Effect of Low Oxygen Tension upon Respiration and Fermentation of Isolated Cells

Abstract

Warburg has devised the methods which make it possible to examine the respiration of isolated cells at a constantly maintained equilibrium between the cell and the gas medium and to measure quantitatively the influence of various oxygen tensions upon respiration in such a way as to eliminate diffusion as a limiting factor. 1 By these methods Warburg has determined the effect of low oxygen tensions upon the respiration of bacteria and isolated animal cells. He found the rate of oxidation of the nucleated red blood cells of geese, which he examined at 0°C., to be unchanged at oxygen pressures varying between 5 and 75 mm. Hg. (=0.7 and 10 vol. % O₂). 2 In micrococcus candicans, at 1°C. the rate of respiration even at an oxygen tension of 10^-5 atm. (=0.0076 mm. Hg., =0.001 vol. % O₂) was the same as in air. 3 Also the respiration of non-nucleated red blood cells of rabbits poisoned by phenylhydrazin, examined at 38°C. showed no dependence upon oxygen tension. 4 Since these investigations it has been a generally accepted axiom of physiology that cell respiration is independent of variations of oxygen tension. 5

The only exceptions seemed to be the nitrogen-fixing bacteria and pneumococcus which were both examined with the Warburg methods under conditions of optimal gas diffusion. The relative rate of respiration of azotobacter at 2 vol. % O₂ and in air was 1 :2 (Meyerhof 6 ) and that of pneumococcus at 2 vol. % O₂ and in air was even 1:4.5 (Schlayer 7 ).