title: Colorimetric detection of Shewanella oneidensis based on immunomagnetic capture and bacterial intrinsic peroxidase activity.
abstract: Rapid detection and enumeration of target microorganisms is considered as a powerful tool for monitoring bioremediation process that typically involves cleaning up polluted environments with functional microbes. A novel colorimetric assay is presented based on immunomagnetic capture and bacterial intrinsic peroxidase activity for rapidly detecting Shewanella oneidensis, an important model organism for environmental bioremediation because of its remarkably diverse respiratory abilities. Analyte bacteria captured on the immunomagnetic beads provided a bacterial out-membrane peroxidase-amplified colorimetric readout of the immunorecognition event by oxidizing 3, 3', 5, 5'-tetramethylbenzidine (TMB) in the present of hydrogen peroxide. The high-efficiency of immunomagnetic capture and signal amplification of peroxidase activity offers an excellent detection performance with a wide dynamic range between 5.0 × 10(3) and 5.0 × 10(6) CFU/mL toward target cells. Furthermore, this method was demonstrated to be feasible in detecting S. oneidensis cells spiked in environmental samples. The proposed colorimetric assay shows promising environmental applications for rapid detection of target microorganisms.
authors.affiliation: Guangdong Institute of Eco-environmental and Soil Sciences, Guangzhou 510650, P. R. China.
authors.forename: Junlin
authors.initials: J
authors.lastname: Wen
authors.affiliation: Guangdong Institute of Eco-environmental and Soil Sciences, Guangzhou 510650, P. R. China.
authors.forename: Shungui
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Guangdong Institute of Eco-environmental and Soil Sciences, Guangzhou 510650, P. R. China.
authors.forename: Junhua
authors.initials: J
authors.lastname: Chen
mesh_terms: D000907:Antibodies, Bacterial / Q000276:immunology; D003124:Colorimetry / Q000295:instrumentation*; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis* / Q000382:microbiology; D006861:Hydrogen Peroxide / Q000378:metabolism; D018189:Immunomagnetic Separation / Q000379:methods*; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000378:metabolism*; D020592:Shewanella / Q000302:isolation & purification*; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D000907:Antibodies, Bacterial; D014873:Water Pollutants; D006861:Hydrogen Peroxide; D009195:Peroxidase