The proteasome is a high molecular weight, multisubunit and multicatalytic enzyme. Here we report the purification and characterization of ostrich skeletal muscle 20S proteasome. It was purified to homogeneity with Mr 700,000, pI 6.67 and a 'ladder' of 22.2-33.5 kDa bands on SDS-PAGE. The amino acid composition and amino-terminal sequences showed large identities to those of other species. For the three major activities, pH and temperature optima ranged between 8.0-11.0 and 40-70 degrees C, and stabilities between 5-12 and up to 40-60 degrees C. Substrate specificity and inhibitory effects were also studied. Many similarities to other sources were shown, with a few significant differences.
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http://dx.doi.org/10.1515/BC.2002.141 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Xiamen University, Department of Chemistry, CHINA.
A pyrrole-fused analogue of warped nanographene, designated as deca-nitrogen doped 'WNG' (azaWNG), was synthesized through the annular fusion of decapyrroylcorannulene. The resulting azaWNG exhibited extremely limited solubility in common organic solvents and was characterized solely by mass spectrometry. Theoretical calculations revealed that azaWNG has a sunflower-like molecular structure with electron-deficient corannulene as the core and electron-rich pyrrole as the petals, demonstrating a significantly narrower energy gap compared to all-carbon WNG.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
School of Basic Medical Sciences, Kunming Medical University, Kunming 650500, Yunnan, China. Electronic address:
Most Kunitz inhibitors exhibit serine protease inhibitory activity, but limited information is available on the regulation of platelet function. Herein, we report the purification and characterization of a novel single Kunitz domain inhibitor (Sibanin) from the salivary glands of the black fly Simulium bannaense. Recombinant Sibanin prolonged activated partial thromboplastin time and prothrombin time, and exhibited high-affinity binding to FXa and elastase with a KD of 5.
View Article and Find Full Text PDFPlanta
January 2025
Institute of Plant Genetics and Biotechnology, Plant Science and Biodiversity Center, Slovak Academy of Sciences, Akademicka 2, P. O. Box 39A, 950 07, Nitra, Slovak Republic.
DbChitI-3, Drosera binata's acidic chitinase, peaks at pH 2.5 from 15 °C to 30 °C. Gene expression is stimulated by polysaccharides and suppressed by monosaccharide digestion, implying a feedback loop in its transcriptional regulation.
View Article and Find Full Text PDFCell Mol Biol (Noisy-le-grand)
January 2025
Plant Protection Department, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia.
Forty-four samples of garlic plants showing virus-like symptoms were collected, during the growing season (2021-2022) from different locations in Qassim province, Saudi Arabia. These samples were analyzed by ELISA against the important Allium allexiviruses including garlic virus A (GarV-A), garlic virus B (GarV-B), garlic virus C (GarV-C), and Shallot virus X (ShVX). The obtained results showed that 22/44 (50%) samples were found to be infected with one of the tested viruses.
View Article and Find Full Text PDFCell Mol Biol (Noisy-le-grand)
January 2025
Department Medical Laboratory Technology, College of Medical Technology, University of Al-Farahidi, Baghdad, Iraq.
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