title: Pseudomonas fluorescens JH 70-4 promotes pb stabilization and early seedling growth of sudan grass in contaminated mining site soil.
abstract: A bacterial strain (JH 70-4) exhibiting plant growth promoting characteristics (indoleacetic acid production and 1-aminocyclopropane-1-carboxylate deaminase activity), as well as heavy metal(loid) (HM) tolerance and Pb precipitation, was isolated from HM-contaminated soil at an abandoned mine site. The bacterium was identified as Pseudomonas fluorescens based on 16S rDNA sequencing. The JH 70-4 strain induced precipitation of Pb as PbS nanoparticles, confirmed by X-ray diffraction. Solution pH, incubation time, and Pb concentration influenced removal and PbS formation. Inoculating contaminated soil with JH 70-4 decreased Pb availability; exchangeable Pb decreased while organic- and sulphide-bound Pb increased. The toxicity characteristic leaching procedure showed a 65% decrease in Pb in leachate 60 d after inoculating soil with JH 70-4. Shoot and root lengths of Sudan grass grown in the inoculated soil were greater than in the uninoculated soil. Findings suggest that microbial Pb fixation is a viable strategy for remediating soil and promoting plant growth for phytostabilization of contaminated sites.
authors.forename: Jaehong
authors.initials: J
authors.lastname: Shim
authors.forename: A Giridhar
authors.initials: AG
authors.lastname: Babu
authors.forename: Palanivel
authors.initials: P
authors.lastname: Velmurugan
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Shea
authors.forename: Byung-Taek
authors.initials: BT
authors.lastname: Oh
mesh_terms: D001673:Biodegradation, Environmental; D007854:Lead / Q000737:chemistry / Q000378:metabolism*; D011551:Pseudomonas fluorescens / Q000737:chemistry / Q000378:metabolism*; D036226:Seedlings / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism*; D045868:Sorghum / Q000502:physiology*
chemical_list: D012989:Soil Pollutants; D007854:Lead