There's always room for improvement. Team REC-CHENNAI took the initiative to improve an existing composite part with a new promoter that would reduce the burden in cells during a promoted expression of enzymes. This will eventually lessen cell death. We chose the composite parts BBa_K1291071 and BBa_K2229300 to perform our improvement studies.
The existing composite part BBa_K1291071 has a burden value of range -0.6 ± 11.0% with the promoter J23119. The improved part of team REC-CHENNAI has a constitutive promoter J23116 which reduces the cell burden and thereby demotes cell death, with a burden range of -4.5 ± 2.8%. The other 2 composite parts, BBa_4509569 and BBa_4509869 were made for comparison studies between all the below mentioned parts to get efficient results when compared and analysed.
| BioBrick ID | Name | Type | Length | Description |
|---|---|---|---|---|
| BBa_J23119 | Constitutive Promoter | Regulatory | 35 bp | This promoter part can be used to tune the expression level of constitutively expressed parts. |
| BBa_B0034 | Strong RBS | RBS | 12 bp | RNA sequence found in mRNA to which ribosomes can bind and initiate translation. |
| BBa_K1291571 | HorseRadish Peroxidase Type C composite part | Translational Unit | 1059 bp | To amplify a weak signal and increase detectability of a target molecule. |
| BioBrick ID | Name | Promoter | Length of Promoter | Burden Value |
|---|---|---|---|---|
| BBa_K1291071 (Existing) |
HorseRadish Peroxidase Type C composite part | J23119 | 35 bp | -0.6 ± 11.0% |
| BBa_K4509569 | HorseRadish Peroxidase with constitutive promoter J23100 | J23100 | 35 bp | 20.0 ± 9.9% |
| BBa_K4509869 | HorseRadish Peroxidase with constitutive promoter J23106 | J23106 | 35 bp | 3.5 ± 8.7% |
| BBa_K4509420 | HorseRadish Peroxidase with constitutive promoter J23116 | J23116 | 35 bp | -4.5 ± 2.8% |
In order to increase the expression of Acid phosphatase on the cell surface, Team REC-CHENNAI improved the existing part BBa_K2229300. The promoter in BBa_K2229300 has a cell burden value of 20.0 ± 9.9%. By replacing the constitutive promoter J23100 with the constitutive promoter J23118, the burden value reduces to a range of -0.1 ± 3.8%. The new part with improved characteristics is BBa_K4509469.
| BioBrick ID | Name | Promoter | Length of Promoter | Burden Value |
|---|---|---|---|---|
| BBa_K2229300 (Existing) |
Dual Expressing Construct of CsgD and OmpR234 | J23100 | 35 bp | 20.0 ± 9.9% |
| BBa_K4509469 | csgD and OmpR234 Dual Expression | J23118 | 35 bp | -0.1 ± 3.8% |