#Id: 9297
#XL - Q Biochemistry
Nitrite reductase
Nitrite (NO2-) is a highly reactive, potentially toxic ion.
Plant cells immediately transport the nitrite into chloroplasts or plastids.
The enzyme nitrite reductase reduces nitrite to ammonium.
Leaf chloroplasts and root plastids contain different forms of nitrite reductase.
Each polypeptide contains two prosthetic groups, an iron-sulfur group and a specialized heme.
NO3-, high sucrose conc, and light induce the transcription of nitrite reductase mRNA.
Asparagine and glutamine repress the induction.
