An endochitinase from centrifuged autolyzed cultures of Aspergillus nidulans has been purified 100 times. The enzyme has Mw 27,000, pI of 4.8 units, pH optimum around 5 pH units. It is unstable at temperature greater than 70 degrees C and does not have a cation requirement. It is inhibited by Hg2+, Cu2+, Ca2+ and Ag+ and it does not have muramidase activity. The enzyme depolymerizes chitin rapidly with production of high molecular weight polysaccharides, and then slowly degrades these with production of N,N'-diacetylchitobiose. The enzyme hydrolyzes N,N',N''-triacetylchitotriose with production of N,N'-diacetylchitobiose and N-acetylglucosamine and this hydrolysis is inhibited by other chitin oligomers and N-acetylglucosamine. This enzyme hydrolyzes in the same way the chitin obtained from the cell wall of Aspergillus nidulans.
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http://dx.doi.org/10.1016/0378-1097(89)90088-8 | DOI Listing |
Int J Mol Sci
December 2024
Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Moscow 119071, Russia.
The filamentous fungus (anamorph ) has been shown to be an efficient producer of secreted cellulases, used in biorefinery processes. Understanding the mechanisms of regulation of cellulase gene expression in the fungus is a current task in industrial biotechnology, since it allows for targeted changes in the composition of the complex secreted by the fungus. Expression of cellulase genes in fungi is regulated mainly at the level of transcription via pathway-specific transcription factors (TF), the majority of which belong to the Zn(II)2Cys6 family of zinc binuclear cluster proteins.
View Article and Find Full Text PDFBiomolecules
November 2024
Área de Bioquímica y Biología Molecular, Departamento de Biología Molecular, Universidad de León, 24007 León, Spain.
Testosterone holds significant medical and economic importance, with the global market for testosterone replacement therapies valued at approximately USD 1.9 billion in 2023. This hormone is essential for the development and maintenance of male sexual characteristics as well as bone and muscle health.
View Article and Find Full Text PDFBioorg Chem
December 2024
Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, PR China. Electronic address:
Nidustrin A (1), the first cysteine-retained emestrin featuring a unique sulfur-containing 18-membered macrocyclic lactone, along with four biogenetically related compounds (2-5), and one known analogue secoemestrin C (6), were isolated from the large-scale culture of Aspergillus nidulans, an endophytic fungus derived from the Whitmania pigra. Compounds 2 and 3 represent the second examples of noremestrin besides the previously reported noremestrin A, and the single crystal X-ray diffraction analysis of compound 2 provided solid evidence for the intriguing skeleton of noremestrin. Their structures were determined by extensive spectroscopic data, electronic circular dichroism calculations, and single-crystal X-ray diffraction.
View Article and Find Full Text PDFMicrob Cell Fact
January 2025
Botany and Microbiology Department, Faculty of Science, Benha University, Benha, Egypt.
Background: Because the process is cost-effective, microbial pectinase is used in juice clearing. The isolation, immobilization, and characterization of pectinase from Aspergillus nidulans (Eidam) G. Winter (AUMC No.
View Article and Find Full Text PDFWorld J Microbiol Biotechnol
December 2024
Nanjing Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
The majority of Aspergillus fumigatus reproduction occurs asexually, with large numbers of conidiophores producing small hydrophobic conidia dispersed aerially. When healthy hosts inhale conidia, the mucosal cilia and phagocytosis by the innate immune system can remove them. However, in immunocompromised hosts, the conidia are not removed, which allows them to germinate, forming mycelium that invades host tissues and causes disease.
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