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ASSIMILATION OF MINERAL NUTRIENTS. NUTRIENT ASSIMILATION: THE INCORPORATION OF MINERAL NUTRIENTS INTO ORGANIC COMPOUNDS. ASSIMILATION OF SOME NUTRIENTS—PARTICULARLY NITROGEN AND SULFUR—REQUIRES A COMPLEX SERIES OF BIOCHEMICAL REACTIONS.
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ASSIMILATION OF MINERAL NUTRIENTS • NUTRIENT ASSIMILATION: THE INCORPORATION OF MINERAL NUTRIENTS INTO ORGANIC COMPOUNDS. • ASSIMILATION OF SOME NUTRIENTS—PARTICULARLY NITROGEN AND SULFUR—REQUIRES A COMPLEX SERIES OF BIOCHEMICAL REACTIONS. • ASSIMILATION OF OTHER NUTRIENTS INVOLVES THE FORMATION OF COMPLEXES WITH ORGANIC COMPOUNDS (e.g. Mg2+ ASSOCIATION WITH CHLOROPHYLL).
NITRATE REDUCTASE REACTIONNO3- + NAD(P)H + H+ + 2e- NO2- + NAD(P)+ + H2O
NITRITE REDUCTASE REACTIONNO2- + 6Fdred + 8H+ + 6e-NH4+ + 6Fdox + 2 H2O • PLANTS CAN ASSIMILATE NITRATE IN BOTH ROOTS AND SHOOTS
CONVERSION OF AMMONIUM TO AMINO ACIDS REQUIRES TWO ENZYMES (GOGAT) (GS)
SUMMARY OF PROCESSES INVOLVED IN ASSIMILATION OF MINERAL NITROGEN (Leaf) “Photoassimilation”
Root Nodule Development Isoflavonoids, betaines Leghemoglobin
NOD FACTORS PRODUCED BY BACTERIA ACT AS SIGNALS FOR SYMBIOSIS NOD FACTORS ARE LIPOCHITIN OLIGOSACCHARIDES
THE NITROGENASE REACTION(oxygen-sensitive) N2 + 8 e- + 8 H+ + 16 ATP 2 NH3 + H2 + 16 ADP + 16 Pi
AMIDES (ASPARAGINE AND GLUTAMINE) AND UREIDES ARE THE TRANSPORTED FORMS OF NITROGEN IN LEGUMES UREIDES