Part:BBa_K4171004

CysE*

Background

cysE* is the mutated version of cysE, which encodes for serine acetyltransferase that is originally inhibited by excessive cysteine (Cys). By altering five amino acids in the peptide sequence, CysE* (BBa_K4171004) is capable of transforming L-serine into O-acetyl-L-serine (OAS) continuously without being inhibited^[1].

Usage

We cultured E. coli with sodium selenite to replace sulfide and tested whether the enzymes that originally produce Cys can also synthesize selenocysteine (Sec) as well. Therefore, CysE* (BBa_K4171004) was mutated in order not to be downregulated by Sec. CysE* (BBa_K4171004) was overexpressed in E. coli to yield OAS, which was furthermore converted into Sec with sodium selenite through CysK (BBa_K4171000).

Fig. 1. In vivo Sec synthesis pathway

Characterization

Fig. 2. Confirmation of cysE* (BBa_K4171004) by PCR. M: Marker; Lane 1: cysE* (828bp).

Reference

[1]Nakamori S, Kobayashi SI, Kobayashi C, Takagi H. Overproduction of L-cysteine and L-cystine by Escherichia coli strains with a genetically altered serine acetyltransferase. Appl Environ Microbiol. 1998;64(5):1607-1611. doi:10.1128/AEM.64.5.1607-1611.1998

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 AgeI site found at 690
  
• 1000
  COMPATIBLE WITH RFC[1000]