PSEUDOMONAS-AERUGINOSA NITRITE REDUCTASE (OR CYTOCHROME-OXIDASE) - ANOVERVIEW

The biochemistry and molecular biology of nitrite reductase, a key enz yme in the dissimilatory denitrification pathway of Ps aeruginosa whic h reduces nitrite to NO, is reviewed in this paper. The enzyme is a no n-covalent homodimer, each subunit containing one heme c and one heme d(1). The reaction mechanisms of nitrite and oxygen reduction are disc ussed in detail, as well as the interaction of the enzyme with its mac romolecular substrates, azurin and cytochrome c(551). Special attentio n is paid to new structural information, such as the chemistry of the d(1) prosthetic group and the primary sequence of the gene and the pro tein. Finally, results on the expression both in Ps aeruginosa and in heterologous systems are presented.