Fructose is utilized as a common sweetener in many food industries. Today, a large amount of HFCS (high fructose corn syrup, an equilibrium mixture of glucose and fructose) is produced by glucose isomerase, immobilized enzymes from corn starch. There are a lot of date palms in Iran. Date is a favorable source of carbohydrates, and a suitable source for HFDS (high fructose date syrup) production...

Approximately 260 Streptomyces strains were isolated from neutral pH farmland soil and evaluated for their ability to produce glucose isomerase. The number of acidophilic Streptomyces organisms growing at pH 4.0 was low, i.e., 10 organisms per g of soil. All of the isolates showed glucose isomerase activity when they were grown in a medium containing d-xylose, an inducer for glucose isomerase. ...

The sugar nucleotide GDP-mannose is essential for Trypanosoma brucei. Phosphomannose isomerase occupies a key position on the de novo pathway to GDP-mannose from glucose, just before intersection with the salvage pathway from free mannose. We identified the parasite phosphomannose isomerase gene, confirmed that it encodes phosphomannose isomerase activity and localized the endogenous enzyme to ...

Properties were determined of the glucose isomerase from Streptomyces phaeochromogenes NRRL B-3559. The enzyme exhibited a temperature optimum of 80 C and a pH optimum of about 8. The effect of various buffers on activity of the enzyme and the optimum pH were studied. Michaelis constants for glucose and Mg(2+) were 0.25 and 0.025 m, respectively. Co(2+) enhanced enzyme activity. A functional po...

Glucose isomerases produced by Thermoanaerobacter strain B6A and Clostridium thermosulfurogenes strain 4B were purified 10-11-fold to homogeneity and their physicochemical and catalytic properties were determined. Both purified enzymes displayed very similar properties (native Mr 200,000, tetrameric subunit composition, and apparent pH optima 7.0-7.5). The enzymes were stable at pH 5.5-12.0, an...

Down-regulation ("curb") of hexose transport in Chinese hamster lung fibroblasts has been studied in a metabolic mutant highly defective in phosphoglucose isomerase (PGI; glucosephosphate isomerase; D-glucose-6-phosphate ketol-isomerase, EC 5.3.1.9). In the parental strain (PGI+) glucose as well as glucosamine and mannose were able to elicit a curb of the hexose transport system. In the PGI mut...

Enzymes acting on the first carbon of n-glucose are specific for a particular anomer. Two well known cases are the glucose oxidase from Penicillium not&urn and glucose dehydrogenase from liver, both of them specific for @-glucose1 (I, 2). It is likely that enzymes acting at the same level of n-glucose 6-phosphate will also have an anomeric specificity, but there was no definite information on t...

In this study, phosphoenolpyruvate and erythrose-4-phosphate are efficiently supplied by collaborative design of Embden-Meyerhof-Parnas (EMP) pathway pentose phosphate (PP) in Escherichia coli, thus increasing the L-tryptophan production. Firstly, effects disrupting EMP on production were studied, results indicated that strain with deletion phosphofructokinase A (i.e., E. coli JW-5 ΔpfkA) produ...