journal
MENU ▼
Read by QxMD icon Read
search

MBio

journal
https://www.readbyqxmd.com/read/28720735/a-nonredundant-phosphopantetheinyl-transferase-ppta-is-a-novel-antifungal-target-that-directs-secondary-metabolite-siderophore-and-lysine-biosynthesis-in-aspergillus-fumigatus-and-is-critical-for-pathogenicity
#1
Anna Johns, Daniel H Scharf, Fabio Gsaller, Hella Schmidt, Thorsten Heinekamp, Maria Straßburger, Jason D Oliver, Mike Birch, Nicola Beckmann, Katharine S Dobb, Jane Gilsenan, Bharatkumar Rash, Elaine Bignell, Axel A Brakhage, Michael J Bromley
Secondary metabolites are key mediators of virulence for many pathogens. Aspergillus fumigatus produces a vast array of these bioactive molecules, the biosynthesis of which is catalyzed by nonribosomal peptide synthetases (NRPSs) or polyketide synthases (PKSs). Both NRPSs and PKSs harbor carrier domains that are primed for acceptance of secondary metabolic building blocks by a phosphopantetheinyl transferase (P-pant). The A. fumigatus P-pant PptA has been shown to prime the putative NRPS Pes1 in vitro and has an independent role in lysine biosynthesis; however, its role in global secondary metabolism and its impact on virulence has not been described...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720734/lack-of-acrb-efflux-function-confers-loss-of-virulence-on-salmonella-enterica-serovar-typhimurium
#2
Xuan Wang-Kan, Jessica M A Blair, Barbara Chirullo, Jonathan Betts, Roberto M La Ragione, Alasdair Ivens, Vito Ricci, Timothy J Opperman, Laura J V Piddock
AcrAB-TolC is the paradigm resistance-nodulation-division (RND) multidrug resistance efflux system in Gram-negative bacteria, with AcrB being the pump protein in this complex. We constructed a nonfunctional AcrB mutant by replacing D408, a highly conserved residue essential for proton translocation. Western blotting confirmed that the AcrB D408A mutant had the same native level of expression of AcrB as the parental strain. The mutant had no growth deficiencies in rich or minimal medium. However, compared with wild-type SL1344, the mutant had increased accumulation of Hoechst 33342 dye and decreased efflux of ethidium bromide and was multidrug hypersusceptible...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720733/dengue-virus-hijacks-a-noncanonical-oxidoreductase-function-of-a-cellular-oligosaccharyltransferase-complex
#3
David L Lin, Natalia A Cherepanova, Leonia Bozzacco, Margaret R MacDonald, Reid Gilmore, Andrew W Tai
Dengue virus (DENV) is the most common arboviral infection globally, infecting an estimated 390 million people each year. We employed a genome-wide clustered regularly interspaced short palindromic repeat (CRISPR) screen to identify host dependency factors required for DENV propagation and identified the oligosaccharyltransferase (OST) complex as an essential host factor for DENV infection. Mammalian cells express two OSTs containing either STT3A or STT3B. We found that the canonical catalytic function of the OSTs as oligosaccharyltransferases is not necessary for DENV infection, as cells expressing catalytically inactive STT3A or STT3B are able to support DENV propagation...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720732/pseudomonas-aeruginosa-alters-staphylococcus-aureus-sensitivity-to-vancomycin-in-a-biofilm-model-of-cystic-fibrosis-infection
#4
Giulia Orazi, George A O'Toole
The airways of cystic fibrosis (CF) patients have thick mucus, which fosters chronic, polymicrobial infections. Pseudomonas aeruginosa and Staphylococcus aureus are two of the most prevalent respiratory pathogens in CF patients. In this study, we tested whether P. aeruginosa influences the susceptibility of S. aureus to frontline antibiotics used to treat CF lung infections. Using our in vitro coculture model, we observed that addition of P. aeruginosa supernatants to S. aureus biofilms grown either on epithelial cells or on plastic significantly decreased the susceptibility of S...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720731/an-in-vitro-chicken-gut-model-demonstrates-transfer-of-a-multidrug-resistance-plasmid-from-salmonella-to-commensal-escherichia-coli
#5
Roderick M Card, Shaun A Cawthraw, Javier Nunez-Garcia, Richard J Ellis, Gemma Kay, Mark J Pallen, Martin J Woodward, Muna F Anjum
The chicken gastrointestinal tract is richly populated by commensal bacteria that fulfill various beneficial roles for the host, including helping to resist colonization by pathogens. It can also facilitate the conjugative transfer of multidrug resistance (MDR) plasmids between commensal and pathogenic bacteria which is a significant public and animal health concern as it may affect our ability to treat bacterial infections. We used an in vitro chemostat system to approximate the chicken cecal microbiota, simulate colonization by an MDR Salmonella pathogen, and examine the dynamics of transfer of its MDR plasmid harboring several genes, including the extended-spectrum beta-lactamase blaCTX-M1 We also evaluated the impact of cefotaxime administration on plasmid transfer and microbial diversity...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720730/drought-stress-results-in-a-compartment-specific-restructuring-of-the-rice-root-associated-microbiomes
#6
Christian Santos-Medellín, Joseph Edwards, Zachary Liechty, Bao Nguyen, Venkatesan Sundaresan
Plant roots support complex microbial communities that can influence plant growth, nutrition, and health. While extensive characterizations of the composition and spatial compartmentalization of these communities have been performed in different plant species, there is relatively little known about the impact of abiotic stresses on the root microbiota. Here, we have used rice as a model to explore the responses of root microbiomes to drought stress. Using four distinct genotypes, grown in soils from three different fields, we tracked the drought-induced changes in microbial composition in the rhizosphere (the soil immediately surrounding the root), the endosphere (the root interior), and unplanted soils...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720729/inhibition-of-inflammasome-dependent-interleukin-1%C3%AE-production-by-streptococcal-nad-glycohydrolase-evidence-for-extracellular-activity
#7
Dóra Hancz, Elsa Westerlund, Benedicte Bastiat-Sempe, Onkar Sharma, Christine Valfridsson, Lena Meyer, John F Love, Maghnus O'Seaghdha, Michael R Wessels, Jenny J Persson
Group A Streptococcus (GAS) is a common human pathogen and the etiologic agent of a large number of diseases ranging from mild, self-limiting infections to invasive life-threatening conditions. Two prominent virulence factors of this bacterium are the genetically and functionally linked pore-forming toxin streptolysin O (SLO) and its cotoxin NAD(+)-glycohydrolase (NADase). Overexpression of these toxins has been linked to increased bacterial virulence and is correlated with invasive GAS disease. NADase can be translocated into host cells by a SLO-dependent mechanism, and cytosolic NADase has been assigned multiple properties such as protection of intracellularly located GAS bacteria and induction of host cell death through energy depletion...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720728/disguised-as-a-sulfate-reducer-growth-of-the-deltaproteobacterium-desulfurivibrio-alkaliphilus-by-sulfide-oxidation-with-nitrate
#8
Casper Thorup, Andreas Schramm, Alyssa J Findlay, Kai W Finster, Lars Schreiber
This study demonstrates that the deltaproteobacterium Desulfurivibrio alkaliphilus can grow chemolithotrophically by coupling sulfide oxidation to the dissimilatory reduction of nitrate and nitrite to ammonium. Key genes of known sulfide oxidation pathways are absent from the genome of D. alkaliphilus Instead, the genome contains all of the genes necessary for sulfate reduction, including a gene for a reductive-type dissimilatory bisulfite reductase (DSR). Despite this, growth by sulfate reduction was not observed...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720727/impact-of-paracoccin-gene-silencing-on-paracoccidioides-brasiliensis-virulence
#9
Fabrício F Fernandes, Aline F Oliveira, Taise N Landgraf, Cristina Cunha, Agostinho Carvalho, Patrícia E Vendruscolo, Relber A Gonçales, Fausto Almeida, Thiago A da Silva, Fernando Rodrigues, Maria Cristina Roque-Barreira
Among the endemic deep mycoses in Latin America, paracoccidioidomycosis (PCM), caused by thermodimorphic fungi of the Paracoccidioides genus, is a major cause of morbidity. Disease development and its manifestations are associated with both host and fungal factors. Concerning the latter, several recent studies have employed the methodology of gene modulation in P. brasiliensis using antisense RNA (AsRNA) and Agrobacterium tumefaciens-mediated transformation (ATMT) to identify proteins that influence fungus virulence...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28720726/mitochondrial-cochaperone-mge1-is-involved-in-regulating-susceptibility-to-fluconazole-in-saccharomyces-cerevisiae-and-candida-species
#10
Liesbeth Demuyser, Erwin Swinnen, Alessandro Fiori, Beatriz Herrera-Malaver, Kevin Vestrepen, Patrick Van Dijck
MGE1 encodes a yeast chaperone involved in Fe-S cluster metabolism and protein import into the mitochondria. In this study, we identified MGE1 as a multicopy suppressor of susceptibility to the antifungal fluconazole in the model yeast Saccharomyces cerevisiae We demonstrate that this phenomenon is not exclusively dependent on the integrity of the mitochondrial DNA or on the presence of the drug efflux pump Pdr5. Instead, we show that the increased dosage of Mge1 plays a protective role by retaining increased amounts of ergosterol upon fluconazole treatment...
July 18, 2017: MBio
https://www.readbyqxmd.com/read/28698279/zika-virus-persistently-infects-and-is-basolaterally-released-from-primary-human-brain-microvascular-endothelial-cells
#11
Megan C Mladinich, John Schwedes, Erich R Mackow
Zika virus (ZIKV) is a mosquito-borne Flavivirus that has emerged as the cause of encephalitis and fetal microencephaly in the Americas. ZIKV uniquely persists in human bodily fluids for up to 6 months, is sexually transmitted, and traverses the placenta and the blood-brain barrier (BBB) to damage neurons. Cells that support persistent ZIKV replication and mechanisms by which ZIKV establishes persistence remain enigmatic but central to ZIKV entry into protected neuronal compartments. The endothelial cell (EC) lining of capillaries normally constrains transplacental transmission and forms the BBB, which selectively restricts access of blood constituents to neurons...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28698278/on-the-origin-of-reverse-transcriptase-using-crispr-cas-systems-and-their-hyperdiverse-enigmatic-spacer-repertoires
#12
Sukrit Silas, Kira S Makarova, Sergey Shmakov, David Páez-Espino, Georg Mohr, Yi Liu, Michelle Davison, Simon Roux, Siddharth R Krishnamurthy, Becky Xu Hua Fu, Loren L Hansen, David Wang, Matthew B Sullivan, Andrew Millard, Martha R Clokie, Devaki Bhaya, Alan M Lambowitz, Nikos C Kyrpides, Eugene V Koonin, Andrew Z Fire
Cas1 integrase is the key enzyme of the clustered regularly interspaced short palindromic repeat (CRISPR)-Cas adaptation module that mediates acquisition of spacers derived from foreign DNA by CRISPR arrays. In diverse bacteria, the cas1 gene is fused (or adjacent) to a gene encoding a reverse transcriptase (RT) related to group II intron RTs. An RT-Cas1 fusion protein has been recently shown to enable acquisition of CRISPR spacers from RNA. Phylogenetic analysis of the CRISPR-associated RTs demonstrates monophyly of the RT-Cas1 fusion, and coevolution of the RT and Cas1 domains...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28698277/deep-sea-hydrothermal-vent-viruses-compensate-for-microbial-metabolism-in-virus-host-interactions
#13
Tianliang He, Hongyun Li, Xiaobo Zhang
Viruses are believed to be responsible for the mortality of host organisms. However, some recent investigations reveal that viruses may be essential for host survival. To date, it remains unclear whether viruses are beneficial or harmful to their hosts. To reveal the roles of viruses in the virus-host interactions, viromes and microbiomes of sediment samples from three deep-sea hydrothermal vents were explored in this study. To exclude the influence of exogenous DNAs on viromes, the virus particles were purified with nuclease (DNase I and RNase A) treatments and cesium chloride density gradient centrifugation...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28698276/a-novel-single-cell-fish-flow-assay-identifies-effector-memory-cd4-t-cells-as-a-major-niche-for-hiv-1-transcription-in-hiv-infected-patients
#14
Judith Grau-Expósito, Carla Serra-Peinado, Lucia Miguel, Jordi Navarro, Adrià Curran, Joaquin Burgos, Imma Ocaña, Esteban Ribera, Ariadna Torrella, Bibiana Planas, Rosa Badía, Josep Castellví, Vicenç Falcó, Manuel Crespo, Maria J Buzon
Cells that actively transcribe HIV-1 have been defined as the "active viral reservoir" in HIV-infected individuals. However, important technical limitations have precluded the characterization of this specific viral reservoir during both treated and untreated HIV-1 infections. Here, we used a novel single-cell RNA fluorescence in situ hybridization-flow cytometry (FISH-flow) assay that requires only 15 million unfractionated peripheral blood mononuclear cells (PBMCs) to characterize the specific cell subpopulations that transcribe HIV RNA in different subsets of CD4(+) T cells...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28698275/crispr-cas9-genome-editing-reveals-that-the-intron-is-not-essential-for-var2csa-gene-activation-or-silencing-in-plasmodium-falciparum
#15
Jessica M Bryant, Clément Regnault, Christine Scheidig-Benatar, Sebastian Baumgarten, Julien Guizetti, Artur Scherf
Plasmodium falciparum relies on monoallelic expression of 1 of 60 var virulence genes for antigenic variation and host immune evasion. Each var gene contains a conserved intron which has been implicated in previous studies in both activation and repression of transcription via several epigenetic mechanisms, including interaction with the var promoter, production of long noncoding RNAs (lncRNAs), and localization to repressive perinuclear sites. However, functional studies have relied primarily on artificial expression constructs...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28698274/noroviruses-co-opt-the-function-of-host-proteins-vapa-and-vapb-for-replication-via-a-phenylalanine-phenylalanine-acidic-tract-motif-mimic-in-nonstructural-viral-protein-ns1-2
#16
Broc T McCune, Wei Tang, Jia Lu, James B Eaglesham, Lucy Thorne, Anne E Mayer, Emily Condiff, Timothy J Nice, Ian Goodfellow, Andrzej M Krezel, Herbert W Virgin
The Norovirus genus contains important human pathogens, but the role of host pathways in norovirus replication is largely unknown. Murine noroviruses provide the opportunity to study norovirus replication in cell culture and in small animals. The human norovirus nonstructural protein NS1/2 interacts with the host protein VAMP-associated protein A (VAPA), but the significance of the NS1/2-VAPA interaction is unexplored. Here we report decreased murine norovirus replication in VAPA- and VAPB-deficient cells. We characterized the role of VAPA in detail...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28698273/viral-micrornas-repress-the-cholesterol-pathway-and-25-hydroxycholesterol-inhibits-infection
#17
Anna K P Serquiña, Diane M Kambach, Ontara Sarker, Joseph M Ziegelbauer
From various screens, we found that Kaposi's sarcoma-associated herpesvirus (KSHV) viral microRNAs (miRNAs) target several enzymes in the mevalonate/cholesterol pathway. 3-Hydroxy-3-methylglutaryl-coenzyme A (CoA) synthase 1 (HMGCS1), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR [a rate-limiting step in the mevalonate pathway]), and farnesyl-diphosphate farnesyltransferase 1 (FDFT1 [a committed step in the cholesterol branch]) are repressed by multiple KSHV miRNAs. Transfection of viral miRNA mimics in primary endothelial cells (human umbilical vein endothelial cells [HUVECs]) is sufficient to reduce intracellular cholesterol levels; however, small interfering RNAs (siRNAs) targeting only HMGCS1 did not reduce cholesterol levels...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28698272/mycobacterium-tuberculosis-phoy-proteins-promote-persister-formation-by-mediating-pst-senx3-regx3-phosphate-sensing
#18
Sarah B Namugenyi, Alisha M Aagesen, Sarah R Elliott, Anna D Tischler
The Mycobacterium tuberculosis phosphate-specific transport (Pst) system controls gene expression in response to phosphate availability by inhibiting the activation of the SenX3-RegX3 two-component system under phosphate-rich conditions, but the mechanism of communication between these systems is unknown. In Escherichia coli, inhibition of the two-component system PhoR-PhoB under phosphate-rich conditions requires both the Pst system and PhoU, a putative adaptor protein. E. coli PhoU is also involved in the formation of persisters, a subpopulation of phenotypically antibiotic-tolerant bacteria...
July 11, 2017: MBio
https://www.readbyqxmd.com/read/28679751/aim2-like-receptors-positively-and-negatively-regulate-the-interferon-response-induced-by-cytosolic-dna
#19
Yuki Nakaya, Jingtao Lilue, Spyridon Stavrou, Eileen A Moran, Susan R Ross
Cytosolic DNAs derived from retrotransposons serve as pathogen-associated molecular patterns for pattern recognition receptors (PRRs) that stimulate the induction of interferons (IFNs) and other cytokines, leading to autoimmune disease. Cyclic GMP-AMP synthase is one PRR that senses retrotransposon DNA, activating type I IFN responses through the stimulator of IFN genes (STING). Absent in melanoma 2 (AIM2)-like receptors (ALRs) have also been implicated in these pathways. Here we show that the mouse ALR IFI205 senses cytosolic retrotransposon DNA independently of cyclic GMP-AMP production...
July 5, 2017: MBio
https://www.readbyqxmd.com/read/28679750/erratum-for-kang-et-al-gut-microbiota-mediates-the-protective-effects-of-dietary-capsaicin-against-chronic-low-grade-inflammation-and-associated-obesity-induced-by-high-fat-diet
#20
Chao Kang, Bin Wang, Kanakaraju Kaliannan, Xiaolan Wang, Hedong Lang, Suocheng Hui, Li Huang, Yong Zhang, Ming Zhou, Mengting Chen, Mantian Mi
No abstract text is available yet for this article.
July 5, 2017: MBio
journal
journal
42716
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"