1993) J. Biol. Chem. 268, 19292-19298] but shares common features with the manganese binding site as described by Gerkin [Gerkin, T. A. (1984) Biochemistry 23, 4688-4697]. The proximity of the manganese and calcium binding region and the location of the functional site on one side of the charged surface of the alpha-lactalbumin molecule suggest that these binding sites might play a role in the formation of the lactose synthase complex.
About this Structure
1A4V is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structural evidence for the presence of a secondary calcium binding site in human alpha-lactalbumin., Chandra N, Brew K, Acharya KR, Biochemistry. 1998 Apr 7;37(14):4767-72. PMID:9537992 Page seeded by OCA on Fri May 2 09:48:53 2008
