Part:BBa_K3039020

PETase Reconstructed Ancestor 4

The enzymes PETase and MHETase were first discovered in Ideonella sakaiensis in 2016 by a group of researchers in Japan. These enzymes were found to degrade polyethylene terephthalate (PET) into its monomers, terephthalic acid (TPA) and ethylene glycol (EG). PETase degrades PET into Mono-(2-hydroxyethyl)terephthalic acid (MHET), Bis(2-Hydroxyethyl) terephthalate (BHET) and TPA, the main product being MHET. MHET is further degraded by MHETase into TPA and EG. We are aiming to use mutants of these enzymes to degrade the microfibres that are coming off clothing during washing cycles. The enzymes would be secreted into a filter that captures the microfibres. This is the sequence of one of the four reconstructed ancestors of PETase with a His tag attached to it. The sequence has been obtained through the method of ancestral reconstruction. The His tag has been used in order to more easily identify the enzyme.

Characterisation

In order to characterise our part and determine the rate of its activity and prove its functionality we have run a series of experiments. After transforming the Arctic Express, Rosetta Gami and BL21 DE3 strains of E. coli with our plasmid we induced the expression of the enzymes using IPTG. In order to confirm that the enzyme expression has been successful we ran a western blot which showed the presence of the enzyme in the soluble fractions of the sonicated cells. Afterwards the enzyme was purified and used in assays to show its functionality and determine the rate of its activity.

Expression in E.coli

Assays

PET Assay

Sequence and Features

Assembly Compatibility:

• 10
  INCOMPATIBLE WITH RFC[10]

  Illegal PstI site found at 433
  
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal PstI site found at 433
  
• 21
  COMPATIBLE WITH RFC[21]
• 23
  INCOMPATIBLE WITH RFC[23]

  Illegal PstI site found at 433
  
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal PstI site found at 433
  
• 1000
  COMPATIBLE WITH RFC[1000]