22 pages, 10298 KiB  
Review
Crucial Role of Central Nervous System as a Viral Anatomical Compartment for HIV-1 Infection
by Ana Borrajo 1,2,*, Valentina Svicher 1, Romina Salpini 1, Michele Pellegrino 3 and Stefano Aquaro 3
1 Department of Experimental Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
2 Department of Microbiology and Parasitology, Faculty of Pharmacy, Complutense University of Madrid, 28040 Madrid, Spain
3 Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, Italy
Microorganisms 2021, 9(12), 2537; https://doi.org/10.3390/microorganisms9122537 - 8 Dec 2021
Cited by 11 | Viewed by 3660
Abstract
The chronic infection established by the human immunodeficiency virus 1 (HIV-1) produces serious CD4+ T cell immunodeficiency despite the decrease in HIV-1 ribonucleic acid (RNA) levels and the raised life expectancy of people living with HIV-1 (PLWH) through treatment with combined antiretroviral therapies [...] Read more.
The chronic infection established by the human immunodeficiency virus 1 (HIV-1) produces serious CD4+ T cell immunodeficiency despite the decrease in HIV-1 ribonucleic acid (RNA) levels and the raised life expectancy of people living with HIV-1 (PLWH) through treatment with combined antiretroviral therapies (cART). HIV-1 enters the central nervous system (CNS), where perivascular macrophages and microglia are infected. Serious neurodegenerative symptoms related to HIV-associated neurocognitive disorders (HAND) are produced by infection of the CNS. Despite advances in the treatment of this infection, HAND significantly contribute to morbidity and mortality globally. The pathogenesis and the role of inflammation in HAND are still incompletely understood. Principally, growing evidence shows that the CNS is an anatomical reservoir for viral infection and replication, and that its compartmentalization can trigger the evolution of neurological damage and thus make virus eradication more difficult. In this review, important concepts for understanding HAND and neuropathogenesis as well as the viral proteins involved in the CNS as an anatomical reservoir for HIV infection are discussed. In addition, an overview of the recent advancements towards therapeutic strategies for the treatment of HAND is presented. Further neurological research is needed to address neurodegenerative difficulties in people living with HIV, specifically regarding CNS viral reservoirs and their effects on eradication. Full article
(This article belongs to the Special Issue Molecular and Therapeutic Aspects of Viral Infections)
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17 pages, 4069 KiB  
Article
Immunocompetent Mice Infected by Two Lineages of Dengue Virus Type 2: Observations on the Pathology of the Lung, Heart and Skeletal Muscle
by Fernanda Cunha Jácome 1,*, Gabriela Cardoso Caldas 1, Arthur da Costa Rasinhas 1, Ana Luisa Teixeira de Almeida 1, Daniel Dias Coutinho de Souza 1, Amanda Carlos Paulino 1, Marcos Alexandre Nunes da Silva 1, Derick Mendes Bandeira 1, Ortrud Monika Barth 1, Flavia Barreto dos Santos 2,† and Debora Ferreira Barreto-Vieira 1,†
1 Laboratory of Viral Morphology and Morphogenesis, Instituto Oswaldo Cruz, Fiocruz, Avenida Brasil 4365, Rio de Janeiro 21040-900, Brazil
2 Laboratory of Viral Immunology, Instituto Oswaldo Cruz, Fiocruz, Avenida Brasil 4365, Rio de Janeiro 21040-900, Brazil
Those authors contributed equally to the work.
Microorganisms 2021, 9(12), 2536; https://doi.org/10.3390/microorganisms9122536 - 8 Dec 2021
Cited by 8 | Viewed by 2968
Abstract
Dengue virus (DENV) infection by one of the four serotypes (DENV-1 to 4) may result in a wide spectrum of clinical manifestations, with unpredictable evolution and organ involvement. Due to its association with severe epidemics and clinical manifestations, DENV-2 has been substantially investigated. [...] Read more.
Dengue virus (DENV) infection by one of the four serotypes (DENV-1 to 4) may result in a wide spectrum of clinical manifestations, with unpredictable evolution and organ involvement. Due to its association with severe epidemics and clinical manifestations, DENV-2 has been substantially investigated. In fact, the first emergence of a new lineage of the DENV-2 Asian/American genotype in Brazil (Lineage II) in 2008 was associated with severe cases and increased mortality related to organ involvement. A major challenge for dengue pathogenesis studies has been a suitable animal model, but the use of immune-competent mice, although sometimes controversial, has proven to be useful, as histological observations in infected animals reveal tissue alterations consistent to those observed in dengue human cases. Here, we aimed to investigate the outcomes caused by two distinct lineages of the DENV-2 Asian/American genotype in the lung, heart and skeletal muscle tissues of infected BALB/c mice. Tissues were submitted to histopathology, immunohistochemistry, histomorphometry and transmission electron microscopy (TEM) analysis. The viral genome was detected in heart and skeletal muscle samples. The viral antigen was detected in cardiomyocytes and endothelial cells of heart tissue. Heart and lung tissue samples presented morphological alterations comparable to those seen in dengue human cases. Creatine kinase serum levels were higher in mice infected with both lineages of DENV-2. Additionally, statistically significant differences, concerning alveolar septa thickening and heart weight, were observed between BALB/c mice infected with both DENV-2 lineages, which was demonstrated to be an appropriate experimental model for dengue pathogenesis studies on lung, heart and skeletal muscle tissues. Full article
(This article belongs to the Special Issue Arboviruses: Diagnostic, Phylogeny and Interactions)
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1 pages, 153 KiB  
Correction
Correction: Rainer et al. The Influence of Above-Ground Herbivory on the Response of Arctic Soil Methanotrophs to Increasing CH4 Concentrations and Temperatures. Microorganisms 2021, 9, 2080
by Edda M. Rainer 1,*, Christophe V. W. Seppey 1,2, Caroline Hammer 1, Mette M. Svenning 1 and Alexander T. Tveit 1
1 Department of Arctic and Marine Biology, UiT, The Arctic University of Norway, 9037 Tromsø, Norway
2 Institute of Environmental Sciences and Geography, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
Microorganisms 2021, 9(12), 2535; https://doi.org/10.3390/microorganisms9122535 - 8 Dec 2021
Cited by 1 | Viewed by 2205
Abstract
The authors wish to make the following corrections to this paper [...] Full article
(This article belongs to the Special Issue Microbial Communities in Methane Cycle in Arctic Region)
21 pages, 924 KiB  
Review
Vegetables and Fruit as a Reservoir of β-Lactam and Colistin-Resistant Gram-Negative Bacteria: A Review
by Widad Chelaghma 1, Lotfi Loucif 2,*, Mourad Bendahou 1 and Jean-Marc Rolain 3,4
1 Laboratoire de Microbiologie Appliquée à l’Agroalimentaire au Biomédical et à l’Environnement, Département de Biologie, Faculté des Sciences de la Nature et de la Vie, des Sciences de la Terre et l’Univers, Université Abou Bekr Belkaid, Tlemcen 13000, Algeria
2 Laboratoire de Biotechnologie des Molécules Bioactives et de la Physiopathologie Cellulaire (LBMBPC), Faculté des Sciences de la Nature et de la Vie, Université de Batna 2, Batna 05000, Algeria
3 Microbes, Evolution, Phylogénie et Infection (MEPHI), Institut de Recherche pour le Développement (IRD), Faculté de Médecine et de Pharmacie, Aix-Marseille Université, 13000 Marseille, France
4 IHU Méditerranée Infection, Assistance Publique des Hôpitaux de Marseille, 13000 Marseille, France
Microorganisms 2021, 9(12), 2534; https://doi.org/10.3390/microorganisms9122534 - 8 Dec 2021
Cited by 22 | Viewed by 4069
Abstract
Antibacterial resistance is one of the 2019 World Health Organization’s top ten threats to public health worldwide. Hence, the emergence of β-lactam and colistin resistance among Gram-negative bacteria has become a serious concern. The reservoirs for such bacteria are increasing not only in [...] Read more.
Antibacterial resistance is one of the 2019 World Health Organization’s top ten threats to public health worldwide. Hence, the emergence of β-lactam and colistin resistance among Gram-negative bacteria has become a serious concern. The reservoirs for such bacteria are increasing not only in hospital settings but in several other sources, including vegetables and fruit. In recent years, fresh produce gained important attention due to its consumption in healthy diets combined with a low energy density. However, since fresh produce is often consumed raw, it may also be a source of foodborne disease and a reservoir for antibiotic resistant Gram-negative bacteria including those producing extended-spectrum β-lactamase, cephalosporinase and carbapenemase enzymes, as well as those harboring the plasmid-mediated colistin resistance (mcr) gene. This review aims to provide an overview of the currently available scientific literature on the presence of extended-spectrum β-lactamases, cephalosporinase, carbapenemase and mcr genes in Gram-negative bacteria in vegetables and fruit with a focus on the possible contamination pathways in fresh produce. Full article
(This article belongs to the Section Food Microbiology)
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10 pages, 1998 KiB  
Article
Influence of the Incubator as Direct Patient Environment on Bacterial Colonization of Neonates
by Isabel Lange 1,*, Birgit Edel 2, Kristin Dawczynski 3, Hans Proquitté 4, Mathias W. Pletz 1, Frank Kipp 1 and Claudia Stein 1
1 Institute for Infectious Diseases and Infection Control, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
2 Institute of Medical Microbiology, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
3 Department of Pediatrics Weimar, Sophien-und Hufeland Klinikum, Henry-van-de-Velde-Str. 1, 99425 Weimar, Germany
4 Unit of Neonatology, Department of Paediatrics, Jena University Hospital, Friedrich Schiller University Jena, 07747 Jena, Germany
Microorganisms 2021, 9(12), 2533; https://doi.org/10.3390/microorganisms9122533 - 7 Dec 2021
Cited by 4 | Viewed by 3204
Abstract
Background: Preventing healthcare-associated infections (HAI) in neonatal intensive care units is a challenge of highest priority. For further insight into the incubator as direct patient environment and potential source for contamination, we present data correlating microbiological samples of very low birthweight infants in [...] Read more.
Background: Preventing healthcare-associated infections (HAI) in neonatal intensive care units is a challenge of highest priority. For further insight into the incubator as direct patient environment and potential source for contamination, we present data correlating microbiological samples of very low birthweight infants in the form of colonization results of surveillance screenings with samples of their associated incubator in this study. Methods: Samples were taken via rectal and throat swabs of neonates as well as Polywipe® sponges for the incubator. If the same bacterial species was found in corresponding neonate and incubator samples, whole genome sequencing via Illumina technology was performed. Results: 52 microbiological species matches were found, and 30 matches were sequenced where we found 26 clonal pairs (12 E. faecalis, 10 S. aureus, 2 E. coli, 1 E. cloacae, and 1 E. faecium). Conclusion: The combinations of measurements of weekly screenings swabs, probing of surfaces with Polywipes®, and whole genome sequencing showed transmissions of microorganism and risk for potential non-physiological colonization of neonatal infants. Full article
(This article belongs to the Special Issue Research in Hospital Infection Control)
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24 pages, 793 KiB  
Review
Lactic Acid Bacteria-Fermentable Cereal- and Pseudocereal-Based Beverages
by Małgorzata Ziarno * and Patrycja Cichońska
Department of Food Technology and Assessment, Institute of Food Science, Warsaw University of Life Sciences-SGGW (WULS-SGGW), 02-787 Warsaw, Poland
Microorganisms 2021, 9(12), 2532; https://doi.org/10.3390/microorganisms9122532 - 7 Dec 2021
Cited by 44 | Viewed by 7691
Abstract
Plant beverages are becoming more popular, and fermented cereal- or pseudocereal-based beverages are increasingly used as alternatives for fermented products made from cow milk. This review aimed to describe the basic components of cereal- or pseudocereal-based beverages and determine the feasibility of fermenting [...] Read more.
Plant beverages are becoming more popular, and fermented cereal- or pseudocereal-based beverages are increasingly used as alternatives for fermented products made from cow milk. This review aimed to describe the basic components of cereal- or pseudocereal-based beverages and determine the feasibility of fermenting them with lactic acid bacteria (LAB) to obtain products with live and active LAB cells and increased dietary value. The technology used for obtaining cereal- or pseudocereal-based milk substitutes primarily involves the extraction of selected plant material, and the obtained beverages differ in their chemical composition and nutritional value (content of proteins, lipids, and carbohydrates, glycemic index, etc.) due to the chemical diversity of the cereal and pseudocereal raw materials and the operations used for their production. Beverages made from cereals or pseudocereals are an excellent matrix for the growth of LAB, and the lactic acid fermentation not only produces desirable changes in the flavor of fermented beverages and the biological availability of nutrients but also contributes to the formation of functional compounds (e.g., B vitamins). Full article
(This article belongs to the Special Issue Advances in Microbial Biosynthesis)
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19 pages, 646 KiB  
Review
Toxoplasmosis: Current and Emerging Parasite Druggable Targets
by Rana El Hajj 1,†, Lina Tawk 2,†, Shaymaa Itani 3, Maguy Hamie 3, Jana Ezzeddine 2, Marwan El Sabban 4 and Hiba El Hajj 3,*
1 Department of Biological Sciences, Beirut Arab University, P.O. Box 11-5020, Riad El Solh, Beirut 1107 2809, Lebanon
2 Department of Medical Laboratory Sciences, Faculty of Health Sciences, University of Balamand, Beirut 1100 2807, Lebanon
3 Department of Experimental Pathology, Microbiology and Immunology, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon
4 Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon
These authors contributed equally to this work.
Microorganisms 2021, 9(12), 2531; https://doi.org/10.3390/microorganisms9122531 - 7 Dec 2021
Cited by 34 | Viewed by 7530
Abstract
Toxoplasmosis is a prevalent disease affecting a wide range of hosts including approximately one-third of the human population. It is caused by the sporozoan parasite Toxoplasma gondii (T. gondii), which instigates a range of symptoms, manifesting as acute and chronic forms [...] Read more.
Toxoplasmosis is a prevalent disease affecting a wide range of hosts including approximately one-third of the human population. It is caused by the sporozoan parasite Toxoplasma gondii (T. gondii), which instigates a range of symptoms, manifesting as acute and chronic forms and varying from ocular to deleterious congenital or neuro-toxoplasmosis. Toxoplasmosis may cause serious health problems in fetuses, newborns, and immunocompromised patients. Recently, associations between toxoplasmosis and various neuropathies and different types of cancer were documented. In the veterinary sector, toxoplasmosis results in recurring abortions, leading to significant economic losses. Treatment of toxoplasmosis remains intricate and encompasses general antiparasitic and antibacterial drugs. The efficacy of these drugs is hindered by intolerance, side effects, and emergence of parasite resistance. Furthermore, all currently used drugs in the clinic target acute toxoplasmosis, with no or little effect on the chronic form. In this review, we will provide a comprehensive overview on the currently used and emergent drugs and their respective parasitic targets to combat toxoplasmosis. We will also abridge the repurposing of certain drugs, their targets, and highlight future druggable targets to enhance the therapeutic efficacy against toxoplasmosis, hence lessening its burden and potentially alleviating the complications of its associated diseases. Full article
(This article belongs to the Special Issue The Molecular Life of Apicomplexa)
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15 pages, 1570 KiB  
Article
Molecular Variability and Host Distribution of ‘Candidatus Phytoplasma solani’ Strains from Different Geographic Origins
by Nicoletta Contaldo 1,*, Jelena Stepanović 2, Francesco Pacini 1, Assunta Bertaccini 1 and Bojan Duduk 2
1 Department of Agricultural and Food Sciences, Alma Mater Studiorum-University of Bologna, 40127 Bologna, Italy
2 Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia
Microorganisms 2021, 9(12), 2530; https://doi.org/10.3390/microorganisms9122530 - 7 Dec 2021
Cited by 7 | Viewed by 3222
Abstract
The knowledge of phytoplasma genetic variability is a tool to study their epidemiology and to implement an effective monitoring and management of their associated diseases. ‘Candidatus Phytoplasma solani’ is associated with “bois noir” disease in grapevines, and yellowing and decline symptoms in [...] Read more.
The knowledge of phytoplasma genetic variability is a tool to study their epidemiology and to implement an effective monitoring and management of their associated diseases. ‘Candidatus Phytoplasma solani’ is associated with “bois noir” disease in grapevines, and yellowing and decline symptoms in many plant species, causing serious damages during the epidemic outbreaks. The epidemiology of the diseases associated with this phytoplasma is complex and related to numerous factors, such as interactions of the host plant and insect vectors and spreading through infected plant propagation material. The genetic variability of ‘Ca. P. solani’ strains in different host species and in different geographic areas during the last two decades was studied by RFLP analyses coupled with sequencing on vmp1, stamp, and tuf genes. A total of 119 strains were examined, 25 molecular variants were identified, and the variability of the studied genes was linked to both geographic distribution and year of infection. The crucial question in ‘Ca. P. solani’ epidemiology is to trace back the epidemic cycle of the infections. This study presents some relevant features about differential strain distribution useful for disease monitoring and forecasting, illustrating and comparing the phytoplasma molecular variants identified in various regions, host species, and time periods. Full article
(This article belongs to the Section Plant Microbe Interactions)
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9 pages, 771 KiB  
Communication
High Potential for Anaerobic Microbial Sulfur Oxidation in Oil Sands Tailings Ponds
by Sebastian Stasik, Juliane Schmidt and Katrin Wendt-Potthoff *
Department of Lake Research, Helmholtz Centre for Environmental Research—UFZ, 04318 Leipzig, Germany
Microorganisms 2021, 9(12), 2529; https://doi.org/10.3390/microorganisms9122529 - 7 Dec 2021
Cited by 4 | Viewed by 2522
Abstract
The biogenic production of toxic H2S gas in sulfate-rich oil sands tailings ponds is associated with strong environmental concerns. Beside precipitation into sulfide minerals and chemical re-oxidation, microbial sulfur oxidation may catalyze sulfide re-cycling but potentially contributes to acid rock drainage [...] Read more.
The biogenic production of toxic H2S gas in sulfate-rich oil sands tailings ponds is associated with strong environmental concerns. Beside precipitation into sulfide minerals and chemical re-oxidation, microbial sulfur oxidation may catalyze sulfide re-cycling but potentially contributes to acid rock drainage (ARD) generation. To evaluate the microbial potential for sulfur oxidation, we conducted a microcosm-based pilot study with tailings of an active pond. Incubations were performed under oxic and anoxic conditions, with and without KNO3 as an electron acceptor and thiosulfate as a common substrate for microbial sulfur oxidation. The highest potentials of sulfur oxidation occurred in oxic assays (1.21 mmol L−1 day−1). Under anoxic conditions, rates were significantly lower and dominated by chemical transformation (0.09 mmol L−1 day−1; p < 0.0001). The addition of KNO3 to anoxic incubations increased microbial thiosulfate oxidation 2.5-fold (0.23 mmol L−1 day−1; p = 0.0474), with complete transformation to SO42− coupled to NO3 consumption, pointing to the activity of sulfur-oxidizing bacteria (SOB) under nitrate-reducing conditions. Importantly, in the presence of KNO3, a decrease in sedimentary sulfides was associated with an increase in S0, which indicates the potential for microbially mediated oxidation of sulfide minerals and ARD generation. Furthermore, the comparative analysis of sediments from other anthropogenic aquatic habitats demonstrated high similarities with respect to viable SOB counts and corresponding activity rates. Full article
(This article belongs to the Special Issue The Microbiology of Oil Sands Tailings)
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17 pages, 1575 KiB  
Article
Wine Spoilage Control: Impact of Saccharomycin on Brettanomyces bruxellensis and Its Conjugated Effect with Sulfur Dioxide
by Patrícia Branco 1,2,*,†, Rute Coutinho 2,†, Manuel Malfeito-Ferreira 2, Catarina Prista 2,* and Helena Albergaria 1,*
1 Unit of Bioenergy and Biorefinery, LNEG, Estrada do Paço do Lumiar, 22, 1649-038 Lisboa, Portugal
2 Linking Landscape, Environment, Agriculture and Food (LEAF), Associated Laboratory TERRA, Instituto Superior de Agronomia, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal
Contributed equally to the manuscript.
Microorganisms 2021, 9(12), 2528; https://doi.org/10.3390/microorganisms9122528 - 7 Dec 2021
Cited by 19 | Viewed by 3421
Abstract
The yeast Brettanomyces bruxellensis is one of the most dangerous wine contaminants due to the production of phenolic off-flavors such as 4-ethylphenol. This microbial hazard is regularly tackled by addition of sulfur dioxide (SO2). Nevertheless, B. bruxellensis is frequently found at [...] Read more.
The yeast Brettanomyces bruxellensis is one of the most dangerous wine contaminants due to the production of phenolic off-flavors such as 4-ethylphenol. This microbial hazard is regularly tackled by addition of sulfur dioxide (SO2). Nevertheless, B. bruxellensis is frequently found at low levels (ca 103 cells/mL) in finished wines. Besides, consumers health concerns regarding the use of sulfur dioxide encouraged the search for alternative biocontrol measures. Recently, we found that Saccharomyces cerevisiae secretes a natural biocide (saccharomycin) that inhibits the growth of different B. bruxellensis strains during alcoholic fermentation. Here we investigated the ability of S. cerevisiae CCMI 885 to prevent B. bruxellensis ISA 2211 growth and 4-ethylphenol production in synthetic and true grape must fermentations. Results showed that B. bruxellensis growth and 4-ethylphenol production was significantly inhibited in both media, although the effect was more pronounced in synthetic grape must. The natural biocide was added to a simulated wine inoculated with 5 × 102 cells/mL of B. bruxellensis, which led to loss of culturability and viability (100% dead cells at day-12). The conjugated effect of saccharomycin with SO2 was evaluated in simulated wines at 10, 12, 13 and 14% (v/v) ethanol. Results showed that B. bruxellensis proliferation in wines at 13 and 14% (v/v) ethanol was completely prevented by addition of 1.0 mg/mL of saccharomycin with 25 mg/L of SO2, thus allowing to significantly reduce the SO2 levels commonly used in wines (150–200 mg/L). Full article
(This article belongs to the Special Issue Microbial Grape and Wine Spoilage)
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19 pages, 1444 KiB  
Article
Mycobacterium abscessus Genetic Determinants Associated with the Intrinsic Resistance to Antibiotics
by Mylene Gorzynski 1,2, Tiana Week 1,3, Tiana Jaramillo 1,4, Elizaveta Dzalamidze 1,5 and Lia Danelishvili 1,*
1 Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA
2 Department of Biochemistry & Molecular Biology, Oregon State University, Corvallis, OR 97331, USA
3 Department of Bioengineering, College of Engineering, Oregon State University, Corvallis, OR 97331, USA
4 Department of Animal Sciences, College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331, USA
5 BioHealth Sciences, Department of Microbiology, College of Sciences, Oregon State University, Corvallis, OR 97331, USA
Microorganisms 2021, 9(12), 2527; https://doi.org/10.3390/microorganisms9122527 - 7 Dec 2021
Cited by 14 | Viewed by 4166
Abstract
Mycobacterium abscessus subsp. abscessus (MAB) is a fast-growing nontuberculous mycobacterium causing pulmonary infections in immunocompromised and immunocompetent individuals. The treatment of MAB infections in clinics is extremely challenging, as this organism is naturally resistant to most available antibiotics. There is limited knowledge on [...] Read more.
Mycobacterium abscessus subsp. abscessus (MAB) is a fast-growing nontuberculous mycobacterium causing pulmonary infections in immunocompromised and immunocompetent individuals. The treatment of MAB infections in clinics is extremely challenging, as this organism is naturally resistant to most available antibiotics. There is limited knowledge on the mechanisms of MAB intrinsic resistance and on the genes that are involved in the tolerance to antimicrobials. To identify the MAB genetic factors, including the components of the cell surface transport systems related to the efflux pumps, major known elements contributing to antibiotic resistance, we screened the MAB transposon library of 2000 gene knockout mutants. The library was exposed at either minimal inhibitory (MIC) or bactericidal concentrations (BC) of amikacin, clarithromycin, or cefoxitin, and MAB susceptibility was determined through the optical density. The 98 susceptible and 36 resistant mutants that exhibited sensitivity below the MIC and resistance to BC, respectively, to all three drugs were sequenced, and 16 mutants were found to belong to surface transport systems, such as the efflux pumps, porins, and carrier membrane enzymes associated with different types of molecule transport. To establish the relevance of the identified transport systems to antibiotic tolerance, the gene expression levels of the export related genes were evaluated in nine MAB clinical isolates in the presence or absence of antibiotics. The selected mutants were also evaluated for their ability to form biofilms and for their intracellular survival in human macrophages. In this study, we identified numerous MAB genes that play an important role in the intrinsic mechanisms to antimicrobials and further demonstrated that, by targeting components of the drug efflux system, we can significantly increase the efficacy of the current antibiotics. Full article
(This article belongs to the Special Issue Exploration of Intrinsic Resistance in Bacteria)
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14 pages, 7829 KiB  
Article
Toxoplasma gondii Genotypes Circulating in Serbia—Insight into the Population Structure and Diversity of the Species in Southeastern Europe, a Region of Intercontinental Strain Exchange
by Aleksandra Uzelac, Ivana Klun, Vladimir Ćirković, Neda Bauman, Branko Bobić, Tijana Štajner, Jelena Srbljanović, Olivera Lijeskić and Olgica Djurković-Djaković *
Group for Microbiology and Parasitology, Center of Excellence for Food- and Vector-Borne Zoonoses, Institute for Medical Research, University of Belgrade, National Institute of Republic of Serbia, 11129 Belgrade, Serbia
Microorganisms 2021, 9(12), 2526; https://doi.org/10.3390/microorganisms9122526 - 7 Dec 2021
Cited by 7 | Viewed by 3535
Abstract
In Europe, Toxoplasma gondii lineage II is dominant, and ToxoDB#1 the most frequently occurring genotype. The abundance of lineage III genotypes varies geographically and lineage I are rare, yet present in several regions of the continent. Data on the T. gondii population structure [...] Read more.
In Europe, Toxoplasma gondii lineage II is dominant, and ToxoDB#1 the most frequently occurring genotype. The abundance of lineage III genotypes varies geographically and lineage I are rare, yet present in several regions of the continent. Data on the T. gondii population structure in southeastern Europe (SEE) are scarce, yet necessary to appreciate the diversity of the species in Europe. To help fill this gap, we genotyped 67 strains from nine species of intermediate hosts in Serbia by MnPCR-RFLP, determined the population structure, and identified the genotypes using ToxoDB. A neighbor-joining tree was also constructed from the isolates genotyped on nine loci. While 42% of the total genotype population consisted of ToxoDB#1 and ToxoDB#2, variant genotypes of both lineages comprised 46% of the population in wildlife and 28% in domestic animals and humans. One genotype of Africa 4 lineage was detected in a human sample. Interestingly, the findings include one lineage III variant and one II/III recombinant isolate with intercontinental distribution, which appear to be moderately related to South American genotypes. Based on these findings, SEE is a region of underappreciated T. gondii genetic diversity and possible strain exchange between Europe and Africa. Full article
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15 pages, 2511 KiB  
Article
In Tuber Biocontrol of Potato Late Blight by a Collection of Phenazine-1-Carboxylic Acid-Producing Pseudomonas spp.
by Geneviève Léger 1, Amy Novinscak 2, Adrien Biessy 3, Simon Lamarre 1 and Martin Filion 3,*
1 Biology Department, Université de Moncton, Moncton, NB E1A 3E9, Canada
2 Agassiz Research and Development Centre, Agriculture and Agri-Food Canada, Agassiz, BC V0M 1A2, Canada
3 Saint-Jean-sur-Richelieu Research and Development Centre, Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu, QC J3B 7B5, Canada
Microorganisms 2021, 9(12), 2525; https://doi.org/10.3390/microorganisms9122525 - 7 Dec 2021
Cited by 13 | Viewed by 3098
Abstract
Phenazine-1-carboxylic acid (PCA) produced by plant-beneficial Pseudomonas spp. is an antibiotic with antagonistic activities against Phytophthora infestans, the causal agent of potato late blight. In this study, a collection of 23 different PCA-producing Pseudomonas spp. was confronted with P. infestans in potato [...] Read more.
Phenazine-1-carboxylic acid (PCA) produced by plant-beneficial Pseudomonas spp. is an antibiotic with antagonistic activities against Phytophthora infestans, the causal agent of potato late blight. In this study, a collection of 23 different PCA-producing Pseudomonas spp. was confronted with P. infestans in potato tuber bioassays to further understand the interaction existing between biocontrol activity and PCA production. Overall, the 23 strains exhibited different levels of biocontrol activity. In general, P. orientalis and P. yamanorum strains showed strong disease reduction, while P. synxantha strains could not effectively inhibit the pathogen’s growth. No correlation was found between the quantities of PCA produced and biocontrol activity, suggesting that PCA cannot alone explain P. infestans’ growth inhibition by phenazine-producing pseudomonads. Other genetic determinants potentially involved in the biocontrol of P. infestans were identified through genome mining in strains displaying strong biocontrol activity, including siderophores, cyclic lipopeptides and non-ribosomal peptide synthase and polyketide synthase hybrid clusters. This study represents a step forward towards better understanding the biocontrol mechanisms of phenazine-producing Pseudomonas spp. against potato late blight. Full article
(This article belongs to the Special Issue Interactions between Plant Beneficial Pseudomonas spp. and Their Host)
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15 pages, 1946 KiB  
Article
Succession Analysis of Gut Microbiota Structure of Participants from Long-Lived Families in Hechi, Guangxi, China
by Minhong Ren, He Li, Zhen Fu and Quanyang Li *
College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
Microorganisms 2021, 9(12), 2524; https://doi.org/10.3390/microorganisms9122524 - 7 Dec 2021
Cited by 30 | Viewed by 3836
Abstract
The gut microbiota structure has been proposed to be involved in longevity. In this study, trajectories of age-related changes in gut microbiota were analyzed by comparing the gut microbiota composition from long-lived families. A specific bacterial community pattern and signature taxa of long-lived [...] Read more.
The gut microbiota structure has been proposed to be involved in longevity. In this study, trajectories of age-related changes in gut microbiota were analyzed by comparing the gut microbiota composition from long-lived families. A specific bacterial community pattern and signature taxa of long-lived people were found in long-lived families, such as the enrichment of Enterobacteriaceae in all age groups and the higher abundances of Christensenellaceae, Verrucomicrobiaceae, Porphyromonadaceae, Rikenellaceae, Mogibacteriaceae, and Odoribacteraceae in long-lived elderly and the positive correlation between them. The cumulative abundance of the core microbiota was approximately stable along with age, but the genera and species in the core microbiota were rearranged with age, especially in Ruminococcaceae and Lachnospiraceae. Compared with the control group, the proportions of Lachnospiraceae, Roseburia, and Blautia were significantly higher in participants from the long-lived village, but their abundances gradually decreased along with age. Based on functional predictions, the proportions of pathways related to short-chain fatty acid metabolism, amino acid metabolism, and lipoic acid metabolism were significantly higher in the long-lived elderly compared with the offspring group. The trajectory of gut microbiota composition along with age in participants from long-lived families might reveal potential health-promoting metabolic characteristics, which could play an important role in healthy aging. Full article
(This article belongs to the Special Issue Microorganisms and Aging)
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Communication
Gastrointestinal Microbiota and Parasite-Fauna of Wild Dissostichus eleginoides Smitt, 1898 Captured at the South-Central Coast of Chile
by Italo Fernández 1, Patricio de Los Ríos-Escalante 2,3, Ariel Valenzuela 4, Paulina Aguayo 5,6, Carlos T. Smith 1, Apolinaria García-Cancino 1, Kimberly Sánchez-Alonso 1, Ciro Oyarzún 4 and Víctor L. Campos 1,*
1 Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, Chile
2 Departamento de Ciencias Biológicas y Químicas, Facultad de Recursos Naturales, Universidad Católica de Temuco, Temuco 4780000, Chile
3 Núcleo de Estudios Ambientales, Universidad Católica de Temuco, Temuco 4780000, Chile
4 Laboratorio de Piscicultura y Patología Acuática, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción 4070386, Chile
5 Institute of Natural Resources, Faculty of Veterinary Medicine and Agronomy, Universidad de Las Américas, Sede Concepción, Chacabuco 539, Concepción 3349001, Chile
6 EULA Environmental Sciences Center, Faculty of Environmental Sciences, Universidad de Concepción, Concepción 4070386, Chile
Microorganisms 2021, 9(12), 2522; https://doi.org/10.3390/microorganisms9122522 - 7 Dec 2021
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Abstract
Dissotichus eleginoides has a discontinuous circumpolar geographic distribution restricted to mountains and platforms, mainly in Subantarctic and Antarctic waters of the southern hemisphere, including the Southeast Pacific, Atlantic and Indian oceans and in areas surrounding the peninsular platforms of subantarctic islands. The aim [...] Read more.
Dissotichus eleginoides has a discontinuous circumpolar geographic distribution restricted to mountains and platforms, mainly in Subantarctic and Antarctic waters of the southern hemisphere, including the Southeast Pacific, Atlantic and Indian oceans and in areas surrounding the peninsular platforms of subantarctic islands. The aim of this work was to determine and characterize the gastrointestinal parasitic and microbial fauna of specimens of D. eleginoides captured in waters of the south-central zone of Chile. The magnitude of parasitism in D. eleginoides captured in waters of the south-central zone of Chile is variable, and the parasite richness is different from that reported in specimens from subantarctic environments. Next-generation sequencing (NGS) of the microbial community associated to intestine showed a high diversity, where Proteobacteria, Firmicutes, and Bacteriodetes were the dominant phyla. However, both parasitic and microbial structures can vary between fish from different geographic regions Full article
(This article belongs to the Section Environmental Microbiology)
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