Polyamines Protect Escherichia coli Cells from the Toxic Effect of Oxygen

• Published in: Proceedings of the National Academy of Sciences - PNAS 2003-03, Vol.100 (5), p.2261-2265
• Main Authors: Chattopadhyay, Manas K., Tabor, Celia White, Tabor, Herbert
• Format: Article
• Language: English
• Subjects: Air; Amines - chemistry; Amino acids; Bacteria; Biological Sciences; Cadaverine - pharmacology; Cell Division; Cell growth; Cell membranes; Chromatography, High Pressure Liquid; Cultured cells; Cytoprotection; Disease; DNA - metabolism; Escherichia coli - metabolism; Escherichia coli - physiology; Hydrogen Peroxide - pharmacology; Mutation; Oxidative Stress; Oxygen; Oxygen - metabolism; Plasmids - metabolism; Polyamines; Polyamines - chemistry; Polyamines - metabolism; Polyamines - pharmacology; Putrescine - pharmacology; Slavic culture; Sorbitol - chemistry; Sorbitol - pharmacology; Spermidine - pharmacology; Sucrose - pharmacology; Superoxide Dismutase - pharmacology; Superoxides; Time Factors
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.2627990100

Wild-type Escherichia coli cells grow normally in 95%$O_2/5\%\>CO_2$. In contrast, cells that cannot make polyamines because of mutations in the biosynthetic pathway are rapidly killed by incubation in 95%$O_2/5\%\>CO_2$. Addition of polyamines prevents the toxic effect of oxygen, permitting cell survival and optimal growth. Oxygen toxicity can also be prevented if the growth medium contains an amino acid mixture or if the polyamine-deficient cells contain a manganese-superoxide dismutase (Mn-SOD) plasmid. Partial protection is afforded by the addition of 0.4 M sucrose or 0.4 M sorbitol to the growth medium. We also report that concentrations of H2O 2that are nontoxic to wild-type cells or to mutant cells pretreated with polyamines kill polyamine-deficient cells. These results show that polyamines are important in protecting cells from the toxic effects of oxygen.