FACTORS AFFECTING THE VIABILITY OF AIR-BORNE BACTERIA: V. THE EFFECT OF DESICCATION ON SOME METABOLIC SYSTEMS OF ESCHERICHIA COLP

Abstract

The effect of desiccation on the ability of Escherichia coli to carry out oxidations, decarboxylations, and adaptive enzyme synthesis has been studied. Changes in cell metabolism due to drying were studied; and also the influence on such changes of protecting the cells with inositol. Dehydration brought about the release of 260-mμ absorbing material from the cell, the amount released being increased in the presence of inositol. Dehydration reduced amino acid oxidation and increased decarboxylation and glucose oxidation. Protecting the cells against death with inositol not only failed to prevent these changes but, with the exception of glucose oxidation, made them more pronounced. The synthesis of adaptive β-galactosidase was found to be greatly inhibited by desiccation and this inhibition could be prevented by inositol. It is suggested that a structural change in the nucleoproteins concerned in protein synthesis is responsible for the death of dried cells rather than damage to their membrane.