Coding

Part:BBa_K1420001

Designed by: Stephen C. Heinsch   Group: iGEM14_Minnesota   (2014-09-26)
Revision as of 22:21, 12 October 2014 by Skog0122 (Talk | contribs) (Function)

merA, mercuric reductase from Serratia marcescens

Overview

MerA, a cytoplasmic mercuric ion reductase, is the essential component of bacterial mercury resistance. Both MerA and the organomercurial lyase, MerB, work together to reduce the toxicity of inorganic and organic mercury compounds. While MerA and MerB are the key mercury detoxification enzymes, they orchestrate with mercury transport proteins, MerT and MerP, to confer bacterial mercury resistance.

Figure 1 shows the interactions of MerA, mercury compounds, and other mer proteins. MerA and gene merA are highlighted in orange.merA is located downstream of mer genes that encodes mercury transport proteins.

MerA.jpg

This figure is adapted from "Bacterial mercury resistance from atoms to ecosystems". Reference: T. Barkay et al. FEMS Microbiology Reviews 27 (2003) 355-384.

Molecular Function

MerA catalyzes the reduction of mercuric ion to the relative inert, volatile monoatomic mercury in a NADPH dependent reaction.

Scheme 1. MerA Catalyzed Reaction

MerAReactionmechanism.jpg

Structure and Mechanism

Characterization of merA

To test the effect of MerA to the level of mercury resistance, we generated a merA deletion mutant and characterized it by zone of inhibition test.

Zone of Inhibition Results

alt text

Figure 2. Zones of Inhibition Test For Mercury Resistance Activity. Three different plasmids were expressed in Escherichia coli strain K12 to compare level of mercury resistance. (A)Plates of ZOI test. Left, K12 conntaining pBBRBB::mer; center,K12 containing pBBRBB::gfp; right, K12 strain containing pBBRBB::merΔmerA, or the merA deletion mutant. (b) Graphical representation of the size of zones of inhibition diameter. The diameter of the Zone of Inhibition was measured in triplicate. Green corresponds to pBBRBB::gfp, blue to pBBRBB::mer, and red to pBBRBB::merΔmerA.

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 1201
    Illegal NgoMIV site found at 1249
    Illegal NgoMIV site found at 1311
    Illegal NgoMIV site found at 1522
  • 1000
    COMPATIBLE WITH RFC[1000]


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Categories
//binding/metal
//cds
Parameters
None