Four fragments (F1-F4) of SEA, obtained via papain proteolysis were separated and isolated as individual components by means of the SDS-electrophoresis in polyacrilamide gel. Molecular masses of the pairs F1 + F4 and F2 + F3 are equal to the mass of the intact toxin--a fact that supposes a cleavage of polypeptide chain in two regions of "disulphide loop" in a SEA molecule. Neither fragment possesses any enterpathogenic properties. It was established, that interferonogenic and mitogenic activity of SEA is connected only with the part of molecule corresponding to F1(17,500) and F3(15,000). Two kinds of antigenic determinants in the SEA molecule were found: one was attributed to F1 and F3 fragments, the other was localised in F2 and F4. Proteolysis by trypsin led to cleavage of a small peptide from the N-terminal end of toxin molecule. Trypsinized SEA displayed all kinds of biological activity characterizing the native toxin.
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http://dx.doi.org/10.1016/0020-711x(84)90073-9 | DOI Listing |
Proc Natl Acad Sci U S A
February 2025
Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research (NIOZ), Den Burg 1790 AB, The Netherlands.
Heterocytes, specialized cells for nitrogen fixation in cyanobacteria, are surrounded by heterocyte glycolipids (HGs), which contribute to protection of the nitrogenase enzyme from oxygen. Diverse HGs preserve in the sediment and have been widely used as evidence of past nitrogen fixation, and structural variation has been suggested to preserve taxonomic information and reflect paleoenvironmental conditions. Here, by comprehensive HG identification and screening of HG biosynthetic gene clusters throughout cyanobacteria, we reconstruct the convergent evolutionary history of HG structure, in which different clades produce the same HGs.
View Article and Find Full Text PDFMolecules
January 2025
Research and Innovation Centre, Fondazione Edmund Mach, 38098 San Michele all'Adige, TN, Italy.
This study explores the impact of geographical origin, harvest time, and cooking on the volatile organic compound (VOC) profiles of wild and reared seabream from the Adriatic and Tyrrhenian Seas. A Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) allowed for VOC profiling with high sensitivity and high throughput. A total of 227 mass peaks were identified.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Laboratory for Marine Drugs and Bioproducts, Qingdao Marine Science and Technology Center, Qingdao 266071, China. Electronic address:
Chloroanilines represent a class of persistent and highly toxic environmental pollutants, posing significant challenges for green remediation strategies. While P450BM3 monooxygenases are renowned for their ability to catalyze the monooxidation of inert C-H bonds, costly NAD(P)H and complex electron transport systems required for P450BM3 catalysis limit their practical applications. This study pioneers the development of innovative artificial biocatalysts by strategically engineering the active site of P450BM3.
View Article and Find Full Text PDFMar Drugs
January 2025
Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, 90123 Palermo, Italy.
In recent years, the invasive Atlantic blue crab () has increased its spread throughout the Mediterranean Sea, threatening native biodiversity and local economies. This study aimed to valorize sampled in Sicily by utilizing its exoskeleton as a source of chitosan, astaxanthin, and bio-phenolic compounds. These biomolecules were evaluated for their reducing, radical scavenging, and antitumor activity.
View Article and Find Full Text PDFPhysiol Plant
January 2025
College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, Liaoning Province, China.
Nitrogen (N) is a crucial macronutrient for plant growth, with nitrate as a primary inorganic N source for most plants. Beyond its role as a nutrient, nitrate also functions as a signalling molecule, influencing plant morphogenetic development. While nitrate utilization and signalling mechanisms have been extensively studied in model plants, the origin, evolution, and diversification of core components in nitrate uptake, assimilation, and signalling remain largely unexplored.
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