Premium
Enhanced cadmium resistance and accumulation in P seudomonas putida KT 2440 expressing the phytochelatin synthase gene of S chizosaccharomyces pombe
Author(s) -
Yong X.,
Chen Y.,
Liu W.,
Xu L.,
Zhou J.,
Wang S.,
Chen P.,
Ouyang P.,
Zheng T.
Publication year - 2014
Publication title -
letters in applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.698
H-Index - 110
eISSN - 1472-765X
pISSN - 0266-8254
DOI - 10.1111/lam.12185
Subject(s) - pseudomonas putida , phytochelatin , schizosaccharomyces pombe , biology , phytoremediation , pseudomonas , microbiology and biotechnology , biochemistry , bacteria , botany , yeast , gene , glutathione , saccharomyces cerevisiae , enzyme , genetics , contamination , ecology
Phytochelatins ( PC s) are cysteine‐rich peptides with high binding affinity for toxic metals. Expressing the PC synthase gene ( PCS ) in plant growth‐promoting bacteria may enhance its metal resistance and accumulation, consequently increasing phytoremediation efficiency in heavy metal pollution. In this study, PCS from S chizosaccharomyces pombe was cloned and expressed in P seudomonas putida KT 2440, which was confirmed by real‐time RT ‐ PCR through an increase in Sp PCS m RNA expression level when induced by 20 μ mol of CdCl 2 in the transformed P s. putida cells. The recombined strain KT 2440‐ Sp PCS exhibited enhanced Cd, Ag and H g resistance. Compared with the original strain, KT 2440‐ Sp PCS also displayed a threefold to fivefold increase in C d accumulation (14·32 μ mol g −1 to 17·38 μ mol g −1 ; dry weight) when grown in 30 and 50 μ mol C d C l 2 , along with an increase in nonprotein thiols. Further experiments showed significantly enhanced germination rates and growth of wheat seeds in 0·1 mmol to 1·0 mmol Cd when inoculated with KT 2440‐ SpPCS . This study shows potential use of P s. putida KT 2440‐ Sp PCS in plants to construct a symbiotic system for an enhanced phytoremediation of heavy metal‐contaminated environments. Significance and Impact of the Study The symbiotic system of using plant growth‐promoting bacteria P seudomonas putida to express phytochelatin synthase gene of S chizosaccharomyces pombe together in plants resulted in high heavy metal resistance and high accumulation capacity, suggesting potential enhancement in phytoremediation of heavy metal‐contaminated environments.