Studies on the Properties of Cyclohydrolase from Human Leukocytes

Abstract
The occurrence of cyclohydrolase (5-10-methenyl-tetrahydrofolic acid+ H2O N10-f ormyl-tetrahydrof olic acid) has been demonstrated in human leukocytes and in white cells of patients with leukemia. Normal granulocytes contain less enzyme activity than human liver tissue (obtained by liver biopsy). Cells from patients with acute leukemia had markedly elevated enzyme activities.