keyword
MENU ▼
Read by QxMD icon Read
search

Plasmid curing

keyword
https://www.readbyqxmd.com/read/28649005/crispr-cas9-coupled-recombineering-for-metabolic-engineering-of-corynebacterium-glutamicum
#1
Jae Sung Cho, Kyeong Rok Choi, Cindy Pricilia Surya Prabowo, Jae Ho Shin, Dongsoo Yang, Jaedong Jang, Sang Yup Lee
Genome engineering of Corynebacterium glutamicum, an important industrial microorganism for amino acids production, currently relies on random mutagenesis and inefficient double crossover events. Here we report a rapid genome engineering strategy to scarlessly knock out one or more genes in C. glutamicum in sequential and iterative manner. Recombinase RecT is used to incorporate synthetic single-stranded oligodeoxyribonucleotides into the genome and CRISPR/Cas9 to counter-select negative mutants. We completed the system by engineering the respective plasmids harboring CRISPR/Cas9 and RecT for efficient curing such that multiple gene targets can be done iteratively and final strains will be free of plasmids...
June 22, 2017: Metabolic Engineering
https://www.readbyqxmd.com/read/28646112/crispr-cas12a-assisted-recombineering-in-bacteria
#2
Mei-Yi Yan, Hai-Qin Yan, Gai-Xian Ren, Ju-Ping Zhao, Xiao-Peng Guo, Yi-Cheng Sun
Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a (Cpf1) has emerged as an effective genome editing tool in many organisms. Here, we developed and optimized a CRISPR-Cas12a assisted recombineering system to facilitate genetic manipulation in bacteria. Using this system, point mutations, deletions, insertions, and gene replacements can be easily generated on the chromosome or native plasmids in Escherichia coli, Yersinia pestis, and Mycobacterium smegmatis Because CRISPR-Cas12a-assisted recombineering does not require introduction of an antibiotic resistance gene into the chromosome to select for recombinants, it is an efficient approach for generating markerless and scarless mutations in bacteria...
June 23, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28540425/contribution-of-plasmid-encoded-peptidase-s8-prtp-to-adhesion-and-transit-in-the-gut-of-lactococcus-lactis-ibb477-strain
#3
Joanna Maria Radziwill-Bienkowska, Véronique Robert, Karolina Drabot, Florian Chain, Claire Cherbuy, Philippe Langella, Muriel Thomas, Jacek Karol Bardowski, Muriel Mercier-Bonin, Magdalena Kowalczyk
The ability of Lactococcus lactis to adhere to the intestinal mucosa can potentially prolong the contact with the host, and therefore favour its persistence in the gut. In the present study, the contribution of plasmid-encoded factors to the adhesive and transit properties of the L. lactis subsp. cremoris IBB477 strain was investigated. Plasmid-cured derivatives as well as deletion mutants were obtained and analysed. Adhesion tests were performed using non-coated polystyrene plates, plates coated with mucin or fibronectin and mucus-secreting HT29-MTX intestinal epithelial cells...
May 24, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28526263/n-stearoyl-l-tyrosine-inhibits-the-cell-senescence-and-apoptosis-induced-by-h2o2-in-hek293-tau-cells-via-the-cb2-receptor
#4
Yue Hu, Kai-Yi Zhou, Ze-Jian Wang, Yang Lu, Ming Yin
Although considerable energy and money have been spent trying to inhibit Aβ production and its related metabolic enzyme activities, there are still no drug treatments available to cure even slow for Alzheimer's disease. Therefore, tau protein has been focused recently as the new target for the treatment of Alzheimer's disease. The transfected human embryonic kidney 293 (HEK 293) cells with or without Tau 411 plasmid were used to evaluate the effect of tau protein on cell viability. H2O2 was added to simulate microenvironment of oxidative stress (OS) during aging...
June 25, 2017: Chemico-biological Interactions
https://www.readbyqxmd.com/read/28481933/the-limits-to-growth-energetic-burden-of-the-endogenous-antibiotic-tropodithietic-acid-in-phaeobacter-inhibens-dsm-17395
#5
Sabine Eva Will, Meina Neumann-Schaal, Raymond Leopold Heydorn, Pascal Bartling, Jörn Petersen, Dietmar Schomburg
Phaeobacter inhibens DSM 17395, a model organism for marine Roseobacter group, was studied for its response to its own antimicrobial compound tropodithietic acid (TDA). TDA biosynthesis is encoded on the largest extrachromosomal element of P. inhibens, the 262 kb plasmid, whose curation leads to an increased growth and biomass yield. In this study, the plasmid-cured strain was compared to the wild-type strain and to transposon mutants lacking single genes of the TDA biosynthesis. The data show that the growth inhibition of the wild-type strain can be mainly attributed to the TDA produced by P...
2017: PloS One
https://www.readbyqxmd.com/read/28474344/differential-expression-of-duplicated-binary-toxin-genes-bina-binb-in-lysinibacillus-sphaericus-c3-41
#6
P Fu, X Xiang, Y Ge, Z Yuan, X Hu
Due to the self-produced binary toxins BinA/BinB, some Lysinibacillus sphaericus isolates exhibit high toxicity against mosquito larvae and are utilized in mosquito control programmes. Previous whole-genome sequencing revealed the presence of a large plasmid pBsph in L. sphaericus C3-41, which contains a 30·5-kb duplication of the genome including the binary toxin genes binA/binB. This was confirmed by Southern blot and qPCR experiments in this study. Mutants of L. sphaericus C3-41, bearing disruptions of the chromosomal-bin (C3-41ΔCab ) or the plasmid-bin (C3-41ΔPab ) and a plasmid-cured strain G725, were generated...
May 5, 2017: Letters in Applied Microbiology
https://www.readbyqxmd.com/read/28433723/elimination-of-the-cryptic-plasmid-in-leuconostoc-citreum-by-crispr-cas9-system
#7
Ye-Ji Jang, Seung-Oh Seo, Seul-Ah Kim, Ling Li, Tae-Jip Kim, Sun Chang Kim, Yong-Su Jin, Nam Soo Han
Leuconostoc spp. are important lactic acid bacteria for the fermentation of foods. In particular, L. citreum strains isolated from various foods have been used as host strains for genetic and metabolic engineering studies. In order to develop a food-grade genetic engineering system, L. citreum CB2567 was isolated from Kimchi. However, the isolated bacterium contained a cryptic plasmid which was difficult to eliminate. As the existence of the plasmid might hinder strain engineering, we eliminated the plasmid using an RNA-guided DNA endonuclease CRISPR/Cas9 system...
April 19, 2017: Journal of Biotechnology
https://www.readbyqxmd.com/read/28432094/the-use-of-synthetic-hybrid-strains-to-determine-the-role-of-replicon-3-in-virulence-of-the-burkholderia-cepacia-complex
#8
Kirsty Agnoli, Roman Freitag, Margarida C Gomes, Christian Jenul, Angela Suppiger, Olga Mannweiler, Carmen Frauenknecht, Daniel Janser, Annette C Vergunst, Leo Eberl
The Burkholderia cepacia complex (Bcc) displays a wealth of metabolic diversity with great biotechnological potential, but the utilisation of these bacteria is limited by their opportunistic pathogenicity to humans. The third replicon of the Bcc, megaplasmid pC3 (0.5 to 1.4 Mb, previously chromosome 3), is important for various phenotypes, including virulence, antifungal and proteolytic activities, and the utilization of certain substrates. Approximately half of plasmid pC3 is well-conserved throughout sequenced Bcc members, while the other half is not...
April 21, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28330200/use-of-ca-alginate-immobilized-pseudomonas-aeruginosa-for-repeated-batch-and-continuous-degradation-of-endosulfan
#9
Vijayalakshmi Pradeep, Usha Malavalli Subbaiah
The current investigation is taken up with the aim of studying repeated batch and continuous degradation of Endosulfan, using Ca-alginate immobilized cells of Pseudomonas aeruginosa isolated from an agricultural soil. The work involves the study of genes and enzymes involved in the degradation of the pesticide and was carried out with an objective of reducing the toxicity of Endosulfan by degrading it to less toxic metabolites. The long-term stability of Endosulfan degradation was studied during its repeated batch degradation, carried out over a period of 35 days...
December 2016: 3 Biotech
https://www.readbyqxmd.com/read/28330180/biodegradation-of-propiconazole-by-newly-isolated-burkholderia-sp-strain-bbk_9
#10
Praveen Satapute, Basappa Kaliwal
The isolation of propiconazole (PCZ) degrading bacterium BBK_9 strain was done from paddy soil, and it was identified as Burkholderia sp. based on the morphological characteristics and biochemical properties combined with 16S rRNA gene sequencing analysis. It has been seen that the factors such as temperature and pH influence the biodegradation process. The role of plasmid was studied in the degradation process by plasmid curing method. The PCZ acts as the sole carbon source and as energy substrate which can be utilized by the strain for its growth in Mineral salt medium and degraded 8...
June 2016: 3 Biotech
https://www.readbyqxmd.com/read/28279738/modifying-plasmid-loaded-hsa-nanoparticles-with-cell-penetrating-peptides-cellular-uptake-and-enhanced-gene-delivery
#11
J Mesken, A Iltzsche, D Mulac, K Langer
Gene therapy bears great potential for the cure of a multitude of human diseases. Research efforts focussed on the use of viral delivery vectors in the past decades, neglecting non-viral gene therapies of physical or chemical origin due to low transfection efficiency. However, side effects such as activation of oncogenes and inflammatory reactions upon immune cell activation are major obstacles impeding the clinical applicability of viral gene therapy vectors. The aim of this study was the development of a non-viral gene delivery system based on plasmid-loaded human serum albumin nanoparticles, which are biocompatible, biodegradable, and non-toxic in relevant concentrations...
March 6, 2017: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/28277944/the-galleria-mellonella-larvae-as-an-in-vivo-model-for-evaluation-of-shigella-virulence
#12
Shoshana Barnoy, Hanan Gancz, Yuewei Zhu, Cary L Honnold, Daniel V Zurawski, Malabi M Venkatesan
Shigella spp. causing bacterial diarrhea and dysentery are human enteroinvasive bacterial pathogens that are orally transmitted through contaminated food and water and cause bacillary dysentery. Although natural Shigella infections are restricted to humans and primates, several smaller animal models are used to analyze individual steps in pathogenesis. No animal model fully duplicates the human response and sustaining the models requires expensive animals, costly maintenance of animal facilities, veterinary services and approved animal protocols...
February 13, 2017: Gut Microbes
https://www.readbyqxmd.com/read/28261566/efflux-pump-overexpression-contributes-to-tigecycline-heteroresistance-in-salmonella-enterica-serovar-typhimurium
#13
Yi Chen, Daxing Hu, Qijing Zhang, Xiao-Ping Liao, Ya-Hong Liu, Jian Sun
Bacterial heteroresistance has been identified in several combinations of bacteria and antibiotics, and it complicated the therapeutic strategies. Tigecycline is being used as one of the optimal options for the treatment of infections caused by multidrug-resistant Salmonella. This study investigated whether heterorresistance to tigecycline exists in a Salmonella enterica serovar Typhimurium strain harboring the oqxAB-bearing IncHI2 plasmid pHXY0908. MIC and population analyses were performed to evaluate population-wide susceptibility to tigecycline...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/28245276/plasmid-interference-for-curing-antibiotic-resistance-plasmids-in-vivo
#14
Muhammad Kamruzzaman, Shereen Shoma, Christopher M Thomas, Sally R Partridge, Jonathan R Iredell
Antibiotic resistance increases the likelihood of death from infection by common pathogens such as Escherichia coli and Klebsiella pneumoniae in developed and developing countries alike. Most important modern antibiotic resistance genes spread between such species on self-transmissible (conjugative) plasmids. These plasmids are traditionally grouped on the basis of replicon incompatibility (Inc), which prevents coexistence of related plasmids in the same cell. These plasmids also use post-segregational killing ('addiction') systems, which poison any bacterial cells that lose the addictive plasmid, to guarantee their own survival...
2017: PloS One
https://www.readbyqxmd.com/read/28238083/elimination-of-indigenous-linear-plasmids-in-streptomyces-hygroscopicus-var-jinggangensis-and-streptomyces-sp-fr008-to-increase-validamycin-a-and-candicidin-productivities
#15
Chenyang Lu, Hang Wu, Xiurong Su, Linquan Bai
Giant linear plasmids, which replicate independently of the chromosomes, widely exist in actinobacteria. Previous studies mostly focused on the replication and evolution of the linear plasmids or the secondary metabolite gene clusters and the resistance gene clusters therein. However, the relationships of the linear plasmids to the productivities of secondary metabolites have not been studied. In this work, we developed a method to eliminate the indigenous linear plasmid pSHJG1 in Streptomyces hygroscopicus var...
February 25, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28192223/emergence-of-multi-drug-resistance-among-soil-bacteria-exposing-to-insecticides
#16
Kirubakaran Rangasamy, Murugan Athiappan, Natarajan Devarajan, Javid A Parray
Impacts of pesticide exposure on the soil microbial flora and cross resistance to antibiotics have not been well documented. Development of antibiotic resistance is a common issue among soil bacteria which are exposing to pesticides continuously at sub-lethal concentration. The present study was focused to evaluate the correlation between pesticide exposures and evolution of multi drug resistance among isolates collected from soil applied with insecticides. Twenty five insecticide (Monochrotophos) degrading bacteria were isolated from contaminated agricultural soil...
April 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28179404/a-plasmodium-vivax-plasmid-dna-and-adenovirus-vectored-malaria-vaccine-encoding-blood-stage-antigens-ama1-and-msp142-in-a-prime-boost-heterologous-immunization-regimen-partially-protects-aotus-monkeys-against-blood-stage-challenge
#17
Nicanor Obaldia, Michael G Stockelman, William Otero, Jennifer A Cockrill, Harini Ganeshan, Esteban N Abot, Jianfeng Zhang, Keith Limbach, Yupin Charoenvit, Denise L Doolan, De-Chu C Tang, Thomas L Richie
Malaria is caused by parasites of the genus Plasmodium, which are transmitted to humans by the bites of Anopheles mosquitoes. After the elimination of Plasmodium falciparum, it is predicted that Plasmodium vivax will remain an important cause of morbidity and mortality outside Africa, stressing the importance of developing a vaccine against P. vivax malaria. In this study, we assessed the immunogenicity and protective efficacy of two P. vivax antigens, apical membrane antigen 1 (AMA1) and the 42-kDa C-terminal fragment of merozoite surface protein 1 (MSP142) in a plasmid recombinant DNA prime/adenoviral (Ad) vector boost regimen in Aotus monkeys...
April 2017: Clinical and Vaccine Immunology: CVI
https://www.readbyqxmd.com/read/28161562/hindrance-of-1-4-dioxane-biodegradation-in-microcosms-biostimulated-with-inducing-or-non-inducing-auxiliary-substrates
#18
Mengyan Li, Yuanyuan Liu, Ya He, Jacques Mathieu, James Hatton, William DiGuiseppi, Pedro J J Alvarez
A microcosm study was conducted to assess two biostimulation strategies (relative to natural attenuation) to bioremediate 1,4-dioxane contamination at a site in west Texas. Dioxane concentrations were relatively low (<300 μg/L), which represents a potential challenge to sustain and induce specific degraders. Thus, biostimulation was attempted with an auxiliary substrate known to induce dioxane-degrading monooxygenases (i.e., tetrahydrohyran [THF]) or with a non-inducing growth substrate (1-butanol [1-BuOH])...
April 1, 2017: Water Research
https://www.readbyqxmd.com/read/28154555/key-impact-of-an-uncommon-plasmid-on-bacillus-amyloliquefaciens-subsp-plantarum-s499-developmental-traits-and-lipopeptide-production
#19
Giulia Molinatto, Laurent Franzil, Sébastien Steels, Gerardo Puopolo, Ilaria Pertot, Marc Ongena
The rhizobacterium Bacillus amyloliquefaciens subsp. plantarum S499 (S499) is particularly efficient in terms of the production of cyclic lipopeptides, which are responsible for the high level of plant disease protection provided by this strain. Sequencing of the S499 genome has highlighted genetic differences and similarities with the closely related rhizobacterium B. amyloliquefaciens subsp. plantarum FZB42 (FZB42). More specifically, a rare 8008 bp plasmid (pS499) harboring a rap-phr cassette constitutes a major distinctive element between S499 and FZB42...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28108611/reversal-of-diabetes-in-nod-mice-by-clinical-grade-proinsulin-and-il-10-secreting-lactococcus-lactis-in-combination-with-low-dose-anti-cd3-depends-on-the-induction-of-foxp3-positive-t-cells
#20
Tatiana Takiishi, Dana Paulina Cook, Hannelie Korf, Guido Sebastiani, Francesca Mancarella, João Paulo Monteiro Carvalho Mori Cunha, Clive Wasserfall, Noelia Casares, Juan José Lasarte, Lothar Steidler, Pieter Rottiers, Francesco Dotta, Conny Gysemans, Chantal Mathieu
The introduction of β-cell autoantigens via the gut through Lactococcus lactis (L. lactis) has been demonstrated to be a promising approach for diabetes reversal in NOD mice. Here we show that a combination therapy of low-dose anti-CD3 with a clinical-grade self-containing L. lactis, appropriate for human application, secreting human proinsulin and interleukin-10, cured 66% of mice with new-onset diabetes, which is comparable to therapy results with plasmid-driven L. lactis Initial blood glucose concentrations (<350 mg/dL) and insulin autoantibody positivity were predictors of the stable reversal of hyperglycemia, and decline in insulin autoantibody positivity was an immune biomarker of therapeutic outcome...
February 2017: Diabetes
keyword
keyword
45791
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"