Difference between revisions of "Part:BBa K2449004"

Revision as of 22:03, 1 November 2017

cep94A controlled by LacI promoter

cep94A is a cellobiose phosphorylase, which efficiently phosphorylates the cellobiose at its β-linkage, resulting in the degradation of cellobiose to D-glucose and α-D-glucose-1-phosphate.

Expression of cep94A

An assay was conducted to to see the expression of the protein encoded by cen94A. It has a weight of 92,7 kDa, it is easily seen on the SDS-PAGE as can be seen on figure 1 This is on the high copi plasmid;pSB1C3.

Figure 1:A SDS-PAGE of BBa_2449004/cep94A compared with a negative control .The ladder used was SeeBlue™ Plus2 Pre-stained Protein Standard

It was further testet, if the protein could be expressed on a medium copy plasmid;pSB3K3 as seen in figure 2. It would be necessary to have on another plasmid with an other origin of replication, if two plasmids have to transformed into the same bacteria.

Figure 2: BBa_2449004/cep94A on medium copy plasmid pSB3K3 and on the high copy plasmid pSB1C3. The ladder used was SeeBlue™ Plus2 Pre-stained Protein Standard

This SDS-PAGE shows that it is possible to express the protein on pSB3K3.

Groth on cellobiose

The gene cep94A coding for cellobiose phosphorylase can make E.coli live on cellobiose on pSB1C3, this is shown in figure 3. The experiment shows it is not possible to use pSB3K3 plasmid.

Figure 3: BBa_2449004/cep94A on the pSB1C3 plasmid compared to the pSB3K3 plasmid.

Be aware that the generation time is reduced!

Figure 3: Cuvettes containing 2 mL of six different samples from the growth experiment after 72 hours. The cuvettes contains from left to right, BBa_2449904/cep94A in cellobiose media, BBa_2449904/cep94A with no carbon source, a negative control in cellobiose media, a control with no carbon source, BBa_523014/bglX in cellobiose media and BBa_523014/bglX with no carbon source

Conlusion

It is possible to make the E.coli live on cellobiose using this biobrick.

Sequence and Features