Project description:Collaborative Cohort of Cohorts for COVID-19 Research (C4R): Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS)
Project description:Collaborative Cohort of Cohorts for COVID-19 Research (C4R): Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS)
Project description:Plasma Metabolomic signatures of COPD in a SPIROMICS cohort The Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) (ClinicalTrials.gov Identifier: NCT01969344) includes 2,771 subjects, aged 40-80 years with at least 20 pack-years of smoking. An additional 202 subjects were never smokers. Fasting blood drawn at the enrollment visit using a p100 tube. The first 648 subjects who returned for a 5-7 year visit (Visit 5) were selected for this study. The blood profiled were from the year 1 visit. This study is a duplicate of ST001639 (https://www.metabolomicsworkbench.org/data/DRCCMetadata.php?Mode=Study&StudyID=ST001639) but differs in analysis and contains batch normalized data using median metabolite values.
Project description:The Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) (ClinicalTrials.gov Identifier: NCT01969344) includes 2,771 subjects, aged 40-80 years with at least 20 pack-years of smoking. An additional 202 subjects were never smokers. Fasting blood drawn at the enrollment visit using a p100 tube. The first 649 subjects who returned for a 5-7 year visit (Visit 5) were selected for this study. The blood profiled were from the year 1 visit.
Project description:Differential profiles from whole genome human expression arrays on monocytes obtained from peripheral blood in COPD was studied and compared with controls. Monocytes were isolated from Controls (Group 1) which included Control Smokers (Group 1A) and Control Never Smokers (Group 1B) and COPD (Group 2) which included COPD Smokers (Group 2A) and COPD ExSmokers (Group 2B). Differential transcriptomic expression associated with (i) Smoking, (ii) COPD, and (iii) cessation of smoking were identified.
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.
