Cobalt chelatase Cobalt chelatase Cobalt chelatase () is an enzyme that catalyzes the chemical reaction The 4 substrates of this enzyme are ATP, hydrogenobyrinic acid a,c-diamide, Co, and HO, whereas its 4 products are ADP, phosphate, cob(II)yrinic acid a,c-diamide, and H. The aerobic cobalt chelatase (aerobic cobalamin biosynthesis pathway) consists of three subunits, CobT, CobN () and CobS (). Cobalamin (vitamin B12) can be complexed with metal via the ATP-dependent reactions (aerobic pathway) (e.g., in "Pseudomonas denitrificans") or via ATP-independent reactions (anaerobic pathway) (e.g., in "Salmonella typhimurium"). The corresponding cobalt chelatases are not homologous. However, aerobic cobalt chelatase subunits CobN and CobS
Cobalt radiation therapy. Cobalt-57 (Co-57 or Co) is a cobalt radioisotope most often used in medical tests, as a radiolabel for vitamin B uptake, and for the Schilling test. Cobalt-57 is used as a source in Mössbauer spectroscopy and is one of several possible sources in X-ray fluorescence devices. Nuclear weapon designs could intentionally incorporate Co, some of which would be activated in a nuclear explosion to produce Co. The Co, dispersed as nuclear fallout, is sometimes called a cobalt bomb. Cobalt is essential to the metabolism of all animals. It is a key constituent of cobalamin, also known as vitamin