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Alignment Analysis (alignment + analysis)
Selected AbstractsMolecular characterization, immunohistochemical localization and expression of a ribosomal protein L17 gene from Apis cerana ceranaARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2010Fei Meng Abstract Ribosomal protein L17 (RPL17) is a core protein of the large (60S) ribosomal subunit and plays an important role in protein synthesis. In this report, a RPL17 gene was isolated from Apis cerana cerana, designated as AccRPL17. Alignment analysis showed that AccRPL17 exhibits high homology to other known RPL17s. Moreover, genomic sequence analysis revealed that five exons are splitted by four introns, and the position of the first intron is comparatively conservative, being localized in the 5, untranslated region. Partial putative cis -acting elements related to development were also examined. Quantitative real-time PCR showed that the highest mRNA level was detected in larvae on the fifth day. Simultaneously, immunohistochemical localization showed that AccRPL17 is primarily concentrated in muscular tissues, stigma, body wall, and the surrounding of the eye in the fifth-instar larvae. Further studies suggested that AccRPL17 might be involved in responses to abiotic stresses. This is a report attempting to analyze the expression and distribution of RPL17 in A. cerana cerana. These results indicated that AccRPL17 might play an important role in insect development, and the importance of AccRPL17 in participating in abiotic stresses is discussed. © 2010 Wiley Periodicals, Inc. [source] Substrate specificity and inhibition of brassinin hydrolases, detoxifying enzymes from the plant pathogens Leptosphaeria maculans and Alternaria brassicicolaFEBS JOURNAL, Issue 24 2009M. Soledade C. Pedras Blackleg (Leptosphaeria maculans and Leptosphaeria biglobosa) and black spot (Alternaria brassicicola) fungi are devastating plant pathogens known to detoxify the plant defence metabolite, brassinin. The significant roles of brassinin as a crucifer phytoalexin and as a biosynthetic precursor of several other plant defences make it important in plant fitness. Brassinin detoxifying enzymes produced by L. maculans and A. brassicicola catalyse the detoxification of brassinin by hydrolysis of its dithiocarbamate group to indolyl-3-methanamine. The purification and characterization of brassinin hydrolases produced by L. maculans (BHLmL2) and A. brassicicola (BHAb) were accomplished: native BHLmL2 was found to be a tetrameric protein with a molecular mass of 220 kDa, whereas native BHAb was found to be a dimeric protein of 120 kDa. Protein characterization using LC-MS/MS and sequence alignment analyses suggested that both enzymes belong to the family of amidases with the catalytic Ser/Ser/Lys triad. Furthermore, chemical modification of BHLmL2 and BHAb with selective reagents suggested that the amino acid serine was involved in the catalytic activity of both enzymes. The overall results indicated that BHs have new substrate specificities with a new catalytic activity that can be designated as dithiocarbamate hydrolase. Investigation of the effect of various phytoalexins on the activities of BHLmL2 and BHAb indicated that cyclobrassinin was a competitive inhibitor of both enzymes. On the basis of pH dependence, sequence analyses, chemical modifications of amino acid residues and identification of headspace volatiles, a chemical mechanism for hydrolysis of the dithiocarbamate group of brassinin catalysed by BHLmL2 and BHAb is proposed. The current information should facilitate the design of specific synthetic inhibitors of these enzymes for plant treatments against blackleg and black spot fungal infections. [source] Functional role of fumarate site Glu59 involved in allosteric regulation and subunit,subunit interaction of human mitochondrial NAD(P)+ -dependent malic enzymeFEBS JOURNAL, Issue 4 2009Ju-Yi Hsieh Here we report on the role of Glu59 in the fumarate-mediated allosteric regulation of the human mitochondrial NAD(P)+ -dependent malic enzyme (m-NAD-ME). In the present study, Glu59 was substituted by Asp, Gln or Leu. Our kinetic data strongly indicated that the charge properties of this residue significantly affect the allosteric activation of the enzyme. The E59L enzyme shows nonallosteric kinetics and the E59Q enzyme displays a much higher threshold in enzyme activation with elevated activation constants, KA,Fum and ,KA,Fum. The E59D enzyme, although retaining the allosteric property, is quite different from the wild-type in enzyme activation. The KA,Fum and ,KA,Fum of E59D are also much greater than those of the wild-type, indicating that not only the negative charge of this residue but also the group specificity and side chain interactions are important for fumarate binding. Analytical ultracentrifugation analysis shows that both the wild-type and E59Q enzymes exist as a dimer,tetramer equilibrium. In contrast to the E59Q mutant, the E59D mutant displays predominantly a dimer form, indicating that the quaternary stability in the dimer interface is changed by shortening one carbon side chain of Glu59 to Asp59. The E59L enzyme also shows a dimer,tetramer model similar to that of the wild-type, but it displays more dimers as well as monomers and polymers. Malate cooperativity is not significantly notable in the E59 mutant enzymes, suggesting that the cooperativity might be related to the molecular geometry of the fumarate-binding site. Glu59 can precisely maintain the geometric specificity for the substrate cooperativity. According to the sequence alignment analysis and our experimental data, we suggest that charge effect and geometric specificity are both critical factors in enzyme regulation. Glu59 discriminates human m-NAD-ME from mitochondrial NADP+ -dependent malic enzyme and cytosolic NADP+ -dependent malic enzyme in fumarate activation and malate cooperativity. [source] Glycolysis in Ustilago maydisFEMS YEAST RESEARCH, Issue 8 2008Emma Saavedra Abstract The kinetic parameters of the 10 glycolytic enzymes and glycolytic fluxes were determined for the first time in Ustilago maydis. Enzyme activities in yeast grown in minimal medium and harvested in the stationary stage were twofold higher than those from yeast grown in rich medium. In contrast, in yeast harvested in the exponential stage, the enzyme activities were higher in cells grown in rich medium. Phosphofructokinase activity was the lowest in the four culture conditions analyzed, suggesting that this enzyme is a flux-controlling step in U. maydis glycolysis. The Vmax and Km values of hexokinase and pyruvate kinase were similar under all conditions. The results revealed that U. maydis aldolase belongs to the class II type of metalo-aldolases. 3-Phosphoglycerate mutase (PGAM) activity was 2,3-bisphosphoglycerate cofactor independent, which contrasted with the cofactor dependency predicted by the amino acid sequence alignment analysis. Pyruvate was secreted by U. maydis yeast in the presence and absence of external glucose. The glycolytic enzyme activities in the U. maydis mycelial form were similar to those found in yeast, except for one order of magnitude higher phosphofructokinase and PGAM activities, thus suggesting differences in the glycolysis regulatory mechanisms between the two cellular forms. [source] Diversification in MHC class II invariant chain-like proteins among fishesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2004M. Sakai Summary The major histocompatibility complex (MHC) class II invariant chains are important for an efficient and complete presentation of antigens by MHC class II molecules. Invariant chain-like proteins (Iclp) 1 and 2 were identified by expressed sequence tag analysis from cDNA library of common carp head kidney (HK) stimulated with concanavalin A and lipopolysaccharide. The sequences were 1043 and 1016 bp in length encoding 234 and 198 amino acid proteins, respectively. Based on their predicted structure, the genes harboured transmembrane domain (TMD) and Tg (thyroglobulin) type 1 domains. Expression analysis revealed that both genes were expressed in normal tissues of HK, intestine, brain and gill. By database search, similar homologues were found in Atlantic salmon, fugu and catfish. Phylogenetic and alignment analysis indicate diversity among fish Iclps. [source] | ||||||||||