Difference between revisions of "Part:BBa K2275008"

Revision as of 16:54, 27 October 2017

PlacI-B0034-gudB

This composite part is composed of R0010, B0034 and K2275002 which encodes glutamate dehydrogenase (GudB) derived from Bacillus subtilis. First, to ensure whether the gene gudB can successfully express in E. coli or not, we used SDS-PAGE method to analyze the protein expression of GudB. The SDS-PAGE result is shown below. "WC" indicates whole cell, "S" for supernatant, "P" for pellet, and "C" indicates the control of sample without plasmid.

SDS-PAGE result shows that most protein is in form of pellet. Compared to the control, the expression level was much higher. However, no supernatant protein doesn't mean that it has no function. Hence, we added the ammonium and use Glutamate Colorimetric Assay Kit to detect the glutamate concentration. The Glutamate Enzyme Mix recognizes glutamate as a specific substrate and lead to proportional color development. The amount of glutamate can therefore be easily quantified by spectrophotometry at 450 nm. First, calibration curve is desired. By adding different concentration of glutamate and detecting the absorbance at 450 nm, we plot the relation between OD and glutamate concentration. The data of calibration curve is shown below.

The next step, we do three different experiment to test if the E. coli MG1655 harboring the Biobrick: BBa_K2275009 can convert the ammonium into glutamate. The testing result is shown below.

Sequence and Features