Aeration conditions affecting growth of purple nonsulfur bacteria in an organic wastewater treatment process.
Effects of aeration on purple nonsulfur bacteria (PnSB) were studied in photobioreactors. Bacterial community changes were analyzed by denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH). DGGE band pattern change was small and only few prominent bands were obtained at non-aeration condition. Sequencing results of the prominent DGGE bands obtained at this condition revealed that they represented mainly the PnSB, Rhodobacter sphaeroides and Rhodopseudomonas palustris. On the other hand, under aerated condition, some prominent bands originated from heterotrophs appeared but no proliferation of PnSB was observed. FISH was applied to detect PnSB and their population was quantified. Maximum PnSB ratio (up to 80%) was obtained both at non-aeration condition and at constant ORPs less than -200 mV. In the presence of DO, Rps. palustris was more competitive to chemoheterotrophs than Rb. sphaeroides.
Izu
K
K
Department of Urban Engineering, The University of Tokyo, Japan. kyoko.ono@aist.go.jp
Nakajima
F
F
Yamamoto
K
K
Kurisu
F
F
D019149:Bioreactors; D017753:Ecosystem; D004587:Electrophoresis, Agar Gel / Q000379:methods; D017404:In Situ Hybridization, Fluorescence; D008027:Light; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010100:Oxygen / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D012242:Rhodobacter sphaeroides / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D012241:Rhodopseudomonas / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D014865:Waste Disposal, Fluid; D014877:Water Pollution, Chemical
D010100:Oxygen