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Chitinases (, ''chitodextrinase'', ''1,4-beta-poly-N-acetylglucosaminidase'', ''poly-beta-glucosaminidase'', ''beta-1,4-poly-N-acetyl glucosamidinase'', ''poly() glycanohydrolase'', ''(1->4)-2-acetamido-2-deoxy-beta-D-glucan glycanohydrolase'') are hydrolytic enzymes that break down glycosidic bonds in chitin. As chitin is a component of the cell walls of fungi and exoskeletal elements of some animals (including worms and arthropods), chitinases are generally found in organisms that either need to reshape their own chitin or dissolve and digest the chitin of fungi or animals. == Species distribution == Chitinivorous organisms include many bacteria (Aeromonads, ''Bacillus'', ''Vibrio'', among others), which may be pathogenic or detritivorous. They attack living arthropods, zooplankton or fungi or they may degrade the remains of these organisms. Fungi, such as ''Coccidioides immitis'', also possess degradative chitinases related to their role as detritivores and also to their potential as arthropod pathogens. Chitinases are also present in plants (barley seed chitinase: , ); some of these are pathogenesis related (PR) proteins that are induced as part of systemic acquired resistance. Expression is mediated by the NPR1 gene and the salicylic acid pathway, both involved in resistance to fungal and insect attack. Other plant chitinases may be required for creating fungal symbioses. Although mammals do not produce chitin, they have two functional chitinases (Chitotriosidase - CHIT1 and acidic mammalian chitinase - AMCase) as well as chitinase-like proteins (such as YKL-40) that have high sequence similarity but lack chitinase activity. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「chitinase」の詳細全文を読む スポンサード リンク
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