Effects of Hyperoxia on Sulfhydryl Concentration of 'Escherichia coli'.
Abstract
The concentration of reduced sulfhydryl (SH) in cell-free extracts of Escherichia coli grown with air as the gas phase was 26.8 plus or minus 1.2 mnoles SH/mg soluble protein. Exposure of bacteria to 1 ata of oxygen where growth continued but at a reduced rate, or to 6.2 ata of oxygen where growth was completely stopped, did not result in significant changes in intracellular SH concentration. Cell-free extracts exposed to 1.2 ata of oxygen resulted in SH oxidation at 0.5%/min, compared to 0.75%/min for reduced glutathione at 4.2 ata. Fractionation of cell-free extracts by ultrafiltration indicated that approximately 92% of the measurable SH-groups were protein-related. These data indicate that neither oxidation of intracellular SH, nor the relatively slow oxidation of surface SH-groups is a significant factor in the rapid growth inhibition of E. coli by hyperoxia. Bacterial reversal of possible intracellular SH oxidation during the interval between decompression and extraction was not excluded. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1972
- Accession Number
- AD0746193
Entities
People
- Jack L. Stees
- Olen R. Brown
Organizations
- University of Missouri