Exconjugants
Mostrando 1-12 de 51 artigos, teses e dissertações.
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1. Produção de mutantes de Streptomyces clavuligerus nos genes lat, cvm7P e rpoZ e estudo de seus efeitos sobre a produção de ácido clavulânico / Production of Streptomyces clavuligerus mutants in the genes lat, cvm7P and rpoZ, and study their effects on acid production clavulanic
Molecular biology and genetic engineering have been deployed widely in recent years, several protocols have been established, presenting new methodologies capable of altering the genetics of bacterial strains industrial interest. This research had as main objectives: (1) the construction of the following plasmids: plat, pAMB4 and pAMB3RpoZneo, (2) th
Publicado em: 2010
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2. Transfer Among Erwinia spp. and Other Enterobacteria of Antibiotic Resistance Carried on R Factors
Antibiotic resistance carried on R factors was transferred by conjugation from Escherichia coli B/r and Shigella flexneri 1a to Erwinia spp. Tetracycline resistance (TetR) carried on R factor R100 drd-56 was transferred from E. coli B/r to strains of Erwinia amylovora, E. aroideae, E. atroseptica, E. chrysanthemi, E. cytolytica, E. dissolvens, E. herbicola,
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3. Genetic Transfer of Episomic Elements Among Erwinia Species and Other Enterobacteria: F′lac+
The episomic element F′lac+ was transferred, probably by conjugation, from Escherichia coli to Lac− strains of Erwinia herbicola, Erwinia amylovora, and Erwinia chrysanthemi (but not to several other Erwinia spp. In preliminary trials). The lac genes in the exconjugants of the Erwinia spp. showed varying degrees of stability depending on the strain (stab
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4. Plasmid- and chromosome-mediated dissimilation of naphthalene and salicylate in Pseudomonas putida PMD-1.
Pseudomonas putida PMD-1 dissimilates naphthalene (Nah), salicylate (Sal), and benzoate (Ben) via catechol which is metabolized through the meta (or alpha-keto acid) pathway. The ability to utilize salicylate but not naphthalene was transferred from P. putida PMD-1 to several Pseudomonas species. Agarose gel electrophoresis of deoxyribonucleic acid (DNA) fro
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5. Rp4 Promotion of Transfer of a Large Agrobacterium Plasmid Which Confers Virulence
Introduction of RP4 plasmid into Agrobacterium tumefaciens promotes the transfer on solid medium of large virulence-associated plasmids from virulent donor strains to a plasmidless avirulent recipient. Exconjugants were selected for the ability to utilize octopine or nopaline as the sole source of arginine, traits which are coded for by virulence-associated
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6. Transmission of lac by the Sex Factor E in Erwinia Strains from Human Clinical Sources
Lactose-utilizing (Lac+) strains of Erwinia spp. from human clinical material transfer lac by conjugation to plant strains of Erwinia herbicola and Erwinia amylovora, to other Erwinia strains from human clinical sources, and also to Escherichia coli, Paracolobactrum arizonae, Salmonella typhimurium, and Shigella dysenteriae. The frequency of this transfer va
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7. Insertional specificity of transposon Tn5 in Acinetobacter sp.
Suicide plasmid pJB4JI, containing transposon Tn5 and phage Mu, was introduced from Escherichia coli 1830 into Acinetobacter sp. strain HO1-N and Acinetobacter calcoaceticus BD413. Kanamycin-resistant (Kmr) exconjugants of HO1-N and BD413, isolated on complex medium, were screened for auxotrophic requirements. Over 10,000 Kmr clones were examined, but no aux
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8. Fusion and Compatibility of Camphor and Octane Plasmids in Pseudomonas
The octane (OCT) plasmid in Pseudomonas putida derived from the ω-hydroxylase-carrying strain of Coon and coworkers is transferable to the camphor (CAM) plasmid-bearing strain by conjugation or by transduction. While the majority of the Cam +Oct+ exconjugants segregate Cam+ or Oct+ cells, exconjugants with stable Cam +Oct+ phenotype (CAM-OCT) can be detecte
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9. Genetic transfer by conjugation in the thermophilic green sulfur bacterium Chlorobium tepidum.
The broad-host-range IncQ group plasmids pDSK519 and pGSS33 were transferred by conjugation from Escherichia coli into the thermophilic green sulfur bacterium Chlorobium tepidum. C. tepidum exconjugants expressed the kanamycin and ampicillin-chloramphenicol resistances encoded by pDSK519 and pGSS33, respectively. Ampicillin resistance was a particularly good
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10. Role of Pili in Bacterial Conjugation1
We describe techniques for isolating individual pairs of mating Escherichia coli and observing them under the light microscope. Some pairs achieved close cell-to-cell contact, whereas others remained loosely connected by invisible connections which may be F pili. After 30 min of mating, the pairs were separated and allowed to grow into clones. That many exco
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11. Characterization of transmissible genetic elements from sucrose-fermenting Salmonella strains.
Two of seven sucrose-fermenting Salmonella strains obtained from clinical sources were found capable of conjugal transfer of the sucrose fermentation (Scr+) property to the Escherichia coli K-12 strain WR3026. The genetic elements conferring this Scr+ property, designated scr-53 and scr-94, were then conjugally transmissible from Escherichia coli WR3026 Scr+
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12. Formation of SXT Tandem Arrays and SXT-R391 Hybrids
SXT is an integrative and conjugative element (ICE) isolated from Vibrio cholerae. This ∼100-kb ICE encodes resistance to multiple antibiotics and integrates site specifically into the chromosome. SXT excises from the chromosome to form a circular but nonreplicative extrachromosomal molecule that is required for its transfer. Here we found that a significa
American Society for Microbiology.