Alpha-lactalbumin possesses a distinct zinc binding site.
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Ren J, Stuart DI, Acharya KR
Alpha-lactalbumin possesses a distinct zinc binding site.
J Biol Chem. 1993 Sep 15;268(26):19292-8.
- PubMed ID
- 8366079 [ View in PubMed]
- Abstract
It has been proposed that the binding of Zn2+ to alpha-lactalbumin switches the conformation to one akin to a state intermediate in the folding of the protein. However, the high resolution x-ray crystal structure of human alpha-lactalbumin-Zn2+ complex at 1.7-A resolution (pH 7.6) does not reveal any significant change in conformation from the native state. The Zn2+ ion binds specifically in the "cleft" of alpha-lactalbumin (the region which forms the active site of the homologous protein lysozyme). This may suggest a possible role for Zn2+ binding in lactose synthase complex. The coordination of the Zn2+ ion involves a symmetry-related molecule in the crystal, the crystal contacts being stabilized by a SO4(2-) ion bound at the interface between three molecules.