Studies on utilization of 2-ketoglutarate, glutamate and other amino acids by the unicellular alga Cyanidium caldarium

Arch Microbiol. 1976 Mar 19;107(2):133-8. doi: 10.1007/BF00446832.


Two strains of Cyandium caladarium which possess different biochemical and nutritional characteristics were examined with respect to their ability to utilize amino acids or 2-ketoglutarate as substrates. One strain utilizes alanine, glutamate or aspartate as nitrogen sources, and glutamate, alanine, or 2-ketoglutarate as carbon and energy sources for growth in the dark. The growth rate in the dark on 2-ketoglutarate is almost twice as high or higher than that on glutamate or alanine. During growth or incubation of this alga on amino acids, large amounts of ammonia are formed; however, ammonia formation is strongly inhibited by 2-ketoglutarate. The capacity of the alga and develops fully only when the cells are grown or incubated in the presence of glutamate.

MeSH terms

  • Alanine / metabolism
  • Amino Acid Oxidoreductases / analysis
  • Amino Acids / metabolism*
  • Ammonia / metabolism
  • Aspartic Acid / metabolism
  • Cell-Free System
  • Citric Acid Cycle
  • Cycloheximide / pharmacology
  • Darkness
  • Eukaryota / metabolism*
  • Glutamates / metabolism*
  • Ketoglutaric Acids / metabolism*
  • Light
  • Nitrate Reductases / metabolism


  • Amino Acids
  • Glutamates
  • Ketoglutaric Acids
  • Aspartic Acid
  • Ammonia
  • Cycloheximide
  • Amino Acid Oxidoreductases
  • Nitrate Reductases
  • Alanine