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Published on: October 14, 2011
Properties of Streptomyces phage SLE111
Zeitschrift Fur Allgemeine Mikrobiologie
|January 1, 1984
Summary
Phage SLE111 infecting Streptomyces levoris exhibits unique morphology and high lytic yield. Its double-stranded DNA genome lacks cohesive ends and terminal redundancy, featuring a distinct stem-loop structure.
Area of Science:
- Microbiology
- Molecular Biology
- Virology
Background:
- Actinophages are viruses that infect actinobacteria, crucial in various environments.
- Understanding phage diversity and genomic features is vital for their application in biotechnology and therapy.
- Phage SLE111 infecting Streptomyces levoris presents distinct characteristics compared to previously described actinophages.
Purpose of the Study:
- To characterize the morphology and genomic properties of phage SLE111.
- To investigate the lytic potential and growth characteristics of phage SLE111.
- To analyze the DNA structure, including end configurations and potential secondary structures.
Main Methods:
- Phase contrast microscopy and electron microscopy of ultrathin sections to observe morphological changes.
- Electron microscopy for detailed analysis of the phage's double-stranded DNA genome.
- Characterization of DNA features such as cohesive ends, terminal redundancy, and circular permutation.
Main Results:
- Phage SLE111 demonstrated a unique morphology compared to other actinophages.
- High titres of phage SLE111 (10(11) p.f.u/ml) were achieved after lytic growth.
- The SLE111 genome is a linear, double-stranded DNA (44.2 ± 1.3 kb) lacking cohesive ends, terminal redundancy, and circular permutation.
- A stem-loop structure with inverted repeats (approx. 200 bp) was identified in two positions within the genome.
Conclusions:
- Phage SLE111 is a morphologically distinct actinophage with significant lytic activity.
- Its linear dsDNA genome possesses unique structural features, including the absence of typical end modifications and the presence of a specific stem-loop structure.
- These findings contribute to the understanding of actinophage diversity and genome organization.
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