Part:BBa_K2669001

Bilirubin-inducible UnaG+6xHis-tag+Flexible linker

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]

This is a basic part that when placed in combination with the proper RBS/terminator/promoter (such as in Part:BBa_K2669000) will express UnaG with a histidine tag and a flexible linker with which one can attach another protein.

This part is a correction of the Uppsala 2016’s Part:BBa_K2003011, which we noticed had a misplaced start codon. This misplaced start codon caused two major problems:

1) This would lead to a reduction in UnaG expression due to a large space being created between the RBS and the start codon

2) This would lead to no histidine tag being expressed

We have shown that our new improved part does in fact express a histidine tag and has higher expression levels than the old part Part:BBa_K2003011.

It is also important to note that a stop codon was added after the GSG linker since this part was used to submit a composite part (Part:BBa_K2669000) in order to test expression levels of UnaG and to test if the histidine tag indeed worked after our change. If you would like to use this part to link UnaG to another protein, it is strongly advised to delete the "taa" stop codon at the end of the sequence .

Background and Potential Usage

UnaG is a unique chromoprotein since it expresses fluorescent signal when in contact with bilirubin. This means (unlike most other chromoproteins) it can be used as a reporter in anaerobic environments or potentially in environments where bilirubin is naturally present, such as the intestines.

Source

This part contains the sequence from Part:BBa_K2003011, with a change to the start codon location. The original source of UnaG is from the paper “A Bilirubin-Inducible Fluorescent Protein from Eel Muscle” by Kumagai A et. al, which characterized the UnaG protein from the muscle of a species of Japanese eel.