Streptomyces lividans 66 produced spontaneous chloramphenicol-sensitive mutants (CmlS) at a frequency of about 1% of spores. The CmlS mutant strains were very unstable, giving Arg- mutants at frequencies of about 25% of spores. All the Arg- mutants had amplified a particular 5.75 kb DNA fragment int
Structure of an amplifiable DNA sequence in Streptomyces lividans 66
โ Scribed by Altenbuchner, Josef ;Cullum, John
- Publisher
- Springer
- Year
- 1985
- Tongue
- English
- Weight
- 938 KB
- Volume
- 201
- Category
- Article
- ISSN
- 0026-8925
No coin nor oath required. For personal study only.
โฆ Synopsis
Spontaneous chloramphenicol-sensitive mutants of Streptomyces lividans 66 had previously been shown to be very unstable and to yield arginine auxotrophic mutants at a frequency of 25% of spores; the Arg-mutants had amplified a particular 5.7 kb DNA sequence to over one hundred tandem copies per genome. In this paper we report the cloning of the amplifiable region from amplified and wild-type strains. This showed that the amplifiable fragment is already present as a duplication in wild type cells. Hybridisation experiments also demonstrated that in the amplified strains there was a deletion of neighbouring DNA sequences to one side of the amplifiable element; sequences to the other side remain intact.
๐ SIMILAR VOLUMES
A mutant of Streptomyces coelicolor A 3(2) highly resistant to chloramphenicol was selected. It had amplified some chromosomal DNA fragments to a copy number of 20-50. Some of the amplified fragments were cloned and used as hybridisation probes to investigate the spontaneous chloramphenicol-sensitiv
The amplifiable AUD1 element of Streptomyces lividans 66 consists of two copies of a 4.7 kb sequence flanked by three copies of a 1 kb sequence. The DNA sequences of the three 1 kb repeats were determined. Two copies (left and middle repeats) were identical: (1009 bp in length) and the right repeat
## Abstract Recent studies of the structure of messenger RNA have demonstrated the existence of untranslated sequences of the 3โฒ and 5โฒ end of the messages. In addition analysis of transcription in vitro has indicated that the nucleotide sequence U6 purine may be part of a transcription termination
Abstract The partial sequence (600 bp) containing the most variable region of Vibrio vulnificus 16S ribosomal DNA (rDNA) was determined for 208 randomly selected V. vulnificus strains isolated from Galveston Bay, TX, USA between June 2000 and June 2001. A comparative analysis of the determined parti