Ribonucleotide reductase activity in vitamin B12-deficient Euglena gracilis.
The ribonucleotide reductase activities in vitamin B12-sufficient and -deficient cells of Euglena gracilis were measured. We found that the cells progress into vitamin B12 deficiency the enzyme activity increases, reaching a maximum value of 20-fold in advanced deficiency. No signigicant differences in the activities were found to result as a consequence of different growth conditions. We propose that the increased activity in vitamin B12-deficient cells is due to an increase in enzyme protein.
D003624:Darkness; D005056:Euglena gracilis / Q000201:enzymology*; D012264:Ribonucleotide Reductases / Q000378:metabolism*; D014805:Vitamin B 12 / Q000378:metabolism*
D012264:Ribonucleotide Reductases; D014805:Vitamin B 12