A realistic physical model for the so called rate promoting vibration (RPV) at enzyme action is constructed. The origin of the RPV is assumed to be an oscillating electric field produced by long-lived localized vibrational modes in protein dynamics, namely, by the so called discrete breather (DB) in secondary structure. The strength of interaction of the RPV with the reaction coordinate is eval...

Soil microorganisms can control the soil cycles of carbon (C), and depending on their C-use efficiency (CUE), these microorganisms either contribute to C stabilization in soil or produce CO2 when decomposing organic matter. However, little is known regarding the enzyme investment of microbial decomposers and the effects on their CUE. Our objective was to elucidate the strategies of litter-decom...

This paper describes the production, purification, and immobilization of l-asparaginase II (ASNase II) in chitosan nanoparticles (CSNPs). ASNase II is an effective antineoplastic agent, used in the acute lymphoblastic leukemia chemotherapy. Cloned ASNase II gene (ansB) in pAED4 plasmid was transformed into Escherichia coli BL21pLysS (DE3) competent cells and expressed under optimal conditions. ...

hydatid disease is caused by the larva of echinococcus granulosus parasite. mebendazole (mbz) is used as an alternative choice for the treatment of the disease. aspartate aminotransferase (ast) is an essential enzyme in amino acid metabolism. the aim of the present study is to evaluate the effect of mbz on ast activity of hydatid cyst parasite in order to detect enzymatic parameter for drug eff...

Bacterial L-asparaginases have been used as anti-cancer drugs for over 4 decades though presenting, along with their therapeutic efficacy, several side effects due to their bacterial origin and, seemingly, to their secondary glutaminase activity. Helicobacter pylori type II L-asparaginase possesses interesting features, among which a reduced catalytic efficiency for L-GLN, compared to the drugs...

In this paper, covalent immobilization of beta amylase enzyme on the surface of modified magnetic nano particles (ZnFe2O4@SiO2-NH2) is reported. For doing so, at first, the magnetic nanoparticles of ZnFe2O4 were synthesized by chemical co-precipitation method and then tetraethyl orthosilicate (TEOS) and 3-aminopropyltriethoxy sil...

Multienzyme processes represent an important area of biocatalysis. Their efficiency can be enhanced by optimization of the stoichiometry of the biocatalysts. Here we present a workflow for maximizing the efficiency of a three-enzyme system catalyzing a five-step chemical conversion. Kinetic models of pathways with wild-type or engineered enzymes were built, and the enzyme stoichiometry of each ...

background: aspartate transaminase (ast) is an important enzyme in parasite and liver tissue. the purpose of this investigation is to evaluate triclabendazole (tcbz) effect on ast activity of fasciola gigantica parasite. to compare of enzyme level of parasite and its host tissue, enzyme activity of f. gigantica parasite and liver tissues were also determined. method: the livers were collected f...