3dyb

Publication Abstract from PubMed

Proteinase K, a subtilisin-like fungal protease, was crystallized from a cocktail of small molecules containing digalacturonic acid (DGA). The crystal structure was determined to 1.32 A resolution and refined to an R factor of 0.158. The final model contained, beside the protein, two calcium ions, 379 water molecules, a molecule of DGA and a partially occupied HEPES molecule. The DGA molecule has one sugar moiety disposed exactly on a crystallographic twofold axis; the second ring was not observed. The DGA molecule is bound to two protein molecules across the twofold axis through hydrogen-bonding networks involving Ser150 and water molecules. One of the calcium-ion sites has not been reported previously. This study further illustrates the involvement of small molecules in the crystallization of macromolecules through their ability to form intermolecular lattice interactions.

High-resolution structure of proteinase K cocrystallized with digalacturonic acid.,Larson SB, Day JS, Nguyen C, Cudney R, McPherson A Acta Crystallogr Sect F Struct Biol Cryst Commun. 2009 Mar 1;65(Pt, 3):192-8. Epub 2009 Feb 12. PMID:19255463^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.