Ecological Divergence Within the Enterobacterial Genus Sodalis: From Insect Symbionts to Inhabitants of Decomposing Deadwood

The bacterial genus Sodalis is represented by insect endosymbionts as well as free-living species. While the former have been studied frequently, the distribution of the latter is not yet clear. Here, we present a description of a free-living strain, Sodalis ligni sp. nov., originating from decomposing deadwood. The favored occurrence of S. ligni in deadwood is confirmed by both 16S rRNA gene distribution and metagenome data. Pangenome analysis of available Sodalis genomes shows at least three groups within the Sodalis genus: deadwood-associated strains, tsetse fly endosymbionts and endosymbionts of other insects. This differentiation is consistent in terms of the gene frequency level, genome similarity and carbohydrate-active enzyme composition of the genomes. Deadwood-associated strains contain genes for active decomposition of biopolymers of plant and fungal origin and can utilize more diverse carbon sources than their symbiotic relatives. Deadwood-associated strains, but not other Sodalis strains, have the genetic potential to fix N2, and the corresponding genes are expressed in deadwood. Nitrogenase genes are located within the genomes of Sodalis, including S. ligni, at multiple loci represented by more gene variants. We show decomposing wood to be a previously undescribed habitat of the genus Sodalis that appears to show striking ecological divergence

Replacement of native vegetation alters the soil microbial structure in the Pampa biome

Land use change is one of the the major factors related to soil degradation and alterations in soil microbial diversity and structure. In this study, we aimed to evaluate the microbial shifts caused by deforestation of a small area of a natural forest for the introduction of a pasture in the Brazilian Pampa. The microbial abundance and structure were evaluated by molecular approaches based on quantitative Polymerase Chain Reaction (qPCR) and Ribosomal Intergenic Spacer Analysis (RISA). The microbial communities did not present significant quantitative differences, but the environmental impact caused by deforestation changed the structure of the bacterial and archaeal communities. Taking into account the percentage of shared OTUs (operational taxonomic units) of each domain evaluated, we concluded that the domain Bacteria were more influenced by the deforestation than the Archaea. A total of 22 % of bacterial OTUs and 50 % of the archaeal OTUs were shared between forest and grassland leading us to conclude that the environment evaluated presented a core microbial community that did not suffer modification caused by land use change

Detection of Horizontal Gene Transfers from Phylogenetic Comparisons

Bacterial phylogenies have become one of the most important challenges for microbial ecology. This field started in the mid-1970s with the aim of using the sequence of the small subunit ribosomal RNA (16S) tool to infer bacterial phylogenies. Phylogenetic hypotheses based on other sequences usually give conflicting topologies that reveal different evolutionary histories, which in some cases may be the result of horizontal gene transfer events. Currently, one of the major goals of molecular biology is to understand the role that horizontal gene transfer plays in species adaptation and evolution. In this work, we compared the phylogenetic tree based on 16S with the tree based on dszC, a gene involved in the cleavage of carbon-sulfur bonds. Bacteria of several genera perform this survival task when living in environments lacking free mineral sulfur. The biochemical pathway of the desulphurization process was extensively studied due to its economic importance, since this step is expensive and indispensable in fuel production. Our results clearly show that horizontal gene transfer events could be detected using common phylogenetic methods with gene sequences obtained from public sequence databases

Relations of friendship and online games practice: an exploratory study with teenagers

Considering the impact of technological progress on social contacts, this study investigated the relationship between the practice of online games and friendship among 110 high school students from public and private schools. We elaborated and applied a questionnaire that addressed issues such as contact and communication, intimacy and closeness, satisfaction, social support and commitment. The results indicated that some characteristics of friendship relations in face-to-face situations show up in the relations between players in the online environment, that friendship in the context of online gaming seems to be organized around social support, and that the kind of support changes depending on the configuration of the environment in which the friendship develops.Keywords: friendship; adolescence; interpersonal relationship; online games. Considerando o progresso tecnológico e a repercussão dos mesmos nos contatos sociais, o presente estudo investigou a relação entre a prática de jogos online e a amizade em um grupo de 110 estudantes do Ensino Médio de escolas públicas e privadas. Para tanto, elaborou-se e aplicou-se um questionário que abordou aspectos como contato e comunicação, intimidade e proximidade, satisfação, apoio social e compromisso. Os resultados indicaram que algumas características das relações de amizade em situações presenciais comparecem nas relações entre os jogadores no ambiente online, que a amizade no contexto do jogo online parece organizar-se em torno do apoio social, e que o tipo de apoio sofre variações em função da configuração do ambiente em que a amizade se desenvolve.Palavras-chave: amizade; adolescência; relacionamento interpessoal; jogos online.

Telemedicine and molecular Sars-CoV-2 early detection to face the COVID-19 pandemic

The COVID-19 pandemic brought a series of challenges to the academic community. Social distancing measures imposed the interruption of face-to-face activities besides the implementation of remote work and online classes. For safe and gradual return, the monitoring of individuals, quick detection of infection, contact tracing, and isolation of those infected became essential. In this sense, we developed strategies to face the pandemic at the Federal University of Lavras (UFLA) - Brazil. A Telemedicine Program (TeleCovid) and the assemblage of a laboratory for SARS-CoV-2 molecular diagnosis (LabCovid) were essential measures for monitoring, preventing, and controlling outbreaks at the university. TeleCovid works with a team of students who guide and answer questions regarding COVID-19 and, when necessary, make the referral for online consultation with medical professionals. In the suspicion of SARS-CoV-2 infection, the doctor refers the patient for testing at LabCovid. LabCovid performs the sample collection using nasal swabs, followed by processing samples by the RT-qPCR method. We have placed all positive patients in isolation and tested their contacts. This approach meant that positive cases were identified early, thus avoiding outbreaks in different environments in face-to-face activities.Keyword: Covid-19; university, RT-qPC

Soil microbial diversity affects the plant-root colonization by arbuscular mycorrhizal fungi

Terrestrial plants establish symbiosis with arbuscular mycorrhizal fungi (AMF) to exchange water and nutrients. However, the extent to which soil biodiversity influences such association remains still unclear. Here, we manipulated the soil microbial diversity using a "dilution-to-extinction" approach in a controlled pot microcosm system and quantified the root length colonization of maize plants by the AMF Rhizophagus clarus. The experiment was performed by manipulating the soil microbiome within a native and foreign soil having distinct physicochemical properties. Overall, our data revealed significant positive correlations between the soil microbial diversity and AMF colonization. Most importantly, this finding opposes the diversity-invasibility hypothesis and highlights for a potential overall helper effect of the soil biodiversity on plant-AMF symbiosis

Aspectos cognitivos e metacognitivos do raciocínio de universitários com queixa de dificuldades de aprendizagem

O estudo propôs-se questionar quanto a possibilidade de se estabelecer correlações entre o desenvolvimento de certas noções operatórias, metacognição e dificuldades de aprendizagem em universitários em cursos da área de exatas. Entrevistamos cinco estudantes de engenharia de uma instituição pública de ensino superior do Espírito Santo. Todos frequentavam um programa de reforço escolar de uma das disciplinas básicas do núcleo comum das engenharias, oferecido pela instituição aos educandos com queixa de dificuldade de aprendizagem. Aplicamos a prova de flutuação de corpos, uma prova de correlação, e uma entrevista semiestruturada. Foi realizada uma análise do conteúdo tanto das provas quanto das entrevistas, através de uma adaptação das metodologias de análise já utilizadas e baseadas nos princípios da epistemologia genética. Os resultados indicaram, entre outros, que nenhum dos participantes atingiu o nível mais elevado nas respostas, que equivaleria à aplicação plena do raciocínio operatório formal; isso poderia justificar as dificuldades acadêmicas enfrentadas pelos participantes. Por outro lado, foi muito marcante a relativa ausência ou pouca variedade de estratégias de aprendizagem mencionadas pelos universitários pesquisados. O método clínico mostrou-se mais uma vez eficiente para o estudo da cognição de adultos, mas ainda carecemos de mais sistematizações quanto à análise dos resultados especialmente no que se refere à identificação e análise de modelos organizadores do pensamento. O presente estudo, mesmo exploratório e com as limitações devidas a tal característica, reforça a necessidade de que as instituições de ensino superior devam focar não somente a transmissão de conteúdos em suas políticas de permanência do estudante, mas também principalmente considerar aspectos psicossociais e de funcionamento cognitivo do adulto para poder atender com eficiência a essa questão

Facing the COVID-19 pandemic with science and practice

The COVID-19 pandemic has led to a health system crisis, deaths and socioeconomic hardship. In order to minimize the consequences of the COVID-19 pandemic in the municipality of Lavras, a partnership was developed between the Lavras City Hall and the Universidade Federal de Lavras (UFLA). The present study aimed to describe the main prevention measures proposed in Lavras and to evaluate the community's perception of the management model towards COVID-19. A public online questionnaire, with 20 multiple-choice questions, about the measures to confront covid was submitted to the Google Forms platform from April 22nd to April 30th, 2020. The data regarding the strategies carried out to deal with COVID-19 was obtained from the published municipal ordinances. During the eight days that the questionnaire was applied, a total of 8,874 respondents from Lavras were obtained. Among these respondents, 31.64% (2,808) were men, 68.15% (6,047) were women, and 0.21% (19) declared "another option". When the participants were asked whether they are respecting the social distance measures, 7,452 (84.1%) of them answered "yes."Also, a total of 57.4% of the participants reported that the social distancing measures compromised their family income. However, despite the impact of this economic compromise on these families, 93.82% of the respondents believe that the measures applied are important. When analyzing the questionnaire responses, it was noticeable that despite residents suffering negative economic consequences, there was great popular approval of preventive measures, such as social distancing and the use of masks. In addition, it was possible to notice the population's trust in the measures recommended by professionals at UFLA and the city hall, highlighting the importance of establishing contact between authorities and the population during decision making

BTW—Bioinformatics Through Windows: an easy-to-install package to analyze marker gene data

Recent advances in Next-Generation Sequencing (NGS) make comparative analyses of the composition and diversity of whole microbial communities possible at a far greater depth than ever before. This brings new challenges, such as an increased dependence on computation to process these huge datasets. The demand on system resources usually requires migrating from Windows to Linux-based operating systems and prior familiarity with command-line interfaces. To overcome this barrier, we developed a fully automated and easy-to-install package as well as a complete, easy-to-follow pipeline for microbial metataxonomic analysis operating in the Windows Subsystem for Linux (WSL)—Bioinformatics Through Windows (BTW). BTW combines several open-access tools for processing marker gene data, including 16S rRNA, bringing the user from raw sequencing reads to diversity-related conclusions. It includes data quality filtering, clustering, taxonomic assignment and further statistical analyses, directly in WSL, avoiding the prior need of migrating from Windows to Linux. BTW is expected to boost the use of NGS amplicon data by facilitating rapid access to a set of bioinformatics tools for Windows users. Moreover, several Linux command line tools became more reachable, which will enhance bioinformatics accessibility to a wider range of researchers and practitioners in the life sciences and medicine. BTW is available in GitHub (https://github.com/vpylro/BTW). The package is freely available for noncommercial users

Effect of microbial activity on penetrometer resistance and elastic modulus of soil at different temperatures

We explore the effect of microbial activity stimulated by root exudates on the penetrometer resistance of soil and its elastic modulus. This is important because it is a measure of the mechanical strength of soil and it correlates closely with the rate of elongation of roots. A sandy soil was incubated with a synthetic root exudate at different temperatures, for different lengths of time and with selective suppression of either fungi or bacteria. The shape of the temperature response of penetrometer resistance in soil incubated with synthetic exudate was typical of a poikilothermic temperature response. Both penetrometer resistance and small strain shear modulus had maximum values between 25 and 30°C. At temperatures of 20°C and less, there was little effect of incubation with synthetic root exudate on the small strain shear modulus, although penetrometer resistance did increase with temperature over this range (4–20°C). This suggests that in this temperature range the increase in penetrometer resistance was related to a greater resistance to plastic deformation. At higher temperatures (> 25°C) penetrometer resistance decreased. Analysis of the DNA sequence data showed that at 25°C the number of Streptomyces (Gram‐positive bacteria) increased, but selective suppression of either fungi or bacteria suggested that fungi have the greater role with respect to penetrometer resistance