BM1000 Lecture 8: Lecture 8
Document Summary
Fixed in the calvin-bensoncycle (photosynthetic carbon reduction cycle - pcr) All reactions of the calvin-benson-bassham cycle take place in the chloroplast stroma. Co2 is fixed by rubisco - an enzyme (a protein produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction). The cycle produces 3-carbon sugars which are converted to carbohydrates (simple sugars such as glucose and sucrose, or polysaccharides such as starch). Green algae grown in continuous cultures was placed in a glass holder. Carbon-14 labelled co2 was injected for various periods. The algae were killed by dropping into boiling ethanol. Radiolabelled metabolites were analysed using two-dimensional paper chromatography. Give plants a pulse of 14co2 followed by a 12co2. Watch the pulse of radioactivity move sequentially from one metabolite pool to the next. 109 tonnes on earth (about 160kg per homo sapiens) the most common protein on the planet. 3. 5 turnovers s-1 (carbonic anhydrase does 600,000) (co2.
