A homologue of the human site-specific prolyl cis/trans isomerase PIN1 was identified in Arabidopsis thaliana. The PIN1At gene encodes a protein of 119 amino acids that is 53% identical with the catalytic domain of the human PIN1 parvulin. Steady-state PIN1At mRNA is found in all plant tissues tested. We show by two-dimensional NMR spectroscopy that the PIN1At is a prolyl cis/trans isomerase wi...

Some asparagine and glutamine residues in proteins undergo deamidation to aspartate and glutamate with rates that depend upon the sequence and higher-order structure of the protein. Functional groups within the protein can catalyze this reaction, acting as general acids, bases, or stabilizers of the transition state. Information from specific proteins that deamidate and analysis of protein sequ...

The first step in the overall catalytic mechanism of citrate synthase is the binding and polarization of oxaloacetate. Active-site residues Arg-314, Asp-312 and His-264 in Escherichia coli citrate synthase, which are involved in oxaloacetate binding, were converted by site-directed mutagenesis to Gln-314, Asn-312 and Asn-264 respectively. The R314Q and D312N mutants expressed negligible overall...

Acrylamide is a neurotoxin and probable carcinogen formed as processing contaminant during baking production of different foodstuffs, including bread products. The amino acid asparagine the limiting substrate in Maillard reaction that produces acrylamide, so developing wheat (Triticum aestivum L.) cultivars with low free concentrations grain promising approach to reduce dietary acrylamide expos...

Asparagine (N-) linked protein glycosylation is a common and essential post-translational modification of proteins in eukaryotes, archaea and some bacteria. It plays crucial roles in protein folding and in regulation of protein function. Although the general principles of Nglycosylation have been long known, the precise details governing whether a particular asparagine residue will be N-glycosy...

Asparagine biosensor was constructed by co-immobilized anti-leukemic enzyme (L-asparaginase) and absorptive pH sensitive indicator on to plastic chips of 5mm through hydro sol-gel approach. Asparagine is used as a biomarker for detection of acute lymphoblastic leukemia. In this research work asparagine biosensor was developed focusing on L-asparaginase activity as bioassay principle. L-asparagi...

The biochemical and pharmacological effects oÃEscherichia coli asparagjnase were studied in 45 patients with leukemia and solid tumors. The drug was given in three different schedules: as a single dose, daily, or weekly. After i.v. injec tion, the peak activity obtained was dose related; the initial clearance of the enzyme from plasma followed first-order kinetics, and a half-life was about 14 ...

The biochemical and pharmacological effects oÃEscherichia coli asparagjnase were studied in 45 patients with leukemia and solid tumors. The drug was given in three different schedules: as a single dose, daily, or weekly. After i.v. injec tion, the peak activity obtained was dose related; the initial clearance of the enzyme from plasma followed first-order kinetics, and a half-life was about 14 ...

L-asparaginase is a hydrolase that catalyzes the conversion of L-asparagine--an endogenous amino acid necessary for the function of some neoplastic cells, such as lymphoblasts. In most human cells deficiency of L-asparagine can be compensated by alternative synthesis pathway through which L-asparagine is produced from aspartic acid and glutamine by asparagine synthethase. Depletion of L-asparag...

A cell-free extract from Escherichia coli containing an E. coli biotin synthase that was expressed to approx. 1% of soluble cell protein by cloning the E. coli bioB gene was used to investigate the biotin synthase reaction. The pH optimum was between 8 and 8.5, and the reaction velocity was dependent on the concentrations of dethiobiotin, cysteine, S-adenosylmethionine and asparagine. The catal...