title: Rapid solubilization of insoluble phosphate by a novel environmental stress-tolerant Burkholderia vietnamiensis M6 isolated from ginseng rhizospheric soil.
abstract: We isolated and characterized novel insoluble phosphate (P)-solubilizing bacteria tolerant to environmental factors like high salt, low and high pHs, and low temperature. A bacterium M6 was isolated from a ginseng rhizospheric soil and confirmed to belong to Burkholderia vietnamiensis by BIOLOG system and 16S rRNA gene analysis. The optimal cultural conditions for the solubilization of P were 2.5% (w/v) glucose, 0.015% (w/v) urea, and 0.4% (w/v) MgCl(2).6H(2)O along with initial pH 7.0 at 35 degrees C. High-performance liquid chromatography analysis showed that B. vietnamiensis M6 produced gluconic and 2-ketogluconic acids. During the culture, the pH was reduced with increase in gluconic acid concentration and was inversely correlated with P solubilization. Insoluble P solubilization in the optimal medium was about 902 mg l(-1), which was approximately 1.6-fold higher than the yield in NBRIP medium (580 mg l(-1)). B. vietnamiensis M6 showed resistance against different environmental stresses like 10-45 degrees C, 1-5% (w/v) salt, and 2-11 pH range. The maximal concentration of soluble P produced by B. vietnamiensis M6 from Ca(3)(PO(4))(2), CaHPO(4), and hydroxyapatite was 1,039, 2,132, and 1,754 mg l(-1), respectively. However, the strain M6 produced soluble P with 20 mg l(-1) from FePO(4) after 2 days and 100 mg l(-1) from AlPO(4) after 6 days, respectively. Our results indicate that B. vietnamiensis M6 could be a potential candidate for the development of biofertilizer applicable to environmentally stressed soil.
authors.affiliation: College of Natural Resources and Life Science, Pusan National University, Miryang, South Korea.
authors.forename: Ki-Hyun
authors.initials: KH
authors.lastname: Park
authors.forename: O-Mi
authors.initials: OM
authors.lastname: Lee
authors.forename: Ho-Il
authors.initials: HI
authors.lastname: Jung
authors.forename: Jin-Ha
authors.initials: JH
authors.lastname: Jeong
authors.forename: Young-Dong
authors.initials: YD
authors.lastname: Jeon
authors.forename: Dae-Youn
authors.initials: DY
authors.lastname: Hwang
authors.forename: Chung-Yeol
authors.initials: CY
authors.lastname: Lee
authors.forename: Hong-Joo
authors.initials: HJ
authors.lastname: Son
mesh_terms: D019117:Burkholderia / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005942:Gluconates / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D005894:Panax / Q000382:microbiology*; D010710:Phosphates / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013696:Temperature
chemical_list: D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005942:Gluconates; D010710:Phosphates; D012336:RNA, Ribosomal, 16S; C008229:2-ketogluconate; C030691:gluconic acid