title: Characterization of phosphate solubilizing bacteria in sediments from a shallow eutrophic lake and a wetland: isolation, molecular identification and phosphorus release ability determination.
abstract: The transformation of phosphorus (P) is a major factor of lake eutrophication, and phosphate releasing bacteria play an important role in the release process. Experiments were conducted to investigate P content and characterize phosphate solubilizing bacterial composition at the molecular level in a shallow eutrophic lake and a wetland. Results showed that P concentrations were relatively high and derived from agricultural runoff and domestic or industrial pollution. Enumeration and molecular identification of these strains indicated that these bacterial groups were abundant in the ecosystem and various kinds of bacteria participated in the phosphorus release process. Twelve phosphate solubilizing bacteria, including eight organic P-solubilizing bacteria (OPBs) and four inorganic P-solubilizing bacteria (IPBs), which belonged to three different families, were isolated and identified. Cupriavidus basilensis was found for the first time to have the ability to mineralize organic P (OP). Laboratory tests on P release ability revealed that IPBs were more effective at releasing P than OPBs. The most efficient IPB strain could accumulate over 170 mg·L-1 orthophosphate, while the equivalent OPB strain only liberated less than 4 mg·L-1 orthophosphate in liquid culture. The results obtained from this investigation should help clarify the roles of microorganisms in aquatic systems and the mechanisms of eutrophication.
authors.affiliation: Key Laboratory for Water Pollution Control and Environmental Safety, Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029, Zhejiang Province, China.
authors.forename: Yichao
authors.initials: Y
authors.lastname: Qian
authors.forename: Jiyan
authors.initials: J
authors.lastname: Shi
authors.forename: Yingxu
authors.initials: Y
authors.lastname: Chen
authors.forename: Liping
authors.initials: L
authors.lastname: Lou
authors.forename: Xinyi
authors.initials: X
authors.lastname: Cui
authors.forename: Rukun
authors.initials: R
authors.lastname: Cao
authors.forename: Pengfei
authors.initials: P
authors.lastname: Li
authors.forename: Jie
authors.initials: J
authors.lastname: Tang
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D002130:Calcium Phosphates / Q000378:metabolism; D049921:Cupriavidus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D005068:Eutrophication; D005618:Fresh Water / Q000382:microbiology*; D019015:Geologic Sediments / Q000382:microbiology*; D010710:Phosphates / Q000378:metabolism*; D010758:Phosphorus / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D053833:Wetlands
chemical_list: D002130:Calcium Phosphates; D010710:Phosphates; D012336:RNA, Ribosomal, 16S; D010758:Phosphorus; C020243:calcium phosphate