Difference between revisions of "Part:BBa K1471002"

Revision as of 05:34, 16 October 2014

RBS with MerE.

This part contains a RBS for A. thaliana followed by a coding sequence named MerE from the bacterial operon mer. We did codon optimization of MerE gene, for it's expression in Arabidopsis thaliana.

Brief description merE Our part is a yeast RBS with an 8KDa CH3Hg or Hg+2 transmembrane bacterial transporter.

Biology

MerE is a gene is part of the mer operon, a collection of bacterial genes specialized on the tolerance to various compounds of mercury including methylmercury. It is naturally found in the transposon Tn21 from the plasmid NR1 Shigella flexneri or MB1 in the case of Bacillus megaterium. The general mechanism of the operon can be observed on the following representation (Das S., Dash H. R., 2012):

Schematic presentation of mer operon in narrow-spectrum Gram-negative mercury-resistant bacteria (Das S., Dash H. R., 2012)

Where organomercury compounds are transported inside the bacteria by merP, merT, mer E and merG, followed by the transformation of organic mercury by merB into its ionic form and the reduction from Hg+2 into volatile Hg0 by mer A with the help of NADPH(Das S., Dash H. R., 2012).

Although the transportation of methylmercury is barely understood, there is evidence that recombinant E. coli and other transformed GRAM negative bacteria are able to accumulate mercury thanks to the transformation of organic mercury into its ionic form(Das S., Dash H. R., 2012).

Behaviour merE has been characterized previously on A. thaliana as a potential mercury accumulator and transporter. In Kyono,M., et al (2013)´s study shoot and root growth were observed to become more tolerant in transgenic Arabidopsis compared with controls. As it can be seen on the figure:

Susceptibility of transgenic plants to Hg(II) and CH3Hg(I). (Kiyono M. , et al, 2013)

Sequence and Features