RBS + bglX (E. coli perisplasmic β-glucosidase)
This is the E. coli β-glucosidase gene bglX. The part contains the native Ribosome Binding Site.
The part was made using the strategy outlined in BBa_K523000, and therefore contains 4 extra bases at the 5' end which generate a BglII restriction site.
Usage and Biology
The product protein is believed to be periplasmic. β-glucosidase cleaves β(1→4) bonds, i.e. those found in the disaccharide cellobiose.
The SignalP program predicts that a 20 amino acid localisation signal (at the N terminal) is cleaved off before the protein reaches its mature form.
Edinburgh 2011 carried out some experiments on this part under the control of the lac promoter - see details at part BBa_K523014.
Sequence and Features
- 10COMPATIBLE WITH RFC
- 12COMPATIBLE WITH RFC
- 21COMPATIBLE WITH RFC
- 23COMPATIBLE WITH RFC
- 25Illegal AgeI site found at 1658
Illegal AgeI site found at 1880
Illegal AgeI site found at 2069
- 1000COMPATIBLE WITH RFC
Functional Parameters: Austin_UTexas
Burden Imposed by this Part:
Burden is the percent reduction in the growth rate of E. coli cells transformed with a plasmid containing this BioBrick (± values are 95% confidence limits). This BioBrick did not exhibit a burden that was significantly greater than zero (i.e., it appears to have little to no impact on growth). Therefore, users can depend on this part to remain stable for many bacterial cell divisions and in large culture volumes. Refer to any one of the BBa_K3174002 - BBa_K3174007 pages for more information on the methods, an explanation of the sources of burden, and other conclusions from a large-scale measurement project conducted by the 2019 Austin_UTexas team.
This functional parameter was added by the 2020 Austin_UTexas team.
Thessaly 2021 Improvement
Experimental Use and Experience
This year we decided to improve BBa_K523002, by altering the native signal peptide sequence of BglX, a periplasmic beta glucosidase, with a N20- signal peptide, which translocates the protein extracellularly. With this improved part BBa_K3866032 , we engineered bacteria that are able to valorize cellobiose and use it as a carbon source.
N20-bglX bacteria grow more and faster than the SP-bglX and EMPTY bacteria in a 24-hour time-frame and with cellobiose as the only carbon resource. The engineered enzyme provides an advantage in situations where cellobiose is the only abundant carbon source. Also, N20-bglX bacteria reach an exponential-like phase much quicker than the native peptide or the empty vector control bacteria, which means quicker valorization cellobiose and update of glucose by the cell.