The Split Personality of Beauveria bassiana: Understanding the Molecular Basis of Fungal Parasitism and Mutualism

Fungal pathogenicity toward insects has independently evolved several times, resulting in specialist and generalist pathogens, some of whom have maintained aspects of their previous lifestyles. Being able to grow as an endophyte (engaging in a mutualistic interaction with plants) or saprophyte (recycling nutrients back into the environment), the generalist (broad-host-range) fungus Beauveria bassiana does not need to rely on insect hosts to complete its life cycle. The diverse lifestyles of this fungus, saprophyte, pathogen, and symbiont, provide a unique system, with available genetic tools, to examine host-pathogen interactions, plant-fungus mutualistic relationships, and fungal development. This commentary highlights overlooked pathogenic and mutualistic aspects of B. bassiana that assist this fungus in shifting along the saprobe/parasite/mutualist continuum. Addressing these knowledge gaps and scrutinizing valuable players driving such a spectrum of ecological interactions will enrich our knowledge of fundamental environmental microbiology and help develop new approaches to pest control and sustainable farming

Repurposing ciclopirox as a pharmacological chaperone active against congenital erythropoietic porphyria.

138 p.La porfiria eritropoyética congénita es una enfermedad rara autosómica recesiva producida por una actividad deficiente en la uroporfirinógeno III sintasa, la cuarta enzima de la ruta biosintética del grupo hemo. La enfermedad afecta a diversos órganos, llegando a ser potencialmente peligroso para la vida, careciendo actualmente de tratamientos curativos. Bioquímicamente, las mutaciones hereditarias de mayor frecuencia reducen la estabilidad del enzima, alterando su homeostasis, que, en última instancia, reducen la producción de grupo hemo intracelular. Esto da como resultado la acumulación de subproductos de uroporfirina que se distribuyen y depositan por todos los tejidos, agravando la patología con síntomas tales como fotosensibilidad de la piel y lesiones cutáneas fototóxicas desfigurantes. En el presente trabajo, demostramos como el sintético antifúngico y microbiano fármaco comercial denominado ciclopirox, se asocia al enzima estabilizándolo. Ciclopirox asiste al enzima mediante unión alostética, distante del centro activo, sin afectar, por tanto, a su función catalítica. El fármaco es capaz de reestablecer la actividad in vitro, in cellula e in vivo, llegando incluso a aliviar la mayoría de los síntomas clínicos en un modelo de ratón bona fide de la enfermedad, actuando a concentraciones sub-tóxicas, estableciendo una nueva línea de intervención terapéutica contra la porfiria eritropoyética congénita. Aplicable a la mayoría de las mutaciones sin sentido perjudiciales que causan esta devastadora enfermedad.CICbioGUNE. Excelencia Severo Ocho

Repurposing ciclopirox as a pharmacological chaperone active against congenital erythropoietic porphyria.

138 p.La porfiria eritropoyética congénita es una enfermedad rara autosómica recesiva producida por una actividad deficiente en la uroporfirinógeno III sintasa, la cuarta enzima de la ruta biosintética del grupo hemo. La enfermedad afecta a diversos órganos, llegando a ser potencialmente peligroso para la vida, careciendo actualmente de tratamientos curativos. Bioquímicamente, las mutaciones hereditarias de mayor frecuencia reducen la estabilidad del enzima, alterando su homeostasis, que, en última instancia, reducen la producción de grupo hemo intracelular. Esto da como resultado la acumulación de subproductos de uroporfirina que se distribuyen y depositan por todos los tejidos, agravando la patología con síntomas tales como fotosensibilidad de la piel y lesiones cutáneas fototóxicas desfigurantes. En el presente trabajo, demostramos como el sintético antifúngico y microbiano fármaco comercial denominado ciclopirox, se asocia al enzima estabilizándolo. Ciclopirox asiste al enzima mediante unión alostética, distante del centro activo, sin afectar, por tanto, a su función catalítica. El fármaco es capaz de reestablecer la actividad in vitro, in cellula e in vivo, llegando incluso a aliviar la mayoría de los síntomas clínicos en un modelo de ratón bona fide de la enfermedad, actuando a concentraciones sub-tóxicas, estableciendo una nueva línea de intervención terapéutica contra la porfiria eritropoyética congénita. Aplicable a la mayoría de las mutaciones sin sentido perjudiciales que causan esta devastadora enfermedad.CICbioGUNE. Excelencia Severo Ocho

Tenebrionid secretions and a fungal benzoquinone oxidoreductase form competing components of an arms race between a host and pathogen

Entomopathogenic fungi and their insect hosts represent a model system for examining invertebrate-pathogen coevolutionary selection processes. Here we report the characterization of competing components of an arms race consisting of insect protective antimicrobial compounds and evolving fungal mechanisms of detoxification. The insect pathogenic fungus Beauveria bassiana has a remarkably wide host range; however, some insects are resistant to fungal infection. Among resistant insects is the tenebrionid beetle Tribolium castaneum that produces benzoquinone-containing defensive secretions. Reduced fungal germination and growth was seen in media containing T. castaneum dichloromethane extracts or synthetic benzoquinone. In response to benzoquinone exposure, the fungus expresses a 1,4-benzoquinone oxidoreductase, BbbqrA, induced >40-fold. Gene knockout mutants (ΔBbbqrA) showed increased growth inhibition, whereas B. bassiana overexpressing BbbqrA (Bb::BbbqrAO) displayed increased resistance to benzoquinone compared with wild type. Increased benzoquinone reductase activity was detected in wild-type cells exposed to benzoquinone and in the overexpression strain. Heterologous expression and purification of BbBqrA in Escherichia coli confirmed NAD(P)H-dependent benzoquinone reductase activity. The ΔBbbqrA strain showed decreased virulence toward T. castaneum, whereas overexpression of BbbqrA increased mortality versus T. castaneum. No change in virulence was seen for the ΔBbbqrA or Bb::BbbqrAO strains when tested against the greater wax moth Galleria mellonella or the beetle Sitophilus oryzae, neither of which produce significant amounts of cuticular quinones. The observation that artificial overexpression of BbbqrA results in increased virulence only toward quinone-secreting insects implies the lack of strong selection or current failure of B. bassiana to counteradapt to this particular host defense throughout evolution.Instituto de Investigaciones Bioquímicas de La Plat

Analysis of the Anti-Vaccine Movement in Social Networks: A Systematic Review

The aim of this study was to analyze social networks’ information about the anti-vaccine movement. A systematic review was performed in PubMed, Scopus, CINAHL and CUIDEN databases. The search equations were: “vaccine AND social network” and “vaccine AND (Facebook[title] OR Twitter[title] OR Instagram[title] OR YouTube[title])”. The final sample was n = 12, including only articles published in the last 10 years, in English or Spanish. Social networks are used by the anti-vaccine groups to disseminate their information. To do this, these groups use different methods, including bots and trolls that generate anti-vaccination messages and spread quickly. In addition, the arguments that they use focus on possible harmful effects and the distrust of pharmaceuticals, promoting the use of social networks as a resource for finding health-related information. The anti-vaccine groups are able to use social networks and their resources to increase their number and do so through controversial arguments, such as the economic benefit of pharmaceuticals or personal stories of children to move the population without using reliable or evidence-based content

Atmospheric emission changes and their economic impacts during the COVID-19 pandemic lockdown in Argentina

This work studied the emission changes and their economic effects during the Argentina’s COVID-19 pandemic lockdown. We have analyzed the atmospheric emissions of the main greenhouse gases (GHG: CO2, CH4, and N2O) and other pollutants (NOx, CO, NMVOC, SO2, PM10, PM2.5, and BC) from various sectors such as private road transport, freight, public transport, agriculture machines, thermal power plants, residential, commercial, and governmental from January 2005 to April 2020. We focused on the months with the greatest restrictions of COVID-19 pandemic in Argentina (March and April 2020). The results show emissions reduction up to 37% for PM10, PM2.5, and BC, consistent with observed from satellite images and up to 160% for NOx, CO, NMVOC, and SOx. However, the residential sector has increased their emissions by 8% for the same period. As a consequence, 3337 Gg of CO2eq of GHG emissions were reduced, corresponding to a 20% reduction compared to the same period in 2019. Besides, a 26% reduction in gross domestic product (GDP) was observed due to the COVID-19 pandemic. Our results show that each Tg of GHG reduction was associated to a 0.16% reduction of the GDP from the analyzed sectors. Thus, without a voluntary reduction in consumption associated to significant cultural and technological changes, reduction in GHG would still be associated with deepening inequalities and asymmetries between high and low consumption sectors (i.e., with better (lesser) education, health, and job opportunities), even within countries and cities.Fil: Bolaño Ortiz, Tomas Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional; ArgentinaFil: Puliafito, Salvador Enrique. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Berná Peña, Lucas Luciano. Universidad Tecnológica Nacional; Argentina. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Pascual Flores, Romina María. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional; ArgentinaFil: Urquiza, Josefina. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Camargo Caicedo, Yiniva. Universidad del Magdalena; Colombi

Genetic analyses place most Spanish isolates of Beauveria bassiana in a molecular group with word-wide distribution

<p>Abstract</p> <p>Background</p> <p>The entomopathogenic anamorphic fungus <it>Beauveria bassiana </it>is currently used as a biocontrol agent (BCA) of insects. Fifty-seven <it>Beauveria bassiana </it>isolates -53 from Spain- were characterized, integrating group I intron insertion patterns at the 3'-end of the nuclear large subunit ribosomal gene (LSU rDNA) and elongation factor 1-alpha (EF1-α) phylogenetic information, in order to assess the genetic structure and diversity of this Spanish collection of <it>B. bassiana</it>.</p> <p>Results</p> <p>Group I intron genotype analysis was based on the four highly conserved insertion sites of the LSU (Ec2653, Ec2449, Ec2066, Ec1921). Of the 16 possible combinations/genotypes, only four were detected, two of which were predominant, containing 44 and 9 members out of 57 isolates, respectively. Interestingly, the members of the latter two genotypes showed unique differences in their growth temperatures. In follow, EF1-α phylogeny served to classify most of the strains in the <it>B. bassiana s.s</it>. (<it>sensu stricto</it>) group and separate them into 5 molecular subgroups, all of which contained a group I intron belonging to the IC1 subtype at the Ec1921 position. A number of parameters such as thermal growth or origin (host, geographic location and climatic conditions) were also examined but in general no association could be found.</p> <p>Conclusion</p> <p>Most Spanish <it>B. bassiana </it>isolates (77.2%) are grouped into a major phylogenetic subgroup with word-wide distribution. However, high phylogenetic diversity was also detected among Spanish isolates from close geographic zones with low climatic variation. In general, no correlation was observed between the molecular distribution and geographic origin or climatic characteristics where the Spanish <it>B. bassiana </it>isolates were sampled.</p