ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Genetic recombination and strain improvement, (Volume 18) (1999)
    Springer
    Journal of industrial microbiology and biotechnology 22 (1999), S. 323-335 
    Details
    ISSN: 1476-5535
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/sj.jim.2900646
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Analysis of secondary, integration sites for IS117 in Streptomyces lividans and their role in the generation of chromosomal deletions (1993)
    Springer
    Molecular genetics and genomics 239 (1993), S. 90-96 
    Details
    ISSN: 1617-4623
    Keywords: Transposable element ; Site-specific integration ; DNA rearrangement ; Deletion formation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract IS117, the 2.6 kb mini-circle of Streptomyces coelicolor A3(2), is a transposable element previously shown to be integrated into two distant sites in the chromosome. When introduced into S. lividans, IS117 integrates into one preferred chromosomal site, but when this site was artificially deleted, IS117 integrated into many secondary sites. Nucleotide sequence analysis of several secondary integration sites revealed varying degrees of similarity with the preferred site, but no consensus sequence. Nevertheless, sites more similar to the preferred site tended to be occupied more often than those that are less similar. Insertion of IS117 into secondary sites in the chromosome of S. lividans sometimes mediated chromosomal rearrangements. It was shown that some strains containing IS117 integrated into secondary sites had suffered deletions of chromosomal DNA. Deletions were adjacent to the inserted element and were at least several kilobases long. The proposed model implicates homologous recombination between IS117 copies integrated into two different secondary sites in the same chromosome as a cause of the deletions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00281606
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Bacterial protoplast fusion: Recombination in fused protoplasts of Streptomyces coelicolor (1978)
    Springer
    Molecular genetics and genomics 162 (1978), S. 307-317 
    Details
    ISSN: 1617-4623
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Numerous recombinants arose when protoplasts of S. coelicolor were treated with polyethylene glycol and regenerated on non-selective solid medium. In six-factor crosses, recombination frequencies of more than 10% (up to 17%) were routinely observed. This recombination did not require either of the known sex factors, SCP1 and SCP2. The proportion of multiple crossover classes was much higher than amongst recombinants produced by conjugation between mycelia. Analysis of the spatial distribution of crossovers in double and quadruple crossover recombinants showed only a slight tendency for crossovers to occur closer together than randomly on the complete linkage group. This suggests that genomes brought together by protoplast fusion are complete, or nearly so (in conjugation, in contrast, one genome is represented by a comparatively short fragment). Individual colonies arising from fused protoplasts did not contain different parental genomes without recombinants, but recombinants often occurred without parentals. Several recombinant genotypes often occurred in the same colony, showing a segregation of some, only, of the parental alleles. Complementary genotypes, parental or recombinant, did not occur in the same colony. It is postulated that complete genomes of fused protoplasts usually become fragmented and that crossing-over, often repeated, occurs between the fragments, to generate haploid recombinants. Analysis of fusions between protoplasts of four different genotypes indicated that the average number of protoplasts fusing together was low, but nevertheless appreciable numbers of fusions involved three or four genomes. Crossing-over between them produced recombinants inheriting markers from three or four parents. The generation of nearly random populations of recombinants between two or more parent strains by protoplast fusion under the conditions described appears to have simple applications in industrial and academic strain construction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00268856
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Excision of chromosomal DNA sequences from Streptomyces coelicolor forms a novel family of plasmids detectable in Streptomyces lividans (1981)
    Springer
    Molecular genetics and genomics 184 (1981), S. 230-240 
    Details
    ISSN: 1617-4623
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary When strains of Streptomyces coelicolor A3(2) lacking the previously identified autonomous plasmids SCP1 and SCP2 are crossed with Streptomyces lividans 66, some of the S. lividans progeny are able to elicit zones of growth inhibition (lethal zygosis), previously associated with the transfer of conjugative Streptomyces plasmids, when grown in contact with S. lividans 66. Some such progeny yield covalently closed circular (CCC) plasmid DNA, the size and restriction endonuclease cleavage pattern of which is constant for a particular isolate, but varies among isolates. These plasmid, which have been named SLP1.1, SLP1.2, ect., all confer resistance to lethal zygosis elicited by the others. Genetic and molecular characterization of the plasmids reveals that they are derived from the strA region of the chromosome of S. coelicolor. It is proposed that, before or during mating with S. lividans, the SLP1 sequences are excised from the chromosome, bringing varying regions of the surrounding chromosome with them, and can circularise to yield the SLP1 family of plasmids. Autonomous SLP1 plasmids can also be generated by cleaving total DNA of S. coelicolor with certain restriction enzymes, ligating it, and transforming the DNA into S. lividans. The autonomous SLP1 plasmids exist within S. lividans in a few copies per chromosome, and act as fertility factors. They provide suitable vectors for DNA cloning since the segments of chromosomal DNA carried by the larger members of the family are dispensable.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00272910
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    pIJ101, a multi-copy broad host-range Streptomyces plasmid: Functional analysis and development of DNA cloning vectors (1982)
    Springer
    Molecular genetics and genomics 185 (1982), S. 223-238 
    Details
    ISSN: 1617-4623
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Streptomyces lividans ISP 5434 contains four small high copy number plasmids: pIJ101 (8.9 kb), pIJ102 (4.0 kb), pIJ103 (3.9 kb) and pIJ104 (4.9 kb). The three smaller species appear to be naturally occurring deletion variants of pIJ101. pIJ101 and its in vivo and in vitro derivatives were studied after transformation into S. lividans 66. pIJ101 was found to be self-transmissible by conjugation, to elicit “lethal zygosis” and to promote chromosomal recombination at high frequency in both S. lividans 66 and S. coelicolor A3(2). A restriction endonuclease cleavage map of pIJ101 was constructed for 11 endonucleases; sites for five others were lacking. Many variants of pIJ101 were constructed in vitro by inserting DNA fragments determining resistance to neomycin, thiostrepton or viomycin, and having BamHI termini, into MboI or BclI sites on the plasmid, sometimes with deletion of segments of plasmid DNA. The physical maps of these plasmids were related to their phenotypes in respect of lethal zygosis and transfer properties. In vivo recombination tests between pairs of variant plasmids were also done. These physical and genetic studies indicated that determinants of conjugal transfer occupy less than 2.1 kb of the plasmid. A second segment is required for spread of the plasmid within a plasmid-free culture to produce the normal lethal zygosis phenotype: insertion of foreign DNA in this region caused a marked reduction in the diameter of lethal zygosis zones. The minimum replicon was deduced to be 2.1 kb or less in size; adjacent to this region is a 0.5 kb segment which may be required for stable inheritance of the plasmid. The copy number of several derivatives of pIJ101 in S. lividans 66 was between 40 and 300 per chromosome and appeared to vary with the age or physiological state of the culture. pIJ101 derivatives have a wide host range within the genus Streptomyces: 13 out of 18 strains, of diverse species, were successfully transformed. Knowledge of dispensable DNA segments and the availability of restriction sites for the insertion of DNA, deduced from the properties of plasmids carrying the E. coli plasmid pACYC184 introduced at various sites, was used in the construction of several derivatives of pIJ101 suitable as DNA cloning vectors. These were mostly designed to be non-conjugative and to carry pairs of resistance genes for selection. They include a bifunctional shuttle vector for E. coli and Streptomyces; a Streptomyces viomycin resistance gene of this plasmid is expressed in both hosts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00330791
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Cloning of a Streptomyces gene for an O-methyltransferase involved in antibiotic biosynthesis (1983)
    Springer
    Molecular genetics and genomics 190 (1983), S. 394-398 
    Details
    ISSN: 1617-4623
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The red pigmented antibiotic of Streptomyces coelicolor A3(2) is chemically very similar to the Serratia marcescens pigment, prodigiosin. We have demonstrated by co-synthesis experiments between non-producing mutants of both species that their biosynthetic pathways are similar, and have discovered identities between specific mutants of each organism. Molecular cloning techniques have been employed in order to isolate Streptomyces chromosomal DNA segments which “complement” a mutant defective in the penultimate step of the red biosynthetic pathway: an O-methyltransferase enzyme. In one case, the lesion appears to be repaired by integrative recombination into the chromosome; another case may represent expression from the autonomously replicating recombinant plasmid.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00331065
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    “Strong incompatibility” between derivatives of the Streptomyces multi-copy plasmid pIJ101 (1988)
    Springer
    Molecular genetics and genomics 214 (1988), S. 286-294 
    Details
    ISSN: 1617-4623
    Keywords: Incompatibility ; Single-stranded DNA ; Streptomyces lividans ; Copy number control ; pIJ101
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Some derivatives of pIJ101, a 8.9 kb Streptomyces multi-copy plasmid, can co-exist with each other at similar copy numbers but others are strongly incompatible. The DNA sequence, sti, which causes this “strong incompatibility” was localised on a DNA segment of about 200 bp which is not part of the essential replication region of pIJ101. The sti function is active only when the DNA fragment carrying it is present in the natural orientation with respect to the basic replication region of pIJ101. Pairs of plasmids which either both possess sti in the correct orientation (Sti+) or both lack sti or carry it in reverse orientation (Sti-) can co-exist, but Sti+ and Sti- plasmids cannot; in this case the Sti+ plasmid is retained and the Sti- plasmid is lost. This phenomenon is called strong incompatibility to distinguish it from classical incompatibility where identical or related plamids are incompatible and dissimilar plasmids are compatible. pIJ101 probably replicates via a single-stranded intermediate; sti would be a site where the synthesis of the second (lagging) DNA strand is initiated because Sti- plasmids accumulate more single-stranded plasmid DNA than Sti+ plasmids. The copy number of pIJ101 and its derivatives is influenced by sti and by an additional trans-acting function (cop).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00337723
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Physical and genetical characterisation of a second sex factor, SCP2, for Streptomyces coelicolor A3(2) (1977)
    Springer
    Molecular genetics and genomics 154 (1977), S. 155-166 
    Details
    ISSN: 1617-4623
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Covalently closed circular (ccc) DNA of uniform monomer size (c. 18×106 daltons) and restriction endonuclease cleavage pattern was isolated from strains of S. coelicolor A3(2) of differing constitution in respect of the SCP1 sex factor: SCP1+, SCP1′, SCP1- and NF (integrated SCP1). No such ccc DNA was found in strains of S. lividans 66 or S. parvulus ATCC 12434 whether or not they contained SCP1. These results confirmed that the 18×106 dalton plasmid is not, and does not include, SCP1, which has not so far been isolated by any of a variety of methods. Genetic data served to identify a second sex factor, SCP2, postulated to be present in SCP2+ state in the starting strains and to be capable of mutation to a variant form, SCP2*, with enhanced sex factor activity. From SCP2* strains, SCP2- cultures were isolated, at an average spontaneous frequency of about 0.8%. Crosses of pairs of SCP1- SCP2- strains were almost, but not completely, sterile; thus SCP1 and SCP2 probably contribute nearly all the fertility naturally occurring in the A3(2) strain. The two sex factors share the property of exerting an effect that may be comparable with “lethal zygosis” caused by F in E. coli: it is shown by SCP1-carrying strains against SCP1-, or SCP2* (but not SCP2+) strains against SCP2- and is revealed as a narrow zone of growth inhibition surrounding the plasmid-carrying culture on a background of the appropriate plasmid-negative strain. Genetically defined SCP2- strains lacked the ccc DNA found in SCP2+ and SCP2* strains. Thus this DNA apparently represents the SCP2 sex factor. A preliminary restriction endonuclease cleavage map of SCP2 was constructed, with single sites for EcoRI and HindIII, four sites for SalPI (=PstI) and more than 20 sites for SalGI (SalI).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00330831
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Organisation and functions of the actV A region of the actinorhodin biosynthetic gene cluster of Streptomyces coelicolor (1991)
    Springer
    Molecular genetics and genomics 230 (1991), S. 401-412 
    Details
    ISSN: 1617-4623
    Keywords: Antibiotic biosynthesis ; Antibiotic resistance ; Hydroxylases ; Streptomyces
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Sequence analysis of the actVA region of the actinorhodin biosynthetic gene cluster of Streptomyces coelicolor revealed a succession of six open reading frames (ORFs), all running in the same direction and extending over 5.32 kb. The protein product of actVA-ORF1 strongly resembles that of another gene, elsewhere in the act cluster (actII-ORF2), which codes for a trans-membrane protein previously implicated in actinorhodin export from the mycelium. This suggests that the two gene products may co-operate in actinorhodin export, perhaps being sufficient for self-protection of the organism against suicide. At least four of the other five ORFs are implicated in the control of the C-6 and C-8 ring-hydroxylation reactions, lacking in actVA mutants, that occur at middle to late stages in the actinorhodin biosynthetic pathway. This conclusion was reached by genetic mapping of actVA mutants to actVA-ORF3 and-ORF5 (and perhaps -ORF4), and by the finding of strong resemblances between the protein products of actVA-ORF2 and -ORF6 and the products of genes of the oxytetracycline or tetracenomycin gene clusters that have been implicated in ring-hydroxylation reactions in the biosynthesis of these other aromatic polyketide antibiotics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00280297
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    A mutation of Streptomyces lividans which prevents intraplasmid recombination has no effect on chromosomal recombination (1989)
    Springer
    Molecular genetics and genomics 220 (1989), S. 60-64 
    Details
    ISSN: 1617-4623
    Keywords: Plasmid ; Protoplast fusion ; Rec− mutations ; Recombination ; Streptomyces
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A mutation (rec-46) of Streptomyces lividans, previously shown to prevent (or greatly diminish) homologous and illegitimate intraplasmid recombination, was shown to have no effect on generalised chromosomal recombination occurring in matings or in protoplast fusions, nor to affect homologous recombination between a recombinant plasmid and the host chromosome. By comparison with Escherichia coli mutants defective in various aspects of recombination, the rec-46 mutation is similar to those in recF, recJ, recO and topA.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00260856
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...