title: Suppression of type III effector secretion by polymers.
abstract: Bacteria secrete effector proteins required for successful infection and expression of toxicity into host cells. The type III secretion apparatus is involved in these processes. Previously, we showed that the viscous polymer polyethylene glycol (PEG) 8000 suppressed effector secretion by Pseudomonas aeruginosa. We thus considered that other viscous polymers might also suppress secretion. We initially showed that PEG200 (formed from the same monomer (ethylene glycol) as PEG8000, but which forms solutions of lower viscosity than the latter compound) did not decrease effector secretion. By contrast, alginate, a high-viscous polymer formed from mannuronic and guluronic acid, unlike PEG8000, effectively inhibited secretion. The effectiveness of PEG8000 and alginate in this regard was closely associated with polymer viscosity, but the nature of viscosity dependence differed between the two polymers. Moreover, not only the natural polymer alginate, but also mucin, which protects against infection, suppressed secretion. We thus confirmed that polymer viscosity contributes to the suppression of effector secretion, but other factors (e.g. electrostatic interaction) may also be involved. Moreover, the results suggest that regulation of bacterial secretion by polymers may occur naturally via the action of components of biofilm or mucin layer.
authors: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, Misasagi-Nakauchicho 5, Yamashina-ku, Kyoto 607-8414, Japan.
authors: Takashi
authors: T
authors: Ohgita
authors: Naoki
authors: N
authors: Hayashi
authors: Naomasa
authors: N
authors: Gotoh
authors: Kentaro
authors: K
authors: Kogure
mesh_terms: D036002:ADP Ribose Transferases / Q000235:genetics / Q000378:metabolism*; D000464:Alginates / Q000494:pharmacology; D058947:Bacterial Secretion Systems / Q000187:drug effects*; D001427:Bacterial Toxins / Q000378:metabolism; D018441:Biofilms; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D050296:Microbial Viability; D009077:Mucins / Q000494:pharmacology; D011092:Polyethylene Glycols / Q000494:pharmacology; D011108:Polymers / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*; D014783:Viscosity
chemical_list: D000464:Alginates; D058947:Bacterial Secretion Systems; D001427:Bacterial Toxins; C477521:ExoT protein, Pseudomonas aeruginosa; D020690:GTPase-Activating Proteins; D009077:Mucins; D011108:Polymers; D011092:Polyethylene Glycols; D036002:ADP Ribose Transferases
keywords: PEG; Pseudomonas aeruginosa; alginate; mucin; polymer; type III secretion