The effect of isotopic substitution on the living cell

College of Physicians and Surgeons, Department of Biochemistry, Columbia University, New York, N. Y., U.S.A., U.S.A..

Abstract

The discovery of deuterium and the subsequent concentration of the less abundant stable isotopes of hydrogen, oxygen and nitrogen has had a profound influence on the development of biochemistry. It has provided investigators with a procedure for labeling the naturally occurring organic constituents of the living cell and studying their transport and metabolism in the intact cell.

Replacement of H₂O by D₂O or H₂¹⁸O leads to interference in the delicately synchronized net of chemical reactions in the cell. This leads to inhibition of growth and division. It is likely that these phenomena are connected with changes in the tertiary structure of the proteins and the nucleic acids.