Collaborations
Overview
Collaboration – Mentoring iGEM team UNIFI
Figure 1: Skype meetings with iGEM UNIFI for a two-way collaboration.
In return for the mentorship, iGEM UNIFI helped us characterizing two BioBricks. To make sure that Escherichia coli is able to take up the unnatural nucleoside triphosphates from the cultivation media we had to introduce a heterologous transporter. This is due to a lack of nucleotide transporters in E. coli. Therefore, one of the BioBricks encodes a complete nucleotide transporter PtNTT2 (BBa_K2201000) originated from the algae Phaeodactylum tricornutumandusually. The second BioBrick is a truncated version missing the N-terminal signal peptide (BBa_K2201001). This N-terminal signal peptide leads to some kind of toxicity in E. coli. Through cultivation experiments we wanted to investigate the extent of toxicity suggesting that the strain expressing the full version of PtNTT2 grows weaker than the ones with the truncated version.
We started to cultivate the different strains in 50 mL media using flasks and measured the OD600 every 30 minutes during the exponential growing phase. Due to manual measurements our results showed big error values for the maximum growing rate µmax. This makes it hard to get a valid conclusion. Now iGEM UNIFI has the capacity to do the same cultivation experiment using a microscale bioreactor. This ensures automatic measurements for OD600 values which would decrease errors concerning µmax. This characterization from iGEM UNIFI would lead to a more accurate estimation of the toxicity of a full length version compared to a truncated version of PtNTT2.