AIMS: Melatonin is a hormone produced by the pineal gland and that affects the response of various cell membranes to an oxidative stimulus. METHODS AND RESULTS: The present study evaluates the hydrophobic characteristics of Escherichia coli in response to melatonin (100 nmol l(-1), 200 micromol l(-1)) and to vitamin E (5 mg dl(-1)). A reduction was found in the surface hydrophobicity of E. coli at concentrations of 200 micromol l(-1) melatonin in a Müeller-Hinton (MH) broth. These effects were modified when a protein synthesis inhibitor (chloramphenicol) was added at sub-lethal concentrations to the broth. Vitamin E produced a greater diminution in surface hydrophobicity than melatonin. The adherence of E. coli to nitrocellulose filters increased in the presence of melatonin + chloramphenicol, and vitamin E. The effects observed were independent of the concentration of iron in the broth. CONCLUSION: Oxidative stress plays an important role in modifying the surface characteristics of E. coli, which could affect the micro-organism's capacity to adhere to epithelia. SIGNIFICANCE AND IMPACT OF THE STUDY: We think that the oxide reduction potential of the host may be a determinant factor in the bacterial colonization of animal tissue.
AIMS: Melatonin is a hormone produced by the pineal gland and that affects the response of various cell membranes to an oxidative stimulus. METHODS AND RESULTS: The present study evaluates the hydrophobic characteristics of Escherichia coli in response to melatonin (100 nmol l(-1), 200 micromol l(-1)) and to vitamin E (5 mg dl(-1)). A reduction was found in the surface hydrophobicity of E. coli at concentrations of 200 micromol l(-1) melatonin in a Müeller-Hinton (MH) broth. These effects were modified when a protein synthesis inhibitor (chloramphenicol) was added at sub-lethal concentrations to the broth. Vitamin E produced a greater diminution in surface hydrophobicity than melatonin. The adherence of E. coli to nitrocellulose filters increased in the presence of melatonin + chloramphenicol, and vitamin E. The effects observed were independent of the concentration of iron in the broth. CONCLUSION: Oxidative stress plays an important role in modifying the surface characteristics of E. coli, which could affect the micro-organism's capacity to adhere to epithelia. SIGNIFICANCE AND IMPACT OF THE STUDY: We think that the oxide reduction potential of the host may be a determinant factor in the bacterial colonization of animal tissue.
Authors: Alessandro Bidossi; Monica Bortolin; Marco Toscano; Elena De Vecchi; Carlo L Romanò; Roberto Mattina; Lorenzo Drago Journal: PLoS One Date: 2017-07-31 Impact factor: 3.240