3rbt

Publication Abstract from PubMed

Glutathione transferases (GSTs) are ubiquitous detoxification enzymes that conjugate hydrophobic xenobiotics with reduced glutathione. The silkworm Bombyx mori encodes four isoforms of GST Omega (GSTO), featured with a catalytic cysteine, except that bmGSTO3-3 has an asparagine substitution of this catalytic residue. Here, we determined the 2.20-A crystal structure of bmGSTO3-3, which shares a typical GST overall structure. However, the extended C-terminal segment that exists in all the four bmGSTOs occupies the G-site of bmGSTO3-3 and makes it unworkable, as shown by the activity assays. Upon mutation of Asn29 to Cys and truncation of the C-terminal segment, the in vitro GST activity of bmGSTO3-3 could be restored. These findings provided structural insights into the activity regulation of GSTOs.

Structure-guided activity restoration of the silkworm glutathione transferase Omega GSTO3-3.,Chen BY, Ma XX, Guo PC, Tan X, Li WF, Yang JP, Zhang NN, Chen Y, Xia Q, Zhou CZ J Mol Biol. 2011 Sep 16;412(2):204-11. Epub 2011 Jul 22. PMID:21816159^[1]

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