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- González-Domínguez, Álvaro, et al.
(författare)
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Untargeted Metabolomics Based on Liquid Chromatography-Mass Spectrometry for the Analysis of Plasma and Erythrocyte Samples in Childhood Obesity
- 2023
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Ingår i: Methods in Molecular Biology. - New York, NY : Springer US. - 1940-6029 .- 1064-3745. ; , s. 115-122
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The circulating metabolome of human peripheral blood provides valuable information to investigate the molecular mechanisms underlying the development of diseases and to discover candidate biomarkers. In particular, erythrocytes have been proposed as potential systemic indicators of the metabolic and redox status of the organism. To accomplish wide-coverage metabolomics analysis, the combination of complementary analytical techniques is necessary to manage the physicochemical complexity of the human metabolome. Herein, we describe an untargeted metabolomics method to capture the plasmatic and erythroid metabolomes based on ultrahigh-performance liquid chromatography coupled to high-resolution mass spectrometry, combining reversed-phase liquid chromatography and hydrophilic interaction liquid chromatography. The method provides comprehensive metabolomics fingerprinting of plasma and erythrocyte samples, thereby enabling the elucidation of the distinctive metabolic disturbances behind childhood obesity and associated comorbidities, such as insulin resistance.
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| 2. |
- Kmezik, Cathleen, 1991, et al.
(författare)
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A polysaccharide utilization locus from the gut bacterium Dysgonomonas mossii encodes functionally distinct carbohydrate esterases.
- 2021
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Ingår i: The Journal of biological chemistry. - : Elsevier BV. - 1083-351X .- 0021-9258. ; 296
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Tidskriftsartikel (refereegranskat)abstract
- The gut microbiota plays a central role in human health by enzymatically degrading dietary fiber and concomitantly excreting short chain fatty acids that are associated with manifold health benefits. The polysaccharide xylan is abundant in dietary fiber but non-carbohydrate decorations hinder efficient cleavage by glycoside hydrolases (GHs) and need to be addressed by carbohydrate esterases (CEs). Enzymes from carbohydrate esterase families 1 and 6 (CE1 & 6) perform key roles in xylan degradation by removing feruloyl and acetate decorations, yet little is known about these enzyme families especially with regards to their diversity in activity. Bacteroidetes bacteria are dominant members of the microbiota and often encode their carbohydrate-active enzymes in multi-gene polysaccharide utilization loci (PULs). Here we present the characterization of three CEs found in a PUL encoded by the gut Bacteroidete Dysgonomonas mossii. We demonstrate that the CEs are functionally distinct, with one highly efficient CE6 acetyl esterase and two CE1 enzymes with feruloyl esterase activities. One multidomain CE1 enzyme contains two CE1 domains: an N-terminal domain feruloyl esterase, and a C-terminal domain with minimal activity on model substrates. We present the structure of the C-terminal CE1 domain with the carbohydrate binding module that bridges the two CE1 domains, as well as a complex of the same protein fragment with methyl ferulate. The investment of D. mossii in producing multiple CEs suggests that improved accessibility of xylan for GHs as well as cleavage of covalent polysaccharide-polysaccharide and lignin-polysaccharide bonds are important enzyme activities in the gut environment.
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