Table 2.

Effectiveness of carbon sources as precursors forD. radiodurans growtha

Carbon and energy sourceGrowthbBiosynthetic pathwaycGenome datadDefect
Pyruvate+++AlanineComplete
ValineComplete
LeucineComplete
Oxaloactate++IsoleucineComplete
ThreonineComplete
LysineIncomplete dapABDF absent
MethionineComplete
Aspartic acidComplete
Phosphoglycerate+SerineIncomplete serCBabsent
GlycineComplete
CysteineIncomplete cysEJDN absent
  • a Acetate and lactate are effective growth substrates, while the tricarboxylic acid cycle intermediates malate, succinate, fumarate, and citrate, are ineffective.

  • b +++, excellent growth; ++, good growth; +, poor growth.

  • c The pathways are the entry points for biosynthesis for the amino acids indicated from the carbon and energy sources listed.

  • d For genomic comparisons, we used metabolic pathways present in E. coli. All of the genes necessary for histidine biosynthesis were present.