1,720,985 research outputs found

    Fasciola hepatica: increase of glycogen-phosphorylase activity due to prostaglandins

    No full text
    Both prostaglandin E1 (PGE1) and prostaglandin F2α (PGF2α) stimulate the glycogen phosphorylase (EC 2.4.1.1.) activity of Fasciola hepatica. Whole or sliced parasites were incubated with PGE1 (2.8 × 10-7 and 2.8 × 10-5M) and PGF2α(2.1 × 10-7 and 2.1 × 10-5 M) and enzyme activity was measured in homogenates prepared immediately following the incubation. No substantially different effect was noted between the two assayed doses of prostaglandins. Prostaglandins appeared to be less effective in sliced parasites

    Cyclic AMP phosphodiesterase activity in Fasciola hepatica

    No full text
    The authors studied the behaviour of cyclic 3',5' AMP phosphodiesterase in the 2,000 g supernatant of the F. hepatica homogenate, under basal conditions and after addition of various substances. Dopamine markedly inhibits the enzyme activity, imidazole causes a strong activation, while serotonin, theophylline, PGE1, and PGF(2α) appear to be ineffective

    A putative protein structurally related to zygote arrest 1 (Zar1), Zar1-like, is encoded by a novel gene conserved in the vertebrate lineage

    No full text
    Identification and characterization of a bovine cDNA and the corresponding gene coding for a novel protein structurally related to Zar1, therefore called Zar1-like, are here reported for the first time. Structure of Zar1-like is similar to Zar1 gene, nevertheless they are located on distinct chromosomes. We demonstrated that the new gene as well as its genomic context are conserved along the whole vertebrate lineage. Analysis of the deduced protein primary structure showed a high conservation, among vertebrates, of the C-terminal region, where the putative presence of both zinc finger motifs and classical nuclear localization signals is also shared with Zar1. Bovine Zar1-like and the only two other available mRNA leader sequences (human and chicken) exhibit a number of upstream AUGs, suggesting that they are likely to be regulated at translational level. Expression patterns of the cattle transcripts show that Zar1-like is absent in early stages of embryo development, whereas Zar1 is expressed in matured oocytes and in in vitro produced pre-implantation embryos. In adult tissues Zar1-like transcript expression appears to be less restricted than Zar1, nevertheless, at least in bovine, both mRNAs are co-expressed in gonads, raising the question of a possible functional link

    Influence of age and cortisone treatment on two intestinal lysosomal hydrolases in young rats

    No full text
    The effects of cortisone acetate injected i.p. on acid phosphatase and beta-glucuronidase in the small intestine mucosa of two groups of rats aging 12-14 and 20-22 days are reported. The following results are obtained: a) Total and free activities of the two enzymes show age-dependent differences. b) Cortisone acetate causes a very marked decrease of the enzymic activities only in the younger rats while being ineffective on the older ones. c) The kinetics of the enzyme release at 37 degrees C appear independent either of age or of cortisone injection. d) The "in vitro" lysosome labilizing treatments are ineffective

    Stereospecificity of pig kidney and pea seedling diamino oxidases on 2-methyl-1,4-diaminobutane

    No full text
    Diamine oxidase from pea seedlings (PDAO) oxidizes both (R)- and (S)-2-methylputrescine at the less hindered C-4, whereas pig-kidney diamine oxidase (KDAO) shows a dependence on the stereochemistry of the substrate, since the (R)-isomer is oxidized at C-1 and the (S)-isomer at the less hindered amino group at C-4

    The primary structure of the flavoenzyme D-aspartate oxidase from beef kidney

    No full text
    The complete primary structure of the peroxisomal flavoenzyme D-aspartate oxidase from beef kidney has been determined by analyses of the peptides obtained through fragmentation of the carboxymethylated protein with trypsin, CNBr, heptafluorobutyric acid/CNBr and Staphylococcus aureus V8 protease. The protein consists of a single polypeptide of 338 residues, accounting for a M(r) of 37,305 for the apoprotein. A form of the enzyme lacking Lys-338 and therefore ending with Pro-337 has been detected. The N-terminal residue is blocked. Seven cysteines and no disulfide bridges are present. Residue 228 can be either Ile or Val. Thus, D-aspartate oxidase presents two types of heterogeneity in the polypeptide chain in addition to the one already described concerning the possible content of FAD or 6-hydroxyflavin adenine dinucleotide. Comparison of the primary structure of D-aspartate oxidase with other known sequences reveals that D-aspartate oxidase is homologous with D- amino acid oxidase (another flavo-oxidase) and does not present significant sequence similarities with any other protein, including flavoenzymes
    corecore