Possible Control of Formation of Aerial Mycelium and Antibiotic Production in Streptomyces by Episomic Factors

Okanishi, Masanori; Ohta, Toshiko; Umezawa, Hamao

doi:10.7164/antibiotics.23.45

Cited by 83 publications

(25 citation statements)

References 6 publications

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“…There have been a number of reports of the possible involvement of plasmid-borne genes in aerial mycelium development (Okanishi, Ohta & Umezawa, 1970;Kahler & Noack, 1974;Redshaw et aZ., 1976). However, all the bZd mutations mapped so far in S. coeZicoZor can be assigned unequivocally to map locations on the circular chromosome, although experiments using curing agents such as ethidium bromide have not been carried out.…”

Section: Discussionmentioning

confidence: 99%

A Morphological and Genetic Mapping Study of Bald Colony Mutants of Streptomyces coelicolor

Merrick¹

1976

Journal of General Microbiology

198

233

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S U M M A R YTwelve bld mutations of Streptomyces coelicolor resulting in a lack of visible aerial mycelium were mapped genetically. The mutants were classified into three groups on the basis of colony morphology, production of antibiotics and morphology on different carbon sources. Four map locations were found for the bld genes and three of these were very near the loci of whi genes, which are also involved in differentiation. Closely linked bld mutations had similar phenotypes.

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Section: Discussionmentioning

confidence: 99%

A Morphological and Genetic Mapping Study of Bald Colony Mutants of Streptomyces coelicolor

Merrick¹

1976

Journal of General Microbiology

198

233

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“…Single colonies were used to inoculate 25 ml medium B (Okanishi, Ohta & Umezawa, 1970) in 250 ml conical flasks, each containing a coiled stainless-steel spring to aid growth dispersal and aeration. The cultures were grown on an orbital shaker at 30 "C for 40 h. The mycelium was allowed to settle and 1.5 ml was cooled in ice and sonicated for 15 min (in 15 s bursts) at setting 3 on a Soniprobe with a microtip (type 753oA; Dawe Instruments, London).…”

Section: Isolation Of Chloramphenicol-sensitive Strains Streptomycesmentioning

confidence: 99%

Chloramphenicol Acetyltransferase-independent Chloramphenicol Resistance in Streptomyces coelicolor A3(2)

Freeman

Bibb

Hopwood

1977

Journal of General Microbiology

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SUMMARYStreptomyces coelicolor ~3 ( 2 ) and S. lividans 66, which lack chloramphenicol acetyltransferase, gave rise to chloramphenicol-sensitive (Cmls) variants spontaneously at frequencies of 0.5 to 2 %. The fertility type of S. coelicolor in respect of the SCPI plasmid (SCPI+, SCPI-or NF) had no effect on chloramphenicol sensitivity or on the frequency at which Cml' variants arose.Cmls isolates spontaneously reverted to Cml" at frequencies one to three orders of magnitude lower than the frequency with which CmlS strains arose from Cml". Cml" revertants obtained spontaneously from CmlS clones again produced Cmls isolates at the normal frequency of several per cent. Therefore, CmlS and CmlR are reversible phenotypes.

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“…8,[12][13][14][15][16][17][18][19][20] Treatment of streptomycetes with acridine dyes or at high temperature frequently causes loss of various phenotypic characters with coincidental disappearance of plasmids. In S. coelicolor A3(2), the direct involvement of plasmids in the production of methylenomycin A (SCP1 plasmid) 21,22) and streptocin A, B and amrumycin (SCP2 plasmid)23) has been confirmed.…”

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confidence: 99%

Mutants blocked in streptomycin production in Streptomyces griseus - the role of A-factor.

1982

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Ninety-five streptomycin-nonproducing mutants derived from Streptomyces griseus FT-1 by UV-irradiation could be classified into major two classes by cosynthesis tests. Class I mutants (42 strains) were mutants blocked in the pathway of streptomycin biosynthesis while class II mutants (49 strains) required a factor for streptomycin biosynthesis which was excreted by the parental or class I mutant strains. The factor could be replaced by synthetic A-factor (2S-isocapryloyl-3S-hydroxymethyl-r-butyrolactone) which restored both streptomycin biosynthesis and spore formation in the class II mutants. A-Factor deficient mutants were obtained from several strains of S. griseus and S. bikiniensis at high frequency by treatment with acridine orange or incubation at high temperature.A mutant whose streptomycin biosynthesis was independent of A-factor deficiency was found. The production of A-factor was distributed among various species of actinomycetes.

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Possible Control of Formation of Aerial Mycelium and Antibiotic Production in Streptomyces by Episomic Factors

Cited by 83 publications

References 6 publications

A Morphological and Genetic Mapping Study of Bald Colony Mutants of Streptomyces coelicolor

A Morphological and Genetic Mapping Study of Bald Colony Mutants of Streptomyces coelicolor

Chloramphenicol Acetyltransferase-independent Chloramphenicol Resistance in Streptomyces coelicolor A3(2)

Mutants blocked in streptomycin production in Streptomyces griseus - the role of A-factor.

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