SmtA is a metallothionein that can bind to heavy metal ions such as Cd(II). This SmtA is cloned from Synechococcus sp. PCC7942, a cyanobacterial strain. SmtA is a type II metallothionein with a reduced cys content.It was reported that marine cyanobacterium that does not originally harbor a homologous gene, when genetically engineered to express SmtA, could tolerate medium containing Cd(II), Zn(II) and Cu(II) (Sode et al., 1998).
The data above, taken from a paper (Sode et al., 1988), shows that a cyanobacterial strain was able to tolerate medium of high Cd(II) concentration when it harbored the smtA gene.
For our iGEM project this year, we have successfully observed that SmtA, expressed under a constitutive promoter (J23109) work very well. We plotted a graph of growth rate by looking at the OD595 every 1 hour, and compared the growth of wild type E. coli and SmtA expressing E. coli. As a result, we found that E. coli expressing SmtA grow better than the WT E. coli at a high Cd(II) concentration.
Sequence and Features
- 10Illegal PstI site found at 93
- 12Illegal PstI site found at 93
- 21COMPATIBLE WITH RFC
- 23Illegal PstI site found at 93
- 25Illegal PstI site found at 93
Illegal AgeI site found at 121
- 1000Illegal PstI site found at 93