Unexpected complexity of the ammonia monooxygenase in archaea.

ABSTRACT: Ammonia oxidation, as the first step of nitrification, constitutes a critical process in the global nitrogen cycle. However, fundamental knowledge of its key enzyme, the copper-dependent ammonia monooxygenase, is lacking, in particular for the environmentally abundant ammonia-oxidizing archaea (AOA). Here the structure of the enzyme is investigated by blue-native gel electrophoresis and proteomics from native membrane complexes of two AOA. Besides the known AmoABC subunits and the earlier predicted AmoX, two new protein subunits, AmoY and AmoZ, were identified. They are unique to AOA, highly conserved and co-regulated, and their genes are linked to other AMO subunit genes in streamlined AOA genomes. Modeling and in-gel cross-link approaches support an overall protomer structure similar to

SUBMITTER: Hodgskiss LH 

PROVIDER: S-EPMC10030591 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature