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In the presence of polyvalent cations, long double-stranded DNA (dsDNA) in dilute solution undergoes a single- molecule, first-order, phase transition (‘‘condensation’’), a phenomenon that has been documented and analyzed by many years of experimental and theoretical studies. There has been no systematic effort, however, to determine whether long single- stranded RNA (ssRNA) shows an analogous behavior. In this study, using dynamic light scattering, analytical ultracentrifugation, and gel electrophoresis, we examine the effects of increasing polyvalent cation concentrations on the effective size of long ssRNAs ranging from 3000 to 12,000 nucleotides. Our results indicate that ssRNA does not undergo a discontinuous conden- sation as does dsDNA but rather a ‘‘continuous’’ decrease in size with increasing polyvalent cation concentration. And, instead of the 10-fold decrease in size shown by long dsDNA, we document a 50% decrease, as demonstrated for a range of lengths and sequences of ssRNA.
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This content will become publicly available on March 1, 2026
Characterization of a novel broad-host-range polyvalent Tequatrovirus bacteriophage infecting Salmonella, Shigella, and Escherichia coli
We isolated and characterized the novel polyvalent T-even type bacteriophage vB_SenS_Jbel from wastewater using an enrichment of three different Salmonella strains. The vB_SenS_Jbel virions have prolate icosahedral capsids approximately 100 nm long and 80 nm wide. The genome consists of linear, double-stranded DNA that is 165,566 bp long. Analysis of the genome and structure of vB_SenS_Jbel indicates that it belongs to the genus Tequatrovirus of the family Straboviridae. This novel polyvalent phage can infect Escherichia coli and multiple Salmonella and Shigella species through its unique tail fiber structure.
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- Award ID(s):
- 2228971
- PAR ID:
- 10630175
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Archives of Virology
- Volume:
- 170
- Issue:
- 3
- ISSN:
- 0304-8608
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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