Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.

| S-EPMC2531291 | biostudies-literature

Homo sapiens

Project description:Structural genomic variation analysis in patients with bone marrow failure using Illumina Infinium SNP Arrays [Illumina Quad610 Beadchip]

| PRJNA210312 | ENA

Structural genomic variation analysis in patients with bone marrow failure using Illumina Infinium SNP Arrays [Omni1-Quad]

Project description:To better understand the natural history of bone marrow failure syndromes, we analyzed 124 single nucleotide polymorphism arrays (SNP-A) from a comprehensively characterized cohort of 91 patients who had SNP-A for clinical evaluation of BMFS. 67 samples from 51 patients were genotyped with the Quad610, and 57 samples from 54 patients were genotyped with the Omni1-Quad. This submission includes 55 samples from 54 patients that were genotyped with Omni1-Quad. Illumina Infinium SNP-A genotyping was performed on DNA extracted from bone marrow aspirates using standard manufacturer's protocol

2014-01-01 | E-GEOD-48482 | biostudies-arrayexpress

Structural genomic variation analysis in patients with bone marrow failure using Illumina Infinium SNP Arrays [Illumina Quad610 Beadchip]

Project description:To better understand the natural history of bone marrow failure syndromes, we analyzed 124 single nucleotide polymorphism arrays (SNP-A) from a comprehensively characterized cohort of 91 patients who had SNP-A for clinical evaluation of BMFS. 67 samples from 51 patients were genotyped with the Quad610, and 57 samples from 54 patients were genotyped with the Omni1-Quad. This submission includes 67 samples from 51 patients that were genotyped with Illumina Quad610 Beadchip. Illumina Infinium SNP-A genotyping was performed on DNA extracted from bone marrow aspirates using standard manufacturer's protocol

2014-01-01 | E-GEOD-48483 | biostudies-arrayexpress

Homo sapiens whole blood.

Project description:RNA extracted at 240min. Samples are rRNA depleted. Expression measurement of Homo sapiens genes.

2019-07-31 | GSE114179 | GEO