Part:BBa_K2516000

Chromate reductase (codon-optimized for C. reinhardtii)

Chromate reductase (ChrR) is an oxidoreductase enzyme that is able to transfer 3 electrons towards Cr6+ anions, which results in reduction directly into Cr3+ ions. This reduction avoids production of side products such as Cr5+ and Cr4+, which are quite toxic to the cell. Both NADH and NADPH are equally utilized as electron donors. Other substrates that can be reduced: quinones (primary biological role), potassium ferricyanide, 2,6-dichloroindophenol, V5+, Mo6+, methylene blue, cytochrome c and U6+.

Reaction of electron transfer is the following:

2 NAD(P)H + Cr6+ + O2 = 2 NAD(P)+ + Cr3+ + superoxide

Flavin mononucleotide (FMN) serves as a cofactor molecule.

This enzyme lacks any post-translational modifications.

Optimal Conditions:

Optimum pH (for Cr6+) = 5

Optimum temperature (for Cr6+) = 35 degrees Celsius

Enzyme kinetics:

Vmax (for Cr6+) = 5 µmol/min/mg at optimal conditions

Km (for Cr6+) = 200 uM at optimal conditions

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 319
  
• 1000
  COMPATIBLE WITH RFC[1000]