Enhancing oxidative stress resistance in Bifidobacterium thermophilum using a novel overexpression vector and transformation protocol
Publication date: Available online 14 July 2017 Source:Plasmid Author(s): Marc J.A. Stevens, Adriano Venturini, Christophe Lacroix, Leo Meile Bifidobacterium thermophilum is encountered in the GI-tract of pigs and infants. Here we provide a transformation protocol for B. thermophilum and a novel expression vector for this species. The protocol resulted in transformation rates of 1×103 transformed cells per μg DNA. Transformation was shown to be dependent on the presence of fructo-oligosaccharides during growth, polyethylene glycol in the electroporation buffer, and on methylation of the vector. The Escherichia coli...
Source: Plasmid - July 15, 2017 Category: Biotechnology Source Type: research
Characterization of pHeBE7, an IncFII-type virulence-resistance plasmid carrying blaCTX-M-98b, blaTEM-1, and rmtB genes, detected in Escherichia coli from a chicken isolate in China
In this study, we sequenced the complete pHeBE7 plasmid, an 86,015-bp plasmid that contains the bla CTX-M-98b, bla TEM-1, rmtB, and traT genes, using whole-genome sequencing. The backbone of pHeBE7 shows a high similarity (>99%) to pMC-NDM, which carries the bla NDM-1 gene, however its mosaic regions remain relatively unique among sequenced plasmids. We discovered that a typical ISEcp1-bla CTX-M-IS903 element in the mosaic region harbors the bla CTX-M-98b gene. Conjugation and growth competition assays indicate that pHeBE7 can be easily transmitted and that it confers a limited fitness cost to the recipient cell. Th...
Source: Plasmid - July 6, 2017 Category: Biotechnology Source Type: research
Evolutionary persistence of tripartite integrative and conjugative elements
In this study, examination of ICE3s revealed that most symbiosis genes are carried on the large α fragment. Some ICE3-β and γ regions also carry genes that potentially contribute to the symbiosis, or to persistence in the soil environment, but these regions have been frequently subjected to recombination events including deletions, insertions and recombination with genes located on other integrative elements. Examination of a new ICE3 in M. ciceri Ca181 revealed it has jettisoned the genetic cargo from its β region and recruited a serine recombinase gene within its γ region, resulting in replacement of one of the thre...
Source: Plasmid - June 30, 2017 Category: Biotechnology Source Type: research
pIP40a, a type 1 IncC plasmid from 1969 carries the integrative element GIsul2 and a novel class II mercury resistance transposon
Publication date: Available online 31 May 2017 Source:Plasmid Author(s): Christopher J. Harmer, Mohammad Hamidian, Ruth M. Hall The 167.5kb sequence of the conjugative IncC plasmid pIP40a, isolated from a Pseudomonas aeruginosa in 1969, was analysed. pIP40a confers resistance to kanamycin, neomycin, ampicillin, sulphonamides and mercuric ions, and several insertions in a type 1 IncC backbone were found, including copies of IS3, Tn1000 and a novel mercury resistance transposon, Tn6182. The antibiotic resistance genes were in two locations. Tn6023, containing the aphA1 kanamycin and neomycin resistance gene, is in a par...
Source: Plasmid - May 31, 2017 Category: Biotechnology Source Type: research
Acquisition of a second multi-drug resistance-encoding element by IncM1 plasmid pACM130 abolished conjugative transfer
Publication date: Available online 30 May 2017 Source:Plasmid Author(s): Karen E. Preston, John A. Tine Within the IncM plasmid family there is a lineage that has a transposon Tn1721-based multiple-resistance island inserted in the backbone gene mucB. So far, this group includes R1215, p202c, pIGT15, pARM26, and pACM1, from Europe and the USA. A new member of this group, pACM130, was isolated at the same American hospital as pACM1 and has a similar resistance island, but also carries a copy of Tn1331 that interrupts the traY gene in the conjugation operon. The conjugative phenotype of this plasmid has been abolished, t...
Source: Plasmid - May 30, 2017 Category: Biotechnology Source Type: research
Brownian ratchet mechanisms of ParA-mediated partitioning
Publication date: Available online 18 May 2017 Source:Plasmid Author(s): Longhua Hu, Anthony G. Vecchiarelli, Kiyoshi Mizuuchi, Keir C. Neuman, Jian Liu (Source: Plasmid)
Source: Plasmid - May 19, 2017 Category: Biotechnology Source Type: research
A dual-site gateway cloning system for simultaneous cloning of two genes for plant transformation
Publication date: Available online 9 May 2017 Source:Plasmid Author(s): Aboulela Mostafa, Yuji Tanaka, Kohji Nishimura, Shoji Mano, Tetsuya Kimura, Tsuyoshi Nakagawa Analyses of the subcellular localization of proteins and protein-protein interaction networks are essential to uncover the molecular basis of diverse biological processes in plants. To this end, we have created a Gateway cloning-compatible vector system, named dual-site (DS) Gateway cloning system to allow simple cloning of two expression cassettes in a binary vector and to express them simultaneously in plant cells. In the DS Gateway cloning system, (...
Source: Plasmid - May 10, 2017 Category: Biotechnology Source Type: research
Conjugative plasmids enable the maintenance of low cost non-transmissible plasmids
Publication date: Available online 28 April 2017 Source:Plasmid Author(s): Martin Werisch, Uta Berger, Thomas U. Berendonk Some plasmids can be transferred by conjugation to other bacterial hosts. But almost half of the plasmids are non-transmissible. These plasmid types can only be transmitted to the daughter cells of their host after bacterial fission. Previous studies suggest that non-transmissible plasmids become extinct in the absence of selection of their encoded traits, as plasmid-free bacteria are more competitive. Here, we aim to identify mechanisms that enable non-transmissible plasmids to persist, even if t...
Source: Plasmid - April 28, 2017 Category: Biotechnology Source Type: research
The evolution of plasmid stability: Are infectious transmission and compensatory evolution competing evolutionary trajectories?
Publication date: Available online 28 April 2017 Source:Plasmid Author(s): James P.J. Hall, Michael A. Brockhurst, Calvin Dytham, Ellie Harrison Conjugative plasmids are widespread and play an important role in bacterial evolution by accelerating adaptation through horizontal gene transfer. However, explaining the long-term stability of plasmids remains challenging because segregational loss and the costs of plasmid carriage should drive the loss of plasmids though purifying selection. Theoretical and experimental studies suggest two key evolutionary routes to plasmid stability: First, the evolution of high conjugati...
Source: Plasmid - April 28, 2017 Category: Biotechnology Source Type: research
Regulation of conjugative transfer of plasmids and integrative conjugative elements
Publication date: Available online 22 April 2017 Source:Plasmid Author(s): Luis Alfredo Bañuelos-Vazquez, Gonzalo Torres Tejerizo, Susana Brom Horizontal gene transfer has been recognized as one of the principal contributors to bacterial evolution and diversification. One of the mechanisms involved in this process is conjugative transfer of plasmids and Integrative Conjugative Elements (ICEs). Plasmids and ICEs often encode traits beneficial for bacterial survival in specific environments, or for the establishment of symbiosis or pathogenesis, in addition to genes allowing conjugative transfer. In this review, we ana...
Source: Plasmid - April 22, 2017 Category: Biotechnology Source Type: research
Horizontal transfer of chromosomal markers mediated by the large conjugative plasmid pXO16 from Bacillus thuringiensis serovar israelensis
Publication date: Available online 20 April 2017 Source:Plasmid Author(s): Lionel Makart, Florian Commans, Annika Gillis, Jacques Mahillon pXO16, a large plasmid originating from Bacillus thuringiensis serovar israelensis, displays unique conjugation capacities: besides efficient self-transfer, it is able to mobilize and retro-mobilize non-conjugative plasmids, including those missing an oriT and/or a mob gene, also known as “non-mobilizable” plasmids. In this paper, another peculiar transfer property of pXO16 is described. This element is indeed able to transfer chromosomal loci at frequencies of ca. 10−5–10...
Source: Plasmid - April 21, 2017 Category: Biotechnology Source Type: research
Evidence that compatibility of closely related replicons in Clostridium perfringens depends on linkage to parMRC-like partitioning systems of different subfamilies
In conclusion, we have provided the first direct evidence of plasmid incompatibility in Clostridium spp. and have shown experimentally that the compatibility of conjugative C. perfringens plasmids correlates with the presence of parMRC-like partitioning systems of different phylogenetic subfamilies. (Source: Plasmid)
Source: Plasmid - April 11, 2017 Category: Biotechnology Source Type: research
Annotation of plasmid genes
Publication date: Available online 30 March 2017 Source:Plasmid Author(s): Christopher M. Thomas, Nicholas R. Thomson, Ana M. Cerdeño-Tárraga, Celeste J. Brown, Eva M. Top, Laura S. Frost Good annotation of plasmid genomes is essential to maximise the value of the rapidly increasing volume of plasmid sequences. This short review highlights some of the current issues and suggests some ways forward. Where a well-studied related plasmid system exists we recommend that new annotation adheres to the convention already established for that system, so long as it is based on sound principles and solid experimental eviden...
Source: Plasmid - March 31, 2017 Category: Biotechnology Source Type: research
Sequence of the R1 plasmid and comparison to F and R100
We present the complete genome sequence of R1 along with a brief review of the current knowledge concerning its various genetic systems and a comparison to the F and R100 plasmids. R1 is 97,566 nucleotides long and contains 120 genes. The plasmid consists of a backbone largely similar to that of F and R100, a Tn21-like transposon that is nearly identical to that of R100, and a unique 9-kb sequence that bears some resemblance to sequences found in certain Klebsiella oxytoca strains. These three regions of R1 are separated by copies of the insertion sequence IS1. Overall, the structure of R1 and comparison to F and R100 sugg...
Source: Plasmid - March 28, 2017 Category: Biotechnology Source Type: research
Protein depletion using the arabinose promoter in Xanthomonas citri subsp. citri
Publication date: Available online 24 March 2017 Source:Plasmid Author(s): Lilian A. Lacerda, Lucia B. Cavalca, Paula M.M. Martins, José S. Govone, Maurício Bacci, Henrique Ferreira Xanthomonas citri subsp. citri (X. citri) is a plant pathogen and the etiological agent of citrus canker, a severe disease that affects all the commercially important citrus varieties, and has worldwide distribution. Citrus canker cannot be healed, and the best method known to control the spread of X. citri in the orchards is the eradication of symptomatic and asymptomatic plants in the field. However, in the state of São Paulo, Braz...
Source: Plasmid - March 25, 2017 Category: Biotechnology Source Type: research
