Post-translational hydroxylation of the L-proline residue mainly occurs in collagen; therefore, the L-hydroxyprolines (L-Hyp) synthesized, including trans-4-hydroxy-L-proline (T4LHyp) and trans-3-hydroxy-L-proline (T3LHyp), are important markers for directly measuring the content of collagen in several biological samples. The most frequently used method to estimate the content of L-Hyp is high-performance liquid chromatography (HPLC), which is inconvenient. In the present study, we attempted to estimate the content of L-Hyp using coupling systems with metabolic enzymes of the T4LHyp (hydroxyproline 2-epimerase (HypE) and cis-4-hydroxy-D-proline dehydrogenase (HypDH)) and T3LHyp pathways (T3LHyp dehydratase (T3LHypD) and Δ(1)-pyrroline-2-carboxylate reductase (Pyr2CR)) from microorganisms. We constructed a functional expression system of recombinant HypDH with a heterooligomeric structure in Escherichia coli cells. Enzymological characterization revealed that the β-subunit acted as a catalytic subunit, and also that assembly with other subunit(s) improved the kinetics for cis-4-hydroxy-D-proline and thermostability. By using a spectrophotometric assay with different wavelengths, the contents of T4LHyp and T3LHyp were successfully estimated within the ranges of 0.004-1mM and 0.05-1mM, respectively, and were consistent with those determined by HPLC. This enzymatic method was used to measure the content of T4LHyp in the acid-hydrolysate of collagen, and blood plasma.
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http://dx.doi.org/10.1016/j.jbiotec.2015.01.026 | DOI Listing |
J Equine Vet Sci
January 2025
School of Animal Sciences, Virginia Polytechnic Institute and State University, 175 West Campus Dr., Blacksburg, VA, USA, 24061. Electronic address:
Our objectives were to use a quantitative literature review to explore dietary and feed factors influencing apparent total-tract digestibility of dry matter (DMD), crude protein (CPD), neutral detergent fiber (NDFD), ether extract (EED), non-structural carbohydrates (NSCD), non-fiber carbohydrates (NFCD), and residual organic matter (rOMD) in equine diets, and to assess their contributions to digestible energy (DE) supplies. Data from 54 studies were modeled using linear mixed-effect regressions, with publication as a random effect to account for study variability. For each nutrient, five models were derived with explanatory variables including: dry matter intake (DMI; % BW/day) and DM (% as-fed), and dietary components (CP, organic matter, EE, NDF, acid detergent fiber, NSC, starch, and NFC as % of DM), and feed types (forage, non-forage fiber, legumes, cereal, and oil proportions).
View Article and Find Full Text PDFThromb Res
January 2025
Thrombosis Research Group, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; YNHH/Yale Center for Outcomes Research and Evaluation (CORE), New Haven, CT, USA; Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. Electronic address:
Background: Isolated subsegmental pulmonary embolism (issPE) is a commonly encountered diagnosis. Although the International Classification of Diseases (ICD)-10 codes are used for research, their validity for identifying issPE is unknown. Moreover, issPE diagnosis is challenging, and the findings from radiology reports may conflict with those from expert radiologists.
View Article and Find Full Text PDFChemosphere
January 2025
Chemical and Veterinary Analytical Institute Muensterland-Emscher-Lippe, Joseph-König-Str. 40, 48147, Muenster, Germany.
Perfluorocarboxylic acids and perfluorosulfonic acids accumulate in food webs, thus posing a serious threat to food safety. The European Food Safety Authority (EFSA) derived a tolerable weekly intake (TWI) of 4.4 ng/kg body weight for the sum of the four so-called EFSA-PFAS in 2020.
View Article and Find Full Text PDFSci Total Environ
January 2025
Geology and Sustainable Mining Institute, Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco.
In the face of the climate change crisis, circular economy (CE) is put forward as a promising key to the sustainable development goals (SDGs) riddle. In this context that affects developed and developing countries alike, circular initiatives arise, such is the case for Morocco where an industrial synergy based on the CE concept of 'waste is food' can be envisioned between the local phosphate and cement industries. In order to support and guide this initiative, a life cycle assessment (LCA) was conducted to compare the environmental performance of the production of ordinary Portland cement (OPC), limestone calcined clay cement (LC3) and a phosphate waste-based cement known as calcined marl cement (CMC).
View Article and Find Full Text PDFJ Bone Miner Res
January 2025
MRC Lifecourse Epidemiology Centre, Human Development and Health, University of Southampton, Southampton, United Kingdom.
HIV-related mortality has fallen due to scale-up of antiretroviral therapy (ART), so more women living with HIV (WLH) now live to reach menopause. Menopausal estrogen loss causes bone loss, as do HIV and certain ART regimens. However, quantitative bone data from WLH are few in Africa.
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