The Assimilatory Nitrate-Reducing System and its Regulation

INTRODUCTION 169 ENZYMES OF THE NITRATE-REDUCING SYSTEM 171 Reduction of Nitrote to Nitrite 171 Ferredoxin-nitrate reductase •..•.•. •..• 171 NAD(P)H-nitrate reductase ....... ... 172 Reduction of Nitrite to Ammonia 177 Ferredoxin-nitrite reductase ... ........• 177 NAD(P)H-nitrite reductase 179 ENZYME LOCALIZATION AND THE PROVISION OF REDUCTANT 183 REGULATION OF NITRATE REDUCTION 185 Control of the Amount of Active Enzyme 186 Enzyme synthesis •.•.••.•.••.••. ..•....•...•..•..••.••.•. .••.•..•. 187 Enzyme activity 191 Control of Substrate Supply to Nitrate Reductase 193 CONCLUDING REMARKS 196