A jumping gene in Streptomyces coelicolor A3(2)
โ Scribed by Sermonti, Giuseppe ;Lanfaloni, Luisa ;Micheli, Maria Rita
- Publisher
- Springer
- Year
- 1980
- Tongue
- English
- Weight
- 454 KB
- Volume
- 177
- Category
- Article
- ISSN
- 0026-8925
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โฆ Synopsis
The difficulty in mapping the gene for chloramphenicol resistance (cmlR) in Streptomyces coelicolor A3(2) stock strains is possibly due to its location on different sites of the chromosome in various mixed subclones. Fresh isolates from CmlR strains show single unequivocal locations of cmlR. The same holds for CmlR strains derived as revertants from CmlS variants. The two best established sites for cmlR are one between cysA and metA, the other at right of argA, possibly in the right empty arc of the map (Fig. 2). The cmlR gene was assumed to be on a transposon (SCTn1), together with a gene for arginine-succinate synthase (argG), a gene for chromosome transfer (tra) and a gene for aereal mycelium formation (amy). In a CmlR revertant, the cmlR gene appears disjoined from argG (Fig. 5), thus showing the ability of SCTnl to be split and partially transposed. The possible wide occurrence of transposons in the genus Streptomyces is discussed.
๐ SIMILAR VOLUMES
Chloramphenicol resistance (Cmlr) of Streptomyces coelicolor A3(2) behaves like a transposon locus, not being localisable in any region of the map and yet being transferable in crosses at a rate comparable to that of chromosomal markers. It can also be transposed onto a plasmid (SCP1) and back to th
## Streptomyces coelicdor A3( 2 ) gives rise t o spontaneous chloramphenicol sensitive mutants a t a frequency of about 0.3% per spore. These mutants are often genetically unstable and give rise to arginine auxotrophs ( h g -) a t frequencies of 1-7% per spore. These Arg-mutants usually lack the