* Endosialidases: Versatile Tools for the Study of Polysialic Acid.
- Polysialic acid is an α2,8-linked N-acetylneuraminic acid polymer found on the surface of both bacterial and eukaryotic cells. Endosialidases are bacteriophage-borne glycosyl hydrolases that specifically cleave polysialic acid. The crystal structure of an endosialidase reveals a trimeric mushroom-shaped molecule which, in addition to the active site, harbors two additional polysialic acid binding sites. Folding of the protein crucially depends on an intramolecular C-terminal chaperone domain that is proteolytically released in an intramolecular reaction. Based on structural data and previous considerations, an updated catalytic mechanism is discussed. Endosialidases degrade polysialic acid in a processive mode of action, and a model for its mechanism is suggested. The review summarizes the structural and biochemical elucidations of the last decade and the importance of endosialidases in biochemical and medical applications. Active endosialidases are important tools in studies on the biological roles of polysialic acid, such as the pathogenesis of septicemia and meningitis by polysialic acid-encapsulated bacteria, or its role as a modulator of the adhesion and interactions of neural and other cells. Endosialidase mutants that have lost their polysialic acid cleaving activity while retaining their polysialic acid binding capability have been fused to green fluorescent protein to provide an efficient tool for the specific detection of polysialic acid.
Overview of verb base
The verb base has 3 senses (first 1 from tagged texts)
1. (75) establish, base, ground, found -- (use as a basis for; found on; "base a claim on some
2. base -- (situate as a center of operations; "we will base this project in the new lab")
3. free-base, base -- (use (purified cocaine) by burning it and inhaling the fumes)
Overview of adj based
The adj based has 2 senses (first 2 from tagged texts)
1. (3) based -- (having a base; "firmly based ice")
2. (1) based -- (having a base of operations (often used as a combining form); "a locally based
business"; "an Atlanta-based company"; "carrier-based planes")
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PubMed database: last updated on 2020-10-24 (c)sirasawa 2019