A Micrarchaeon isolate is covered by a proteinaceous S-Layer

In previous publications, it was hypothesized that Micrarchaeota cells are covered by two individual membrane systems. This study proves that at least the recently cultivated “ Candidatus Micrarchaeum harzensis A_DKE” possesses an S-layer covering its cytoplasmic membrane. The potential S-layer protein was found to be among the proteins with the highest abundance in “ Ca. Micrarchaeum harzensis A_DKE” and in silico characterisation of its primary structure indicated homologies to other known S-layer proteins. Homologues of this protein were found in other Micrarchaeota genomes, which raises the question of whether the ability to form an S-layer is a common trait within this phylum. The S-layer protein seems to be glycosylated and the Micrarchaeon expresses genes for N-glycosylation under cultivation conditions, despite not being able to synthesize carbohydrates. Electron micrographs of freeze-etched samples of a previously described co-culture, containing Micrarchaeum A_DKE and a Thermoplasmatales member as its host organism, verified the hypothesis of an S-layer on the surface of “ Ca. Micrarchaeum harzensis A_DKE”. Both organisms are clearly distinguishable by cell size, shape and surface structure. Importance Our knowledge about the DPANN superphylum, which comprises several archaeal phyla with limited metabolic capacities, is mostly based on genomic data derived from cultivation-independent approaches. This study examined the surface structure of a recently cultivated member “ Candidatus Micrarchaeum harzensis A_DKE”, an archaeal symbiont dependent on an interaction with a host organism for growth. The interaction requires direct cell contact between interaction partners, a mechanism which is also described for other DPANN archaea. Investigating the surface structure of “ Ca. Micrarchaeum harzensis A_DKE” is an important step towards understanding the interaction between Micrarchaeota and their host organisms and living with limited metabolic capabilities, a trait shared by several DPANN archaea.

Covid-19: Systems Transdisciplinary Generalization, Technical and Technological Ideas, and Solutions

Aim/Purpose: The Covid-19 pandemic has created many adverse effects. It overloads the healthcare system, causes deaths, and angers some at anti-covid restrictions. This study examines the feasibility of using technical and technological ideas to overcome these effects. The solution is based on new knowledge about the virus, its nature, formation, and activation in the environment. Background: The rapid spread of a new coronavirus infection is taking place against the background of a lack of time required to create new treatment scenarios for the disease, development, production, and vaccine safety research. In such a situation, it became necessary to gain this time for organizing and conducting events that could reduce the burden on the healthcare system. Methodology: The science that studies the morphology, physiology, genetics, ecology, and evolution of viruses is virology. The modern development of virology is moving towards a more accurate and comprehensive description of the mechanisms of interaction of viruses with the host organism. This contributed to the emergence of genomics, transcriptomics, proteomics, and immunomics. However, in virology, there is no particular discipline that sets itself three fundamental goals: to substantiate a single concept of the emergence of viruses; to study the natural mechanisms of formation of virus molecules in the environment; to describe the natural mechanisms of activation of certain viruses in the environment that cause viral pandemics. As a result, there are many articles among the published scientific articles on viruses dealing with the mechanisms of interaction of viruses with the host organism. However, there are no articles on the natural mechanisms of formation and activation of certain viruses in the environment. In the absence of such specialized articles, we were forced to use the method of systems transdisciplinary generalization of disciplinary knowledge to achieve our article’s purpose. Generalization created new knowledge about the nature of viruses, about the mechanisms of their formation and activation in the environment and cells of biological organisms. It is logical to assume that to synchronize the state of biological objects of all functional ensembles on the planet, it is necessary to create and activate appropriate “technological tools.” We have suggested and proved that RNA viruses play the role of such tools. Piezoelectricity activates viruses. It occurs during the compression and stretching of sedimentary rocks and bases of continental plates in different territories. Contribution: The systems transdisciplinary generalization of the knowledge of scientific disciplines made it possible to edit the concept of viruses, to eliminate stereotypes that arose due to the use of unsuccessful analogies. As a result of this generalization, it was possible to prove that viruses are not intracellular parasites. The virus is a “technological tool” of the planetary organizing component. This “tool” aims to correct the genetic programs of organisms of all functional ensembles (plants, animals, people), which will maintain the state of organisms and the parameters of their metabolism in changing environmental conditions. Findings: The viruses that triggered pandemics in the 20th century and early 21st century are RNA viruses. RNA molecules play the role of “technological tools” that the planetary organizing component uses to carry out short-term and long-term adjustments and constant support of the genetic programs of biological organisms. Therefore, in such a situation, it is advisable to talk not about the fight against the virus but only about eliminating the negative manifestations of the Covid-19 pandemic: reducing the number of people in need of emergency hospitalization, eliminating cases of the acute course of the disease and deaths. It is proposed to use certain technical and technological ideas and solutions to eliminate these negative manifestations. Recommendation for Researchers: This paper recommends that researchers use new interdisciplinary and transdisciplinary approaches. They challenge assumptions and conclusions about the nature of viruses, and the mechanisms of their formation and activation in the environment can initiate. Such new research might describe the mechanisms that form and activate viruses in the environment and the body’s cells. They also might provide practical use of this knowledge to eliminate the multiple speculations and fears that arise against the background of reports of the likely appearance of more deadly viruses and viral infections. Future Research: The results of a systems transdisciplinary generalization of disciplinary knowledge about the nature and purpose of viruses are essential for expanding the horizon of the scientific worldview. Future fundamental research on the mechanisms of objective organizing constituents, a general description given in this article, will contribute to a deeper understanding of chemical and biological evolution mechanisms in which modern humanity is involved. In due time, such an understanding will allow a new look at the existing scenarios of the world socio-economic order, explore and describe new principles of sustainable development of society.

Neuroendocrinology of Stress and Addiction

The stress response evolved as a series of neural and endocrine mechanisms that protect the host organism from threats to homeostasis. Repeated use of psychotropic drugs can lead to the development of tolerance (i.e., decreased drug activity at a given dose) and drug dependence, as indicated by withdrawal syndromes following drug abstinence. Drug withdrawal is often overtly stressful, although acute drug exposure may also represent a threat to homeostasis. This article explores the neuroendocrine effects of drugs of abuse and some of the ways in which stress and appetitive mechanisms interact.

Hide-and-Seek: A Game Played between Parasitic Protists and Their Hosts

After invading the host organism, a battle occurs between the parasitic protists and the host’s immune system, the result of which determines not only whether and how well the host survives and recovers, but also the fate of the parasite itself. The exact weaponry of this battle depends, among others, on the parasite localisation. While some parasitic protists do not invade the host cell at all (extracellular parasites), others have developed successful intracellular lifestyles (intracellular parasites) or attack only the surface of the host cell (epicellular parasites). Epicellular and intracellular protist parasites have developed various mechanisms to hijack host cell functions to escape cellular defences and immune responses, and, finally, to gain access to host nutrients. They use various evasion tactics to secure the tight contact with the host cell and the direct nutrient supply. This review focuses on the adaptations and evasion strategies of parasitic protists on the example of two very successful parasites of medical significance, Cryptosporidium and Leishmania, while discussing different localisation (epicellular vs. intracellular) with respect to the host cell.

Calcium-Responsive Diguanylate Cyclase CasA Drives Cellulose-Dependent Biofilm Formation and Inhibits Motility in Vibrio fischeri

Biofilm formation and motility are often critical behaviors for bacteria to colonize a host organism. Vibrio fischeri is the exclusive colonizer of its host’s symbiotic organ and requires both biofilm formation and motility to initiate successful colonization, providing a relatively simple model to explore complex behaviors. In this study, we determined how the environmental signal calcium alters bacterial behavior through production of the signaling molecule c-di-GMP.

Alveolar Regeneration in COVID-19 Patients: A Network Perspective

A viral infection involves entry and replication of viral nucleic acid in a host organism, subsequently leading to biochemical and structural alterations in the host cell. In the case of SARS-CoV-2 viral infection, over-activation of the host immune system may lead to lung damage. Albeit the regeneration and fibrotic repair processes being the two protective host responses, prolonged injury may lead to excessive fibrosis, a pathological state that can result in lung collapse. In this review, we discuss regeneration and fibrosis processes in response to SARS-CoV-2 and provide our viewpoint on the triggering of alveolar regeneration in coronavirus disease 2019 (COVID-19) patients.

SCREENING OF COLLECTION STRAINS (COLLECTIONS) OF ENTOMOPATHOGENIC FUNGI AGAINST ASIAN LOCUSTS FOR SIGNS OF VIRULENCE

The article provides a preliminary screening of Asian locust larvae aged 2-3 years for the virulence of 25 isolates isolated from insects belonging to different systematic groups of fungi Beauveria bassiana. Five of the 25 strains showed high biological activity against larvae, (BCo1-14, BSc1-15, BSc2-15, BTr1-16, BPit-16) reaching a mortality rate of 90-100% 21 days after inoculation. The strains that have the best effect on the level and rate of mortality of the host organism are - BCo1-14, BSc1-15, BSc2-15, BTr1-16, BPit-16. The greatest biological activity was observed in the BSc1-15 strain, as the mortality rate of test organisms was only 100% within 15 days of exposure. The lowest activity was shown by the BCi4-14 strain in the range of 35.0-62.5%. At the same time, the mortality rate of Asian locust larvae in the control variant (without treatment) for 21 days was 15.0±2.88%. Thus, the proportion of highly toxic forms (80-100% lethality) in the total number of studied strains was not more than 44%, and the proportion of mildly toxic forms (less than 80% activity) was 56%.

Unique Peptide Signatures Of SARS-CoV-2 Against Human Proteome Reveal Variants’ Immune Escape And Infectiveness

SummarySARS-CoV-2 pandemic has emerged the necessity of the identification of sequences sites in viral proteome appropriate as antigenic sites and treatment targets. In the present study, we apply a novel approach for deciphering the virus-host organism interaction, by analyzing the Unique Peptides of the virus with a minimum amino acid sequence length defined as Core Unique Peptides (CrUPs) not of the virus per se, but against the entire proteome of the host organism. The result of this approach is the identification of the CrUPs of the virus itself, which do not appear in the host organism proteome. Thereby, we analyzed the SARS-CoV-2 proteome for identification of CrUPs against the Human Proteome and they are defined as C/H-CrUPs. We found that SARS-CoV-2 include 7.503 C/H-CrUPs, with the SPIKE_SARS2 being the protein with the highest density of C/H-CrUPs. Extensive analysis indicated that the P681R mutation produces new C/H-CrUPs around the R685 cleavage site, while the L452R mutation induces the loss of antigenicity of the NF9 peptide and the strong(er) binding of the virus to ACE2 receptor protein. The simultaneous existence of these mutations in variants like Delta results in the immune escape of the virus, its massive entrance into the host cell, a notable increase in virus formation, and its massive release and thus elevated infectivity.

Congenital Transmission of Apicomplexan Parasites: A Review

Apicomplexans are a group of pathogenic protists that cause various diseases in humans and animals that cause economic losses worldwide. These unicellular eukaryotes are characterized by having a complex life cycle and the ability to evade the immune system of their host organism. Infections caused by some of these parasites affect millions of pregnant women worldwide, leading to various adverse maternal and fetal/placental effects. Unfortunately, the exact pathogenesis of congenital apicomplexan diseases is far from being understood, including the mechanisms of how they cross the placental barrier. In this review, we highlight important aspects of the diseases caused by species of Plasmodium, Babesia, Toxoplasma, and Neospora, their infection during pregnancy, emphasizing the possible role played by the placenta in the host-pathogen interaction.

The efficacy of specific immunocorrection drugs against ovine oestrosis

The purpose of the research is to characterize the effect of specific immunocorrection drugs on the survival rate of the sheep botfly larvae and the immune response of the host organism. Materials and methods. Three variants of laboratory samples of specific immunocorrection drugs against sheep oestrosis have been developed based on water-soluble proteins of Oestrus ovis L. and Lucilia serricata Mg. larvae. The studies were carried out on 12 test and 3 control groups of lambs born in the current year artificially infected with 80 larvae of the sheep botfly. Fourteen days before infection, the test lambs were immunized with the prepared drugs. The drugs were injected subcutaneously in various doses (2–6 ml) and repeatedly (1–3) or by a single intranasal irrigation at a dose of 10 ml per animal. The efficacy was evaluated for the early (July – September) and summer-spring (August – April) periods of parasitism. In the test and control animals, we determined specific antibodies (JgG), stable E-rosette-forming cells (sE-RFC) and antigen-reactive (AR-RFC) T-lymphocytes. Results and discussion. The tested specific immunocorrection drugs based on somatic proteins of the sheep botfly and the sheep green bottle larvae have a pronounced protective effect against ovine oestrosis. In experiments, being affected by various drug variants, 44.6–99.1% of the sheep botfly larvae died in the early period of parasitism, and 22.6–88.1% of the sheep botfly larvae died in the summer-spring period. Subcutaneously injected drugs stimulate the produced specific antibodies and activate the effector function of the T-cell immune system to a greater extent than intranasal irrigation.