In situ proteolysis for protein crystallization and structure determination.

Structural Genomics Consortium, University of Toronto, 100 College Street, Toronto, Ontario M5G 1L5, Canada.
Nature Methods (Impact Factor: 23.57). 01/2008; 4(12):1019-21. DOI: 10.1038/nmeth1118
Source: PubMed

ABSTRACT We tested the general applicability of in situ proteolysis to form protein crystals suitable for structure determination by adding a protease (chymotrypsin or trypsin) digestion step to crystallization trials of 55 bacterial and 14 human proteins that had proven recalcitrant to our best efforts at crystallization or structure determination. This is a work in progress; so far we determined structures of 9 bacterial proteins and the human aminoimidazole ribonucleotide synthetase (AIRS) domain.

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