The N-terminal truncated form of a protein synthesis enzyme, tryptophanyl-tRNA synthetase (mini-WRS), is secreted as an angiostatic ligand. However, the secretion and function of the full-length WRS (FL-WRS) remain unknown. Here, we report that the FL-WRS, but not mini-WRS, is rapidly secreted upon pathogen infection to prime innate immunity.
View Article and Find Full Text PDFHuman cytosolic aspartyl-tRNA synthetase (DRS) catalyzes the attachment of the amino acid aspartic acid to its cognate tRNA and it is a component of the multi-tRNA synthetase complex (MSC) which has been known to be involved in unexpected signaling pathways. Here, we report the crystal structure of DRS at a resolution of 2.25 Å.
View Article and Find Full Text PDFThe bifunctional glycoside hydrolase enzyme, CelM2, is able to hydrolyze glucan and xylan effectively. The crystal structure of this protein has been determined, providing useful sequential and structural information [K.H.
View Article and Find Full Text PDFIn archaea, RNA endonucleases that act specifically on RNA with bulge-helix-bulge motifs play the main role in the recognition and excision of introns, while the eukaryal enzymes use a measuring mechanism to determine the positions of the universally positioned splice sites relative to the conserved domain of pre-tRNA. Two crystallographic structures of tRNA intron-splicing endonuclease from Thermoplasma acidophilum DSM 1728 (EndA(Ta)) have been solved to 2.5-A and 2.
View Article and Find Full Text PDFRegulator of G-protein signaling 5 (RGS5), an inhibitor of Gq and Gi activation, is a member of the small RGS protein subfamily. However, despite significant process in the investigation of RGS5, no structure is yet available. In order to elucidate the mechanism of the RGS5 in G protein signaling pathway, we have overexpressed the RGS5 and Galphai(3) from human in Escherichia coli and crystallized the complex of RGS5 and Galphai(3) proteins with GDP/Mg(2+)/AlF(4)(-) at 3.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
November 2005
Fatty acid-CoA racemase plays an important role in the beta-oxidation of branched-chain fatty acids and fatty-acid derivatives as it catalyzes the conversion of several (2R)-branched-chain fatty acid-CoAs to their (2S)-stereoisomers. Fatty acid-CoA racemase from Mycobacterium tuberculosis H37Rv has been purified to homogeneity and crystallized by the hanging-drop vapour-diffusion method with polyethylene glycol 4000 as precipitant. The crystals belong to the trigonal space group P3(1) or P3(2), with unit-cell parameters a = b = 109.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
September 2005
G-protein-coupled receptors, which are major targets for drug discovery, play a major role in diverse physiological processes by relating changes in the extracellular environment to intracellular functions via activation of heterotrimeric G-proteins. However, G-protein activity is also modulated by a family of proteins called regulators of G-protein signalling (RGS), which are classified into six subfamilies. RGS10 belongs to the subgroup D/R12 and is known to act specifically on activated forms of three Galpha proteins (Galphai3, Galphaz and Galphao but not Galphas).
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