3vk9

Publication Abstract from PubMed

BACKGROUND: Glutathione transferase (GST) catalyzes glutathione conjugation, a major detoxification pathway for xenobiotics and endogenous substances. Here, we determined the crystal structure of a Delta-class GST from Bombyx mori (bmGSTD) to examine its catalytic residues. METHODS: The three-dimensional structure of bmGSTD was resolved by the molecular replacement method and refined to a resolution of 2.0A. RESULTS: Structural alignment with a Delta-class GST of Anopheles gambiae indicated that bmGSTD contains 2 distinct domains (an N-terminal domain and a C-terminal domain) connected by a linker. The bound glutathione localized at the N-terminal domain. Putative catalytic residues were changed to alanine by site-directed mutagenesis, and the resulting mutants were characterized in terms of catalytic activity using glutathione and 1-chloro-2,4-dinitrobenzene, a synthetic substrate of GST. Kinetic analysis of bmGSTD mutants indicated that Ser11, Gln51, His52, Ser67, and Arg68 are important for enzyme function. GENERAL SIGNIFICANCE: These results provide structural insights into the catalysis of glutathione conjugation in B. mori by bmGSTD.

Structural basis for catalytic activity of a silkworm Delta-class glutathione transferase.,Yamamoto K, Usuda K, Kakuta Y, Kimura M, Higashiura A, Nakagawa A, Aso Y, Suzuki M Biochim Biophys Acta. 2012 Oct;1820(10):1469-74. Epub 2012 May 8. PMID:22579926^[1]

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