The acrosin zymogen proacrosin exists in two molecular forms which are believed to be single-chain polypeptides. During autoactivation in a cell-free system, the 55 and 53 kDa zymogens are sequentially converted into the 49, 36, 31 and 25 kDa forms. A similar mechanism of maturation was revealed, when the calcium ionophore A23187 was added to suspensions of boar spermatozoa. The 49 kDa form has been identified as the first active acrosin form in the maturation cascade. However, this form is indistinguishable from the 53 kDa zymogen in SDS-PAGE at nonreducing conditions. Two carbohydrate chains were evidenced on the acrosin molecule. The chain attached to the Asn3 of the acrosin light chain was enzymatically cleaved without loss of acrosin activity. By contrast, the carbohydrate chain linked to the acrosin heavy chain could be cleaved only after acrosin denaturation. Based on the susceptibility of acrosin to endoglycosidases F and H, a biantennary structure of both carbohydrate chains is proposed.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/0014-5793(91)81335-6 | DOI Listing |
Commun Biol
January 2025
Department of Chemistry, University of Warwick, Coventry, UK.
Pectin is a major component of plant cells walls. The extent to which pectin chains crosslink with one another determines crucial properties including cell wall strength, porosity, and the ability of small, biologically significant molecules to access the cell. Despite its importance, significant gaps remain in our comprehension, at the molecular level, of how pectin cross-links influence the mechanical and physical properties of cell walls.
View Article and Find Full Text PDFHLA
January 2025
HLA and Histocompatibility Laboratory, CHRU de Nancy, Vandœuvre-lès-Nancy, France.
The novel allele HLA-DPB1*1617:01 differs from HLA-DPB1*05:01:01:01 by one non-synonymous nucleotide substitution in exon 2.
View Article and Find Full Text PDFNeuromolecular Med
January 2025
Pharmacy College, Al-Farahidi University, Baghdad, Iraq.
The primary source of short-chain fatty acids (SCFAs), now recognized as critical mediators of host health, particularly in the context of neurobiology and cancer development, is the gut microbiota's fermentation of dietary fibers. Recent research highlights the complex influence of SCFAs, such as acetate, propionate, and butyrate, on brain cancer progression. These SCFAs impact immune modulation and the tumor microenvironment, particularly in brain tumors like glioma.
View Article and Find Full Text PDFMol Med Rep
March 2025
Collaborative Innovation Center of Research and Development on the Whole Industry Chain of Yu‑Yao, Henan Province, Henan University of Chinese Medicine, Zhengzhou, Henan 450046, P.R. China.
Calycosin‑7‑O‑β‑D‑glucoside (CG), a major active ingredient of Astragali Radix, exerts neuroprotective effects against cerebral ischemia; however, whether the effects of CG are associated with mitochondrial protection remains unclear. The present study explored the role of CG in improving mitochondrial function in a HT22 cell model of oxygen‑glucose deprivation/reperfusion (OGD/R). The Cell Counting Kit‑8 assay, flow cytometry, immunofluorescence and western blotting were performed to investigate the effects of CG on mitochondrial function.
View Article and Find Full Text PDFCommun Biol
January 2025
Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan.
Galactosides are major carbohydrates that are found in plant cell walls and various prebiotic oligosaccharides. Studying the detailed biochemical functions of β-galactosidases in degrading these carbohydrates is important. In particular, identifying β-galactosidases with new substrate specificities could help in the production of potentially beneficial oligosaccharides.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!