Removal of cadmium ions during stationary growth phase by an extremely cadmium-resistant strain of Stenotrophomonas sp.
Stenotrophomonas sp. CD02 was isolated from a site that previously had been contaminated with high concentrations of the heavy metals cadmium (3 mg kg(-1)) and chromium (115 mg kg(-1)). This strain was able to grow on complex (Luria Bertani) medium containing high concentrations of cadmium ion (up to 4 mM). Additionally, it could remove up to 80% of the dissolved ions but only after reaching stationary growth phase. Strain CD02 also tolerated high concentrations of other heavy metals such as chromium, zinc, copper, nickel, and lead at levels more than 2 mM. Although strain CD02 can tolerate much higher cadmium concentrations than the three Stenotrophomonas maltophilia strains tested, they all possess resistance to the same range of antibiotics. This suggests that strain CD02 possesses a mechanism that allows it to tolerate and remove cadmium differently from those conferring resistance to antibiotics. Strain CD02 can be a suitable candidate for heavy metal bioremediation in contaminated environment because it is able to tolerate high concentration of heavy metals and remove cadmium aerobically.
Chien
Chih-Ching
CC
Graduate School of Biotechnology and Bioinformatics, Yuan Ze University, Chung-Li, Taiwan 320. ccchien@saturn.yzu.edu.tw
Hung
Chun-Wei
CW
Han
Chu-Ting
CT
D001483:Base Sequence; D001673:Biodegradation, Environmental; D002104:Cadmium / Q000378:metabolism*; D016000:Cluster Analysis; D003470:Culture Media / Q000737:chemistry; D024881:Drug Resistance, Bacterial / Q000502:physiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S; D017422:Sequence Analysis, DNA; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*; D013045:Species Specificity; D020588:Stenotrophomonas / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D013624:Taiwan; D018675:Toxicity Tests
D003470:Culture Media; D012336:RNA, Ribosomal, 16S; D012989:Soil Pollutants; D002104:Cadmium