Editing plant genomes without introducing foreign DNA into cells may alleviate regulatory concerns related to genetically modified plants. We transfected preassembled complexes of purified Cas9 ...protein and guide RNA into plant protoplasts of Arabidopsis thaliana, tobacco, lettuce and rice and achieved targeted mutagenesis in regenerated plants at frequencies of up to 46%. The targeted sites contained germline-transmissible small insertions or deletions that are indistinguishable from naturally occurring genetic variation.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Bacillus licheniformis is a well-known platform strain for production of industrial enzymes. However, the development of genetically stable recombinant B. licheniformis for high-yield enzyme ...production is still laborious. Here, a pair of plasmids, pUB-MazF and pUB'-EX1, were firstly constructed. pUB-MazF is a thermosensitive, self-replicable plasmid. It was able to efficiently cure from the host cell through induced expression of an endoribonuclease MazF, which is lethal to the host cell. pUB'-EX1 is a nonreplicative and integrative plasmid. Its replication was dependent on the thermosensitive replicase produced by pUB-MazF. Transformation of pUB'-EX1 into the B. licheniformis BL-UBM harboring pUB-MazF resulted in both plasmids coexisting in the host cell. At an elevated temperature, and in the presence of isopropyl-1-thio-beta-d-galactopyranoside and kanamycin, curing of the pUB-MazF and multiple-copy integration of pUB'-EX1 occurred, simultaneously. Through this procedure, genetically stable recombinants integrated multiple copies of amyS, from Geobacillus stearothermophilus ATCC 31195 were facilely obtained. The genetic stability of the recombinants was verified by repeated subculturing and shaking flask fermentations. The production of alpha-amylase by recombinant BLiS-002, harboring five copies of amyS, in a 50-l bioreactor reached 50 753 U/ml after 72 hr fermentation. This strategy therefore has potential for production of other enzymes in B. licheniformis and for genetic modification of other Bacillus species. Keywords: Chromosomal integration, MazF, Bacillus licheniformis, Overexpression, alpha-Amylase
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Pesticide impacts are usually discussed in the context of applied amounts while disregarding the large but environmentally relevant variations in substance-specific toxicity. Here, we systemically ...interpret changes in the use of 381 pesticides over 25 years by considering 1591 substance-specific acute toxicity threshold values for eight nontarget species groups. We find that the toxicity of applied insecticides to aquatic invertebrates and pollinators has increased considerably-in sharp contrast to the applied amount-and that this increase has been driven by highly toxic pyrethroids and neonicotinoids, respectively. We also report increasing applied toxicity to aquatic invertebrates and pollinators in genetically modified (GM) corn and to terrestrial plants in herbicide-tolerant soybeans since approximately 2010. Our results challenge the claims of a decrease in the environmental impacts of pesticide use.
The availability of L-arginine in tumours is a key determinant of an efficient anti-tumour T cell response
. Consequently, increases of typically low L-arginine concentrations within the tumour may ...greatly potentiate the anti-tumour responses of immune checkpoint inhibitors, such as programmed death-ligand 1 (PD-L1)-blocking antibodies
. However, currently no means are available to locally increase intratumoural L-arginine levels. Here we used a synthetic biology approach to develop an engineered probiotic Escherichia coli Nissle 1917 strain that colonizes tumours and continuously converts ammonia, a metabolic waste product that accumulates in tumours
, to L-arginine. Colonization of tumours with these bacteria increased intratumoural L-arginine concentrations, increased the number of tumour-infiltrating T cells and had marked synergistic effects with PD-L1 blocking antibodies in the clearance of tumours. The anti-tumour effect of these bacteria was mediated by L-arginine and was dependent on T cells. These results show that engineered microbial therapies enable metabolic modulation of the tumour microenvironment leading to enhanced efficacy of immunotherapies.
The continuous advancement of analytical technology has provided methods with increasing sensitivity and precision to detect genetically modified organisms (GMOs). Novel analytical strategy-based ...detection methods are alternatives to conventional polymerase chain reaction (PCR)-mediated assays, which are still the gold standard in this field. However, PCR primers and probes cannot be reused, which makes the technique uneconomical. Surface plasmon resonance (SPR) is an optical and label-free technique for studying ligand-analyte interactions, especially for DNA hybridization, and several SPR biosensors have been described for the detection of nucleic acids. Here, a multiplexed, regenerable and real-time SPR biosensor for the detection of GMOs is described. A biosensor was constructed for qualitative detection of T-nos, CaMV35S and cry1A and had good specificity and sensitivity. The limit of detection (LOD) of this biosensor was 0.1 nM without any signal amplification. Furthermore, our biosensor could be stably regenerated more than 100 times over at least 20 days and showed good reproducibility. This nucleic acid SPR biosensor has potential for application in other types of biological detection.
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•Construction of a new multiplex biosensor for GMO detection.•Reusability and stability of our biosensor improve its applicability.•Real-time monitoring achieves quantification detection.•MR-SPR shows high sensitivity and selectivity for DNA detection.
In keeping with emerging consumer trends, the food industry is continually searching for cheaper and healthier protein ingredients to replace those derived from animal sources (e.g., whey, casein, ...gelatin, and ovalbumin), gluten-based proteins (e.g., wheat), and soy. Pea protein shows promise in filling this niche because it is non-genetically modified organism (GMO), gluten-free, nutritious, and of low allergenicity. This review discusses structure-function relationships of pea protein isolates, the impact of extraction techniques used to produce the isolate, and the impact of cultivar and environment on ingredient performance in terms of solubility, water- and oil-holding capacities, emulsifying, foaming, and gelation properties.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The pressing global issue of food insecurity due to population growth, diminishing land and variable climate can only be addressed in agriculture by improving both maximum crop yield potential and ...resilience. Genetic modification is one potential solution, but has yet to achieve worldwide acceptance, particularly for crops such as wheat. Trehalose-6-phosphate (T6P), a central sugar signal in plants, regulates sucrose use and allocation, underpinning crop growth and development. Here we show that application of a chemical intervention strategy directly modulates T6P levels in planta. Plant-permeable analogues of T6P were designed and constructed based on a 'signalling-precursor' concept for permeability, ready uptake and sunlight-triggered release of T6P in planta. We show that chemical intervention in a potent sugar signal increases grain yield, whereas application to vegetative tissue improves recovery and resurrection from drought. This technology offers a means to combine increases in yield with crop stress resilience. Given the generality of the T6P pathway in plants and other small-molecule signals in biology, these studies suggest that suitable synthetic exogenous small-molecule signal precursors can be used to directly enhance plant performance and perhaps other organism function.
Introduction: Cancer disease is known due to its unregulated proliferation of cells that have evolved from the body's regular cells. The disease develops as a result of epigenetic and genetic ...modifications, tumor suppressor gene inactivation, and oncogene activation. The present work describes an environmentally benign approach for the synthesis of manganese oxide nanoparticles (MnO.sub.2 NPs) using Gmelina arborea fruit extract (GAE) in an aqueous medium. Methods: The study evaluated the formation of MnO.sub.2 NPs and their anticancer efficacy against MCF-7 breast cancer cell line. Results: The formation of MnO.sub.2 NPs was confirmed through powder X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HR-TEM). The crystalline nature of as-prepared MnO.sub.2 NPs was evident from XRD pattern. The morphology of the material was studied using SEM analysis, which suggested a rod-like nature with an average diameter of 50 nm. Further, the TEM and HR-TEM images confirmed the rod shape of the as-prepared MnO.sub.2 NPs with an interplanar distance of 0.271 nm. In addition, the concentric rings from selected area electron diffraction (SAED) analysis show the crystalline nature of the as-prepared material, which further supports the obtained XRD pattern. The anticancer efficacy of MnO.sub.2 NPs was evaluated against MCF-7 breast cancer cell line, which showed up to 96% inhibition of the cells at 400 microg/mL concentration. Conclusion: Bio-conjugation of MnO.sub.2 NPs can provide enough scope for the therapeutic use of Gmelina arborea, assuming appropriate mechanistic evaluations are conducted. Keywords: Gmelina arborea, MnO.sub.2 NPs, HR-TEM, MCF-7
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