1,720,984 research outputs found
Complete genome sequences of pLMA1 and pLMA7, two large linear plasmids of Micrococcus strains isolated from a high-altitude lake in Argentina
Full text linkThe two linear plasmids pLMA1 (109,112 bp) and pLMA7 (82,075 bp) from Micrococcus strains were isolated from a high-altitude lake in the Argentinean Puna, sequenced, and annotated. These extrachromosomal elements are probably conjugative and harbor genes potentially involved in coping with the harsh conditions in such extreme environments.Fil: Dib, Julian Rafael. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Perez, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Schuldes, Jörg. Universität Göttingen; Alemania. Charité ? Universitätsmedizin Berlin;Fil: Poehlein, Anja. Universität Göttingen; AlemaniaFil: Wagenknecht, Martin. Boehringer Ingelheim Gmbh Austria; Austria. Westfalische Wilhelms Universitat; AlemaniaFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Meinhardt, Friedhelm. Westfalische Wilhelms Universitat; AlemaniaFil: Daniel, Rolf. Universität Göttingen; Alemani
The two putative comS homologs of the biotechnologically important Bacillus licheniformis do not contribute to competence development
No full textIn Bacillus subtilis, natural genetic competence is subject to complex genetic regulation and quorum sensing dependent. Upon extracellular accumulation of the peptide-pheromone ComX, the membrane-bound sensor histidine kinase ComP initiates diverse signaling pathways by activating-among others-DegQ and ComS. While DegQ favors the expression of extracellular enzymes rather than competence development, ComS is crucial for competence development as it prevents proteolytic degradation of ComK, the key transcriptional activator of all genes required for the uptake and integration of DNA. In Bacillus licheniformis, ComX/ComP sensed cell density negatively influences competence development, suggesting differences from the quorum-sensing-dependent control mechanism in Bacillus subtilis. Here, we show that each of six investigated strains possesses both of two different, recently identified putative comS genes. When expressed from an inducible promoter, none of the comS candidate genes displayed an impact on competence development neither in B. subtilis nor in B. licheniformis. Moreover, disruption of the genes did not reduce transformation efficiency. While the putative comS homologs do not contribute to competence development, we provide evidence that the degQ gene as for B. subtilis negatively influences genetic competency in B. licheniformis
Genetic evidence for a novel competence inhibitor in the industrially important Bacillus licheniformis
No full textAbstract Natural genetic competence renders bacteria able to take up and, in case there is sufficient homology to the recipient’s chromosome, integrate exogenously supplied DNA. Well studied in Bacillus subtilis, genetic competence is—in several aspects—known to be differently regulated in Bacillus licheniformis. We now report on the identification of a novel, chromosomally encoded homolog of a competence inhibitor in B. licheniformis (ComI) that has hitherto only been described as a plasmid borne trait in the ancestral B. subtilis NCIB3610. Bioinformatical analysis that included 80 Bacillus strains covering 20 different species revealed a ComI encoding gene in all of the examined B. licheniformis representatives, and was identified in few among the other species investigated. The predicted ComI of B. licheniformis is a highly conserved peptide consisting of 28 amino acids. Since deletion of comI in B. licheniformis DSM13 resulted in twofold increased transformation efficiency by genetic competence and overexpression resulted in threefold decreased transformability, the function as a competence inhibitor became evident
First Complete Sequence of a Giant Linear Plasmid from a Micrococcus Strain Isolated from an Extremely High-Altitude Lake
Full text linkMicrococcus sp. V7, an actinobacterial strain adapted to the extreme conditions of the Laguna Vilama, an extremely high-altitude (4,600mabove sea level) lake in the Argentinian Puna, was found to carry the giant linear plasmid pLMV7. We determined its sequence (92,815 bp) as a prerequisite to the investigation of its role for survival in such a harsh environment.Fil: Dib, Julian Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Schuldes, Jörg. Georg August Universität Göttingen; AndorraFil: Thürner, Andrea. Georg August Universität Göttingen; AndorraFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Daniel, Rolf. Georg August Universität Göttingen; AndorraFil: Meinhardt, Friedhelm. No especifíca
Strategies and approaches in plasmidome studies, uncovering plasmid diversity disregarding of linear elements?
Full text linkThe term plasmid was originally coined for circular, extrachromosomal genetic elements. Today, plasmids are widely recognised not only as important factors facilitating genome restructuring but also as vehicles for the dissemination of beneficial characters within bacterial communities. Plasmid diversity has been uncovered by means of culture dependent or independent approaches, such as endogenous or exogenous plasmid isolation as well as PCR-based detection or transposon-aided capture, respectively. High-throughput-sequencing made possible to cover total plasmid populations in a given environment, i.e. the plasmidome, and allowed to address the quality and significance of self-replicating genetic elements. Since such efforts were and still are rather restricted to circular molecules, here we put equal emphasis on the linear plasmids which despite their frequent occurrence in a large number of bacteria are largely neglected in prevalent plasmidome conceptions.Fil: Dib, Julian Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; ArgentinaFil: Wagenknecht, Martin. Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Münster.; AlemaniaFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; ArgentinaFil: Meinhardt, Friedhelm. Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Münster.; Alemani
Structural peculiarities of linear megaplasmid, pLMA1, from Micrococcus luteus interfere with pyrosequencing reads assembly
Full text linkDifferent strains of Micrococcus luteus, isolated from high-altitude Argentinean wetlands, were recently reported to harbour the linear plasmids pLMA1, pLMH5 and pLMV7, all of which with 5′-covalently attached terminal proteins. The link between pLMA1 and the host’s erythromycin resistance as well as further presumptive qualities prompted us to perform a detailed characterization. When the 454 technology was applied for direct sequencing of gel-purified pLMA1, assembly of the reads was impossible. However, combined Sanger/454 sequencing of cloned pLMA1 fragments, covering altogether 23 kb of the 110-kb spanning plasmid, allowed numerous sequence repeats of varying in lengths to be identified thus rendering an explanation for the above 454 assembly failure. A large number of putative transposase genes were identified as well. Furthermore, a region with five putative iteron sequences is possibly involved in pLMA1 replication.Fil: Wagenknecht, Martin. Westfalische Wilhelms Universitat; AlemaniaFil: Dib, Julian Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Thürmer, Andrea. Universität Göttingen; AlemaniaFil: Rolf, Daniel. Universität Göttingen; AlemaniaFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Meinhardt, Friedhelm. Westfalische Wilhelms Universitat; Alemani
Complete Genome Sequence of pAP13, a Large Linear Plasmid of a Brevibacterium Strain Isolated from a Saline Lake at 4,200 Meters above Sea Level in Argentina
Full text linkpAP13 is an 89 kb-linear plasmid hosted by Brevibacterium sp. Ap13, an actinobacterium isolated from the feces of a flamingo from an extremely high-altitude lake in Argentina. Because of the ecological importance of the genus Brevibacterium, the absolute lack of information concerning Brevibacterium linear plasmids, as well as the as the possible ecological significance of this unusual plasmid, pAP13 was completely sequenced, including the inversely oriented termini.Fil: Dib, Julian Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Schuldes, Jörg. Georg August Universität; AlemaniaFil: Thürner, Andrea. Georg August Universität; AlemaniaFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Daniel, Rolf. Georg August Universität; AlemaniaFil: Meinhardt, Friedhelm. No especifíca
First report of linear megaplasmids in the genus Micrococcus
Full text linkHigh-altitude wetlands (above 4200 m) in the northwest of Argentina are considered pristine and extreme environments. Micrococcus sp. A1, H5, and V7, isolated from such environments, were shown to contain linear megaplasmids, designated pLMA1, pLMH5, and pLMV7, respectively. As known from linear plasmids of other actinomycetes, all three plasmids were resistant to λ exonuclease treatment, which is consistent with having terminal proteins covalently attached to their 5′ DNA ends. Electrophoretic mobility, Southern analysis, and restriction endonuclease patterns revealed pLMA1 and pLMH5 being indistinguishable plasmids, even though they were found in different strains isolated from two distant wetlands – Laguna Azul and Laguna Huaca Huasi. Analysis of 16S rDNA sequences of Micrococcus sp. A1, H5, and V7 suggested a close relationship to Micrococcus luteus. Typing of isolates was performed using fingerprint patterns generated by BOX-PCR. Plasmid-deficient strains, generated from Micrococcus sp. A1, showed a significantly decreased resistance level for erythromycin.Fil: Dib, Julian Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Wagenknecht, Martin. Westfalische Wilhelms Universitat; AlemaniaFil: Hill, Russel T.. University Of Maryland. Biotechnology Institute. Center Of Marine Biotechnology; Estados UnidosFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Meinhardt, Friedhelm. Westfalische Wilhelms Universitat; Alemani
Facilitation of Direct Conditional Knockout of Essential Genes in <i>Bacillus licheniformis</i> DSM13 by Comparative Genetic Analysis and Manipulation of Genetic Competence
No full textABSTRACT
The genetic manageability of the biotechnologically important
Bacillus licheniformis
is hampered due to its poor transformability, whereas
Bacillus subtilis
efficiently takes up DNA during genetic competence, a quorum-sensing-dependent process. Since the sensor histidine kinase ComP, encoded by a gene of the quorum-sensing module
comQXPA
of
B. licheniformis
DSM13, was found to be inactive due to an insertion element within
comP
, the coding region was exchanged with a functional copy. Quorum sensing was restored, but the already-poor genetic competence dropped further. The inducible expression of the key regulator for the transcription of competence genes, ComK, in
trans
resulted in highly competent strains and facilitated the direct disruption of genes, as well as the conditional knockout of an essential operon. As ComK is inhibited at low cell densities by a proteolytic complex in which MecA binds ComK and such inhibition is antagonized by the interaction of MecA with ComS (the expression of the latter is controlled by cell density in
B. subtilis
), we performed an
in silico
analysis of MecA and the hitherto unidentified ComS, which revealed differences for competent and noncompetent strains, indicating that the reduced competence possibly is due to a nonfunctional coupling of the
comQXPA
-encoded quorum module and ComK. The obtained increased genetic tractability of this industrial workhorse should improve a wide array of scientific investigations.
</jats:p
Novel linear megaplasmid from Brevibacterium sp. isolated from extreme environment
Full text linkBrevibacterium sp. Ap13, isolated from flamingo's feces in Laguna Aparejos, a high-altitude lake located at approximately 4,200 m in the northwest of Argentina was previously found to be resistant to multiple antibiotics, and was therefore screened for plasmids that may be implicated in antibiotic resistance. Brevibacterium sp. Ap13 was found to contain two plasmids of approximately 87 and 436 kb, designated pAP13 and pAP13c, respectively. Only pAP13 was stably maintained and was extensively characterized by pulsed-field gel electrophoresis to reveal that this plasmid is linear and likely has covalently linked terminal proteins associated with its 5' ends. This is the first report of a linear plasmid in the genus Brevibacterium and may provide a new tool for genetic manipulation of this commercially important genus.Fil: Dib, Julian Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Wagenknecht, Martin. Westfalische Wilhelms Universitat; AlemaniaFil: Hill, Russell T.. University of Maryland; Estados UnidosFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Meinhardt, Friedhelm. Westfalische Wilhelms Universitat; Alemani
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