Study
The path of carbon in photosynthesis V: paper chromatography and radioautography of the products
Benson, Andrew A.; Bassham, James A.; Calvin, Melvin; Goodale, Theodore C.; Haas, Vernon A.; Stepka, William
Journal of the American Chemical Society, 1950
Algae photosynthesising in a flat illuminated vessel — the "lollipop" — were given carbon dioxide labelled with radioactive carbon-14, then killed in hot alcohol at precisely timed intervals from seconds upward. The soluble products were separated by two-dimensional paper chromatography and located by laying the paper on photographic film.
- Studied in
- Chlorella, Scenedesmus
- Sample size
- algal suspensions killed at intervals after exposure to labelled carbon dioxide
After a few seconds almost all the label was in a single three-carbon compound, 3-phosphoglycerate. Longer exposures spread the label through sugars and other intermediates, allowing the order of the reactions to be reconstructed.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Carbon fixation proceeds through a cycle beginning with the incorporation of carbon dioxide into a three-carbon acid.
How NatureHQ reads it
The method is the beautiful part. A metabolic pathway is a sequence you cannot see, so they marked the incoming carbon and froze the reaction at successive instants — a stop-motion film of chemistry, read off photographic film. Killing the algae at seconds rather than minutes is what makes the order recoverable; wait too long and the label is everywhere and tells you nothing.
- Green algae rather than higher plants, though the cycle proved general.
- The earliest time points were at the limit of what the apparatus could resolve.
- C4 and CAM plants fix carbon by additional routes not represented here.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Academic book publishersPublished as an academic monograph.
This reference was resolved automatically against Crossref on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-10.