Team:Pittsburgh CSL/Parts



New Part Shewanella ldhA gene BBa_K2565001

This composite part is used to constitutively express high levels of Shewanella oneidensis MR-1 fermentative lactate dehydrogenase NADH dependent ldhA (BBa_K2565000) in E. coli, locus tag SO_0968.

The left figure shows that the media with E. coli constitutively expressing ldhA contains more lactate than LB only. The right figure shows the amount of lactate in the media of cultures so that when Shewanella and E. coli are grown together there is more lactate in the media. The MG1655 strain of E. coli does not express the Shewanella ldhA gene.

This graph shows the voltage produced by microbial fuel cells (MFC) in 15 hours. The MFC with Shewanella and E. coli produced more voltage than Shewanella alone. The MFC with Shewanella and E. coli expressing Shewanella ldhA produced more consistent voltage than E. coli without Shewanella ldhA.

Improved Part Consensus ProU promoter BBa_K2467002

The biosensor from the CMUQ 2017 team was selected for improved characterization (Part: BBa_K2467002). Five different concentrations of NaCl were added to tryptone and yeast extract (same as LB) and E.coli containing the biosensor plasmid and were grown overnight in triplicate. After 18 hours the red fluorescence of 100ul of culture was measured in a TECAN m1000 plate reader set for excitation/emission wavelengths of 584/607nm at a gain of 100.

Figure showing fluorescence readings of RFP reporter for ProU consensus promoter. Error bars show standard error of the mean.

These results show that the biosensor is sensitive from at low osmolarity (0-100mM NaCl). At more normal osmolarity (100-400mM NaCl) there is no difference (normal LB is 170mM NaCl).

Cultures of the osmolarity sensor