β-estradiol (β-E2) and α-estradiol (α-E2) act as an endo- and an exon-estrogen in humans, respectively. There is a structural variation in C17-OH configuration of the two estrogens. UDP-glucuronosyltransferases (UGT) are responsible for termination of activities of a variety of endogenous hormones, clinical drugs, and environmental toxicants. The current study was conducted to investigate the effects of the two estrogens towards catalytic activities of UGTs. It was found that β-E2 could decrease activities of UGT1A9, - 2B4 and - 2B7, with K values of a few micro-molars. β-E2 could additionally accelerate the activity of UGT2B17 via promoting enzyme-substrate binding and increasing the turn over number. Comparatively, α-E2 displayed much stronger inhibitory potentials towards UGT2B7 and - 2B4, but showed little influence to UGT1A9 and - 2B17. The K values for inhibition of UGT2B7 in glucuronidation of different substrates by α-E2 were in a nanomolar range that is only about 1/100-1/50 of β-E2. UGT2B7 structural model was fatherly constructed to explore the mechanism underlying dramatically different inhibition selectivity of the two estrogens. Compared to β-E2, α-E2 formed more hydrophobic and hydrogen-bonded interactions with the residues in the active pocket. It is concluded that the configuration of E2-17-OH determines the inhibitory potentials towards UGTs. The results are useful in better understanding ligand selectivity of UGTs, as well as in further development of α-E2 in health protection.
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http://dx.doi.org/10.1016/j.jsbmb.2022.106196 | DOI Listing |
Blood Adv
January 2025
Vanderbilt University Medical Center, Nashville, Tennessee, United States.
In plasma, the zymogens factor XII (FXII) and prekallikrein reciprocally convert each other to the proteases FXIIa and plasma kallikrein (PKa). PKa cleaves high-molecular-weight kininogen (HK) to release bradykinin, which contributes to regulation of blood vessel tone and permeability. Plasma FXII is normally in a "closed" conformation that limits activation by PKa.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Selective catalytic reduction of NO by NH(NH-SCR) remains challenging for diesel vehicles due to the complex exhaust condition. Cu-SAPO-18 zeolite has emerged as an efficient catalyst for the NH-SCR process, attributed to its unique small pore configuration and high NH-SCR activity. Herein, Zr-modified Cu-SAPO-18 has been fabricated and evaluated for the reduction of NO.
View Article and Find Full Text PDFScience
January 2025
Redox and Metalloprotein Research Group, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
In the ancient microbial Wood-Ljungdahl pathway, carbon dioxide (CO) is fixed in a multistep process that ends with acetyl-coenzyme A (acetyl-CoA) synthesis at the bifunctional carbon monoxide dehydrogenase/acetyl-CoA synthase complex (CODH/ACS). In this work, we present structural snapshots of the CODH/ACS from the gas-converting acetogen , characterizing the molecular choreography of the overall reaction, including electron transfer to the CODH for CO reduction, methyl transfer from the corrinoid iron-sulfur protein (CoFeSP) partner to the ACS active site, and acetyl-CoA production. Unlike CODH, the multidomain ACS undergoes large conformational changes to form an internal connection to the CODH active site, accommodate the CoFeSP for methyl transfer, and protect the reaction intermediates.
View Article and Find Full Text PDFBiochemistry
January 2025
School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, United Kingdom.
The enzyme 4-oxo-l-proline reductase (BDH2) has recently been identified in humans. BDH2, previously thought to be a cytosolic ()-3-hydroxybutyrate dehydrogenase, actually catalyzes the NADH-dependent reduction of 4-oxo-l-proline to -4-hydroxy-l-proline, a compound with known anticancer activity. Here we provide an initial mechanistic characterization of the BDH2-catalyzed reaction.
View Article and Find Full Text PDFNat Prod Res
January 2025
Laboratory of Natural Products and Heterocyclic Synthesis, Department of Organic Chemistry, Faculty of Sciences, The University of Yaoundé 1, Yaoundé, Cameroon.
From the leaves of , fourteen compounds were isolated and identified: D-mannitol (), a mixture of β-sitosterol () and stigmasterol (), α-amyrin (), betulin (), lupeol (), lupenone (), betulinic acid (), taraxerol (), 3β-(E)-coumaroyltaraxerol (), 3β-(Z)-coumaroyltaraxerol (), ursolic acid (), stigmasterol 3-O-β-D-glucoside (), and β-sitosterol 3-O-β-D-glucoside (). These compounds were analysed through NMR spectroscopy (both 1D and 2D) and by comparing them to previously published data. Compounds , , , and - have been identified from this species for the first time.
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