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ABSTRACT Protein production strategies in bacteria are often limited due to the need for cell lysis and complicated purification schemes. To avoid these challenges, researchers have developed bacterial strains capable of secreting heterologous protein products outside the cell, but secretion titers often remain too low for commercial applicability. Improved understanding of the link between secretion system structure and its secretory abilities can help overcome the barrier to engineering higher secretion titers. Here, we investigated this link with the PrgI protein, the monomer of the secretory channel of the type 3 secretion system (T3SS) of Salmonella enterica. Despite detailed knowledge of the PrgI needle’s assembly and structure, little is known about how its structure influences its secretory capabilities. To study this, we recently constructed a comprehensive codon mutagenesis library of the PrgI protein utilizing a novel one-pot recombineering approach. We then screened this library for functional T3SS assembly and secretion titer by measuring the secretion of alkaline phosphatase using a high-throughput activity assay. This allowed us to construct a first-of-its-kind secretion fitness landscape to characterize the PrgI needle’s mutability at each position as well as the mutations which lead to enhanced T3SS secretion. We discovered new design rules for building a functional T3SS as well as identified hypersecreting mutants. This work can be used to increase understanding of the T3SS’s assembly and identify further targets for engineering. This work also provides a blueprint for future efforts to engineer other complex protein assemblies through the construction of fitness landscapes.IMPORTANCEProtein secretion offers a simplified alternative method for protein purification from bacterial hosts. However, the current state-of-the-art methods for protein secretion in bacteria are still hindered by low yields relative to traditional protein purification strategies. Engineers are now seeking strategies to enhance protein secretion titers from bacterial hosts, often through genetic manipulations. In this study, we demonstrate that protein engineering strategies focused on altering the secretion apparatus can be a fruitful avenue toward this goal. Specifically, this study focuses on how changes to the PrgI needle protein from the type 3 secretion system from Salmonella enterica can impact secretion titer. We demonstrate that this complex is amenable to comprehensive mutagenesis studies and that this can yield both PrgI variants with increased secretory capabilities and insight into the normal functioning of the type 3 secretion system.

Este artículo presenta el estudio de un caso en el que se articulan fuentes orales y fuentes documentales, se evidencia que más allá de las posturas dicotómicas entre los defensores de cada tipo de fuentes, su integración puede permitir la descripción densa o a profundidad de detalles que pueden sustentar la explicación de los procesos históricos. Este es un estudio sobre religión y política, la temática que se aborda es sobre el proceso de involucramiento de cristianos al movimiento social y político de la década de 1970 y 1980. Se trata de un caso concreto: la Coordinadora Nacional de la Iglesia Popular (1980-1985), constituida por un grupo de sacerdotes, religiosas, laicos y seminaristas vinculados a la insurgencia salvadoreña, que se desarticuló y dividió en 1983, en medio de las circunstancias de lucha ideológica al interior de las FPL.

Improving piezoelectric strain and voltage constant generally compromises piezoelectric performance and mechanical softness. Here, the authors report a bond weakening strategy for organic-inorganic hybrid piezoelectrics and mitigated these issues.

Luego del asesinato de Monseñor Óscar Romero (1980), un grupo de sacerdotes, religiosas, seminaristas y laicos decidieron formar la Coordinadora Nacional de la Iglesia Popular (CONIP), espacio desde el cual buscaron sostener —en aras del proceso revolucionario salvadoreño— el trabajo pastoral masivo que pretendió la Coordinadora. Aunque no todos los miembros de la CONIP fueron militantes de las organizaciones político-militares, compartieron el habitus militante que se configuró entre los grupos e individuos identificados con la Nueva Izquierda durante las décadas de 1970 y 1980. Realidad: Revista de Ciencias Sociales y Humanidades No. 161, 2023: 9-24.

Abstract Background Host-parasite interactions represent complex co-evolving systems in which genetic and associated phenotypic variation within a species can significantly affect selective pressures on traits, such as host immunity, in the other. While often modelled as a two-species interaction between host and parasite, some systems are more complex due to effects of host enemies, intraguild predation, and endosymbionts, all of which affect host immunity. However, it remains unclear how these factors, combined with genetic variation in the host and the parasitoid, affect host immunity. We address this question in an important agricultural pest system, the pea aphid Acyrthosiphon pisum, which shows significant intraspecific variability in immunity to the parasitoid wasp Aphidius ervi. In a complex experiment, we use a quantitative genetic design in the parasitoid, two ecologically different aphid lineages and the aphid lion Chrysoperla carnea as an intraguild predator to unravel the complex interdependencies. Results We demonstrate that aphid immunity as a key trait of this complex host-parasite system is affected by intraspecific genetic variation in the parasitoid and the aphid, the interaction of intraspecific genetic variation with intraguild predation, and differences in defensive endosymbionts between aphid lineages. Further, aphid lineages differ in their altruistic behaviour whereby infested aphids move away from the clonal colony to facilitate predation. Conclusions Our findings provide new insights into the influence of endosymbiosis and genetic variability in an important host-parasitoid system which is influenced by natural enemies of the parasitoid and the aphid, including its endosymbiont communities. We show that endosymbiosis can mediate or influence the evolutionary arms race between aphids and their natural enemies. The outcome of these complex interactions between species has significant implications for understanding the evolution of multitrophic systems, including eco-agricultural settings.

E-learning is one of the revolutions in the education system that encourages the acceleration of quality learning. The Covid-19 pandemic has become a catalyst for accelerating the implementation of e-learning in Jayapura, Papua. Teachers are required to be able to adapt to this rapid change. Thus, E-learning becomes essential amid the pandemic, yet the ICT indicators reveal many barriers to implementing it. This study aims to assess the level of readiness of the teachers in implementing the e-learning system. Data was collected by distributing questionnaires to the teachers from elementary to high school in Jayapura City. Technology infrastructures, human resources, and e-learning content were the main variables to measure. This study indicated that based on teachers' perceptions, more than 70 percent were using google classroom as an e-learning platform. The level of readiness was level 3 (ready with minor improvements). Infrastructures, internet access, and e-learning content availability are the indicators that needed extra attention for improvement

Technology plays an important role in life. Information and Communication Technology (ICT) has expanded educational options by enabling teachers and students to use technology to reorganize existing education and training systems. An adequate number of studies have identified the various benefits of implementing e-learning. However, not all institutions that implement online learning get the expected results. In addition, teachers in schools are not homogeneous. This study analyzes e-learning readiness in rural areas during the Covid-19 pandemic. This type of research is descriptive and quantitative. The subjects of this study were ten teachers, three IT staff, two foundation administrators, and 87 students from elementary and junior high schools. Data was collected using questionnaires and interviews. Data were analyzed using Aydin and Tasci's E-Learning Readiness Score, which describes learning outcomes. The results of this study indicate that overall, e-learning is ready to be implemented due to the leadership's commitment in the form of funds and policy support for the implementation of e-learning. Factors that need serious attention are technology infrastructure, human resources, and content.

The microstrip antennas matured and improved over the last 25 years. Throughout these years, the limitations, and specifications of the said antennas have been overcome and significantly improved. Known to be lowprofile, suitable for mobile, and lightweight, these microstrip antennas are the focus of this research. In this paper, the researchers designed a microstrip antenna with varying lengths and substrates. They tested the changes and the effects in microstrip antennas of different lengths, along with altering substrates. To verify the differences, the researchers compared the performance parameters maximum gain (dBi), minimum gain (dBi), and S11 graph on each tested length and changed substrate. The rough set theory was used to determine the optimal design via MATLAB. From there, the researchers analyzed the results gathered and drew their respective conclusions. Additionally, they saw and compared each data result to know what antenna has the best performance parameters. From the results, a change in the dimension will result in a decrease in the said performance parameters. Furthermore, the change in substrate thickness also diminishes these changes. [ABSTRACT FROM AUTHOR]