Nucleotide sequence and expression of the organomercurial-resistance determinants from a Pseudomonas K-62 plasmid pMR26

Kiyono, Masako; Omura, Tomoko; Inuzuka, Manabu; Fujimori, Hiroyuki; Pan-Hou, Hidemitsu

doi:10.1016/s0378-1119(96)00741-x

Cited by 44 publications

(36 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At a minimum, these mer operons contain mercuric reductase (MerA) for reducing reactive inorganic Hg(II) to volatile, relatively inert monoatomic Hg(0) vapor, a periplasmic Hg(II)-binding protein (MerP) and an inner membrane Hg(II) transport protein (MerT), which are under control of the metal-responsive positive or negative regulators MerR or MerD, respectively. [1][2][3][4] In Gram-negative bacteria, merE is located at the end of the operon immediately following merD, and merE is also frequently found in Gram-positive mer operons. 1,3) Gram-negative bacteria encode a MerE polypeptide of 78 aa (8.0 kDa), which is predicted to form two transmembrane-spanning α-helices with a cysteine pair positioned in approximately the middle of the first helix.…”

Section: Introductionmentioning

confidence: 99%

Roles Played by MerE and MerT in the Transport of Inorganic and Organic Mercury Compounds in Gram-negative Bacteria

Sone

Pan-Hou

Nakamura

et al. 2010

JOURNAL OF HEALTH SCIENCE

Self Cite

View full text Add to dashboard Cite

In order to clarify the physiological roles played by MerP, MerT and MerE in Gram-negative bacteria, we constructed the plasmids pTP4 and pTPE21, which contained the genes merR, merT and merP, from the Pseudomonas K-62 plasmid pMR26, or the same genes with the merE gene of Tn21 from the Shigella flexneri plasmid NR1 (R100), respectively. Cells containing pTP4 showed increased hypersensitivity to Hg(II), but maintained a normal sensitivity to CH 3 Hg(I). However, cells with pTPE21 exhibited increased hypersensitivity to Hg(II) and CH 3 Hg(I). Cells with pTP4 accumulated appreciably more Hg(II) than control cells, but no significant difference was observed in their uptake of 14 CH 3 Hg(I). In contrast, the cells containing pTPE21 accumulated significantly larger amounts of Hg(II) and 14 CH 3 Hg(I) than either control cells or cells with pTP4. These results suggest that the mer operons have evolved to redirect uptake of mercurials into dedicated, specific and relatively high-affinity transport systems comprising the small periplasmic protein MerP and two inner membrane proteins, MerT and MerE.

show abstract

Section: Introductionmentioning

confidence: 99%

Roles Played by MerE and MerT in the Transport of Inorganic and Organic Mercury Compounds in Gram-negative Bacteria

Sone

Pan-Hou

Nakamura

et al. 2010

JOURNAL OF HEALTH SCIENCE

Self Cite

View full text Add to dashboard Cite

show abstract

“…The high specificity is thought to be due to the highly specialized and selective genetic pMR26's merR, a narrow spectrum regulator that has been shown to rigidly respond to Hg 2+ but not to organomercury. 9,17) The biosensor also did not respond to bio-stable mercury such as metallic mercury and mercuric sulfide (Data not shown). Therefore, the mer-lux biosensor developed in this study is restricted for detection of bio-affecting Hg 2+ .…”

Section: Resultsmentioning

confidence: 94%

“…In the present study, a new biosensor plasmid pMQT which contains merR, mer o/p, and merT from pMR26 of Pseudomonas K-62 strain 9) and a promoterless luxAB gene from Vibrio harveyi 10) for detection of low concentrations of mercury was constructed ( Fig. 1).…”

Section: Resultsmentioning

confidence: 99%

Development of a Specific and Sensitive Bacteria Sensor for Detection of Mercury at Picomolar Levels in Environment

Omura

Kiyono

Pan-Hou

2004

JOURNAL OF HEALTH SCIENCE

Self Cite

View full text Add to dashboard Cite

“…Preparation of Specific Antibodies Plasmid pMRD141, 8) which contained merR-o/p-merT-merP from pMR26, was used as the template for the PCR amplification of a 0.3 kb XbaI-BglII fragment containing merP. The primers used were UP1117Xba (5′-GCT CTA GAT TCC ATT TTT CTA TTA-3′) and LP1412Bgl (5′-GAA GAT CTC TTC TTC AGC TCA GAT-3′), which contained restriction sites for XbaI and BglII, respectively.…”

Section: Computer Analyses Of Protein Sequencesmentioning

confidence: 99%

“…[4][5][6][7][8][9][10][11] These proteins have two, three, or four transmembrane domains (TMD), but TMD I and II are found in all members of the superfamily. 12) In all these proteins, one pair of cysteine residues is predicted to reside within the inner membrane, with or without a second pair of cysteine residues on the cytoplasmic face.…”

mentioning

confidence: 99%

Role of MerC, MerE, MerF, MerT, and/or MerP in Resistance to Mercurials and the Transport of Mercurials in <i>Escherichia coli</i>

Sone

Nakamura

Pan-Hou

et al. 2013

Biological & Pharmaceutical Bulletin

Self Cite

View full text Add to dashboard Cite

The characteristics of bacteria take up mercury into cells via membrane potential-dependent sequencedivergent members of the mercuric ion (Mer) superfamily, i.e., a periplasmic mercuric ion scavenging protein (MerP) and one or more inner membrane-spanning proteins (MerC, MerE, MerF, and MerT), which transport mercuric ions into the cytoplasm, have been applied in engineering of bioreactor used for mercurial bioremediation. We engineered bacteria to express MerC, MerE, MerF, or MerT with or without MerP to clarify their individual role and potential in transport of mercurial. By immunoblot analysis using specific polyclonal antibody, the proteins encoded by merC, merE, merF, merT or merP, were certainly expressed and identified in the membrane fraction. Bacteria expressing MerC, MerE, MerF or MerT in the absence of MerP transported significantly more C 6 H 5 Hg(I) and Hg(II) across bacterial membrane than their isogenic strain. In vivo expression of MerP in the presence of all the transporters did not cause apparent difference to the C 6 H 5 Hg(I) transport, but gives an apparently higher Hg(II) transport than that did by MerE, MerF or MerT but not by MerC. Among the four transporters studied, MerC showed more potential to transport Hg(II) across bacterial membrane than MerE, MerF and MerT. Together these findings, we demonstrated for the first time that in addition to MerE and MerT, MerF and MerC are broad-spectrum mercury transporters that mediate both Hg(II) and phenylmercury transport into cells. Our results suggested that MerC is the most efficient tool for designing mercurial bioremediation systems, because MerC is sufficient for mercurial transport into cells.

show abstract

Nucleotide sequence and expression of the organomercurial-resistance determinants from a Pseudomonas K-62 plasmid pMR26

Cited by 44 publications

References 24 publications

Roles Played by MerE and MerT in the Transport of Inorganic and Organic Mercury Compounds in Gram-negative Bacteria

Roles Played by MerE and MerT in the Transport of Inorganic and Organic Mercury Compounds in Gram-negative Bacteria

Development of a Specific and Sensitive Bacteria Sensor for Detection of Mercury at Picomolar Levels in Environment

Role of MerC, MerE, MerF, MerT, and/or MerP in Resistance to Mercurials and the Transport of Mercurials in <i>Escherichia coli</i>

Contact Info

Product

Resources

About