the mystery of the altered gene professor peter m gresshoff [email protected]
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The MYSTERYof the altered GENEProfessor Peter M Gresshoff
www.cilr.uq.edu.au
NODULE FORMATION and
NITROGEN FIXATION
Professor Peter M Gresshoff
www.cilr.uq.edu.au
Nodules
Sucrose
1 mmNitrogen Gas
Ammonium Amino acids/protein/DNA/RNA
LEGUMES form NODULES
N2 + 16 ATP + 8 e- + 8 H+
2 NH3 + 16 ADP + H2
ENERGY:Solar (photosynthesis) or fossil (Haber-Bosch process)????
ENERGY:Solar (photosynthesis) or fossil (Haber-Bosch process)????
Protein-rich Seeds Protein-rich Seeds Cell Division Cell Division
Nitrogen Fixation Nitrogen Fixation
Endosymbiosis Endosymbiosis Colonisation Colonisation
Nodule induction Nodule induction
Root hairdeformation and curling Root hair
deformation and curling
Nodulation and nitrogen fixation are key processes for food, feed, and fuel
Nodulation and nitrogen fixation are key processes for food, feed, and fuel
Nod factors
Rhizobium
FLAVONES
Nod genes
Legume Root
RECEPTIONNFR1/5
Root hairsRhizobia
Curling root Curling root hairhair
Infection thread
Cell walls
Infection pocket
Inner cortex cells dividing
Cell nuclei
Vascular bundle
Rhizobia in cortex
Infection thread
Nodule Nodule primordiumprimordium
CortexCortexXylemXylem
PhloemPhloem
EpidermisEpidermis
Bacteroids
Vasculature
NucleusNodule cortex
Rhizobium cells (25,000)
The NODULATION processallows the conversion of atmospheric nitrogen gas to ammonia- which is a fertiliser for all plants
The NODULATION processallows the conversion of atmospheric nitrogen gas to ammonia- which is a fertiliser for all plants
Bacteroid withina legume nodule cells, engulfed by a plant membrane controlling nutrient and ammonia transport
Bacteroid withina legume nodule cells, engulfed by a plant membrane controlling nutrient and ammonia transport
malate
ammonia
aminoacids
N2 + 16 ATP + 8 e- + 8 H+
2 NH3 + 16 ADP + H2
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