The stabilizing effect of spermine and related polyamines and bacterial protoplasts

Mager, J.

doi:10.1016/0006-3002(59)90195-7

Cited by 105 publications

(49 citation statements)

References 6 publications

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“…Biosynthetic pathways for several polyamines, including putrescine and spermine, were also disrupted. This is consistent with the observations that F. tularensis is unable to survive under hypotonic conditions 21 and that osmotolerance can be attained by addition of micromolar amounts of putrescine and spermine 21 .…”

Section: Predicted Metabolic Pathways and Growth Requirementssupporting

confidence: 91%

The complete genome sequence of Francisella tularensis, the causative agent of tularemia

et al. 2005

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Francisella tularensis is one of the most infectious human pathogens known. In the past, both the former Soviet Union and the US had programs to develop weapons containing the bacterium. We report the complete genome sequence of a highly virulent isolate of F. tularensis (1,892,819 bp). The sequence uncovers previously uncharacterized genes encoding type IV pili, a surface polysaccharide and iron-acquisition systems. Several virulence-associated genes were located in a putative pathogenicity island, which was duplicated in the genome. More than 10% of the putative coding sequences contained insertion-deletion or substitution mutations and seemed to be deteriorating. The genome is rich in IS elements, including IS630 Tc-1 mariner family transposons, which are not expected in a prokaryote. We used a computational method for predicting metabolic pathways and found an unexpectedly high proportion of disrupted pathways, explaining the fastidious nutritional requirements of the bacterium. The loss of biosynthetic pathways indicates that F. tularensis is an obligate host-dependent bacterium in its natural life cycle. Our results have implications for our understanding of how highly virulent human pathogens evolve and will expedite strategies to combat them.

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Section: Predicted Metabolic Pathways and Growth Requirementssupporting

confidence: 91%

The complete genome sequence of Francisella tularensis, the causative agent of tularemia

et al. 2005

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“…Mitochondria ( 15) bacteriophages ( 1,13,16) and bacterial protoplasts (11,12,15) are damaged in the al)sence of cations, and protected from damage when cations are present. In these other systems monovalent ions (lo not seem to be effective, and often spermine and sperimidine are unusually effective protective agents.…”

Section: Resultsmentioning

confidence: 99%

Uncoupling Phosphorylation in Spinach Chloroplasts by Absence of Cations

Jagendorf

Smith²

1962

Plant Physiol.

120

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During attempts to prepare active fragments of spinach chloroplasts, we observed major losses of phosphorylative activity following suspension of the chloroplasts in water. This damage was traced to treatments which probably had the effect of removing cations from the chloroplasts, rather than to a simple physical disruption. Indeed, chloroplast fragments have been used successfully in studies of phosphorylation for a considerable time by now (3,18). Evi. dence for the basis of the observed damage and characteristics of the inactivated chloroplasts will be described below. Materials & Methods

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“…The only chemical tested which effectively caused release of the enzyme was the basic polyamine spermine which has strong affinity for electronegative structures, e.g. cell membranes (Mager, 1959). Spermine therefore probably released the enzyme by displacing it from its attachment to electronegative groups on or within the core.…”

Section: Discussionmentioning

confidence: 99%

Function and Location of a "Germination Enzyme" in Spores of Bacillus Cereus

Gould

Hitchins

King

1966

Journal of General Microbiology

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SUMMARYAn enzyme extracted from Bacillus cereus spores caused to germinate spores of this organism which had been sensitized by reagents which rupture disulphide bonds. Inactivation of the enzyme by thiol-blocking agents and by oxidation, and reactivation by reduction suggested that the enzyme's ability to germinate spores depended on thiol groups. No evidence was obtained to support the hypothesis that the enzyme was present in dormant spores in the oxidized inactive form and became reduced and active during germination. When spores were disrupted at pH 3 the enzyme was found to be bound to debris; probably on or within the central core of the spore. At pH 5.8 or below the enzyme remained bound to the debris, but a t pH 7.0 the enzyme was irreversibly released when the ionic strength of the medium was high. I n solutions of sodium phosphate less than 0.05 M, the enzyme remained mostly bound even at pH 7-0. It was largely released when the concentration of sodium phosphate was increased to 0.2 M. Extracts of germinated spores contained more unbound and less bound enzyme than extracts of ungerminated spores, suggesting that release of enzyme from a bound form occurred during germination of the spores.

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The stabilizing effect of spermine and related polyamines and bacterial protoplasts

Cited by 105 publications

References 6 publications

The complete genome sequence of Francisella tularensis, the causative agent of tularemia

The complete genome sequence of Francisella tularensis, the causative agent of tularemia

Uncoupling Phosphorylation in Spinach Chloroplasts by Absence of Cations

Function and Location of a "Germination Enzyme" in Spores of Bacillus Cereus

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