Mössbauer study of cobalt and iron in the cyanobacterium (blue green alga)

Mössbauer emission and absorption studies have been performed on cobalt and iron in the cyanobacterium (blue-green alga). The Mössbauer spectrum of the cyanobacterium cultivated with⁵⁷Co is decomposed into two doublets. The parameters of the major doublet are in good agreement with those of cyanocobalamin (vitamin B₁₂) labeled with⁵⁷Co. The other minor doublet has parameters close to those of Fe(II) coordinated with six nitrogen atoms. These suggest that cobalt is used for the biosynthesis of vitamin B₁₂ or its analogs in the cyanobacterium. The spectra of the cyanobacterium grown with⁵⁷Fe show that iron is in the high-spin trivalent state and possibly in the form of ferritin, iron storage protein.