It has been suggested that the reduced function allele with reduced cytochrome P450 (CYP) 2D6 activity, CYP2D6*10, is associated with the interindividual differences in the plasma paroxetine concentrations, but there is no data presently available regarding the influence of the CYP2D6*10 polymorphism on the pharmacokinetic parameters, eg, Michaelis-Menten constant (Km) and maximum velocity (Vma...

Accurate modeling of enzyme activity and stability is an important goal of the protein engineering community. However, studies seeking to evaluate current progress are limited by small data sets of quantitative kinetic constants and thermal stability measurements. Here, we report quantitative measurements of soluble protein expression in E. coli, thermal stability, and Michaelis-Menten constant...

The rate constant for free fatty acid influx (k1) was studied in normal and ischemic myocardium. In 15 normal subjects and 30 patients with coronary artery disease, 201Tl and 15-(p-123I-iodophenyl)-pentadecanoic acid (IPPA) were administered during exercise under fasting conditions and at rest. In 10 patients, the study was repeated after percutaneous transluminal coronary angioplasty; in three...

The kinetics of the action of fumarase on L-malate and fumarate were investigated at constant ionic strength. This was done to evaluate reports that fumarase follows simple Michaelis-Menten kinetics. However, when pH, buffer concentration and ionic strength are all maintained at constant values, the Lineweaver-Burk plots exhibit pronounced downward curvature, characteristic of negative kinetic ...

One-step enzyme purification and immobilization were developed based on simple adsorption of a family 3 cellulose-binding module (CBM)-tagged protein on the external surface of high-capacity regenerated amorphous cellulose (RAC). An open reading frame (ORF) Cthe0217 encoding a putative phosphoglucose isomerase (PGI, EC 5.3.1.9) from a thermophilic bacterium Clostridium thermocellum was cloned a...

A relevant and current aspect of wastewater treatment systems is related to the processes nitrogen cycle that results in its elimination gaseous forms. In present study, we report first measurements nitrate-reducing rate (NRR) at lab-scale, using flow-through reactor technique with sludge a sewage stabilization pond system located Patagonia (Argentina). Sludge was collected from Inlet Outlet ar...

The uptake of amethopterin-3H by L1210 leukemia cells appears to be mediated, probably, via an active transport mechanism. Uptake occurred against a concentration gradient, was temperature dependent, required a readily available source of energy, exhibited a pH optimum of 7.6 and conformed to Michaelis-Menten kinetics. The maximum intracellular concen tration of unbound amethopterin-3H accumula...

The formation of trifluoroacetic acid (TFAA) from halothane under aerobic conditions and that of chlorotrifluoroethane (CTE) and chlorodifluoroethylene (CDE) from halothane under anaerobic conditions were studied using guinea pig liver microsomes. The formation of TFAA was inhibited by specific inhibitors of cytochrome P450 (P450), such as carbon monoxide and metyrapone and was dependent upon P...

The uptake of amethopterin-3H by L1210 leukemia cells appears to be mediated, probably, via an active transport mechanism. Uptake occurred against a concentration gradient, was temperature dependent, required a readily available source of energy, exhibited a pH optimum of 7.6 and conformed to Michaelis-Menten kinetics. The maximum intracellular concen tration of unbound amethopterin-3H accumula...