Recombinant production of the lantibiotic nisin using Corynebacterium glutamicum in a two-step process

Background The bacteriocin nisin is naturally produced by Lactococcus lactis as an inactive prepeptide that is modified posttranslationally resulting in five (methyl-)lanthionine rings characteristic for class Ia bacteriocins. Export and proteolytic cleavage of the leader peptide results in release of active nisin. By targeting the universal peptidoglycan precursor lipid II, nisin has a broad target spectrum including important human pathogens such as Listeria monocytogenes and methicillin-resistant Staphylococcus aureus strains. Industrial nisin production is currently performed using natural producer strains resulting in rather low product purity and limiting its application to preservation of dairy food products. Results We established heterologous nisin production using the biotechnological workhorse organism Corynebacterium glutamicum in a two-step process. We demonstrate successful biosynthesis and export of fully modified prenisin and its activation to mature nisin by a purified, soluble variant of the nisin protease NisP (sNisP) produced in Escherichia coli. Active nisin was detected by a L. lactis sensor strain with strictly nisin-dependent expression of the fluorescent protein mCherry. Following activation by sNisP, supernatants of the recombinant C. glutamicum producer strain cultivated in standard batch fermentations contained at least 1.25 mg/l active nisin. Conclusions We demonstrate successful implementation of a two-step process for recombinant production of active nisin with C. glutamicum. This extends the spectrum of bioactive compounds that may be produced using C. glutamicum to a bacteriocin harboring complex posttranslational modifications. Our results provide a basis for further studies to optimize product yields, transfer production to sustainable substrates and purification of pharmaceutical grade nisin.

Creep of CarbFix basalt: influence of rock–fluid interaction

Geological carbon sequestration provides permanent CO2 storage to mitigate the current high concentration of CO2 in the atmosphere. CO2 mineralization in basalts has been proven to be one of the most secure storage options. For successful implementation and future improvements of this technology, the time-dependent deformation behavior of reservoir rocks in the presence of reactive fluids needs to be studied in detail. We conducted load-stepping creep experiments on basalts from the CarbFix site (Iceland) under several pore fluid conditions (dry, H2O saturated and H2O + CO2 saturated) at temperature, T≈80 ∘C and effective pressure, Peff=50 MPa, during which we collected mechanical, acoustic and pore fluid chemistry data. We observed transient creep at stresses as low as 11 % of the failure strength. Acoustic emissions (AEs) correlated strongly with strain accumulation, indicating that the creep deformation was a brittle process in agreement with microstructural observations. The rate and magnitude of AEs were higher in fluid-saturated experiments than in dry conditions. We infer that the predominant mechanism governing creep deformation is time- and stress-dependent subcritical dilatant cracking. Our results suggest that the presence of aqueous fluids exerts first-order control on creep deformation of basaltic rocks, while the composition of the fluids plays only a secondary role under the studied conditions.

The economics of Forest Carbon Sequestration: A Bibliometric Analysis

Carbon sequestration in forests has increasingly captured the attention of scientists as a strategy for climate change mitigation and environmental sustainability. In this era of huge carbon emission, being a low-carbon and cost-effective technology, the economic analysis of forest carbon sequestration holds higher importance for the successful implementation and intended outcomes. This study elucidates a scientometric view of the research structure and thematic evolution of economic studies on forest carbon sequestration based on 1,439 articles over the time slice 2001-2021. The bibliographic data has been retrieved from the Dimensions database which accommodates a large coverage of research publications and also provides easy access to essential scholarly data and information. Vosviewer and Biblioshiny software tools have opted for visualization and evaluation purposes of bibliometric data. This study employs various measures of bibliometric analysis like co-authorship, bibliographic coupling, citation and keyword analysis to find out the principal articles, authors, journals, most frequent keywords and highest publishing countries and institutions in this field and the results show that the number of publications has escalated substantially in the last five years, Popp A, 2017 (305 citations) and André P C Faaij (11 documents) are the most cited article and the most productive author, respectively, Bradford’s law calculates 21 core journals out of total 503 journals among which Forest Policy and Economics is on the top, and the most productive country and institution are the USA and University of Florida, respectively. The study also investigates key publishing subject categories and the number of publications covered under each Sustainable Development Goals. The overall outcome of this bibliometric study confers an in-depth understanding of the various dimensions of economic analysis on forest carbon sequestration, its development pattern in the last 20 years and also provides emerging themes for future references.

Sunflower Seed Cake and Larvae MassRheological Properties Analysis During Pressing WithVarying Temperature, Pressure and Oil Content

For the successful implementation of alternative protein sourcesforbiorefinery, optimization of the process parameters is crucial. Knowledge of the rheological propertiesis necessary for the design and development of appropriate equipment and process calculations.The objective of this research was to evaluate the effect of the following pre-treatments: temperature, pressure andeffect of initial oil content on the rheological properties of sunflower seedcake and larvae tissue. The rheological behavior of two protein sourceswas determined by using a rotational viscometer with a hydraulic system and thermostatic bath attached to the equipment. Using the mathematical apparatus and experimental data it was observed that the plastic viscosity of the sunflower seed cake corresponded to the viscosity of the vegetable oil, which confirmed the Bingham rheology assumption put forward in this work. For the larvae mass, a Hershey Buckley fluid model was proposed.A positive linear relationship was found for pressure and a negativelinear relationship was found for the oil content of the sunflower seed cake and larvae tissue on shear stress. Keywords: rheological property, sunflower seed cake, larvae, pulsed electricaldischarge, viscoplasticity flow, Bingham model, modelling

The economics of Forest Carbon Sequestration: A Bibliometric Analysis

Carbon sequestration in forests has increasingly captured the attention of scientists as a strategy for climate change mitigation and environmental sustainability. In this era of huge carbon emission, being a low-carbon and cost-effective technology, the economic analysis of forest carbon sequestration holds higher importance for the successful implementation and intended outcomes. This study elucidates a scientometric view of the research structure and thematic evolution of economic studies on forest carbon sequestration based on 1,439 articles over the time slice 2001-2021. The bibliographic data has been retrieved from the Dimensions database which accommodates a large coverage of research publications and also provides easy access to essential scholarly data and information. Vosviewer and Biblioshiny software tools have opted for visualization and evaluation purposes of bibliometric data. This study employs various measures of bibliometric analysis like co-authorship, bibliographic coupling, citation and keyword analysis to find out the principal articles, authors, journals, most frequent keywords and highest publishing countries and institutions in this field and the results show that the number of publications has escalated substantially in the last five years, Popp A, 2017 (305 citations) and André P C Faaij (11 documents) are the most cited article and the most productive author, respectively, Bradford’s law calculates 21 core journals out of total 503 journals among which Forest Policy and Economics is on the top, and the most productive country and institution are the USA and University of Florida, respectively. The study also investigates key publishing subject categories and the number of publications covered under each Sustainable Development Goals. The overall outcome of this bibliometric study confers an in-depth understanding of the various dimensions of economic analysis on forest carbon sequestration, its development pattern in the last 20 years and also provides emerging themes for future references.

A Cross-National Study of the Effects of Education on Pre-Service Teachers’ Attitudes, Intentions, Concerns, and Self-Efficacy Regarding Inclusive Education

This study reports on a cross-national comparison of inclusion-oriented teacher-education programs. Canada and Germany have implemented inclusion in teacher education with the aim of improving inclusion in schools. Previous studies have shown the importance of latent characteristics of prospective teachers for the successful implementation of inclusion in schools and have pointed to the role of inclusion-oriented teacher education in developing these teacher characteristics. To measure potential changes in attitudes, intentions, concerns, and self‑efficacy, 132 student teachers from Germany and Canada were surveyed before and after a course about inclusive education. Internationally validated scales were used: Attitudes towards Inclusion Scale (AIS), Intention to Teach in Inclusive Classroom Scale (ITICS), Concerns about Inclusive Education Scale (CIES), and the Teacher Efficacy for Inclusive Practices scale (TEIP). The results of the German and Canadian groups differed: while significant changes in self-efficacy occurred between the first and second measurement points in both countries, the outcome for other factors varied. Significant changes in intentions to use inclusive teaching practices were found in Canada but not in Germany. The results are discussed in the context of the role of teacher-education programs in fostering inclusive teaching practices.

Antimonopoly Compliance: Review of Foreign Practice. Part I

The article contains the best foreign practices of implementing the of antimonopoly compliance Institute (compliance) in order to identify and manage the risks of violations of competition law and the possibility of preventing these violations by companies. The article presents the definition of compliance, describes the experience of foreign competition authorities in development, organization and implementation of compliance programs. Special attention is paid to the potential benefits that business receives as part of the successful implementation of the antimonopoly compliance system, including the possibility of mitigating circumstance in case a company commits an antimonopoly offense.

Controlling the Stress State of the Coating during Plasma Spraying

Coatings obtained by spraying materials with a high-temperature gas jet onto a substrate followed by thermal treatment of the deposited materials (thermal gas coatings) are increasingly being used. The practical experience of using thermal spray coatings, accumulated over the past 20–30 years in industries, shows that in this way it is possible, as a rule, to reduce the wear of machine parts operating under various conditions by a factor of 2–5. The effectiveness of the technology has also been proven in the protection of products from corrosion and thermal damage. The efficiency of the applied materials is determined by their structure, which largely depends on the choice of the composition of the material, the method, and modes of application. A comprehensive solution to these issues with the study of the mechanism of the processes of formation of thermal gas coatings will create a scientific basis for the technology for its successful implementation in production. At the same time, the importance of studying the processes and optimizing the technological parameters of spraying and subsequent coating treatment increases. Optimization is carried out, as a rule, according to the results of experiments. Let us consider the study on the example of the development of wear-resistant composite coatings with solid lubricant inclusions with the substantiation of the technique and criteria for optimizing technological parameters taking into account the most important properties of sprayed protective coatings.