ArticleInfection and immunity1997
Generation of targeted nonpolar gene insertions and operon fusions in Pasteurella haemolytica and creation of a strain that produces and secretes inactive leukotoxin.
Article in Infection and immunity, 1997. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
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.
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.
Who cites it
15 citing papers in PubMed, 32 citations in OpenAlex.
- Article
- Gene expression profiling of bovine bronchial epithelial cells exposed in vitro to bovine herpesvirus 1 and Mannheimia haemolytica.Veterinary immunology and immunopathology · 2013Article
- Development of a double-crossover markerless gene deletion system in Bifidobacterium longum: functional analysis of the α-galactosidase gene for raffinose assimilation.Applied and environmental microbiology · 2012Article
- Mannheimia haemolytica and its leukotoxin cause macrophage extracellular trap formation by bovine macrophages.Infection and immunity · 2012Article
- Mannheimia haemolytica and its leukotoxin cause neutrophil extracellular trap formation by bovine neutrophils.Infection and immunity · 2010Article
- Gene replacement in mycobacteria by using incompatible plasmids.Applied and environmental microbiology · 2003Article
- Construction and characterization of an acapsular mutant of Mannheimia haemolytica A1.Infection and immunity · 2002Article
- Use of operon fusions in Mannheimia haemolytica to identify environmental and cis-acting regulators of leukotoxin transcription.Infection and immunity · 2001Article
- Analysis of the capsule biosynthetic locus of Mannheimia (Pasteurella) haemolytica A1 and proposal of a nomenclature system.Infection and immunity · 2001Article
- Inactivation of Pasteurella (Mannheimia) haemolytica leukotoxin causes partial attenuation of virulence in a calf challenge model.Infection and immunity · 2000Article
- Nonpolar inactivation of the hypervariable streptococcal inhibitor of complement gene (sic) in serotype M1 Streptococcus pyogenes significantly decreases mouse mucosal colonization.Infection and immunity · 2000Article
- Correlation of Pasteurella haemolytica leukotoxin binding with susceptibility to intoxication of lymphoid cells from various species.Infection and immunity · 1999Article
- Cloning and characterization of the gene encoding Pasteurella haemolytica FnrP, a regulator of the Escherichia coli silent hemolysin sheA.Journal of bacteriology · 1999Article
- Vaccination and protection of pigs against pleuropneumonia with a vaccine strain of Actinobacillus pleuropneumoniae produced by site-specific mutagenesis of the ApxII operon.Infection and immunity · 1999Article
- A putative leucine zipper activator of Pasteurella haemolytica leukotoxin transcription and the potential for modulation of its synthesis by slipped-strand mispairing.Infection and immunity · 1997Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
An efficient method for targeted gene inactivation and generation of chromosomal gene fusions in Pasteurella haemolytica has been devised and used to create an lktC::cat operon fusion by allelic exchange at the leukotoxin gene cluster (lktCABD). A copy of the lktC gene was insertionally inactivated by using a nonpolar, promoterless cat cassette and then delivered into P. haemolytica on a shuttle vector. Plasmid incompatibility was used to detect clones where double recombination events had occurred at the chromosomal locus. The insertion in lktC did not affect expression of the downstream genes, and the mutant strain secreted an antigenic proleukotoxin that was neither leukotoxic nor hemolytic. Expression of the lktC gene in trans restored the wild-type phenotype, confirming that LktC is required for activation of the proleukotoxin to the mature leukotoxin. Construction of the lktC::cat operon fusion allowed us to quantitate leukotoxin promoter activity in P. haemolytica and to demonstrate that transcription was maximal during early logarithmic growth phase but was reduced following entry into late logarithmic phase. This allelic exchange system should be useful for future genetic studies in P. haemolytica and could potentially be applied to other members of Haemophilus-Actinobacillus-Pasteurella family, where genetic manipulation is limited.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
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.