
Part:BBa_K1218005
CysE (Ancestral)
CysE is a gene that makes a serine acetyltransferase essential to the production of cysteine. The serine acetyltransferase is responsible for the acetylation of serine to give O-acetylserine, a precursor for the production of cysteine. The ancestral version of the N terminal of the protein has been reconstructed using the seed sequences from the PFAM data base to create a phylogenetic tree using PhyML. We then used ProtTest to determine that the best ancestral reconstruction model was the WAG model, which we performed using PAML with Lazarus. See the Stanford-Brown 2013 iGEM wiki for process details and authenticity.
Due to limited data, we did not have enough information to create an ancestral version of the complete CysE gene. As a result, only the N terminus of the protein was reconstructed and is 53.3% similar to the modern one. We fused this to the extant E. coli C terminus. The C terminus is responsible for binding to other CysE generated proteins to make a heximer, whereas the N terminus is actually responsible for the reaction that creates cysteine.
Usage and Biology

Negative CysE control plated on M9 minimal media (Exhibits no colonies)
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25INCOMPATIBLE WITH RFC[25]Illegal AgeI site found at 478
Illegal AgeI site found at 684 - 1000COMPATIBLE WITH RFC[1000]
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