Isolation, Identification and Adsorption Characteristics of a Cd-tolerant Bacterium
XU Shuxia
DU Wentao
WANG Xiaoya
ZHANG Jiran
ZHANG Shimin
WU Kun
Abstract：A Cd-tolerant strain was isolated from the pesticide polluted soil,on the basis of morphological observation,physiological and biochemical characteristics,16S rRNA gene sequence and phylogenetic analysis,the strain was identified as Enterobacter ludwigii,and named as EM1,so as to provide strain for remediation of Cd polluted water and soil.The optimal Cd2+ concentration of strain EM1 against Cd2+ was 50 mg/L,the optimum growth temperature of strain EM1 against Cd2+ was 35 ℃,and the optimum pH value of strain EM1 against Cd2+ was about 6.0.Under this condition,the Cd2+ adsorption rate of EM1 was the highest,reached 92％.The SEM results showed that in the process of adsorption of Cd2+,the morphology of the strains was changed,and a large number of extracellular polymeric substances were secreted on the strain surface.Infrared scanning analysis showed that under the Cd2+ stress condition,the cell walls structure had not changed,and hydroxy,N-H,C-H,C-O-C and aminoacyl were confirmed to be the key functional groups for the strain to adsorb Cd2+.
Keywords：Cd-tolerant bacteriumEnterobacter ludwigiibioadsorptionelectron microscopic observationinfrared spectroscopy analysis
Publication Date：2017-05-02
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：7( 71-76,83 )