The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Nitration of tyrosine residues is taken as evidence for intracellular formation of peroxynitrite. Cytochrome c (cyt c) can be nitrated by peroxynitrite and nitrated cyt c has been observed in cells and tissues under stress conditions. Here we studied the biochemical properties of nitrated cyt c in order to understand its potential roles in nitrative stress. Nitration of cyt c resulted in disruption...
The method of two-dimensional protein gel electrophoresis was used to evaluate the changes at the proteins level following oxygen exposure of the anaerobic sulfate-reducing bacterium Desulfovibrio vulgaris Hildenborough. Fifty-seven proteins showed significant differential expression. The cellular concentration of 35 proteins decreased while that of nineteen increased as a specific consequence of...
Amino acid transport System A (SysA) plays an important role in mediating the transplacental transfer of neutral amino acids from mother to fetus. Given that prior work has demonstrated that SysA activity is regulated, both over gestation and in response to dietary restriction during pregnancy, we examined the response of SysA activity and sodium-dependent neutral amino acid transporter (SNAT; responsible...
The Escherichia coli dnaA73, dnaA721, and dnaA71 alleles, which encode A213D, R432L, T435K substitutions, respectively, were originally isolated as extragenic suppressors of a temperature-sensitive dnaX mutant. As the A213D substitution resides in a domain that functions in ATP binding and the R432L and T435K substitutions affect residues that recognize the DnaA box motif, they might be expected to...
The structure of a thaumatin-like protein from banana (Musa acuminata) fruit, an allergen with antifungal properties, was solved at 1.7-Å-resolution, by X-ray crystallography. Though the banana protein exhibits a very similar overall fold as thaumatin it markedly differs from the sweet-tasting protein by the presence of a surface exposed electronegative cleft. Due to the presence of this electronegative...
Ammodytoxin A (AtxA) from the venom of Vipera ammodytes ammodytes belongs to group IIA secreted phospholipase A 2 (sPLA 2 ), for which the major pathologic activity is presynaptic neurotoxicity. We show here that this toxin also affects hemostasis because it exhibits strong anticoagulant activity. AtxA binds directly to human coagulation factor Xa (FXa) with K dapp of...
Synthesis of the tripeptide Z-Phe-Arg-SerNH 2 has been accomplished by a recombinant cysteine protease, cathepsin L1 from liver fluke (Fasciola hepatica), using Z-Phe-Arg-OMe as acyl acceptor and SerNH 2 as nucleophile in 0.1 M ammonium acetate pH 9.0–12.5% v/v acetonitrile at 37 °C. LC–MS detection indicated tripeptide formation after 10 min, continuing up to 5.5 h. The ester Z-Phe-Arg-OMe...
The complex formation of lipopolysaccharide (LPS) with chitosan (Ch) was demonstrated using sedimentation velocity analysis in the analytical ultracentrifuge, centrifugation in glycerol gradient and isopicnic centrifugation in cesium chloride. An addition of Ch to the Escherichia coli and Yersinia pseudotuberculosis LPS solutions was found to result in formation of the stable LPS–Ch complexes. The...
The Arabidopsis thaliana protein kinase AtPDK1 was identified as a homologue of the mammalian 3-phosphoinositide-dependent protein kinase-1 (PDK1), which is involved in a number of physiological processes including cell growth and proliferation. We now show that AtPDK1, expressed in E. coli as a recombinant protein, undergoes autophosphorylation at several sites. Using mass spectrometry, three phosphorylated...
Plasmalogens (Pls) are phospholipids containing a vinyl–ether bond at the sn-1 position of the glycerol backbone. They represent between 1/2 and 2/3 of the ethanolamine phospholipids in the brain. During aging, the Pls content in human brain falls down. However, the role of Pls metabolism-related enzymes in the regulation of Pls levels remains to be determined. Dihydroxyacetone phosphate acyltransferase...
The expression and localization of prolin-rich tyrosine kinase 2 (Pyk2) were studied in chick embryo epiphyseal chondrocytes. Two immunoreactive bands were detected in chondrocytes, a major band with an apparent M r of 123 kDa and a minor band with an apparent M r of 68 kDa. The major band appears to migrate as a doublet with apparent M r of 116/123 kDa. Increased levels of...
The biochemical defect in l-2-hydroxyglutaric aciduria is still unknown, but the mutated gene has recently been identified on chromosome 14q22. Transfection of human embryonic kidney (HEK) cells with a cDNA encoding the product of the human gene led to a>15-fold increase in l-2-hydroxyglutarate dehydrogenase activity. The overexpressed enzyme had similar biochemical characteristics (including sensitivity...
The N-acetyl-d-galactosamine (GalNAc) transport system of Escherichia coli K92 was studied when the bacterium was grown in a chemically defined medium containing GalNAc as a carbon source. Kinetic measurements were carried out in vivo at 37 °C in 25 mM phosphate buffer, pH 7.0. Under these conditions, the uptake rate was linear for at least 3 min and the calculated K m for GalNAc was 3 μM...
Hepcidin is a liver-expressed antimicrobial and iron regulatory peptide. A number of studies have indicated that hepcidin is important for the correct regulation of body iron homeostasis. The aims of this study were to analyse the expression, trafficking and regulation of human hepcidin in an in vitro cell culture system. Human hepcidin was transfected into human embryonic kidney cells. Immunofluorescence...
We show here that serum of piaussu, a Neotropical characin fish, has the highest butyrylcholinesterase activity so far described for humans and fish. To clarify whether this cholinesterase could protect piaussu against anticholinesterase pesticides by scavenging organophosphates, we purified it 1700-fold, with a yield of 80%. Augmenting concentrations (from 0.01 to 20 mM) of butyrylthiocholine activated...
In investigations aimed at characterizing snake venom clot-dissolving enzymes, we have purified a fibrinolytic proteinase from the venom of Bothrops leucurus (white-tailed jararaca). The proteinase was purified to homogeneity by a combination of molecular sieve chromatography on Sephacryl S-200 and ion-exchange chromatography on CM Sepharose. The enzyme called leucurolysin-a (leuc-a), is a 23 kDa...
We identified a T-to-C mutation 2 nucleotides (nt) upstream from the AG in a GT-AG intron between exons 2 and 3 in the human T-cell leukemia virus type I (HTLV-I) tax mRNA. This mutation resulted in the preferential usage of an alternative splice site, causing a 75-nt elongation of tax mRNA and reduced production of viral antigens. When the clone containing this T-to-C mutation was reverted to the...
Fluorescence enhancement effect of the morin–Al 3+ –cetyltrimethylammonium bromide (CTAB)–bovine serum albumin (BSA) system is reported here and the interaction mechanism is studied using fluorescence, resonance light scattering (RLS), absorption spectroscopy, Far-UV circular dichroism (CD) spectrum and small angle X-ray scattering (SAXS) measurement. It is considered that protein can bind...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.