Structure of the cystathionine γ-synthase MetB fromMycobacterium ulcerans

Abstract

PDB References: MyulA.00906.a, 3qi6; 3qhx.Cystathionine -synthase (CGS) is a transulfurication enzyme that catalyzes the first specific step in l-methionine biosynthesis by the reaction of O 4 -succinyll-homoserine and l-cysteine to produce l-cystathionine and succinate. Controlling the first step in l-methionine biosythesis, CGS is an excellent potential drug target. Mycobacterium ulcerans is a slow-growing mycobacterium that is the third most common form of mycobacterial infection, mainly infecting people in Africa, Australia and Southeast Asia. Infected patients display a variety of skin ailments ranging from indolent non-ulcerated lesions as well as ulcerated lesions. Here, the crystal structure of CGS from M. ulcerans covalently linked to the cofactor pyridoxal phosphate (PLP) is reported at 1.9 Å resolution. A second structure contains PLP as well as a highly ordered HEPES molecule in the active site acting as a pseudo-ligand. These results present the first structure of a CGS from a mycobacterium and allow comparison with other CGS enzymes. This is also the first structure reported from the pathogen M. ulcerans.

Catalytic specificity of the Lactobacillus plantarum cystathionine γ-lyase presumed by the crystallographic analysis

“…The obtained crystal structures are very similar to the closed forms of other CGL enzymes, including prokaryotic ( PDB IDs : 4L0O from Helicobacter pylori , 6K1N from Stenotrophomonas maltophilia , 4IYO from Xanthomonas oryzae 34 , and 6KHQ from Staphylococcus aureus 35 ) and eukaryotic ones ( PDB IDs : 1N8P from yeast 4 and 2NMP from human 5 ). In addition, the 3QI6 structure from Mycobacterium ulcerans 36 and the 6CJA structure from Legionella pneumophila are deposited as cystathionine γ-synthase (CGS) and CBL, respectively, they are likely to be CGL on the basis of the high structural similarity to the L. plantarum CGL. The L. plantarum CGL forms a tetramer in the crystal (Fig.…”

Biocatalytic Synthesis of α-Amino Ketones

“…Select reactions mediated by PLP-dependent proteins: threonine aldolase 13 , Ala aminotransferase 14 , Ala racemase 15 , His decarboxylase 16 , Trp synthase 17 , cystathionine gamma synthase. 18 …”

The hyperthermophilic cystathionine γ-synthase from the aerobic crenarchaeonSulfolobus tokodaii: expression, purification, crystallization and structural insights

“…1). The phenolate anion of the Tyr residue in the vicinity of the PLP cofactor accepts a proton from the -amino group of a substrate, and the lone pair on the N atom then attacks the PLP (Clausen et al, 1998;Steegborn et al, 1999;Clifton et al, 2011); mutation of Tyr to Phe drastically decreases the activities of E. coli CGS (Jaworski et al, 2012) and other PLP enzymes (Inoue et al, 2000;Sato et al, 2008). In this work, recombinant StCGS enzyme was crystallized under different pH and temperature conditions in order to understand the pH and temperature dependence of the activity of StCGS based on its X-ray structures.…”