Part:BBa_K732001

Synthetic Chorionic Gonadotropin, beta (synCG-β)

A synthetic version of human chorionic gonadotropin (hCG), a hormone produced during pregnancy. The nucleotide sequence was modified to maximize expression efficiency in bacteria and to conform to standard assembly, and the gene was chemically synthesized. The protein coded by this part is the beta subunit of hCG (hCG-β), which contains epitopes recognized by pregnancy tests. The full hCG dimer is also used as an ovulation inducer and can stimulate the production of testosterone in men.

This sequence can be used to express hCG for any downstream uses, and also as an output signal since it triggers pregnancy tests at low concentrations when properly folded.

Proof-of-principle

One application of this component is detection by pregnancy test.

When heterogeneous mixture of E. coli expressing BBa_K732001 and BBa_K732002 was lysed by either sonication or T7 infection, re-folded using a literature-based protocol, and applied to NewChoice pregnancy tests (purchased from Dollar Tree), positive results were visible.

Note that (a) there was some coloration around the positive band, and (b) the pregnancy tests were left overnight for bands to become visible. We hypothesize that the delayed read-time is necessary because the folding solution interferes with band visibility.

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
  INCOMPATIBLE WITH RFC[25]

  Illegal NgoMIV site found at 163
  Illegal NgoMIV site found at 207
  
• 1000
  COMPATIBLE WITH RFC[1000]