Identification of an Allosteric Pathway in the Regulation of alpha-Isopropylmalate Synthase from Mycobacterium Tubercubsis by Solution-phase H/D Exchange FT-ICR MS

摘要

HDX FT-ICR MS results showed higher flexibility of the linker domain in the Y410F MtIPMS that is insensitive to effector binding than in the wild-type MtIPMS, indicating loss of inhibition signal transduction between the regulatory domain and the catalytic domain in the mutant. These results comprise one of the first reports of an experimentally mapped allosteric mechanism in a large protein (72 kDa). Solution-phase HDX coupled with high resolution FT-ICR MS is an efficient and accurate way to study protein conformation and function in systems that are intractable in other methods. Results from HDX MS are complementary to results from X-ray crystallography and biochemical studies.