The inhibition of Helix pomatia arylsulfatase by the synergistic combination of N-acetyl-l-tyrosine ethyl ester and vanadate has been extended to affinity chromatography for purification. In the presence of vanadate, l-tyrosine ethyl ester (TEE), immobilized on CH-Sepharose 4B retained arylsulfatase from the digestive juice or lyophilized powder of H. pomatia. No enzyme was retained without vanadate or with arsenate or phosphate. Arylsulfatase was eluted from the column matrix by removing the vanadate to less than 50 microM with buffer containing EDTA to chelate the vanadate. Escherichia coli alkaline phosphatase and potato acid phosphatase, two enzymes which are inhibited by vanadate but not by the vanadate-TEE complex, were not retained by the immobilized TEE under any conditions used. The sulfatase activity was completely separated from contaminating glucuronidase activity present in the crude enzyme extracts. The Ki for the immobilized vanadate-TEE system was found to be 5.0 x 10(-7) M with a capacity of 25 mg/ml swollen gel. A purification of greater than 40-fold from the lyophilized powder of H. pomatia (Sigma Type H-5) was achieved using this technique. The Ki/Keq of other phenols with vanadate were determined in a 96-well plate format as an example of a rapid screening technique that could be extended to other phosphoryl and sulfuryl-transfer enzyme classes.
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http://dx.doi.org/10.1006/prep.1998.1006 | DOI Listing |
Burns Trauma
March 2025
Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, No. 6 West Xuefu Road, Xinpu New District, Zunyi 563006, China.
Background: Diabetic wounds pose significant clinical challenges due to impaired healing processes, often resulting in chronic, nonhealing ulcers. Asiaticoside (AC), a natural triterpene derivative from , has demonstrated notable anti-inflammatory and wound-healing properties. However, the synergistic effects of nitric oxide (NO)-a recognized promoter of wound healing-combined with AC in treating diabetic wounds remain inadequately explored.
View Article and Find Full Text PDFChem Biodivers
March 2025
Jiangxi University of Traditional Chinese Medicine, Research Center of Natural Resources of Chinese Medicinal Materials and Ethnic Medicine, 1688 Meiling Road, 330004, Nanchang, CHINA.
Cyclooxygenase-2 (COX-2) plays a critical role in the pathogenesis of rheumatoid arthritis (RA), while Dendropanax dentiger root (DDR) is a traditional Chinese medicine (TCM) used to treat RA. However, the specific bioactive ingredients responsible for its therapeutic effect remain unidentified. In this study, 10 phenylpropanoids, including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, liriodendrin, isochlorogenic acid B, isochlorogenic acid A, eleutheroside E1, isochlorogenic acid C, 3,5-di-O-caffeoylquinic acid methyl ester, and 4,5-di-O-caffeoylquinic acid methyl ester, were identified as potential COX-2 inhibitors in DDR using affinity ultrafiltration coupled with ultra-high-performance liquid chromatography and mass spectrometry (AUF-LC-MS).
View Article and Find Full Text PDFJ Ethnopharmacol
March 2025
College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China. Electronic address:
Ethnopharmacological Relevance: Astragalus membranaceus, commonly known as Huangqi in China, is a traditional herbal medicine that has attracted significant attention for its immunomodulatory effects. It has been widely studied in various clinical contexts, including cancer treatment. Astragalus injection (HQI) is clinically used for treating myocarditis and cardiac insufficiency.
View Article and Find Full Text PDFBiochem Genet
March 2025
Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Caspase-9 is crucial for initiating apoptosis, and its activity is tightly regulated through various mechanisms, especially phosphorylation by kinases activated by extracellular growth factors, osmotic stress, or during mitosis. Mass spectrometric analyses have shown that residues S302 and S307 in human caspase-9 are prone to phosphorylation. To investigate the effects of phosphorylation at these sites, three phosphomimetic variants of recombinant caspase-9 were created: S302D, S307D, and the combined S302D/S307D variant.
View Article and Find Full Text PDFNon-ionic detergents enable the investigation of cell membranes, including biomolecule purification and drug delivery. The question of whether non-ionic detergents associated with satisfying protein yields following extraction and affinity purification of proteins from lysed E. coli membranes can amplify antibiotics on whole-cell E.
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