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Nadzarah A. Wahab - One of the best experts on this subject based on the ideXlab platform.
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Comparison of the Amino Acid Sequence of L–Mandelate Dehydrogenase From Rhodotorula Graminis With Other L–2–Hydroxyacid Dehydrogenase Enzyme and its Primary Structure Prediction
Jurnal Teknologi, 2012Co-Authors: Rosli Md. Illias, Graeme A. Reid, Nadzarah A. WahabAbstract:Perbandingan struktur primer L(+)–mendalate dehydrogenase (L–MDH) daripada yis Rhodotorula graminis dengan protein lain di dalam bank data protein menunjukkan persamaan di antara protein ini dengan kumpulan enzim L–2–hidroksiasid dehidrogenase. LMDH daripada R. graminis mempamerkan kesamaan antara 26–42% kepada L–Lactate dehidrogenase daripada Sacchomoryces cerevisiae, L–Lactate dehidrogenase daripada Hansenula anomala, glikolat oksida daripada bayam, L–laktat dehidrogenase daripada Escherichia coli, LMDH daripada Psedomonas putida dan laktat–2 monooksigenase daripada Mycobakterium smegmatis. Asid amino yang penting secara strukturnya bagi LMDH diramalkan secara perbandingan dengan bahagian penting domain sitokram dan domain perlekatan FMN yang diperoleh daripada struktur tiga dimensi L–laktat dehidrogenase daripada Sacchoromyces cerevisiae. Kata kunci: L-MDH; Rhodotorula gramisis; L(+)-mandalate dehydrogenase; asid amino,flavocytochrome b2 A comparison of the primary structure or L–mandelate dehydrogenase (L–MDH) from Rhodotorula graminis with other proteins from the protein databank suggests that there is similarity between this protein and L–2–hydroxyacid dehydrogenase enzymes. R graminis LMDH exhibits 26–42% identity to L–Lactate dehydrogenase from Saccharomyces cerevisiae, L–Lactate dehydrogenase from Hansenula anomala, glycolate oxidase from spinach, L–Lactate dehydrogenase from Escherichia coli, L–mandelate dehydrogenase from Pseudomonas putida and Lactate–2–Monooxygenase from Mycobacterium smegmatis. Structurally conserved amino acids are predicted from LMDH sequences corresponding to important regions of the cytochrome and FMN–binding domain defined from the known three–dimensional structure of the L–Lactate dehyrogenase from Sacchoromyces cerevisiae. Key words: L-MDH; Rhodotorula graminis; L-mandelate dehydrogenase; amino acid;flavocytochrome b2
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COMPARISON OF THE AMINO ACID SEQUENCE OF L-MANDELATE DEHYDROGENASE FROM RHODOTORULA GRAMINIS WITH OTHER L-2-HYDROXYACID DEHYDROGENASE ENZYME AND ITS PRIMARY STRUCTURE PREDICTION
2001Co-Authors: Rosli Md. Illias, Graeme A. Reid, Nadzarah A. WahabAbstract:Abstract. A comparison of the primary structure for L-mandelate dehydrogenase (L-MDH) from Rhodotorula graminis with other proteins from the protein databank suggests that there is similarity between this protein and L-2-hydroxyacid dehydrogenase enzymes. R. graminis LMDH exhibits 26–42 % identity to L-Lactate dehydrogenase from Saccharomyces cerevisiae, L-Lactate dehy-drogenase from Hansenula anomala, glycolate oxidase from spinach, L-Lactate dehydrogenase from Escherichia coli, L-mandelate dehydrogenase from Pseudomonas putida and Lactate-2-Monooxygenase from Mycobacterium smegmatis. Structurally conserved amino acids are predicted from LMDH sequences corresponding to important regions of the cytochrome and FMN-binding domain de-fined from the known three-dimensional structure of the L-Lactate dehydrogenase from Saccharo-myces cerevisiae. Key words: L-MDH, Rhodotorula graminis, L-mandelate dehydrogenase, amino acid, flavocytochrome b2 Abstrak. Perbandingan struktur primer L(+)-mandalate dehydrogenase (L-MDH) daripada yis Rhodotorula graminis dengan protein lain di dalam bank data protein menunjukkan persamaan di antara protein ini dengan kumpulan enzim L-2-hidroksiasid dehidrogenase. LMDH daripada R
Rosli Md. Illias - One of the best experts on this subject based on the ideXlab platform.
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Comparison of the Amino Acid Sequence of L–Mandelate Dehydrogenase From Rhodotorula Graminis With Other L–2–Hydroxyacid Dehydrogenase Enzyme and its Primary Structure Prediction
Jurnal Teknologi, 2012Co-Authors: Rosli Md. Illias, Graeme A. Reid, Nadzarah A. WahabAbstract:Perbandingan struktur primer L(+)–mendalate dehydrogenase (L–MDH) daripada yis Rhodotorula graminis dengan protein lain di dalam bank data protein menunjukkan persamaan di antara protein ini dengan kumpulan enzim L–2–hidroksiasid dehidrogenase. LMDH daripada R. graminis mempamerkan kesamaan antara 26–42% kepada L–Lactate dehidrogenase daripada Sacchomoryces cerevisiae, L–Lactate dehidrogenase daripada Hansenula anomala, glikolat oksida daripada bayam, L–laktat dehidrogenase daripada Escherichia coli, LMDH daripada Psedomonas putida dan laktat–2 monooksigenase daripada Mycobakterium smegmatis. Asid amino yang penting secara strukturnya bagi LMDH diramalkan secara perbandingan dengan bahagian penting domain sitokram dan domain perlekatan FMN yang diperoleh daripada struktur tiga dimensi L–laktat dehidrogenase daripada Sacchoromyces cerevisiae. Kata kunci: L-MDH; Rhodotorula gramisis; L(+)-mandalate dehydrogenase; asid amino,flavocytochrome b2 A comparison of the primary structure or L–mandelate dehydrogenase (L–MDH) from Rhodotorula graminis with other proteins from the protein databank suggests that there is similarity between this protein and L–2–hydroxyacid dehydrogenase enzymes. R graminis LMDH exhibits 26–42% identity to L–Lactate dehydrogenase from Saccharomyces cerevisiae, L–Lactate dehydrogenase from Hansenula anomala, glycolate oxidase from spinach, L–Lactate dehydrogenase from Escherichia coli, L–mandelate dehydrogenase from Pseudomonas putida and Lactate–2–Monooxygenase from Mycobacterium smegmatis. Structurally conserved amino acids are predicted from LMDH sequences corresponding to important regions of the cytochrome and FMN–binding domain defined from the known three–dimensional structure of the L–Lactate dehyrogenase from Sacchoromyces cerevisiae. Key words: L-MDH; Rhodotorula graminis; L-mandelate dehydrogenase; amino acid;flavocytochrome b2
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COMPARISON OF THE AMINO ACID SEQUENCE OF L-MANDELATE DEHYDROGENASE FROM RHODOTORULA GRAMINIS WITH OTHER L-2-HYDROXYACID DEHYDROGENASE ENZYME AND ITS PRIMARY STRUCTURE PREDICTION
2001Co-Authors: Rosli Md. Illias, Graeme A. Reid, Nadzarah A. WahabAbstract:Abstract. A comparison of the primary structure for L-mandelate dehydrogenase (L-MDH) from Rhodotorula graminis with other proteins from the protein databank suggests that there is similarity between this protein and L-2-hydroxyacid dehydrogenase enzymes. R. graminis LMDH exhibits 26–42 % identity to L-Lactate dehydrogenase from Saccharomyces cerevisiae, L-Lactate dehy-drogenase from Hansenula anomala, glycolate oxidase from spinach, L-Lactate dehydrogenase from Escherichia coli, L-mandelate dehydrogenase from Pseudomonas putida and Lactate-2-Monooxygenase from Mycobacterium smegmatis. Structurally conserved amino acids are predicted from LMDH sequences corresponding to important regions of the cytochrome and FMN-binding domain de-fined from the known three-dimensional structure of the L-Lactate dehydrogenase from Saccharo-myces cerevisiae. Key words: L-MDH, Rhodotorula graminis, L-mandelate dehydrogenase, amino acid, flavocytochrome b2 Abstrak. Perbandingan struktur primer L(+)-mandalate dehydrogenase (L-MDH) daripada yis Rhodotorula graminis dengan protein lain di dalam bank data protein menunjukkan persamaan di antara protein ini dengan kumpulan enzim L-2-hidroksiasid dehidrogenase. LMDH daripada R
J. G. Schindler - One of the best experts on this subject based on the ideXlab platform.
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O2 sensitive L-Lactate biosensors with enzyme membranes based on L-Lactate-2-Monooxygenase and L-Lactate-oxidase with electroanalytic comparison
Biomedizinische Technik. Biomedical engineering, 1996Co-Authors: H. Guntermann, K. Herna, M. M. Schindler, J. G. SchindlerAbstract:O2-sensitive biosensors using oxidase membranes have acquired considerable electro-analytical importance. Since some of these O2-converting enzymes also produce H2O2, the use of additive reagents for the O2-free breakdown of the H2O2 in the second reaction has repeatedly been reported. In contrast to L-Lactate oxidase, L-Lactate-2-Monooxygenase converts its substrate without producing H2O2. Employing reference sera, tests with L-Lactate showed that bioelectrochemical membrane electrodes with H2O2-producing enzymes of high purity, require no additive reagents to ensure reliable analysis. Continuous measurements with citrated blood using the principle of intermediate carrier analysis are demonstrated.
Karel Ch. A. M. Luyben - One of the best experts on this subject based on the ideXlab platform.
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Comparison of two experimental methods for the determination of Michaelis-Menten kinetics of an immobilized enzyme.
Biotechnology and bioengineering, 1992Co-Authors: Christine M. Hooijmans, M. L. Stoop, M. Boon, Karel Ch. A. M. LuybenAbstract:For the application of immobilized enzymes, the influence of immobilization on the activity of the enzyme should be Known. This influence can be obtained by determining the intrinsic kinetic parameters of the immobilized enzyme, and by comparing them with the kinetic parameters of the suspended enzyme. This article deals with the determination of the intrinsic kinetic parameters of an agarose-gel bead immobilized oxygen-consuming enzyme: L-Lactate 2-Monooxygenase. The reaction rate of the enzyme can be described by Michaelis–Menten kinetics. Batch conversion experiments using a biological oxygen monitor, as well as steady-state profile measurements within the biocatalyst particles using an oxygen microsensor, were performed. Two different mathematical methods were used for the batch conversion experiments, both assuming a pseudosteady-state situation with respect to the shape of the profile inside the bead. One of the methods used an approximate relation for the effectiveness factor for Michaelis–Menten kinetics which interpolates between the analytical solutions for zero- and first-order kinetics. The other mathematical method was based on a numerical solution and combined a mass balance over the reactor with a mass balance over the bead. The main difference in the application of the two methods is the computer calculation time; the completely numerical calculation procedure was about 20 times slower than the other calculation procedure. The intrinsic kinetic parameters resulting from both experimental methods were compared to check the reliability of the methods. There was no significant difference in the intrinsic kinetic parameters obtained from the two experimental methods. By comparison of the kinetic parameters for the suspended enzyme with the intrinsic kinetic parameters for the immobilized enzyme, it appeared that immobilization caused a decrease in the value of Vm by a factor of 2, but there was no significant difference in the values obtained for Km.
Muh Ute - One of the best experts on this subject based on the ideXlab platform.
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Lactate oxidase: Expression of the gene in Escherichia coli and studies of the reaction mechanism through active site mutations.
1993Co-Authors: Muh UteAbstract:L-Lactate-2-Monooxygenase from Mycobacterium smegmatis catalyzes the reaction of L-Lactate with oxygen yielding acetate, carbon dioxide and water. The gene for Lactate oxidase was expressed in E. coli under control of the T 7 polymerase promoter. Based on the homology of Lactate oxidase with the amino acid sequence of two related enzymes, flavocytochrome b$\sb2$ and glycolate oxidase, for which crystal structures are known, several amino acid residues were postulated to participate in catalysis. Tyrosine 44 and arginine 293 are assumed to stabilize the binding of Lactate and were replaced by phenylalanine and lysine residues, respectively. Tyrosine 152 is assumed to participate in the binding of substrate and in the stabilization of a reaction intermediate and was mutated to phenylalanine. Histidine 290 was postulated to initiate catalysis by abstraction of a proton from the substrate and was replaced with glutamine. Lysine 266 may be in the appropriate position relative to the flavin-N(1) to stabilize a negatively charged hydroquinone during turnover. It was mutated to a methionine. All of the substitutions at the active site resulted in reduced catalytic efficiency. It appears that the main effect is on the ability of the enzymes to stabilize the transition state. In H290Q the capacity to generate the transient substrate carbanion has presumably been removed and the enzyme is essentially inactive. R293K, Y44F and Y152F bind Lactate as well as the wild type enzyme, but show a substantially higher dissociation constant for the transition state analog oxalate. A linear relationship exists between the rate of reduction and the capacity to bind oxalate. For K266M it could be shown that the properties of Lactate oxidase which had led to the initial postulation of a positively charged amino acid residue, such as tight binding of sulfite and the stabilization of an anionic semiquinone, were affected. In contrast to the wild type enzyme, binding of sulfite was about 17 000 fold weaker, and the semiquinone was no longer thermodynamically stable.Ph.D.Biological ChemistryUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/103460/1/9319595.pdfDescription of 9319595.pdf : Restricted to UM users only
