1. The kinetics of ~tCO 2 incorporation into cellular intermediates was used to determine the primary pathway of carbon fixation by four genetically diverse unicellular blue-green algae. In each case label was first detected in 3-phosphoglycerate and then in compounds of the reductive pentose cycle.
Photoheterotrophy and chemoheterotrophy among unicellular blue-green algae
β Scribed by Rippka, R.
- Publisher
- Springer-Verlag
- Year
- 1972
- Weight
- 350 KB
- Volume
- 87
- Category
- Article
- ISSN
- 0003-9276
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β¦ Synopsis
Thirty eight axenic strains belonging to the Chroococcales were screened for the ability to grow photoheterotrophically in the light with glucose in the presence of 10 --5 3I DCMU, which inhibits photoautotrophic growth. Seven strains could do so, and four of them could also grow chemoheterotrophieally, though more slowly, with glucose in the dark. Six are members of the genus Aphanocapsa and one of the genus Chlorogloea. The remaining 31 strains examined appear to be obligate photoautotrophs. A quantitative study of the growth behaviour of one strain, Aphanocapsa 6714, fully confirmed its facultative photoheterotrophy and ehemoheterotrophy.
Reviewing the information then available, Holm-Hansen (1968) concluded that the blue-green algae are predominantly photoautotrophs. However, there are several well documented accounts of dark growth with sugars by heterocyst-forming strains (Allison and Hoover, 1937;
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