Research progress in structural biology of nitrate reductases Nar and Nap

Abstract:

Nitrate is a key component of the global nitrogen cycle and an important source of available nitrogen for plants. It is of great significance to study the transformation process of nitrate to improve the productivity of ecosystems, and dissimilatory nitrate reduction is the main path of nitrate transformation in the natural environment. At the same time, the large input of nitrate nitrogen has led to multiple eco-environmental problems, garnering increasing attention. Denitrification is the main process of nitrate nitrogen removal in the environment. Dissimilatory nitrate reduction as the first step in denitrification provides substrates for subsequent reduction reactions. Studying nitrate reduction processes can deepen the understanding of microbial denitrification. Dissimilatory nitrate reduction is co-catalyzed by membrane-bound nitrate reductase (Nar) and periplasmic nitrate reductase (Nap), which showcase differences in structure, cellular localization, reaction mechanism, gene regulation, and responses to environmental factors. Therefore, the two enzymes may have differences in the catalysis of nitrate reduction. This paper systematically compares Nar and Nap in the above aspects, aiming to improve our understanding of the development dynamics of nitrate in the system.

Key words:nitrate reductase;structure;reaction mechanism;gene regulation;environmental factors