Assignment of Endogenous Substrates to Enzymes by Global Metabolite Profiling
摘要:
Enzymes regulate biological processes through the conversion of specific substrates to products. Therefore, of fundamental interest for every enzyme is the elucidation of its natural substrates. Here, we describe a general strategy for identifying endogenous substrates of enzymes by untargeted liquid chromatography-mass spectrometry (LC-MS) analysis of tissue metabolomes from wild-type and enzyme-inactivated organisms. We use this method to discover several brain lipids regulated by the mammalian enzyme fatty acid amide hydrolase (FAAH) in vivo, including known signaling molecules (e.g., the endogenous cannabinoid anandamide) and a novel family of nervous system-enriched natural products, the taurine-conjugated fatty acids. Remarkably, the relative hydrolytic activity that FAAH exhibited for lipid metabolites in vitro was not predictive of the identity of specific FAAH substrates in vivo. Thus, global metabolite profiling establishes unanticipated connections between the proteome and metabolome that enable assignment of an enzyme's unique biochemical functions in vivo.
A photothermographic material comprising a support, and an image-forming layer and a non-photosensitive layer provided on a surface of the support, wherein the image-forming layer and the non-photosensitive layer are adjacent to each other; the image-forming layer includes a photosensitive silver halide, a first non-photosensitive organic silver salt, a first reducing agent, a polyhalogen compound and a binder; and the non-photosensitive layer includes a second non-photosensitive organic silver salt.
The Human Bile Acid-CoA:Amino Acid N-Acyltransferase Functions in the Conjugation of Fatty Acids to Glycine
作者:James O'Byrne、Mary C. Hunt、Dilip K. Rai、Masayumi Saeki、Stefan E.H. Alexson
DOI:10.1074/jbc.m300987200
日期:2003.9
Bile acid-CoA:aminoacidN-acyltransferase (BACAT) catalyzes the conjugation of bile acids to glycine and taurine for excretion into bile. By use of site-directed mutagenesis and sequence comparisons, we have identified Cys-235, Asp-328, and His-362 as constituting a catalytic triad in human BACAT (hBACAT) and identifying BACAT as a member of the type I acyl-CoA thioesterase gene family. We therefore
Biosynthesis of Cell Envelope-Associated Phenolic Glycolipids in Mycobacterium marinum
作者:Olivia Vergnolle、Sivagami Sundaram Chavadi、Uthamaphani R. Edupuganti、Poornima Mohandas、Catherine Chan、Julie Zeng、Mykhailo Kopylov、Nicholas G. Angelo、J. David Warren、Clifford E. Soll、Luis E. N. Quadri
DOI:10.1128/jb.02546-14
日期:2015.3.15
acyl-AMP ligase (FadD26) for biosynthesis of phthiocerol dimycocerosates (PDIMs), which are nonglycosylated lipids structurally related to PGLs. To our knowledge, the partially overlapping PGL and PDIM biosynthetic pathways provide the first example of two distinct, pathway-dedicated acyl-AMP ligases loading the same type I polyketide synthase system with two alternatestarterunits to produce two structurally
Molecular Cloning and Characterization of Two Mouse Peroxisome Proliferator-activated Receptor α (PPARα)-regulated Peroxisomal Acyl-CoA Thioesterases
作者:Maria A.K. Westin、Stefan E.H. Alexson、Mary C. Hunt
DOI:10.1074/jbc.m313863200
日期:2004.5
long- and very long-chainacyl-CoAs, bile acid-CoA intermediates, prostaglandins, leukotrienes, thromboxanes, dicarboxylic fatty acids, pristanic acid, and xenobiotic carboxylic acids. The very long- and long-chainacyl-CoAs are mainly chain-shortened and then transported to mitochondria for further metabolism. We have now identified and characterized two peroxisomalacyl-CoAthioesterases, named PTE-Ia
Gene Knockout Reveals a Novel Gene Cluster for the Synthesis of a Class of Cell Wall Lipids Unique to Pathogenic Mycobacteria
作者:Abul K. Azad、Tatiana D. Sirakova、Norvin D. Fernandes、Pappachan E. Kolattukudy
DOI:10.1074/jbc.272.27.16741
日期:1997.7
biosynthesis of phthiocerol and phenolphthiocerol. A cosmid containing the postulated pps gene cluster was identified by screening a genomic library of Mycobacterium bovis BCG with the postulated homologous domains from mycocerosic acid synthase and fatty acid synthase genes as probes. Homologous cosmids were also identified in the genomic libraries of Mycobacterium tuberculosis and Mycobacterium leprae. M