The gene encoding RUM630-BX, a β-xylosidase/arabinofuranosidase, was identified from activity-based screening of a cow rumen metagenomic library. The recombinant enzyme is activated as much as 14-fold (kcat) by divalent metals Mg(2+), Mn(2+) and Co(2+) but not by Ca(2+), Ni(2+), and Zn(2+). Activation of RUM630-BX by Mg(2+) (t0.5 144 s) is slowed two-fold by prior incubation with substrate, consistent with the X-ray structure of closely related xylosidase RS223-BX that shows the divalent-metal activator is at the back of the active-site pocket so that bound substrate could block its entrance. The enzyme is considerably more active on natural substrates than artificial substrates, with activity (kcat/Km) of 299 s(-1) mM(-1) on xylotetraose being the highest reported.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.enzmictec.2015.10.001 | DOI Listing |
Nutrients
September 2024
Department of Animal Food Resources, College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea.
In recent years, alongside research on mammalian-derived exosomes, there has been increasing interest in the physiological activities of plant-derived exosome-like nanoparticles (PDEN). The biocompatibility, minimal side effects, and diverse bioactive ingredients contained in PDEN make them valuable as potential therapeutic agents for an extensive range of diseases. In this study, we cost-effectively isolated exosome-like nanoparticles from green onion (Allium fistulosum) using polyethylene glycol and examined their biological activity in HT-22 cells exposed to glutamate.
View Article and Find Full Text PDFJ Neuroinflammation
September 2024
Department of Molecular Physiology and Biophysics, Vanderbilt University, 702 Light Hall, Nashville, TN, USA.
Background: Microglial cell iron load and inflammatory activation are significant hallmarks of late-stage Alzheimer's disease (AD). In vitro, microglia preferentially upregulate the iron importer, divalent metal transporter 1 (DMT1, gene name Slc11a2) in response to inflammatory stimuli, and excess iron can augment cellular inflammation, suggesting a feed-forward loop between iron import mechanisms and inflammatory signaling. However, it is not understood whether microglial iron import mechanisms directly contribute to inflammatory signaling and chronic disease in vivo.
View Article and Find Full Text PDFProtein Expr Purif
November 2024
SJTU Yazhou Bay Institute of Deepsea Sci-Tech, Yongyou Industrial Park, Sanya, 572024, China; State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dong-Chuan Road, Shanghai, 200240, China; Joint International Research Laboratory of Metabolic & Developmental Sciences (Ministry of Education), Shanghai Jiao Tong University, 800 Dong-Chuan Road, Shanghai, 200240, China. Electronic address:
Nucleases play pivotal roles in DNA repair and apoptosis. Moreover, they have various applications in biotechnology and industry. Among nucleases, TatD has been characterized as an exonuclease with various biological functions in different organisms.
View Article and Find Full Text PDFBackground: Microglial cell iron load and inflammatory activation are significant hallmarks of late-stage Alzheimer's disease (AD). , microglia preferentially upregulate the iron importer, divalent metal transporter 1 (DMT1, gene name ) in response to inflammatory stimuli, and excess iron can augment cellular inflammation, suggesting a feed-forward loop between iron import mechanisms and inflammatory signaling. However, it is not understood whether microglial iron import mechanisms directly contribute to inflammatory signaling and chronic disease .
View Article and Find Full Text PDFFood Res Int
August 2024
Anhui Engineering Laboratory for Agro-products Processing, Anhui Agricultural University, Hefei 230036, China; Anhui Engineering Research Center of Functional Food for Plant Active Peptides, Hefei 230036, Anhui, China; Department of Food Science and Engineering, College of Tea and Food Science & Technology, Anhui Agricultural University, Hefei 230036, Anhui, China; Key Laboratory of Jianghuai Agricultural Product Fine Processing and Resource Utilization, Ministry of Agriculture and Rural Affairs, Anhui Engineering Research Center for High Value Utilization of Characteristic Agricultural Products, College of Tea & Food Science and Technology, Anhui Agricultural University, Hefei, China. Electronic address:
There is an increasing amount of research into the development of a third generation of iron supplementation using peptide-iron chelates. Peptides isolated from mung bean were chelated with ferrous iron (MBP-Fe) and tested as a supplement in mice suffering from iron-deficiency anemia (IDA). Mice were randomly divided into seven groups: a group fed the normal diet, the IDA model group, and IDA groups treated with inorganic iron (FeSO), organic iron (ferrous bisglycinate, Gly-Fe), low-dose MBP-Fe(L-MBP-Fe), high-dose MBP-Fe(H-MBP-Fe), and MBP mixed with FeSO (MBP/Fe).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!