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Tightly controlled response to oxidative stress; an important factor in the tolerance of Bacteroides fragilis Res. Microbiol. (IF 3.217) Pub Date : 2021-01-21 Mina Yekani; Hossein Bannazadeh Baghi; Sepideh Zununi Vahed; Hadi Ghanbari; Rasul Hosseinpur; Robab Azargun; Somayeh Azimi; Mohammad Yousef Memar
The exposure of B. fragilis to highly oxygenated tissues induces an oxidative stress due to a shift from the reduced condition of the gastrointestinal tract to an aerobic environment of host tissues. The potent and effective responses to reactive oxygen species (ROS) make the B. fragilis tolerant to atmospheric oxygen for several days. The response to oxidative stress in B. fragilis is a complicated
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Acyldepsipeptide activated ClpP1P2 macromolecule of Leptospira, an ideal Achilles’ heel to hamper the cell survival and deregulate ClpP proteolytic activity Res. Microbiol. (IF 3.217) Pub Date : 2021-01-15 Anusua Dhara; Md Saddam Hussain; Shankar Prasad Kanaujia; Manish Kumar
Antibiotic acyldepsipeptide (ADEP) targets the bacterial ClpP serine protease and can inhibit the growth of numerous bacterial species by activating/dysregulating the protease activity within the cell. The spirochete Leptospira interrogans harbors two ClpP isoforms (LepClpP1 and LepClpP2). Supplementation of ADEP in the Leptospira growth medium resulted in the inhibition of bacterial growth. The ADEP
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Proteomic comparison of biofilm vs. planktonic Staphylococcus epidermidis cells suggests key metabolic differences between these conditions Res. Microbiol. (IF 3.217) Pub Date : 2021-01-05 Sergio Martínez-García; Humberto Peralta; Gabriel Betanzos-Cabrera; Leslie Chavez-Galan; Sandra Rodríguez-Martínez; Mario E. Cancino-Diaz; Juan C. Cancino-Diaz
Previous studies have shown that biofilm-forming bacteria are deficient in tricarboxylic acid (TCA) cycle metabolites, suggesting a relationship between these cellular processes. In this work, we compared the proteomes of planktonic vs biofilm cells from a clinical strain of Staphylococcus epidermidis using LC-MS/MS. A total of 168 proteins were identified from both growth conditions. The biofilm cells
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Bacteriophages that infect Gram-negative bacteria as source of signal-arrest-release motif lysins Res. Microbiol. (IF 3.217) Pub Date : 2020-12-19 Marco Túlio Pardini Gontijo; Pedro Marcus Pereira Vidigal; Maryoris Elisa Soto Lopez; Marcelo Brocchi
Treatment of infections caused by multidrug-resistant (MDR) Gram-negative bacteria is challenging, a potential solution for which is the use of bacteriophage-derived lytic enzymes. However, the exogenous action of bacteriophage lysins against Gram-negative bacteria is hindered due to the presence of an impermeable outer membrane in these bacteria. Nevertheless, recent research has demonstrated that
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SopA inactivation or reduced expression is selected in intracellular Salmonella and contributes to systemic Salmonella infection Res. Microbiol. (IF 3.217) Pub Date : 2020-12-19 Shuangshuang Ma; Xiaoqian Liu; Shuai Ma; Lingyan Jiang
Pseudogenes are accumulated in host-restricted Salmonella enterica serovars, while pseudogenization is primarily regarded as a process that purge unnecessary genes from the genome. Here we showed that the inactivation of sopA, which encodes an effector of Salmonella pathogenicity island 1, in human-restricted S. enterica serovar Typhi (S. Ty) and Paratyphi A (S. PA) is under positive selection and
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Research on DnaA in the early days Res. Microbiol. (IF 3.217) Pub Date : 2020-11-25 Masamichi Kohiyama
The Escherichia coli chromosome is a circular double helix. DNA polymerase, therefore, cannot use it directly as a template for polymerization until it has first been unwound. The DnaA protein opens the chromosome at a unique and specific site (oriC), which allows the polymerase to begin DNA replication. François Jacob and Sydney Brenner predicted the existence of the initiator protein, DnaA, back
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Purification of membrane vesicles from Gram-positive bacteria using flow cytometry, after iodixanol density-gradient ultracentrifugation Res. Microbiol. (IF 3.217) Pub Date : 2020-11-18 Tadahiro Nasukawa; Ryosuke Sugimoto; Jumpei Uchiyama; Iyo Takemura-Uchiyama; Hironobu Murakami; Ken Fukuda; Shigenobu Matsuzaki; Masahiro Sakaguchi
Membrane vesicles (MVs) play biologically important roles in Gram-positive bacteria, and purification is essential for their study. Although high-performance flow cytometry has the capability to quantify and isolate specific small particles, it has not been examined for MV isolation. In this study, we used high-performance flow cytometry to analyze MV from Gram-positive bacteria, Staphylococcus aureus
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Evolution of gentamicin and arsenite resistance acquisition in Ralstonia pickettii water isolates Res. Microbiol. (IF 3.217) Pub Date : 2020-11-13 Pompeyo Ferro; Ivone Vaz-Moreira; Célia M. Manaia
Ralstonia pickettii are ubiquitous in water environments. Members of this species are frequently, but not always, resistant to both gentamicin and arsenite. Gentamicin and arsenite co-resistance and the putative molecular mechanisms were investigated. A group of 37 R. pickettii strains isolated from drinking water and hospital wastewater were characterized for gentamicin and arsenite resistance phenotypes
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Occurrence of filamentous fungi in drinking water: their role on fungal-bacterial biofilm formation Res. Microbiol. (IF 3.217) Pub Date : 2020-11-13 Tiago Barros Afonso; Lúcia Chaves Simões; Nelson Lima
Water is indispensable to life and safe and accessible supply must be available to all. The presence of microorganisms is a threat to this commitment. Biofilms are the main reservoir of microorganisms inside water distribution systems and they are extremely ecologically diverse. Filamentous fungi and bacteria can coexist inside these systems forming inter-kingdom biofilms. This review has the goal
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N6-methyladenine and epigenetic immunity of Deinococcus radiodurans Res. Microbiol. (IF 3.217) Pub Date : 2020-11-11 Suraj Joshi; Aman Kumar Ujaoney; Payel Ghosh; Deepti D. Deobagkar; Bhakti Basu
DNA methylation is ubiquitously found in all three domains of life. This epigenetic modification on adenine or cytosine residues serves to regulate gene expression or to defend against invading DNA in bacteria. Here, we report the significance of N6-methyladenine (6mA) to epigenetic immunity in D. radiodurans. Putative protein encoded by DR2267 ORF (Dam2DR) contributed 35% of genomic 6mA in D. radiodurans
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Cross-correlating analyses of mineral-associated microorganisms in an unsaturated packed bed flow-through column test; cell number, activity and EPS Res. Microbiol. (IF 3.217) Pub Date : 2020-09-21 Didi X. Makaula; Robert J. Huddy; Marijke A. Fagan-Endres; Susan T.L. Harrison
In heap bioleaching and waste-rock dumps, complex microbial communities exist in the flowing and interstitial liquid phases and mineral surface-associated biofilms, often embedded in extracellular polymeric substances (EPS). Microbial activity in the interstitial phase and mineral ore surface facilitates mineral degradation, resulting in either metal recovery or acidic, metal -bearing drainage from
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Effect of inoculum history, growth substrates and yeast extract addition on inhibition of Sulfobacillus thermosulfidooxidans by NaCl. Res. Microbiol. (IF 3.217) Pub Date : 2020-09-08 Dieu Huynh,Stefan R Kaschabek,Michael Schlömann
This study reports on the effect of inoculum history, growth substrates, and yeast extract on sodium chloride tolerance of Sulfobacillus thermosulfidooxidans DSM 9293T. The concentrations of NaCl for complete inhibition of Fe2+ oxidation by cells initially grown with ferrous iron sulfate, or tetrathionate, or pyrite as energy sources were 525 mM, 725 mM, and 800 mM, respectively. Noticeably, regardless
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Bioleaching of pyritic coal wastes: bioprospecting and efficiency of selected consortia. Res. Microbiol. (IF 3.217) Pub Date : 2020-09-03 Catherine Joulian,Viviana Fonti,Simon Chapron,Christopher G Bryan,Anne-Gwénaëlle Guezennec
Pyrite-bearing coal wastes are responsible of the formation of acid mine drainage (AMD), and their management to mitigate environmental impacts is a challenge to the coal mine industry in Europe and worldwide. The European CEReS project sought to develop a generic co-processing strategy to reuse and recycle coal wastes, based on removal of AMD generating potential through bioleaching. Chemolitoautotrophic
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Microbial community composition in iron deposits and manganese crusts formed in riverine environments around the Aso area in Japan Res. Microbiol. (IF 3.217) Pub Date : 2020-09-24 Shin-ichi Hirano; Yuki Ito; Shiro Tanaka; Toru Nagaoka; Takahiro Oyama
The Kurokawa river flowing through the Aso Caldera in Southwest Japan is influenced by groundwater containing high concentration of dissolved metals (Fe2+ and Mn2+) and is associated with orange deposits in the upstream and thick black crusts on the wall of artificial waterway tunnel with several km lengths in the midstream regions. X-ray fluorescence analysis revealed that the orange deposits contained
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Identification of a gene encoding a novel thiosulfate:quinone oxidoreductase in marine Acidithiobacillus sp. strain SH Res. Microbiol. (IF 3.217) Pub Date : 2020-10-05 Tadayoshi Kanao; Sultana Sharmin; Mirai Tokuhisa; Maho Otsuki; Kazuo Kamimura
Sulfur-oxidizing bacteria that are halophilic and acidophilic have gained interest because of their potential use in bioleaching operations in salt-containing environments. Acidithiobacillus sp. strain SH, which was previously identified as Acidithiobacillus thiooxidans based on its 16S rRNA gene sequence, is a chemolithoautotrophic marine bacterium exhibiting sodium chloride-stimulated thiosulfate-oxidizing
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Volatile organic compounds produced by Aureobasidium pullulans induce electrolyte loss and oxidative stress in Botrytis cinerea and Alternaria alternata Res. Microbiol. (IF 3.217) Pub Date : 2020-10-10 Sashika M. Yalage Don; Leigh M. Schmidtke; Joanna M. Gambetta; Christopher C. Steel
Aureobasidium pullulans is a yeast-like fungus that produces volatile organic compounds (VOCs) with antifungal properties. VOCs have the potential to trigger the production of intracellular reactive oxygen species (ROS), lipid peroxidation and electrolyte loss in microorganisms. The relationship among A. pullulans VOCs, induced ROS accumulation and electrolyte leakage was investigated in Botrytis cinerea
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High reduction of staphylococcal biofilm by aqueous extract from marine sponge-isolated Enterobacter sp. Res. Microbiol. (IF 3.217) Pub Date : 2020-10-10 Suzanne de Oliveira Nunes; Heloisa da Silva Rosa; Anna Luiza Bauer Canellas; Maria Teresa Villela Romanos; Katia R.N. dos Santos; Guilherme Muricy; Walter M.R. Oelemann; Marinella Silva Laport
Staphylococcus aureus and Staphylococcus epidermidis are among the most important bacterial species responsible for biofilm formation on indwelling medical devices, including orthopaedic implants. The increasing resistance to antimicrobials, partly attributed to the ability to form biofilms, is a challenge for the development of new antimicrobial agents. In this study, the cell-free supernatant obtained
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Signalling mechanisms involved in stress response to antifungal drugs Res. Microbiol. (IF 3.217) Pub Date : 2020-10-08 Ján Víglaš; Petra Olejníková
The emergence of antifungal resistance is a serious threat in the treatment of mycoses. The primary susceptible fungal cells may evolve a resistance after longer exposure to antifungal agents. The exposure itself causes stress condition, to which the fungus needs to adapt. This review provides detailed description of evolutionary conserved molecular mechanisms contributing to the adaptation response
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Comparative proteomics reveals essential mechanisms for osmotolerance in Gluconacetobacter diazotrophicus Res. Microbiol. (IF 3.217) Pub Date : 2020-10-06 Mariana Leandro; Leandro Andrade; Luciano Vespoli; Julia Moreira; Vivian Pimentel; Fabiano Soares; Lucas Passamani; Vanildo Silveira; Gonçalo de Souza Filho
Plant growth-promoting bacteria are a promising alternative to improve agricultural sustainability. Gluconacetobacter diazotrophicus is an osmotolerant bacterium able to colonize several plant species, including sugarcane, coffee, and rice. Despite its biotechnological potential, the mechanisms controlling such osmotolerance remain unclear. The present study investigated the key mechanisms of resistance
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Isolation, characterization, and efficacy of bacteriophages isolated against Citrobacter spp. an in vivo approach in a zebrafish model (Danio rerio). Res. Microbiol. (IF 3.217) Pub Date : 2020-09-10 Madhav Madurantakam Royam,Ramesh Nachimuthu
Citrobacter infections are becoming an increasingly significant health problem in aquaculture in South-Eastern countries. The objective of this study was to isolate and evaluate the potential of lytic bacteriophages against Citrobacter infections. TEM analysis revealed that the isolated phages Citrophage MRM19 and Citrophage MRM57 were identified to be Siphovirus and Podovirus family of the order Caudovirales
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An effective culturomics approach to study the gut microbiota of mammals. Res. Microbiol. (IF 3.217) Pub Date : 2020-09-06 André C Pereira,Mónica V Cunha
The microbial characterization of the mammal’s gut is an emerging research area, wherein culturomics methodologies applied to human samples are transposed to the animal context without improvement. In this work, using Egyptian mongoose as a model, we explore wet bench conditions to define an effective experimental design based on culturomics and DNA barcoding with potential application to different
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Biofilm formation by ST17 and ST19 strains of Streptococcus agalactiae. Res. Microbiol. (IF 3.217) Pub Date : 2020-09-05 Inês Silvestre,Maria José Borrego,Luísa Jordão
Bacterial biofilms are an important virulence factor with a vital role in evasion from the host immune system, colonization and infection. The aim of the present study was to evaluate in vitro the effects of three environmental factors (H+, glucose and human plasma) in biofilm formation, by carrier and invasive Streptococcus agalactiae strains of ST17 and ST19 sequence types, including DNase producers
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Isolation and characterization of a novel acidophilic zero-valent sulfur- and ferric iron-respiring Firmicute. Res. Microbiol. (IF 3.217) Pub Date : 2020-08-14 Roseanne Holanda,D Barrie Johnson
A novel, obligately anaerobic, acidophilic bacterium (strain I2511), isolated from sediment in an abandoned copper mine, was shown to couple the oxidation of organic electron donors to the reduction of both zero-valent sulfur and ferric iron in acidic media. The isolate was an obligate heterotroph that used a variety of organic compounds as electron donors and required yeast extract for growth. Alternative
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First insights to the microbial communities in the plant process water of the multi-metal Kevitsa mine. Res. Microbiol. (IF 3.217) Pub Date : 2020-08-13 Malin Bomberg,Hanna Miettinen,Benjamin Musuku,Päivi Kinnunen
Metallurgical processes demand large quantities of water. However, in many locations, water is becoming scarce and process water recycling is needed. Closing water loops can be challenging due to build-up of flotation chemicals, metal ions and microorganisms in the recycled water affecting the flotation performance. Here, we have characterized the microbial communities over a 2-month period in different
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Thiol-specific oxidant diamide downregulates whiA gene of Corynebacterium glutamicum, thereby suppressing cell division and metabolism. Res. Microbiol. (IF 3.217) Pub Date : 2020-08-01 Haeri Jeong,Jae-Hyun Lee,Younhee Kim,Heung-Shick Lee
The whiA (NCgl1527) gene from Corynebacterium glutamicum plays a crucial role during cell growth, and WhiA is recognized as the transcription factor for genes involved in cell division. In this study, we assessed the regulatory role of the gene in cell physiology. Transcription of the gene was specifically downregulated by the thiol-specific oxidant, diamide, and by heat stress. Cells exposed to diamide
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Study of the relationship between extracellular superoxide and glutathione production in batch cultures of Escherichia coli. Res. Microbiol. (IF 3.217) Pub Date : 2020-07-25 Galina V Smirnova,Aleksey V Tyulenev,Nadezda G Muzyka,Oleg N Oktyabrsky
Aerobically growing Escherichia coli generates superoxide flux into the periplasm via the oxidation of dihydromenaquinone and simultaneously carries out continuous transmembrane cycling of glutathione (GSH). Here we have shown that, under the conditions of a gradual decrease in dissolved oxygen (dO2), characteristic of batch culture, the global regulatory system ArcB/ArcA can play an important role
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Combined antimicrobial use of essential oils and bacteriocin bacLP17 as seafood biopreservative to control Listeria monocytogenes both in planktonic and in sessile forms. Res. Microbiol. (IF 3.217) Pub Date : 2020-07-25 Ramona Iseppi,Stefania Camellini,Carla Sabia,Patrizia Messi
The antilisterial activity of Thymus vulgaris, Salvia officinalis essential oils (EOs) and bacteriocin bacLP17 (previously isolated from seafood) was determined, using the compounds alone and in combination. The Disk Diffusion, Minimal Inhibitory Concentration (MIC) and Agar Well Diffusion assays were used to evaluate the effectiveness of the compounds against 12 Listeria monocytogenes in planktonic
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Quorum sensing: its role in microbial social networking. Res. Microbiol. (IF 3.217) Pub Date : 2020-06-24 Angkita Sharma,Pooja Singh,Bidyut Kr Sarmah,Shoma Paul Nandi
Twentieth century observed a huge paradigm shift in the field of sociobiology, which moved from social intelligence of animals to microbes. Quorum Sensing Molecules (QSMs) are the small chemical molecules, which establish the mode of communication among microbes, and is called Quorum Sensing (QS). These molecules are crucial for determining the decisions of large groups of cells, which is a density-dependent
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Effect of bile on growth and biofilm formation of non-typhoidal salmonella serovars isolated from seafood and poultry. Res. Microbiol. (IF 3.217) Pub Date : 2020-06-20 Akshatha Kotian,Vankadari Aditya,Kadeeja Jazeela,Iddya Karunasagar,Indrani Karunasagar,Vijaya Kumar Deekshit
Bacterial cells adopt various strategies to adapt themselves in diverse environmental conditions. Salmonella is one such bacteria with diverse mechanisms to survive, replicate and infect in wide host range. This study aims at investigating the biofilm-forming ability of multidrug-resistant and sensitive Salmonella serovars on exposure to bile. Antibiogram of all the isolates was determined by disk
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Auxin biosynthesis in the phytopathogenic fungus Leptosphaeria maculans is associated with enhanced transcription of indole-3-pyruvate decarboxylase LmIPDC2 and tryptophan aminotransferase LmTAM1. Res. Microbiol. (IF 3.217) Pub Date : 2020-06-12 Hana Leontovyčová,Lucie Trdá,Petre Ivanov Dobrev,Vladimír Šašek,Elise Gay,Marie-Hélène Balesdent,Lenka Burketová
Auxins are hormones that regulate growth and development in plants. Besides plants, various microorganisms also produce auxins. Here we investigate whether and how the phytopathogenic fungus Leptosphaeria maculans biosynthesizes auxins. We characterized the auxin profile of in vitro grown L. maculans. The culture was further supplied with the auxin biosynthetic-precursors tryptophan and tryptamine
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Function analysis of RNase E in the filamentous cyanobacterium Anabaena sp. PCC 7120. Res. Microbiol. (IF 3.217) Pub Date : 2020-06-23 Huaduo Yan,Yarui Cheng,Li Wang,Wenli Chen
RNase E is an endoribonuclease and plays a central role in RNA metabolism. Cyanobacteria, as ancient oxygen-producing photosynthetic bacteria, also contain RNase E homologues. Here, we introduced mutations into the S1 subdomain (F53A), the 5′-sensor subdomain (R160A), and the DNase I subdomain (D296A) according to the key activity sites of Escherichia coli RNase E. The results of degradation assays
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A transcriptional regulator, IscR, of Burkholderia multivorans acts as both repressor and activator for transcription of iron-sulfur cluster-biosynthetic isc operon. Res. Microbiol. (IF 3.217) Pub Date : 2020-07-03 Shouta Nonoyama,Kouhei Kishida,Keiichiro Sakai,Yuji Nagata,Yoshiyuki Ohtsubo,Masataka Tsuda
Bacterial iron-sulfur (Fe–S) clusters are essential cofactors for many metabolic pathways, and Fe–S cluster-containing proteins (Fe–S proteins) regulate the expression of various important genes. However, biosynthesis of such clusters has remained unknown in genus Burkholderia. Here, we clarified that Burkholderia multivorans ATCC 17616 relies on the ISC system for the biosynthesis of Fe–S clusters
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Formation and use of biogenic jarosite carrier for high-rate iron oxidising biofilms. Res. Microbiol. (IF 3.217) Pub Date : 2020-07-03 Sarita Ahoranta,Hanna Hulkkonen,Turkka Salminen,Pirjo Kuula,Jaakko A Puhakka,Aino-Maija Lakaniemi
Jarosite precipitates formed in iron oxidising bioreactors have been shown to harbour iron-oxidisers. The aim of this study was to develop an iron oxidising bioprocess where microorganisms are retained solely on biogenic jarosite particles. Based on preliminary experiments using a fluidised-bed bioreactor (FBR), the formed jarosite particles started to disintegrate and wash out at upflow velocities
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Efficient method for targeted gene disruption by homologous recombination in Mycobacterium avium subspecie paratuberculosis. Res. Microbiol. (IF 3.217) Pub Date : 2020-04-10 Maria Natalia Alonso,Wladimir Malaga,Michael Mc Neil,Mary Jackson,Maria Isabel Romano,Christophe Guilhot,María Paz Santangelo
Targeted gene disruption by homologous recombination, has been widely used in mycobacterium species to understand the genetic basis of virulence and persistence in the host and to develop efficacious potential live vaccines. However, in slow growing pathogenic mycobacteria as Mycobacterium avium subsp paratuberculosis (MAP), these methods have been inefficient, in part due to the low frequency of legitimate
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Antimicrobial peptides against drug resistant Mycobacterium abscessus. Res. Microbiol. (IF 3.217) Pub Date : 2020-03-18 Joas L da Silva,Shashank Gupta,Kenneth N Olivier,Adrian M Zelazny
Mycobacterium abscessus (MAB) comprise rapidly growing, often multidrug-resistant (MDR), nontuberculous mycobacteria responsible for pulmonary and other infections in susceptible hosts. Antimicrobial peptides (APs) are natural and synthetic antimicrobials active against a range of microorganisms including mycobacteria. We evaluated APs activity against MAB reference and clinical strains. We observed
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Corynebacterium rouxii sp. nov., a novel member of the diphtheriae species complex. Res. Microbiol. (IF 3.217) Pub Date : 2020-02-28 Edgar Badell,Mélanie Hennart,Carla Rodrigues,Virginie Passet,Melody Dazas,Leonardo Panunzi,Valérie Bouchez,Annick Carmi-Leroy,Julie Toubiana,Sylvain Brisse
A group of six clinical isolates previously identified as Corynebacterium diphtheriae biovar Belfanti, isolated from human cutaneous or peritoneum infections and from one dog, were characterized by genomic sequencing, biochemical analysis and MALDI-TOF mass spectrometry. The six isolates were negative for the diphtheria toxin gene. Phylogenetic analyses showed that the six isolates (including FRC0190T)
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Phenotypic comparison and DNA sequencing analysis of a wild-type and a pediocin-resistant mutant of Listeria ivanovii. Res. Microbiol. (IF 3.217) Pub Date : 2020-02-28 Shanna Liu,Yongjun Liu,Timo M Takala,Pingping Zhang,Suhua Wang
Listeria ivanovii is one of the two pathogenic species within the genus Listeria, the other being Listeria monocytogenes. In this study, we generated a stable pediocin resistant mutant Liv-r1 of a L. ivanovii strain, compared phenotypic differences between the wild-type and the mutant, localised the pediocin-induced mutations in the chromosome, and analysed the mechanisms behind the bacteriocin resistance
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Dividing subpopulation of Escherichia coli in stationary phase. Res. Microbiol. (IF 3.217) Pub Date : 2020-02-14 Arvi Jõers,Eliis Liske,Tanel Tenson
The bacterial growth cycle contains different phases: after the growth substrate is exhausted or the toxic waste products accumulate the growth stops. In this non-growing culture the number of colony forming bacteria remains constant or starts to decrease. It has been shown that during prolonged incubation there is constant growth and death of bacteria and certain mutant populations take over the culture
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Amino acids are key substrates to Escherichia coli BW25113 for achieving high specific growth rate. Res. Microbiol. (IF 3.217) Pub Date : 2020-02-11 Andres Maser,Karl Peebo,Raivo Vilu,Ranno Nahku
Studying substrate consumption in nutrient-rich conditions is challenging because often the growth medium includes undefined components like yeast extract or peptone. For clear and consistent results, it is necessary to use defined medium, where substrate utilization can be followed. In the present work, Escherichia coli BW25113 batch growth in a medium supplemented with 20 proteinogenic amino acids
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Polyamine depletion has global effects on stress and virulence gene expression and affects HilA translation in Salmonella enterica serovar typhimurium. Res. Microbiol. (IF 3.217) Pub Date : 2020-01-25 Priscila R Guerra,Gang Liu,Sebastien Lemire,Arkadiusz Nawrocki,Egle Kudirkiene,Jakob Møller-Jensen,John E Olsen,Lotte Jelsbak
Polyamines are small cationic amines required for modulating multiple cell process, including cell growth and DNA and RNA stability. In Salmonella polyamines are primarily synthesized from L-arginine or L-ornithine. Based on a previous study, which demonstrated that polyamines affect the expression of virulence gene in S. Typhimurium, we investigated the role of polyamines in the global gene and protein
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Copper limiting threshold in the terrestrial ammonia oxidizing archaeon Nitrososphaera viennensis. Res. Microbiol. (IF 3.217) Pub Date : 2020-01-25 Carolina Reyes,Logan H Hodgskiss,Oliver Baars,Melina Kerou,Barbara Bayer,Christa Schleper,Stephan M Kraemer
Ammonia oxidizing archaea (AOA) inhabiting soils have a central role in the global nitrogen cycle. Copper (Cu) is central to many enzymes in AOA including ammonia monooxygenase (AMO), the enzyme involved in the first step of ammonia oxidation. This study explored the physiological response of the AOA soil isolate, Nitrososphaera viennensis (EN76T) to Cu-limiting conditions in order to approach its
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Distribution of carbapenem resistant Acinetobacter baumannii with blaADC-30 and induction of ADC-30 in response to beta-lactam antibiotics. Res. Microbiol. (IF 3.217) Pub Date : 2020-01-25 Birson Ingti,Supriya Upadhyay,Monalisha Hazarika,Annie Bakorlin Khyriem,Deepjyoti Paul,Prithwis Bhattacharya,S R Joshi,Debajyoti Bora,Debadatta Dhar,Amitabha Bhattacharjee
A wide range of intrinsic Acinetobacter-derived cephalosporinases (ADC) along with other carbapenemases has now been detected in Acinetobacter baumannii leaving clinicians with few treatment options. The present study reports the spread of ADC-30 co-producing KPC-2 along with other β-lactamases among carbapenem resistant A. baumannii strains obtained from ICU patients in two Indian hospitals. Primer
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Escherichia coli O-antigen capsule (group 4) is essential for serum resistance. Res. Microbiol. (IF 3.217) Pub Date : 2020-01-24 Dvora Biran,Ilan Rosenshine,Eliora Z Ron
Many septicemic Escherichia coli strains produce polysaccharide capsules, which are important for survival in serum. Here we show that a septicemic E. coli strain of serotype O78 produce an O-antigen capsule (group 4 capsule) and we show that this capsule is essential for serum survival.
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Biodiversity and richness shifts of mucosa-associated gut microbiota with progression of colorectal cancer. Res. Microbiol. (IF 3.217) Pub Date : 2020-01-24 Hong-Wei Pan,Lu-Tao Du,Wei Li,Yong-Mei Yang,Yi Zhang,Chuan-Xin Wang
The host-associated gut microbiota is considered critical for the occurrence and progression of colorectal cancer (CRC); however, systematic evaluations of the changes in the biodiversity and richness of mucosa-associated gut microbiota with the development of CRC have been limited. Twenty-three paired samples from colorectal tumor sites and the surrounding non-tumor tissues were collected from stage
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Antioxidative system of Deinococcus radiodurans. Res. Microbiol. (IF 3.217) Pub Date : 2019-11-19 Hui-Zhou Qi,Wu-Zhou Wang,Jun-Yan He,Yun Ma,Fang-Zhu Xiao,Shu-Ya He
Deinococcus radiodurans is famous for its extreme resistance to various stresses such as ionizing radiation (IR), desiccation and oxidative stress. The underlying mechanism of exceptional resistance of this robust bacterium still remained unclear. However, the antioxidative system of D. radiodurans has been considered to be the determinant factor for its unparalleled resistance and protects the proteome
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Between computational predictions and high-throughput transcriptional profiling: in depth expression analysis of the OppB trans-membrane subunit of Escherichia coli OppABCDF oligopeptide transporter. Res. Microbiol. (IF 3.217) Pub Date : 2019-11-05 Irina S Masulis,Natalia A Sukharycheva,Sergey S Kiselev,Zaira Sh Andreeva,Olga N Ozoline
Bacterial oligopeptide transporters encoded by arrays of opp genes are implicated in a wide variety of physiological functions including nutrient acquisition, cell-to-cell communication, host-pathogen interaction. Combining the five opp genes in one oppABCDF operon of Escherichia coli assumes unified principle of their transcriptional regulation, which should provide a comparable amounts of translated
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Original sequence divergence among Pseudomonas putida CadRs drive specificity. Res. Microbiol. (IF 3.217) Pub Date : 2019-11-12 Julien Cayron,Géraldine Effantin,Elsa Prudent,Agnès Rodrigue
Bacteria, especially those living in soils, are in constant contact with metals. Transition metals like Fe or Zn, are required for proper growth. Some other metals like Cd or Hg are only toxic. Several systems exist to detoxify cells when these metals are present in concentrations harmful to biological systems. The expression of these systems is under control of specialized regulatory proteins able
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Contrasting arsenic biogeochemical cycling in two Moroccan alkaline pit lakes. Res. Microbiol. (IF 3.217) Pub Date : 2019-11-01 Marina Héry,Angélique Desoeuvre,El Mehdi Benyassine,Odile Bruneel,Sophie Delpoux,Eléonore Resongles,Abdelilah Dekayir,Corinne Casiot
Pit lakes resulting from the flooding of abandoned mines represent a valuable freshwater reserve. However, water contamination by toxic elements, including arsenic, compromises their use for freshwater supply. For a better management of these reserves, our aim was to gain insight into arsenic cycling in two Moroccan alkaline pit lakes. We first showed that dimethylarsenic dominated in stratified lake
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Bacterial ABC transporters of iron containing compounds. Res. Microbiol. (IF 3.217) Pub Date : 2019-11-01 Philippe Delepelaire
Iron acquisition is an essential aspect of cell physiology for most bacteria. Although much is known about how bacteria initially recognize the various iron sources they can encounter, whether siderophore, heme, host iron/heme binding proteins, much less is known about how the iron containing compounds (Fe2+, Fe3+, Fe3+-siderophore complex or heme) are transported across the cytoplasmic membrane. This
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ABC systems: structural and functional variations on a common theme. Res. Microbiol. (IF 3.217) Pub Date : 2019-10-25 Grégory Boël,Cédric Orelle,Jean-Michel Jault,Elie Dassa
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Genome insights of mercury methylation among Desulfovibrio and Pseudodesulfovibrio strains. Res. Microbiol. (IF 3.217) Pub Date : 2019-10-23 Marisol Goñi-Urriza,Christophe Klopp,Magali Ranchou-Peyruse,Anthony Ranchou-Peyruse,Mathilde Monperrus,Bahia Khalfaoui-Hassani,Rémy Guyoneaud
Mercury methylation converts inorganic mercury into the toxic methylmercury, and the consequences of this transformation are worrisome for human health and the environment. This process is performed by anaerobic microorganisms, such as several strains related to Pseudodesulfovibrio and Desulfovibrio genera. In order to provide new insights into the molecular mechanisms of mercury methylation, we performed
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In situ metabolic activities of uncultivated Ferrovum sp. CARN8 evidenced by metatranscriptomic analysis. Res. Microbiol. (IF 3.217) Pub Date : 2019-10-10 Frédéric Plewniak,Sandrine Koechler,Denis Le Paslier,Marina Héry,Odile Bruneel,Philippe N Bertin
Amongst iron-oxidizing bacteria playing a key role in the natural attenuation of arsenic in acid mine drainages (AMDs), members of the Ferrovum genus were identified in mine effluent or water treatment plants, and were shown to dominate biogenic precipitates in field pilot experiments. In order to address the question of the in situ activity of the uncultivated Ferrovum sp. CARN8 strain in the Carnoulès
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Erratum to "Description of Klebsiella africanensis sp. nov., Klebsiella variicola subsp. tropicalensis subsp. nov. and Klebsiella variicola subsp. variicola subsp. nov." [Res Microbiol 170 (3) (2019) 165-170]. Res. Microbiol. (IF 3.217) Pub Date : 2019-10-09 Carla Rodrigues,Virginie Passet,Andriniaina Rakotondrasoa,Thierno Abdoulaye Diallo,Alexis Criscuolo,Sylvain Brisse
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ABC-F proteins in mRNA translation and antibiotic resistance. Res. Microbiol. (IF 3.217) Pub Date : 2019-09-26 Farès Ousalem,Shikha Singh,Olivier Chesneau,John F Hunt,Grégory Boël
The ATP binding cassette protein superfamily comprises ATPase enzymes which are, for the most part, involved in transmembrane transport. Within this superfamily however, some protein families have other functions unrelated to transport. One example is the ABC-F family, which comprises an extremely diverse set of cytoplasmic proteins. All of the proteins in the ABC-F family characterized to date act
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Simple or complex organic substrates inhibit arsenite oxidation and aioA gene expression in two β-Proteobacteria strains. Res. Microbiol. (IF 3.217) Pub Date : 2019-09-25 Tiffanie Lescure,Catherine Joulian,Clément Charles,Taoikal Ben Ali Saanda,Mickael Charron,Dominique Breeze,Pascale Bauda,Fabienne Battaglia-Brunet
Microbial transformation of arsenic species and their interaction with the carbon cycle play a major role in the mobility of this toxic metalloid in the environment. The influence of simple or complex organic substrates on arsenic bio-oxidation was studied using two bacterial strains: one - the arsenivorans strain of Thiomonas delicata - is able to use AsIII as sole energy source; the other, Herminiimonas
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PDR-like ABC systems in pathogenic fungi. Res. Microbiol. (IF 3.217) Pub Date : 2019-09-25 Alexis Moreno,Atanu Banerjee,Rajendra Prasad,Pierre Falson
ABC transporters of the Pleiotropic Drug Resistance (PDR) family are the main actors of antifungal resistance in pathogenic fungi. While their involvement in clinical resistant strains has been proven, their transport mechanism remains unclear. Notably, one hallmark of PDR transporters is their asymmetry, with one canonical nucleotide-binding site capable of ATP hydrolysis while the other site is not
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An integrated transport mechanism of the maltose ABC importer. Res. Microbiol. (IF 3.217) Pub Date : 2019-09-24 Rebecca Mächtel,Alessandra Narducci,Douglas A Griffith,Thorben Cordes,Cédric Orelle
ATP-binding cassette (ABC) transporters use the energy of ATP hydrolysis to transport a large diversity of molecules actively across biological membranes. A combination of biochemical, biophysical, and structural studies has established the maltose transporter MalFGK2 as one of the best characterized proteins of the ABC family. MalF and MalG are the transmembrane domains, and two MalKs form a homodimer
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FLO8 deletion leads to azole resistance by upregulating CDR1 and CDR2 in Candida albicans. Res. Microbiol. (IF 3.217) Pub Date : 2019-08-23 Wen-Jing Li,Jin-Yan Liu,Ce Shi,Yue Zhao,Ling-Ning Meng,Fang Wu,Ming-Jie Xiang
Candida albicans has the ability to switch reversibly between budding yeast, filamentous, pseudohypha, and hyphal forms, a process in which the transcription factor Flo8 plays an important role. This ability is important for the virulence and pathogenicity of C. albicans. To determine whether Flo8 plays a role in the regulation of drug sensitivity, we constructed a FLO8 null mutant flo8/flo8 from the
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Energy coupling in ABC exporters. Res. Microbiol. (IF 3.217) Pub Date : 2019-08-20 Hendrik W van Veen,Himansha Singh,Kelvin Agboh,Lisa A Fagg,Dawei Guo,Brendan Swain,Robbin F de Kruijf,Charlotte Guffick
Multidrug transporters are important and interesting molecular machines that extrude a wide variety of cytotoxic drugs from target cells. This review summarizes novel insights in the energetics and mechanisms of bacterial ATP-binding cassette multidrug transporters as well as recent advances connecting multidrug transport to ion and lipid translocation processes in other membrane proteins.
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Rise and rise of the ABC transporter families. Res. Microbiol. (IF 3.217) Pub Date : 2019-08-20 I Barry Holland
This review will inevitably be influenced by my personal experience and personal view of the progression of this amazing family of proteins. This has generated a huge literature in over nearly five decades, some ideas have bloomed and faded while others have persisted, other contributions simply become redundant, overtaken by better techniques. At the outset, the pioneers had no idea of the magnitude