Difference between revisions of "Part:BBa K525551"

Revision as of 21:07, 21 September 2011

NADP+ Oxidoreductase and polycistronic BisdA and BisdB

Ferredoxin-NADP⁺ oxidoreductase and polycistronic bisdA and bisdB for characterization of intracellular bisphenol A degradation with E. coli.

Usage and Biology

Expressing this BioBrick in E. coli enables the bacterium to degrade the endocrine disruptor bisphenol A (BPA). The fusion protein works better than a polycistronic expression of the two BioBricks bisdA (BBa_K123000) and bisdB (BBa_K123001).

BPA is mainly hydroxylated into the products 1,2-Bis(4-hydroxyphenyl)-2-propanol and 2,2-Bis(4-hydroxyphenyl)-1-propanol. In S. bisphenolicum AO1, a total of three genes are responsible for this BPA hydroxylation: a cytochrome P450 (CYP, bisdB), a ferredoxin (Fd, bisdA) and a ferredoxin-NAD⁺ oxidoreductase (FNR) Sasaki05a. The three gene products act together to reduce BPA while oxidizing NADH + H⁺. The cytochrome P450 (BisdB) reduces the BPA and is oxidized during this reaction. BisdB in its oxidized status is reduced by the ferredoxin (BisdA) so it can reduce BPA again. The oxidized BisdA is reduced by a ferredoxin-NAD⁺ oxidoreductase consuming NADH + H⁺ so the BPA degradation can continue Sasaki05a. This electron transport chain between the three enzymes involved in BPA degradation and the BioBricks needed to enable this reaction in vivo and in vitro are shown in the following figure (please have some patience, it's an animated .gif file):

Fig. 1: Animation of proposed reaction mechanism of bisphenol A hydroxylation by the involved enzymes FNR (BBa_K525499), Fd (BisdA, BBa_K123000) and CYP (BisdB, BBa_K123001)

Sequence and Features