Related Experiment Videos
Giant linear plasmids in Streptomyces which code for antibiotic biosynthesis genes
Nature
|July 5, 1987
Summary
Researchers identified large linear plasmids in Streptomyces using advanced gel electrophoresis. These giant plasmids carry antibiotic synthesis genes, explaining genetic variability in these bacteria.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Circular plasmids are common, but large linear plasmids are difficult to isolate and study.
- Previous genetic evidence suggested plasmids encode antibiotic synthesis in Streptomyces, but none were detected.
- The plasmid SCP1 in Streptomyces coelicolor is implicated in methylenomycin production.
Purpose of the Study:
- To develop a method for isolating large linear plasmids from Streptomyces.
- To physically identify and characterize these plasmids.
- To confirm the location of antibiotic biosynthesis genes on these plasmids.
Main Methods:
- Application of orthogonal-field-alternation gel electrophoresis (OFAGE).
- Isolation and characterization of large linear plasmids from Streptomyces species.
- Genetic analysis to confirm gene location.
Main Results:
- Successfully isolated large linear plasmids from Streptomyces using OFAGE.
- Discovered a giant linear plasmid of approximately 520 kilobases in Streptomyces lasaliensis.
- Confirmed that methylenomycin biosynthesis genes are located on giant linear plasmids in Streptomyces coelicolor.
Conclusions:
- Giant linear plasmids exist in Streptomyces and can be isolated using OFAGE.
- These plasmids carry essential genes for antibiotic synthesis.
- The presence of these plasmids may explain the genetic variability and instability observed in Streptomyces species.