Part:BBa_K1342003

SmtA Part

this part is improved BBa_K519010 to use 3A Assembly. One silent mutation was introduced to eliminate PstI restriction enzyme site and was eliminated at bases 96 with C → T mutation.

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

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal AgeI site found at 121
  
• 1000
  COMPATIBLE WITH RFC[1000]