Screening And Identification Of A Chromium-resistant Serratia Marcescens Strain S1 Study On The Characteristics Of Chromium Removal(?)

Objective:The wild strains capable of tolerating high concentrations of Cr?VI?were screened from the long-term Cr?VI?polluted environment,the strains were identified,the laboratory culture conditions of the strains were optimized,the drug sensitivity was analyzed,and the strain was preliminarily investigated?VI?characteristics.Methods:In this study,high-chromia-resistant strains were obtained after sampling,screening and acclimation.The bacterial culture,colony morphology,biochemical characteristics and 16S rDNA alignment were used to identify bacterial species.The growth of the strain was studied from temperature,pH and shaking culture speed.The characteristics of the strain were determined by drug-sensitive paper diffusion method.The Cr?VI?characteristics of the strain were studied by factors such as Cr?VI?concentration,temperature,pH and coexisting metals.Results:A wild strain capable of normal growth and red pigment production in LB broth containing 100 mg/L Cr?VI?was screened and identified as Serratia marcescens,named S1.In the absence of Cr?VI?,S1 has the strongest growth ability when the pH is 7.0,the temperature is 37°C,and the rotation speed is 200 rmp;S1 is sensitive to tetracycline,ampicillin,kanamycin,gentamicin;when the concentration of Cr?VI?is 100 mg/L,pH is 6.0⁷.0,temperature is 35⁴0°C,S1 has the strongest ability to remove Cr?VI?.Hg,Cd,As,and Cr³⁺can completely inhibit the growth of S1;Mn²⁺affects the growth of S1,in addition to Cr?VI?ability has a significant inhibition;while Cu²⁺inhibits the growth of S1 but enhances the ability of S1 to remove Cr?VI?.Conclusion:Serratia marcescens S1 can grow normally in the environment of high concentration of Cr?VI?,has strong ability to remove Cr?VI?.Temperature,pH and coexisting metal have certain influence to the groth and remove Cr?VI?ability of S1.