Construction of pDUO: A bicistronic shuttle vector series for dual expression of recombinant proteins
Publication date: Available online 16 December 2016 Source:Plasmid Author(s): Paul A. Nakata Our ability to genetically manipulate microbial systems is often hampered by the availability of genetic tools. Thus, there is a need for the continued expansion of our molecular tool box. In support of this expansion, this study reports the design, construction, and validation of a new bicistronic shuttle vector series, pDUO, for the dual expression of genes in different hosts. Each vector was designed and constructed to contain two araC-p BAD inducible promoter systems for tight control over gene expression. Each araC-p BAD pr...
Source: Plasmid - December 15, 2016 Category: Biotechnology Source Type: research
A novel group of IncQ1 plasmids conferring multidrug resistance
Publication date: Available online 1 December 2016 Source:Plasmid Author(s): M. Oliva, R. Monno, P. D'Addabbo, G. Pesole, A.M. Dionisi, M. Scrascia, M. Chiara, D.S. Horner, C. Manzari, I. Luzzi, C. Calia, A.M. D'Erchia, C. Pazzani The IncQ is a group of non-conjugative but mobilisable plasmids that are stably maintained and found in a wide range of bacteria, contributing to the spread of antimicrobial resistance genes and to the insurgence of multidrug resistant bacteria. Here we report the identification, in clinical Salmonella Typhimurium strains, of an IncQ1 plasmid (pNUC) conferring resistance to sulfame...
Source: Plasmid - December 1, 2016 Category: Biotechnology Source Type: research
Tailor-made fibroblast-specific and antibiotic-free interleukin 12 plasmid for gene electrotransfer-mediated cancer immunotherapy
Publication date: Available online 24 November 2016 Source:Plasmid Author(s): Urska Kamensek, Natasa Tesic, Gregor Sersa, Spela Kos, Maja Cemazar Electrotransfer mediated delivery of interleukin-12 (IL-12) gene, encoded on a plasmid vector, has already been demonstrated to have a potent antitumor efficacy and great potential for clinical application. In the present study, our aim was to construct an optimized IL-12-encoding plasmid that is safe from the regulatory point of view. In light of previous studies demonstrating that IL-12 should be released in a tumor localized manner for optimal efficacy, the strong ubiqu...
Source: Plasmid - November 23, 2016 Category: Biotechnology Source Type: research
Effects of the sequence and orientation of an expression cassette in tobacco transformed by dual Bt genes
This study investigated the effects of the sequence arrangement and orientation of a target gene expression cassette in vectors on expression levels to determine the optimal combination for highly efficient multi-gene expression. Five plant transformation vectors were constructed using dual Bt genes, Cry1Ac and Cry3A, which differed in the sequence arrangement and orientation of the target gene expression cassette. Through an Agrobacterium-mediated method, 5 vectors were used for the genetic transformation of tobacco to obtain transgenic lines. Fluorescence quantitative PCR showed that the target genes were expressed at th...
Source: Plasmid - November 15, 2016 Category: Biotechnology Source Type: research
An efficient system for the generation of marked genetic mutants in members of the genus Burkholderia
Publication date: Available online 5 November 2016 Source:Plasmid Author(s): Sravanthi Shastri, Helena L. Spiewak, Aderonke Sofoluwe, Vigdis A. Eidsvaag, Atif H. Asghar, Tyrone Pereira, Edward H. Bull, Aaron T. Butt, Mark S. Thomas To elucidate the function of a gene in bacteria it is vital that targeted gene inactivation (allelic replacement) can be achieved. Allelic replacement is often carried out by disruption of the gene of interest by insertion of an antibiotic-resistance marker followed by subsequent transfer of the mutant allele to the genome of the host organism in place of the wild-type gene. However, ...
Source: Plasmid - November 4, 2016 Category: Biotechnology Source Type: research
Analysis of pCERC7, a small antibiotic resistance plasmid from a commensal ST131 Escherichia coli, defines a diverse group of plasmids that include various segments adjacent to a multimer resolution site and encode the same NikA relaxase accessory protein enabling mobilisation
Publication date: Available online 5 November 2016 Source:Plasmid Author(s): Robert A. Moran, Ruth M. Hall The ampicillin resistance plasmid pCERC7, carrying transposon Tn2 with an IS4 insertion, was detected in the draft genome of a commensal Escherichia coli isolate. The genome data also revealed that this isolate belongs to ST131, clade B. pCERC7 is 9712bp comprised of a 3319bp backbone, Tn2::IS4 (6388bp) and 5bp of target site duplication, and was present at a copy number of 40. pCERC7 is related to several plasmids composed of only the backbone, or the backbone with the Tn2 insertion in the same position. These pl...
Source: Plasmid - November 4, 2016 Category: Biotechnology Source Type: research
Corrigendum to “Construction of a highly-active, liver-specific transcriptional regulatory element through combination of the albumin promoter and α-fetoprotein enhancer” [Plasmid 65 (2011) 125–31]
Publication date: Available online 26 October 2016 Source:Plasmid Author(s): E.Q. Chen, X.Q. Song, Y.L. Wang, T.Y. Zhou, L. Bai, L. Liu, C. Liu, X. Cheng, H. Tang (Source: Plasmid)
Source: Plasmid - October 26, 2016 Category: Biotechnology Source Type: research
Enhanced plasmid loss in bacterial populations exposed to the antimicrobial compound irgasan delivered from interpenetrating polymer network silicone hydrogels
This study, however, illustrates the ability of IPNs to release an impregnated compound into a liquid suspension to induce a significant biological impact on growing bacterial cells. (Source: Plasmid)
Source: Plasmid - October 12, 2016 Category: Biotechnology Source Type: research
The pUltra plasmid series: A robust and flexible tool for fluorescent labeling of Enterobacteria
Publication date: Available online 29 September 2016 Source:Plasmid Author(s): Despoina A.I. Mavridou, Diego Gonzalez, Abigail Clements, Kevin R. Foster Fluorescent labeling has been an invaluable tool for the study of living organisms and bacterial species are no exception to this. Here we present and characterize the pUltra plasmids which express constitutively a fluorescent protein gene (GFP, RFP, YFP or CFP) from a strong synthetic promoter and are suitable for the fluorescent labeling of a broad range of Enterobacteria. The amount of expressed fluorophore from these genetic constructs is such, that the contours ...
Source: Plasmid - September 29, 2016 Category: Biotechnology Source Type: research
Conjugative DNA-transfer in Streptomyces, a mycelial organism
Publication date: Available online 28 September 2016 Source:Plasmid Author(s): L. Thoma, G. Muth Conjugative DNA-transfer in the Gram-positive mycelial soil bacterium Streptomyces, well known for the production of numerous antibiotics, is a unique process involving the transfer of a double-stranded DNA molecule. Apparently it does not depend on a type IV secretion system but resembles the segregation of chromosomes during bacterial cell division. A single plasmid-encoded protein, TraB, directs the transfer from the plasmid-carrying donor to the recipient. TraB is a FtsK-like DNA-translocase, which recognizes a specific...
Source: Plasmid - September 27, 2016 Category: Biotechnology Source Type: research
Destabilization of IncA and IncC plasmids by SGI1 and SGI2 type Salmonella genomic islands
Publication date: Available online 9 September 2016 Source:Plasmid Author(s): Christopher J. Harmer, Mohammad Hamidian, Stephanie J. Ambrose, Ruth M. Hall Both the Salmonella genomic islands (SGI) and the conjugative IncC plasmids are known to contribute substantially to the acquisition of resistance to multiple antibiotics, and plasmids in the A/C group are known to mobilize the Salmonella genomic island SGI1, which also carries multiple antibiotic resistance genes. Plasmid pRMH760 (IncC; A/C2) was shown to mobilize SGI1 variants SGI1-I, SGI1-F, SGI1-K and SGI2 from Salmonella enterica to Escherichia coli where it w...
Source: Plasmid - September 12, 2016 Category: Biotechnology Source Type: research
A super twin T-DNA vector that allows independent gene expression during Agrobacterium-mediated transformation
In this study, we designed and constructed a super twin T-DNA vector (pTRIDT313-g) containing two independent T-DNA cassettes―one for the selection gene Hyg and the other for the target gene Gus―to produce marker-free transgenic lines. The resulting vector was transformed into tobacco, and polymerase chain reaction (PCR) analysis showed four types of gene combinations in the T1 and T2 generations: Gus only, Hyg only, Gus+Hyg, and untransformed lines. The intermediate region from the T-DNA of the right border of Hyg to the left border of Gus in the Hyg and Gus lines was not amplified. Genome walking confirmed that the H...
Source: Plasmid - September 8, 2016 Category: Biotechnology Source Type: research
A large conjugative Acinetobacter baumannii plasmid carrying the sul2 sulphonamide and strAB streptomycin resistance genes
Publication date: Available online 4 September 2016 Source:Plasmid Author(s): Mohammad Hamidian, Stephanie J. Ambrose, Ruth M. Hall Acinetobacter baumannii is an important nosocomial pathogen that often complicates treatment because of its high level of resistance to antibiotics. Though plasmids can potentially introduce various genes into bacterial strains, compared to other Gram-negative bacteria, information about the unique A. baumannii plasmid repertoire is limited. Here, whole genome sequence data was used to determine the plasmid content of strain A297 (RUH875), the reference strain for the globally disseminate...
Source: Plasmid - September 3, 2016 Category: Biotechnology Source Type: research
PCR-based typing of IncC plasmids
Publication date: Available online 30 August 2016 Source:Plasmid Author(s): Christopher J. Harmer, Ruth M. Hall IncC (A/C2) plasmids are known to play an important role in the spread of multiple antibiotic resistance determinants, including extended-spectrum β-lactamases and carbapenamases, amongst Gram negative bacterial populations. The ability to identify and track these plasmids is valuable in epidemiological and clinical studies. A recent comparative analysis of the backbones of sequenced IncC plasmids identified two distinct lineages, type 1 and type 2, with different evolutionary histories. Here, a simple PCR m...
Source: Plasmid - August 29, 2016 Category: Biotechnology Source Type: research
Development and application of a general plasmid reference material for GMO screening
In this study, 11 commonly used genetic elements involving three promoters (P-35S, P-FMV35S and P-NOS), four marker genes (Bar, NPTII, HPT and Pmi), and four terminators (T-NOS, T-35S, T-g7 and T-e9), together with the reference gene fragments from six major crops of maize, soybean, rapeseed, rice, cotton and wheat, were co-integrated into the same single plasmid to construct a general reference plasmid pBI121-Screening. The suitability test of pBI121-Screening plasmid as reference material indicated that the non-target sequence on the pBI121-Screening plasmid did not affect the PCR amplification efficiencies of screening ...
Source: Plasmid - August 4, 2016 Category: Biotechnology Source Type: research
