Part:BBa_K1497001

CHS - Chalcone Synthase from Gerbera

The Chalcone Synthase catalyzes the reaction from 4-Coumaroyl-CoA to naringenin chalcone. It is one of the essential enzymes in the anthocyanin pathway. The CHS needs a high amount of Malonyl-CoA to constantly perform the reaction. So it has to be noted, that if used in E. coli the source of Malonyl-CoA is limited.

Figure 1 Reaction of the CHS. 4-coumaroyl-CoA reacts together with 3 Malonyl-CoA to one naringenin chalcone.

Added by BIT-China_2020

Chalcone synthase (CHS) is a condensing enzyme, unique to plants, that builds a 15-carbon (C15) intermediate chalcone from which all flavonoids are derived. As the first enzyme committed to flavonoid production, it has often been referred to as the “key” enzyme of flavonoid biosynthesis. However, in some cases, the F’3H is of the same importance or even more.

Chalcone synthase catalyzes the formation of naringenin chalcone from one molecule of 4-coumaroyl CoA and three molecules of malonyl CoA .

Chalcone synthase functions as a homodimer, each polypeptide being approximately 41 kDa in size. The primary sequence of the CHS polypeptide is highly conserved between different plant species.

In nature, Three photoreceptors are involved in regulating flavonoid accumulation and CHS activity: a UV-B light receptor, a blue light receptor, and phytochrome.

This enzyme has got various most suitable PH when using different substrate. Generally, CHS shows high specificity for 4-coumaroyl CoA as a starter. As for the 4-coumaroyl-CoA ,the most suitable pH is 7.0. Besides, its different classifications react differently to the accumulation of flavonoids.[1]

References:

[1]Martin, C. R. (1993). Structure, Function, and Regulation of the Chalcone Synthase. International Review of Cytology, 233–284. doi:10.1016/s0074-7696(08)60770-6

Functional Parameters

The iGEM Team TU Darmstadt used the CHS and verified the function in their naringenin operon (BBa_K1497007).

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal NheI site found at 525
  
• 21
  INCOMPATIBLE WITH RFC[21]

  Illegal BglII site found at 534
  
• 23
  COMPATIBLE WITH RFC[23]
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal NgoMIV site found at 505
  Illegal NgoMIV site found at 1081
  
• 1000
  INCOMPATIBLE WITH RFC[1000]

  Illegal BsaI site found at 454