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ENZYMY BIORĄCE UDZIAŁ W MINERALIZACJI AZOTU ORGANICZNEGO

01/2005;

ABSTRACT S t r e s z c z e n i e . Etapy mineralizacji azotu organicznego w środowisku glebowym: proteoliza, amonifikacja, nitryfikacja. Enzymy biorące udział w tych procesach. Podstawy oznaczeń aktywności enzymów w glebie. Proponowane metody dla wyznaczenia aktywności wybranych enzymów w glebie. S ł o w a k l u c z o w e : gleba, minearalizacja azotu organicznego, metody oznaczania aktyw-ności enzymów Zasadnicza część masy azotu organicznego gleby wchodzi w skład trwałej substancji organicznej gleby – próchnicy jako frakcja białek i produktów ich hydrolizy, aminokwasów związanych z polifenolami, cukrami oraz połączeń tych produktów z minerałami gleby. Składnikami gleby zawierającymi azot są również kwasy nukleinowe, nukleoproteidy i aminocukry [6]. Związki organiczne azotu połączeń próchnicznych i dostających się do gleby w postaci resztek zwierzęcych i roślinnych substancji zawierających azot organiczny, ulegają złożonym przemianom biochemicznym. W tym procesie tworzą się dostępne dla roślin związki azotu mineralnego. We wszystkich sta-diach poszczególnych etapów ich przemian (proteolizy, amonifikacji, nitryfikacji, denitryfikacji) mają udział mikroorganizmy wytwarzające specyficzne enzymy wewnątrz żywych komórek lub enzymy pozakomórkowe wydzielane do środo-wiska, nagromadzone w glebie, osadzone na koloidach organicznych i mine-ralnych [27,28,41]. * Pracę wykonano w ramach projektu badawczego nr 3P04G 04324 finansowanego przez KBN w latach 2003-2005.

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