BACKGROUND Optically pure D-lactic acid (≥ 99%) is an important precursor of polylactic acid. However, there are relatively few studies on D-lactic acid fermentation compared with the extensive investigation of L-lactic acid production. Most lactic acid producers are mesophilic organisms. Optically pure D-lactic acid produced at high temperature not only could reduce the costs of sterilization ...

BACKGROUND: Fasciola species are parasitic trematode with world wide distribution that infects wild and domesticated herbivores, particularly ruminants. The aim of the present study was to investigate the intra species variations of F. gigantica, from goats and buffalos isolates in two common geographic climates of Iran. METHODS: Fasciola species were collected from goat, buffalo, sheep, and ca...

Studies on the protein-metal binding sites have mainly focused on the residues immediately surrounding the reacting substrate, cofactors, and metal ions. The contribution of residues in remote layers to the highly optimized microenvironments of catalytic active sites is not well understood. To improve our understanding, the present study examined the role of remote residues on the structure and...

To elucidate the functional role of the lysyl residue highly conserved in NAD(P)(+)-dependent amino acid dehydrogenases, Lys-80 of leucine dehydrogenase from Bacillus stearothermophilus has been mutated into Ala, Arg, or Gln. All of the mutant enzymes had markedly reduced activities in the oxidative deamination, whereas the Michaelis constants for substrate and coenzyme did not change significa...

accurate protein function prediction is an important subject in bioinformatics, especially wheresequentially and structurally similar proteins have different functions. malate dehydrogenaseand l-lactate dehydrogenase are two evolutionary related enzymes, which exist in a widevariety of organisms. these enzymes are sequentially and structurally similar and sharecommon active site residues, spati...

950 CLINICAL CHEMISTRY, Vol. 41, No. 6, 1995 creasing concentrations of these amino acids were analyzed (data not shown). These results suggest that Tyr and Leu in serum are measured as Phe to various degrees by the PDH preparations examined here. The increased utilization of Tyr and Leu by the Sigma and Biocatalysts preparations of PDH accounts for the positive biases obtained with these PDH s...

Four temporal populations of Echinostoma revolutum (ER1, ER2, ER3, ER4) were collected from domestic ducks in Khon Kaen Province, Thailand during February-October 2008. The ER1, ER2, ER3 and ER4 were collected in February, April, June and October, respectively. The 12 enzymes encoding 15 loci were examined. Two loci were found in each of 3 enzymes, namely glucose-6-phosphate dehydrogenase (G6PD...

Klebsiella aerogenes strains with reduced levels of D-amino acid dehydrogenase not only fail to use alanine as a growth substrate but also become sensitive to alanine in minimal media supplemented with glucose and ammonium. The inability of these mutant strains to catabolize the alanine provided in the medium interferes with both pathways of glutamate production. Alanine derepresses the nitroge...