The thermostability of Flavobacterium meningosepticum glycerol kinase was increased by the change from Ser329 to Asp [Protein Eng., 14, 663-667 (2001)]. Based on a three-dimensional structure model of the mutant, we have postulated that a new charged-neutral hydrogen bond was formed between Asp329 and Ser414, and the formation of the hydrogen bond contributed to the stabilization of the tertiar...

in this study, the interaction of various concentrations of cadmium sulfate with peroxidase (e.c 1.11.1.7) was investigated in different temperatures (25-35 °c). for this purpose thermostability, spectrophotometry, spectroflorimetry and kinetics studies were done to obtain thermodynamic parameters including ∆g°, ∆h°m, ∆s°m, tm and also kinetics parameters including vmax and km. the results show...

in this study, the ashes of poplar tree leaves are applied as an efficient, accessible and inexpensive biosorbent for the removal of heavy metals pb2+ and cu+2 in aqueous solutions. in the adsorption processes, the success of the ions removal highly depends on the level of several experimental factors such as ph, contact time, adsorbent dosage and temperature. therefore, a genuine statistical e...

A beta-glycosidase of a thermophile, Thermus thermophilus, belonging to the glycoside hydrolase family 1, was cloned and overexpressed in Escherichia coli. The purified enzyme (Ttbetagly) has a broad substrate specificity towards beta-D-glucoside, beta-D-galactoside and beta-D-fucoside derivatives. The thermostability of Ttbetagly was exploited to study its kinetic properties within the range 2...

microbial cells are producers of natural polymers present in plant cells. production of pullulan (an extracellular microbial polysaccharide) by aureobasidium pullularia pullulans (p. pullulans) was studied under fermentation conditions, and kinetic parameters were determined. pullulan formation obeyed a growth and non-growth associated term. phb (polyhydroxybutyrates) an intracellular biopolyme...

The barley b-amylase I (Bmy1) locus encodes a starch breakdown enzyme whose kinetic properties and thermostability are critical during malt production. Studies of allelic variation at the Bmy1 locus have shown that the encoded enzyme can be commonly found in at least three distinct thermostability classes and demonstrated the nucleotide sequence variations responsible for such phenotypic differ...

Deficiency of human erythrocyte isozyme (RPK) is, together with glucose-6-phosphate dehydrogenase deficiency, the most common cause of the nonspherocytic hemolytic anemia. To provide a molecular framework to the disease, we have solved the 2.7 A resolution crystal structure of human RPK in complex with fructose 1,6-bisphosphate, the allosteric activator, and phosphoglycolate, a substrate analog...

To elucidate determinants of differences in thermostability between mesophilic and psychrophilic monomeric isocitrate dehydrogenases (IDHs) from Azotobacter vinelandii (AvIDH) and Colwellia maris (CmIDH), respectively, chimeric enzymes derived from the two IDHs were constructed based on the recently resolved three-dimensional structure of AvIDH, and several characteristics of the two wild-type ...

Inherited pyrimidine 5'-nucleotidase type I (P5'N-1) deficiency is the third most common erythrocyte enzymopathy that causes hemolysis. Fourteen different mutations have been identified to date. We have investigated the molecular bases of the disease by studying the biochemical properties of the recombinant wild-type human enzyme and 4 variant proteins (D87V, L131P, N179S, and G230R) bearing mi...

microwave assisted fluidized bed drying is a novel drying technique which reduces drying time and yields higher quality products. in this study the effect of this method on color changes of whole and cut hazelnut kernels was investigated. the parameters of color and resulting total color change, chroma, hue angle and browning index were also calculated during drying in three temperatures (40, 5...