title: Fructosazine, a Polyhydroxyalkylpyrazine with Antimicrobial Activity: Mechanism of Inhibition against Extremely Heat Resistant Escherichia coli.
abstract: Fructosazine is a polyhydroxyalkylpyrazine recently reported to have antimicrobial activity against heat-resistant Escherichia coli AW 1.7. This study investigated fructosazine's antimicrobial mechanism of action and compared it to that of riboflavin. Fructosazine-acetic acid was effective in permeabilizing the outer membrane based on an evaluation of bacterial membrane integrity using 1-N-phenyl-1-naphthylamine and propidium iodide. The uptake of fructosazine by E. coli was pH-dependent with a greater uptake at pH 5 compared to pH 7 for all times throughout 16 h, except 2, 3, and 10 h. Fructosazine generates1O2, which is partially why it damages E. coli. DNA fragmentation was confirmed by fluorescence microscopy, and the fructosazine-acetic acid was the second most intense treatment after riboflavin-acetic acid. Electron microscopy revealed membrane structural damage by fructosazine at pH 5 and 7. This study provides evidence that fructosazine exerts antimicrobial action by permeabilizing the cell membrane, damaging membrane integrity, and fragmenting DNA.
authors: Department of Agricultural, Food and Nutritional Science, University of Alberta , 410 Agriculture/Forestry Centre, Edmonton, AB T6G 2P5 Canada.
authors: Abhishek
authors: A
authors: Bhattacherjee
authors: Department of Agricultural, Food and Nutritional Science, University of Alberta , 410 Agriculture/Forestry Centre, Edmonton, AB T6G 2P5 Canada.
authors: Yuliya
authors: Y
authors: Hrynets
authors: Department of Agricultural, Food and Nutritional Science, University of Alberta , 410 Agriculture/Forestry Centre, Edmonton, AB T6G 2P5 Canada.
authors: Mirko
authors: M
authors: Betti
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects; D004926:Escherichia coli / Q000737:chemistry / Q000187:drug effects*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D011719:Pyrazines / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D011719:Pyrazines; C017737:tagatosazine
keywords: DNA fragmentation; fructosazine; heat-resistant E. coli; outer membrane permeabilization; riboflavin; singlet oxygen