Evaluation of Live Tularemia Vaccine Prepared in a Chemically Defined Medium

Chamberlain, R. E.

doi:10.1128/aem.13.2.232-235.1965

Cited by 192 publications

(114 citation statements)

References 5 publications

Supporting

Mentioning

113

Contrasting

Unclassified

Order By: Relevance

“…Bacterial strains were grown overnight from frozen stocks at 37°C in chemically defined PN or Chamberlain's media. Cultures were then diluted 1:100 in 20 ml fresh PN/Chamberlain's media (Chamberlain, 1965) and allowed to grow to a cell density of~1.0 ¥ 10 9 cfu ml -1 . Cultures were centrifuged, washed and resuspended in 1 ml of PBS.…”

Section: High-performance Liquid Chromatography (Hplc) Analysis Of Pomentioning

confidence: 99%

Arginine catabolic mobile element encoded speG abrogates the unique hypersensitivity of Staphylococcus aureus to exogenous polyamines

Joshi

Spontak

Klapper

et al. 2011

Molecular Microbiology

141

159

View full text Add to dashboard Cite

Polyamines, including spermine (Spm) and spermidine (Spd), are aliphatic cations that are reportedly synthesized by all living organisms. They exert pleiotropic effects on cells and are required for efficient nucleic acid and protein synthesis. Here, we report that the human pathogen Staphylococcus aureus lacks identifiable polyamine biosynthetic genes, and consequently produces no Spm/Spd or their precursor compounds putrescine and agmatine. Moreover, while supplementing defined medium with polyamines generally enhances bacterial growth, Spm and Spd exert bactericidal effects on S. aureus at physiologic concentrations. Small colony variants specifically lacking menaquinone biosynthesis arose after prolonged Spm exposure and exhibited reduced polyamine-sensitivity. However, other respiratory-defective mutants were no less susceptible to Spm implying menaquinone itself rather than general respiration is required for full Spm-toxicity. Polyamine hypersensitivity distinguishes S. aureus from other bacteria and is exhibited by all tested strains save those belonging to the USA-300 group of Community-Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA). We identified one gene within the USA-300-specific Arginine Catabolic Mobile Element (ACME) encoding a Spm/Spd N-acetyltransferase that is necessary and sufficient for polyamine resistance. S. aureus encounters significant polyamine levels during infection, however the acquisition of ACME encoded speG allows USA-300 clones to circumvent polyamine-hypersensitivity, a peculiar trait of S. aureus.

show abstract

Section: High-performance Liquid Chromatography (Hplc) Analysis Of Pomentioning

confidence: 99%

Arginine catabolic mobile element encoded speG abrogates the unique hypersensitivity of Staphylococcus aureus to exogenous polyamines

Joshi

Spontak

Klapper

et al. 2011

Molecular Microbiology

141

159

View full text Add to dashboard Cite

show abstract

“…The Francisella, Escherichia coli and Pseudomonas strains used in this study are listed in Table 2. F. tularensis strains were grown on modified Thayer-Martin agar plates (Sandström et al, 1984) at 37°C in 5% CO 2 atmosphere or in Chamberlain medium (Chamberlain, 1965). E. coli and P. aeruginosa strains were grown on blood agar base (BAB; Merck) plates, on minimal medium plates (Vogel and Bonner, 1956) or in Luria-Bertani broth (LB).…”

Section: Bacterial Strains Plasmids Mammalian Cells and Growth Condmentioning

confidence: 99%

Direct repeat‐mediated deletion of a type IV pilin gene results in major virulence attenuation of Francisella tularensis

Forslund¹,

Kuoppa²,

Svensson

et al. 2006

Molecular Microbiology

142

View full text Add to dashboard Cite

SummaryFrancisella tularensis , the causative agent of tularaemia, is a highly infectious and virulent intracellular pathogen. There are two main human pathogenic subspecies, Francisella tularensis ssp. tularensis (type A), and Francisella tularensis ssp. holarctica (type B). So far, knowledge regarding key virulence determinants is limited but it is clear that intracellular survival and multiplication is one major virulence strategy of Francisella . In addition, genome sequencing has revealed the presence of genes encoding type IV pili (Tfp). One genomic region encoding three proteins with signatures typical for type IV pilins contained two 120 bp direct repeats. Here we establish that repeat-mediated loss of one of the putative pilin genes in a type B strain results in severe virulence attenuation in mice infected by subcutaneous route. Complementation of the mutant by introduction of the pilin gene in cis resulted in complete restoration of virulence. The level of attenuation was similar to that of the live vaccine strain and this strain was also found to lack the pilin gene as result of a similar deletion event mediated by the direct repeats. Presence of the pilin had no major effect on the ability to interact, survive and multiply inside macrophage-like cell lines. Importantly, the pilinnegative strain was impaired in its ability to spread from the initial site of infection to the spleen. Our findings indicate that this putative pilin is critical for Francisella infections that occur via peripheral routes.

show abstract

“…DNA was introduced into F. novicida U112 and mutant strains exclusively by chemical transformation as described previously (Anthony et al, 1991), with the following modification. Efficient chemical transformation of F. novicida normally requires the use of a complex synthetic medium, Chamberlain's broth (Chamberlain, 1965). In this work it was found that the simple addition of 0.4% glucose rendered fresh TSB equally suitable as a transformation medium.…”

Section: Transformation and Conjugationmentioning

confidence: 93%

Genetic elements for selection, deletion mutagenesis and complementation inFrancisellaspp.

Ludu

Nix

Duplantis

et al. 2008

FEMS Microbiology Letters

View full text Add to dashboard Cite

Francisella novicida is a gram-negative pathogen that can induce disease in mice that mimics human tularemia, and is nearly identical to Francisella tularensis at the genomic level. In this work a number of antibiotic marker cassettes that incorporate a strong F. novicida promoter is constructed, which greatly enhances selection in F. novicida and F. tularensis. Two low-copy plasmid vectors based on a broad-host-range plasmid, and an integrating vector have also been made, and these can be used for genetic complementation. Two general approaches to deletion mutagenesis in F. novicida is also described.

show abstract

Evaluation of Live Tularemia Vaccine Prepared in a Chemically Defined Medium

Cited by 192 publications

References 5 publications

Arginine catabolic mobile element encoded speG abrogates the unique hypersensitivity of Staphylococcus aureus to exogenous polyamines

Arginine catabolic mobile element encoded speG abrogates the unique hypersensitivity of Staphylococcus aureus to exogenous polyamines

Direct repeat‐mediated deletion of a type IV pilin gene results in major virulence attenuation of Francisella tularensis

Genetic elements for selection, deletion mutagenesis and complementation inFrancisellaspp.

Contact Info

Product

Resources

About