ANABOLISM BIOSYNTHESIS ANABOLISM REQUIRES LARGE AMOUNTS OF ENERGY
ANABOLISM BIOSYNTHESIS
ANABOLISM • REQUIRES LARGE AMOUNTS OF ENERGY • MOST ATP IS DEDICATED TO BIOSYNTHESIS DUE TO TURNOVER • CATABOLISM AND ANABOLISM ARE USUALLY BALANCED
MACROMOLECULES • • • PROTEINS NUCLEIC ACIDS POLYSACCHARIDES POLYMERS FROM MONOMERS REDUCED NUMBERS OF SUBUNITS REDUCES ENERGY REQUIREMENTS OF CELLS • 30 SMALL PRECURSORS
ASSEMBLY OF MACROMOLECULES • CONTAIN NECESSARY INFORMATIN TO SELF ASSEMBLE • RIBOSOMES
PHOTOSYNTHESIS LIGHT DEPENDENT VS LIGHT INDEPENDENT REACTIONS
THE LIGHT DEPENDENT REACTIONS OF PHOTOSYNTHESIS • SOME MICROBES CAN TRAP ENERGY OF LIGHT • PROVIDES ATP, NADH OR NADPH • USUALLY REDUCES AND INCORPORATES CARBON DIOXIDE IN LIGHT INDEPENDENT REACTIONS
LIGHT REACTIONS IN PLANTS, ALGAE & CYANOBACTERIA • PIGMENTS FOR LIGHT ABSORPTION • CHLOROPHYLL MOST IMPORTANT • FOUR RINGS WITH MAGNESIUM CENTER • CHLOROPHYLL A AND B • TRANSMIT GREEN LIGHT
TRANSMIT GREEN LIGHT
ACCESSORY PIGMENTS • CAROTENOIDS BETA CAROTENE XANTHOPHYLL FUCOXANTHIN • PHYCOBILIPROTEINS PHYCOERYTHRIN PHYCOCYANIN • 470 -630 NM LIGHT
ANTENNA • 300 CHLOROPHYLL MOLECULES • REACTION CENTER
PHOTOSYSTEM I & II
PHOTOSYSTEM I • PIGMENT 700 REACTION CENTER • TRANSFERRED TO ELECTRON TRANSPORT SYTEM • CYCLIC PATHWAY • NONCYCLIC PATHWAY
CYCLIC PHOSPHORYLATION • PHOTOSYSTEM I • REACTION CENTER CHLOROPHYLL – P 700 GETS EXCITED • GIVES ELECTRON TO ELECTRON TRANSPORT SYSTEM AND BACK TO P 700 • ATP MADE AT CYTOCHROME B 6
NONCYCLIC PHOTOPHOSPHORYLATION • • BOTH PHOTOSYSTEM I AND II P 700 GETS EXCITED GIVES ELECTRON TO FERRIDOXIN GOES DOWN ETS TO NADP+
PHOTOSYSTEM II • EXISTS TO SERVICE PHOTOSYSTEM I – PIGMENT 680 • MAKES SOME ATP • ELECTRONS ARE REPLACED BY PHOTOLYSIS
NONCYCLIC PHOTOPHOSPHORYLATION • ONE ATP & ONE NADPH FORMED • TAKES PLACE IN THYLAKOID MEMBRANE • GRANA THYLAKOIDS HAVE BOTH PHOTOSYSTEM I AND II • CYANOBACTERIA HAVE IN CELL MEMBRANE
COST OF LIGHT INDEPENDENT REACTIONS • THREE ATPS & TWO NADPHs TO REDUCE ONE CARBON DIOXIDE • FOUR ELECTRONS PASSING THROUGH PHOTOSYSTEMS WILL PRODUCE TWO ATPs AND TWO NADPHs • EXTRA ATP PROBABLY COMES FROM CYCLIC PHOTOPHOSPHORYLATION
LIGHT INDEPENDENT REACTION • KEY REACTION IS THE FIXATION OF CARBON BY THE CALVIN BENSON CYCLE BY ENZYME CALLED RUBISCO
CARBON FIXATION • ONLY AUTOTROPHS USE CARBON DIOXIDE AS SOLE OR MAIN CARBON SOURCE • NEEDS LOTS OF ENERGY • CAN OBTAIN FROM LIGHT DEPENDENT REACTIONS OR OXIDATION OF REDUCED INORGANIC MOLECULES
CALVIN BENSON CYCLE • STROMA OF EUKARYOTES
THE PHASES OF PHOTOSYNTHESIS • CARBOXYLATION • REDUCTION • REGENERATION
CARBOXYLATION PHASE RIBULOSE 1, 5 -BISPHOSPHATE CO 2 RUBISCO 3 -PHOSPHOGLYCERATE
REDUCTION PHASE PGA ATP PGAL NADPH
REGENERATION PHASE PGAL ATP RIBULOSE 1, 5 BIPHOSPHATE
HETEROTROPHIC SYNTHESIS OF SUGARS • FROM REDUCED ORGANIC MOLECULES • GLUCONEOGENESIS • SHARES SEVEN ENZYMES WITH GYCOLYSIS
IRREVERSIBLE GLYCOLYTIC REACTIONS • PHOSPHORYLATION OF GLUCOSE • CONVERSION OF FRUCTOSE 1, 6 BISPHOSPHATE FROM FRUCTOSE 6 PHOSPHATE • CONVERSION OF PHOSPHOPHENOPYRUVATE
ENZYMES • HEXOKINASE -- GLUCOSE 6 PHOSPHATE • PHOSPHOFRUCTOKINASE -- FRUCTOSE BISPHOSPHATASE • PYRUVATE KINASE -- PEP CARBOXYLASE & PYRUVATE CARBOXYLASE
PRODUCTS OF GLUCONEOGENESIS • FRUCTOSE & GLUCOSE • MANNOSE FROM FRUCTOSE
AMINO ACID SYNTHESIS • NITROGEN • CARBON SKELETON • PROVIDE ACETYL Co. A, ALPHA KETOGLUTARATE, OTHERS • GLYCOLYSIS, TCA, PENTOSE PHOSPHATE
FOR EXAMPLE OXALOACETATE CAN BE USED TO FORM THE FOLLOWING AMINO ACIDS • • LYSINE THREONINE ISOLEUCINE METHIONINE
LIPID BIOSYNTHESIS • GLYCEROL CAN BE SYNTHESIZED FROM DIHYDROXYACETONE PHOSPHATE • FATTY ACIDS ARE PRODUCED FROM TWO CARBON ACETYL Co. A MOLECULES • STEROIDS CAN BE SYNTHESIZED FROM ACETYL Co. A
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