Biochem Biophys Res Commun
January 2011
tRNAs are aminoacylated with the correct amino acid by the cognate aminoacyl-tRNA synthetase. The tRNA/synthetase systems can be divided into two classes: class I and class II. Within class I, the tRNA identity elements that enable the specificity consist of complex sequence and structure motifs, whereas in class II the identity elements are assured by few and simple determinants, which are mostly located in the tRNA acceptor stem.
View Article and Find Full Text PDFBiochem Biophys Res Commun
April 2008
The tRNA(Gly)/glycyl-tRNA synthetase (GlyRS) system belongs to the so-called 'class II aminoacyl-tRNA synthetase system' in which tRNA identity elements are assured by rather few and simple determinants mostly located in the tRNA acceptor stem. Regarding evolutionary aspects, the tRNA(Gly)/GlyRS system is a special case. There exist two different types of GlyRS, namely an archaebacterial/human type and a eubacterial type reflecting an evolutionary divergence within this system.
View Article and Find Full Text PDFBiochem Biophys Res Commun
April 2008
tRNA identity elements assure the correct aminoacylation of tRNAs by the aminoacyl-tRNA synthetases with the cognate amino acid. The tRNA(Gly)/glycyl-tRNA sythetase system is member of the so-called 'class II system' in which the tRNA determinants consist of rather simple elements. These are mostly located in the tRNA acceptor stem and in the glycine case additionally the discriminator base at position 73 is required.
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2007
The X-ray structure at 2.7A resolution of the complex between the European mistletoe lectin I (Viscum album, ML-I) and the plant growth hormone, 3-(p-hydroxyphenyl)-propionic acid amide (phloretamide, PA) from xylem sap has revealed the binding of PA at the so far undescribed hydrophobic cavity located between the two subunits of this ribosome-inhibiting protein. No such cavity is observed in related lectins.
View Article and Find Full Text PDFBiochem Biophys Res Commun
November 2007
tRNA identity elements determine the correct aminoacylation by the cognate aminoacyl-tRNA synthetase. In class II aminoacyl tRNA synthetase systems, tRNA specificity is assured by rather few and simple recognition elements, mostly located in the acceptor stem of the tRNA. Here we present the crystal structure of an Escherichia coli tRNA(Gly) aminoacyl stem microhelix at 2.
View Article and Find Full Text PDFBiochem Biophys Res Commun
October 2007
Aminoacyl-tRNA synthetases catalyze the formation of aminoacyl-tRNAs. Seryl-tRNA synthetase is a class II synthetase, which depends on rather few and simple identity elements in tRNA(Ser) to determine the amino acid specificity. tRNA(Ser) acceptor stem microhelices can be aminoacylated with serine, which makes this part of the tRNA a valuable tool for investigating the structural motifs in a tRNA(Ser)-seryl-tRNA synthetase complex.
View Article and Find Full Text PDFA novel peptide was designed which possesses nanomolar affinity of less than 20 nM for streptavidin. Therefore it was termed Nano-tag and has been used as an affinity tag for recombinant proteins. The minimized version of the wild type Nano-tag is a seven-amino acid peptide with the sequence fMDVEAWL.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
January 2005
The venom of the common Indian krait (Bungarus caeruleus) contains about a dozen isoforms of phospholipase A2 (PLA2), which exist in different oligomeric forms as well as in complexes with low-molecular-weight ligands. The basic objective of multimerization and complexation is either to inactivate PLA2 in the venom for long-term storage, to generate a new PLA2 function or to make a more lethal assembly. The current isoform was isolated from the venom of B.
View Article and Find Full Text PDFThe calcium-induced formation of a complex between two isoforms of cobra venom phospholipase A2 reveals a novel interplay between the monomer-dimer and activity-inactivity transitions. The monodispersed isoforms lack activity in the absence of calcium ions while both molecules gain activity in the presence of calcium ions. At concentrations higher than 10 mg/ml, in the presence of calcium ions, they dimerize and lose activity again.
View Article and Find Full Text PDFThis is the first crystal structure of a carbohydrate induced dimer of phospholipase A(2) (PLA(2)). This is an endogenous complex formed between two PLA(2) molecules and two mannoses. It was isolated from Krait venom (Bungarus caeruleus) and crystallized as such.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
August 2004
Glutathione S-transferases (GSTs) are a family of detoxification enzymes that catalyse the conjugation of glutathione to xenobiotic and endogenous electrophilic compounds, thus facilitating their elimination from cells. The recombinant Onchocerca volvulus GST2 has been expressed in Escherichia coli, purified and crystallized by the hanging-drop vapour-diffusion technique. Two different crystal forms were grown under identical conditions.
View Article and Find Full Text PDFNucleic acid molecules in the mirror image or L-configuration are unknown in nature and are extraordinarily resistant to biological degradation. The identification of functional L-oligonucleotides called Spiegelmers offers a novel approach for drug discovery based on RNA. The sequence r(CUGGGCGG).
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
August 2003
Glutathione S-transferases (GSTs) belong to a family of detoxification enzymes that conjugate glutathione to various xenobiotics, thus facilitating their expulsion from the cells. For high-resolution crystallographic investigations, GST from the human malarial parasite Plasmodium falciparum was overexpressed in bacterial cells and crystallized using hanging-drop vapour diffusion. X-ray intensity data to 2.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
October 2002
The crystal structure of the ribosome-inactivating protein (RIP) mistletoe lectin I (ML-I) from Viscum album in complex with adenine has been refined to 1.9 A resolution. High quality crystals of the ML-I complex were obtained by the method of vapour diffusion using the high density protein crystal growth system (HDPCG) on the international space station, mission ISS 6A.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
October 2002
Phospholipase A(2) (EC 3.1.1.
View Article and Find Full Text PDFThis is the first structural observation of a plant product showing high affinity for phospholipase A(2) and regulating the synthesis of arachidonic acid, an intermediate in the production of prostaglandins. The crystal structure of a complex formed between Vipera russelli phospholipase A(2) and a plant alkaloid aristolochic acid has been determined and refined to 1.7 A resolution.
View Article and Find Full Text PDFPhospholipase A(2) is an important enzyme involved in the production of prostaglandins and their related compounds causing inflammatory disorders. Among the several peptides tested, the peptide Phe-Leu-Ser-Tyr-Lys (FLSYK) showed the highest inhibition. The dissociation constant (K(d)) for this peptide was calculated to be 3.
View Article and Find Full Text PDFThis is the first structural evidence of alpha-tocopherol (alpha-TP) as a possible candidate against inflammation, as it inhibits phospholipase A2 specifically and effectively. The crystal structure of the complex formed between Vipera russelli phospholipase A2 and alpha-tocopherol has been determined and refined to a resolution of 1.8 A.
View Article and Find Full Text PDFThe three-dimensional crystal structure of the DNA/RNA nonspecific endonuclease from Serratia marcescens was refined at the resolution of 1.07 A to R factor of 12.4% and Rfree factor of 15.
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