Evidence map›Paper›PMID 18606801›Full record

ArticleApplied and environmental microbiology2008

Broad-host-range expression vectors with tightly regulated promoters and their use to examine the influence of TraR and TraM expression on Ti plasmid quorum sensing.

Sharik R Khan, Jennifer Gaines, R Martin Roop, Stephen K Farrand

Abstract read
In one paragraph

Article in Applied and environmental microbiology, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 213 papers.

0numbers the graph read from it
0cells of the map it votes in
213citing papers in PubMed
3.4field-weighted citation impact, top 7% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

213 citing papers in PubMed, 343 citations in OpenAlex.

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153 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors at 2 institutions in 1 country.

Sharik R KhanDepartment of Microbiology, University of Illinois at Urbana-Champaign, B103 Chemical and Life Sciences Laboratory, 601 South Goodwin Avenue, Urbana, IL 61801, USA.
Jennifer Gaines
R Martin Roop
Stephen K Farrand
East Carolina University · USUniversity of Illinois Urbana-Champaign · US

Funding

BRUCELLA STATIONARY PHASE GENE EXPRESSION AND VIRULENCER01AI048499 · NIAID · LOUISIANA STATE UNIV HSC SHREVEPORT · PI ROOP, ROY M · 2000 to 2010
$2.8M
CELL-CELL SIGNALLING IN MICROBE-HOST INTERACTIONSR01GM052465 · NIGMS · UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN · PI FARRAND, STEPHEN KENDALL · 1995 to 2007
$2.6M
NIAID NIH HHS R01 AI048499NIAID NIH HHS R01 AI48499NIGMS NIH HHS R01 GM052465NIGMS NIH HHS R01 GM52465
6 · The paper itself

Abstract

Experiments requiring strong repression and precise control of cloned genes can be difficult to conduct because of the relatively high basal level of expression of currently employed promoters. We report the construction of a family of vectors that contain a reengineered lacI(q)-lac promoter-operator complex in which cloned genes are strongly repressed in the absence of inducer. The vectors, all based on the broad-host-range plasmid pBBR1, are mobilizable and stably replicate at moderate copy number in representatives of the alpha- and gammaproteobacteria. Each vector contains a versatile multiple cloning site that includes an NdeI site allowing fusion of the cloned gene to the initiation codon of lacZalpha. In each tested bacterium, a uidA reporter fused to the promoter was not expressed at a detectable level in the absence of induction but was inducible by 10- to 100-fold, depending on the bacterium. The degree of induction was controllable by varying the concentration of inducer. When the vector was tested in Agrobacterium tumefaciens, a cloned copy of the traR gene, the product of which is needed at only a few copies per cell, did not confer activity under noninducing conditions. We used this attribute of very tight and variably regulatable control to assess the relative amounts of TraR required to activate the Ti plasmid conjugative transfer system. We identified levels of induction that gave wild-type transfer frequencies, as well as levels that induced correspondingly lower frequencies of transfer. We also used this system to show that the antiactivator TraM sets the level of intracellular TraR required for tra gene activation.

Indexed as

Gene Expression Regulation, BacterialQuorum SensingAgrobacterium tumefaciensBacterial ProteinsCloning, MolecularConjugation, GeneticGenetic EngineeringGenetic VectorsPlant Tumor-Inducing PlasmidsPromoter Regions, GeneticTranscriptional ActivationBacterial ProteinsTraM protein, bacterialTraR protein, Agrobacterium tumefaciens

Identifiers

PMID18606801
PMCPMC2519271
OpenAlexW2160947128

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.