keyword
MENU ▼
Read by QxMD icon Read
search

tb toxin

keyword
https://www.readbyqxmd.com/read/27891500/interspecies-communication-between-pathogens-and-immune-cells-via-bacterial-membrane-vesicles
#1
Katerina S Jurkoshek, Ying Wang, Jaffre J Athman, Marian R Barton, Pamela A Wearsch
The production of extracellular vesicles is a universal mechanism for intercellular communication that is conserved across kingdoms. Prokaryotes secrete 50-250 nm membrane vesicles (MVs) in a manner that is regulated by environmental stress and is thought to promote survival. Since many types of host-derived stress are encountered during infection, this implies an important role for MV secretion in bacterial pathogenesis. Accordingly, MVs produced by gram-positive and gram-negative pathogens contain toxins, virulence factors, and other molecules that promote survival in the host...
2016: Frontiers in Cell and Developmental Biology
https://www.readbyqxmd.com/read/27827369/chaperone-addiction-of-toxin-antitoxin-systems
#2
Patricia Bordes, Ambre Julie Sala, Sara Ayala, Pauline Texier, Nawel Slama, Anne-Marie Cirinesi, Valérie Guillet, Lionel Mourey, Pierre Genevaux
Bacterial toxin-antitoxin (TA) systems, in which a labile antitoxin binds and inhibits the toxin, can promote adaptation and persistence by modulating bacterial growth in response to stress. Some atypical TA systems, known as tripartite toxin-antitoxin-chaperone (TAC) modules, include a molecular chaperone that facilitates folding and protects the antitoxin from degradation. Here we use a TAC module from Mycobacterium tuberculosis as a model to investigate the molecular mechanisms by which classical TAs can become 'chaperone-addicted'...
November 9, 2016: Nature Communications
https://www.readbyqxmd.com/read/27723728/the-type-vii-secretion-system-of-staphylococcus-aureus-secretes-a-nuclease-toxin-that-targets-competitor-bacteria
#3
Zhenping Cao, M Guillermina Casabona, Holger Kneuper, James D Chalmers, Tracy Palmer
The type VII protein secretion system (T7SS) plays a critical role in the virulence of human pathogens including Mycobacterium tuberculosis and Staphylococcus aureus. Here, we report that the S. aureus T7SS secretes a large nuclease toxin, EsaD. The toxic activity of EsaD is neutralized during its biosynthesis through complex formation with an antitoxin, EsaG, which binds to its C-terminal nuclease domain. The secretion of EsaD is dependent on a further accessory protein, EsaE, that does not interact with the nuclease domain, but instead binds to the EsaD N-terminal region...
October 10, 2016: Nature Microbiology
https://www.readbyqxmd.com/read/27696234/toxin-a-negative-toxin-b-positive-ribotype-017-clostridium-difficile-is-the-dominant-strain-type-in-patients-with-diarrhoea-attending-tuberculosis-hospitals-in-cape-town-south-africa
#4
B Kullin, J Wojno, V Abratt, S J Reid
The molecular epidemiology of C. difficile strains causing disease in South Africa is currently unknown. Previously, multidrug resistant ribotype (RT)017 strains were those most commonly isolated from patients with diarrhoea attending Groote Schuur Hospital in Cape Town, South Africa. This larger study aimed to investigate the molecular epidemiology and antibiotic susceptibility profiles of C. difficile strains in the greater Cape Town and regional areas. C. difficile strains were isolated from patients with diarrhoea attending hospitals in the Western Cape region of South Africa that tested positive using the GeneXpert CDiff diagnostic test...
September 30, 2016: European Journal of Clinical Microbiology & Infectious Diseases
https://www.readbyqxmd.com/read/27676811/assessment-of-pain-during-the-injection-of-the-botulinum-toxin-physical-medicine-and-rehabilitation-experience
#5
Samira Lahrabli, Herman Azanmasso, Fatima Lmidmani, Abdellatif El Fatimi
OBJECTIVE: Intramuscular injection of botulinum toxin can be painful for some patients. This may be due either to a broken skin, stimulation for locating, or injecting the product. The objective of this study was to see the clinical impact of pain on injection. MATERIAL/PATIENTS AND METHODS: Retrospective study of 15 patients (6 M/9 W), average age was 31 years (11-75 years). The patients had spasticity of MS in 40% and a MI spasticity in 60%. The treatment was basic Dysport...
September 2016: Annals of Physical and Rehabilitation Medicine
https://www.readbyqxmd.com/read/27645247/moxifloxacin-is-a-potent-in-vitro-inhibitor-of-oct-and-mate-mediated-transport-of-metformin-and-ethambutol
#6
Lindsey H M Te Brake, Jeroen J M W van den Heuvel, Aaron Ohene Buaben, Reinout van Crevel, Albert Bilos, Frans G Russel, Rob E Aarnoutse, Jan B Koenderink
INTRODUCTION: It is largely unknown if simultaneous administration of tuberculosis (TB) drugs and metformin leads to drug-drug interactions (DDIs). Disposition of metformin is determined by organic cation transporters (OCTs) and multidrug and toxin extrusion proteins (MATEs). Thus any DDIs would primarily be mediated via these transporters. This study aimed to assess the in vitro inhibitory effects of TB drugs (rifampicin, isoniazid, pyrazinamide, ethambutol, amikacin, moxifloxacin and linezolid) on metformin transport, and whether TB drugs are also substrates themselves of OCTs and MATEs...
September 19, 2016: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/27599842/vapcs-of-mycobacterium-tuberculosis-cleave-rnas-essential-for-translation
#7
Kristoffer Winther, Jai J Tree, David Tollervey, Kenn Gerdes
The major human pathogen Mycobacterium tuberculosis can survive in the host organism for decades without causing symptoms. A large cohort of Toxin-Antitoxin (TA) modules contribute to this persistence. Of these, 48 TA modules belong to the vapBC (virulence associated protein) gene family. VapC toxins are PIN domain endonucleases that, in enterobacteria, inhibit translation by site-specific cleavage of initiator tRNA. In contrast, VapC20 of M. tuberculosis inhibits translation by site-specific cleavage of the universally conserved Sarcin-Ricin loop (SRL) in 23S rRNA...
November 16, 2016: Nucleic Acids Research
https://www.readbyqxmd.com/read/27576202/crystal-structure-of-vapc21-from-mycobacterium-tuberculosis-at-1-31%C3%A2-%C3%A3-resolution
#8
Paulo Jardim, Isadora Cristina da Silva Santos, João Alexandre Ribeiro Gonçalves Barbosa, Sônia Maria de Freitas, Napoleão Fonseca Valadares
Persisters are individual bacterial cells that exhibit a phenotype characterized by slow growth, low metabolic rate and multidrug tolerance. The processes that drive cells into a persistence state constitute an active but incipient research field, and structural data regarding its components are scarce. The molecular targets of many therapeutic drugs are involved in cell wall synthesis and cell division, and these cellular processes are down-regulated in persister cells, consequently these cells are more likely to survive antibiotic treatment...
September 23, 2016: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/27447671/toxin-antitoxin-systems-in-clinical-pathogens
#9
REVIEW
Laura Fernández-García, Lucia Blasco, Maria Lopez, German Bou, Rodolfo García-Contreras, Thomas Wood, María Tomas
Toxin-antitoxin (TA) systems are prevalent in bacteria and archaea. Although not essential for normal cell growth, TA systems are implicated in multiple cellular functions associated with survival under stress conditions. Clinical strains of bacteria are currently causing major human health problems as a result of their multidrug resistance, persistence and strong pathogenicity. Here, we present a review of the TA systems described to date and their biological role in human pathogens belonging to the ESKAPE group (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp...
July 20, 2016: Toxins
https://www.readbyqxmd.com/read/27431227/8-hydroxyquinolines-are-boosting-agents-of-copper-related-toxicity-in-mycobacterium-tuberculosis
#10
Santosh Shah, Alex G Dalecki, Aruni P Malalasekera, Cameron L Crawford, Suzanne M Michalek, Olaf Kutsch, Jim Sun, Stefan H Bossmann, Frank Wolschendorf
Copper (Cu) ions are likely the most important immunological metal-related toxin utilized in controlling bacterial infections. Impairment of bacterial Cu resistance reduces viability within the host. Thus, pharmacological enhancement of Cu-mediated antibacterial toxicity may lead to novel strategies in drug discovery and development. Screening for Cu toxicity-enhancing antibacterial molecules identified 8-hydroxyquinoline (8HQ) to be a potent Cu-dependent bactericidal inhibitor of Mycobacterium tuberculosis The MIC of 8HQ in the presence of Cu was 0...
October 2016: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/27379032/the-chromosomal-parde2-toxin-antitoxin-system-of-mycobacterium-tuberculosis-h37rv-genetic-and-functional-characterization
#11
Manish Gupta, Nishtha Nayyar, Meenakshi Chawla, Ramakrishnan Sitaraman, Rakesh Bhatnagar, Nirupama Banerjee
Mycobacterium tuberculosis H37Rv escapes host-generated stresses by entering a dormant persistent state. Activation of toxin-antitoxin modules is one of the mechanisms known to trigger such a state with low metabolic activity. M. tuberculosis harbors a large number of TA systems mostly located within discernible genomic islands. We have investigated the parDE2 operon of M. tuberculosis H37Rv encoding MParE2 toxin and MParD2 antitoxin proteins. The parDE2 locus was transcriptionally active from growth phase till late stationary phase in M...
2016: Frontiers in Microbiology
https://www.readbyqxmd.com/read/27303903/the-vapbc1-toxin-antitoxin-complex-from-mycobacterium-tuberculosis-purification-crystallization-and-x-ray-diffraction-analysis
#12
Zuokun Lu, Han Wang, Aili Zhang, Yusheng Tan
Mycobacterium tuberculosis, a major human pathogen, encodes at least 88 toxin-antitoxin (TA) systems. Remarkably, more than half of these modules belong to the VapBC family. Under normal growth conditions, the toxicity of the toxin VapC is neutralized by the protein antitoxin VapB. When bacteria face an unfavourable environment, the antitoxin is degraded and the free toxin VapC targets important cellular processes in order to inhibit cell growth. TA systems function in many biological processes, such as in the stringent response, in biofilm formation and in drug tolerance...
June 2016: Acta Crystallographica. Section F, Structural Biology Communications
https://www.readbyqxmd.com/read/27303898/the-secb-like-chaperone-rv1957-from-mycobacterium-tuberculosis-crystallization-and-x-ray-crystallographic-analysis
#13
Zuokun Lu, Han Wang, TingTing Yu
Protein export is important in all bacteria, and bacteria have evolved specialized export machineries to fulfil this task. In Mycobacterium tuberculosis, the causative agent of tuberculosis, the general secretion pathway (Sec pathway) is conserved and is essential in performing the export of proteins. The bacterial Sec pathway post-translationally exports unfolded proteins out of the cytoplasm, and the core of the Sec pathway is composed of a heterotrimeric membrane-embedded channel, SecYEG, and two cytosolic components, SecA and SecB...
June 2016: Acta Crystallographica. Section F, Structural Biology Communications
https://www.readbyqxmd.com/read/27176494/high-persister-mutants-in-mycobacterium-tuberculosis
#14
Heather L Torrey, Iris Keren, Laura E Via, Jong Seok Lee, Kim Lewis
Mycobacterium tuberculosis forms drug-tolerant persister cells that are the probable cause of its recalcitrance to antibiotic therapy. While genetically identical to the rest of the population, persisters are dormant, which protects them from killing by bactericidal antibiotics. The mechanism of persister formation in M. tuberculosis is not well understood. In this study, we selected for high persister (hip) mutants and characterized them by whole genome sequencing and transcriptome analysis. In parallel, we identified and characterized clinical isolates that naturally produce high levels of persisters...
2016: PloS One
https://www.readbyqxmd.com/read/27156618/longitudinal-whole-genome-analysis-of-pre-and-post-drug-treatment-mycobacterium-tuberculosis-isolates-reveals-progressive-steps-to-drug-resistance
#15
Gargi Datta, Luisa M Nieto, Rebecca M Davidson, Carolina Mehaffy, Caroline Pederson, Karen M Dobos, Michael Strong
Tuberculosis (TB) is one of the leading causes of death due to an infectious disease in the world. Understanding the mechanisms of drug resistance has become pivotal in the detection and treatment of newly emerging resistant TB cases. We have analyzed three pairs of Mycobacterium tuberculosis strains pre- and post-drug treatment to identify mutations involved in the progression of resistance to the drugs rifampicin and isoniazid. In the rifampicin resistant strain, we confirmed a mutation in rpoB (S450L) that is known to confer resistance to rifampicin...
May 2016: Tuberculosis
https://www.readbyqxmd.com/read/27005544/-polymorphisms-of-toxin-antitoxin-chaperone-system-of-mycobacterium-tuberculosis-complex-in-china
#16
Tongyang Xiao, Lili Zhao, Haican Liu, Machao Li, Xiuqin Zhao, Kanglin Wan
OBJECTIVE: To investigate the single nucleotide polymorphism (SNP) of toxin-antitoxin-chaperone (TAC) system of Mycobacterium (M.) tuberculosis with different genotypes and its biological significance. METHODS: A total of 183 clinical M. tuberculosis isolates were collected for spoligotyping. The sequences of higA,higB and Rv1957 were obtained by using PCR and DNA sequencing. The sequences were compared for possible mutations. Functional consequences of nonsynonymous SNPs were predicted by using I-Mutant 2...
March 2016: Zhonghua Liu Xing Bing Xue za Zhi, Zhonghua Liuxingbingxue Zazhi
https://www.readbyqxmd.com/read/26979042/-anti-tuberculosis-therapy-and-paradoxical-response-when-tuberculosis-develops-under-the-influence-of-biologics-for-rheumatoid-arthritis
#17
Tomoshige Matsumoto
A paradoxical response is designated as the clinical or radiological worsening of pre-existing TB lesions or the development of new lesions during appropriate anti-TB treatment. Tuberculosis bacilli have no toxin and the organism apparently does not produce any toxins, so the virulence depends on a response to the host immune reaction. According to our report, the annual reported numbers of tuberculosis cases and death did not decrease during biologics treatment in Japan. We have been monitoring and analyzing all the TB cases activated during adalimumab treatments in Japan...
November 2015: Kekkaku: [Tuberculosis]
https://www.readbyqxmd.com/read/26943324/a-blast-without-power-cell-death-induced-by-the-tuberculosis-necrotizing-toxin-fails-to-elicit-adequate-immune-responses
#18
C Maueröder, R A Chaurio, T Dumych, M Podolska, M D Lootsik, S Culemann, R P Friedrich, R Bilyy, C Alexiou, G Schett, C Berens, M Herrmann, L E Munoz
In this study, we deploy a doxycycline-dependent suicide switch integrated in a tumor challenge model. With this experimental setup, we characterized the immunological consequences of cells dying by four distinct cell death stimuli in vivo. We observed that apoptotic cell death induced by expression of the truncated form of BH3 interacting-domain death agonist (tBid) and a constitutively active form of caspase 3 (revC3), respectively, showed higher immunogenicity than cell death induced by expression of the tuberculosis-necrotizing toxin (TNT)...
June 2016: Cell Death and Differentiation
https://www.readbyqxmd.com/read/26916387/understanding-hiv-mycobacteria-synergism-through-comparative-proteomics-of-intra-phagosomal-mycobacteria-during-mono-and-hiv-co-infection
#19
Rakesh Ganji, Snigdha Dhali, Arshad Rizvi, Srikanth Rapole, Sharmistha Banerjee
Mycobacterium tuberculosis (Mtb) is the most common co-infection in HIV patients and a serious co-epidemic. Apart from increasing the risk of reactivation of latent tuberculosis (TB), HIV infection also permits opportunistic infection of environmental non-pathogenic mycobacteria. To gain insights into mycobacterial survival inside host macrophages and identify mycobacterial proteins or processes that influence HIV propagation during co-infection, we employed proteomics approach to identify differentially expressed intracellular mycobacterial proteins during mono- and HIV co-infection of human THP-1 derived macrophage cell lines...
2016: Scientific Reports
https://www.readbyqxmd.com/read/26911613/early-ifn-%C3%AE-production-together-with-decreased-expression-of-tlr3-and-tlr9-characterizes-eae-development-conditional-on-the-presence-of-myelin
#20
Marcilene Gomes Evangelista, Sandra Bertelli Ribeiro De Castro, Caio César De Souza Alves, Alyria Teixeira Dias, Viano Wyallison De Souza, Lívia Bittencourt Dos Reis, Luan Cristian Da Silva, Maria Christina Marques Nogueira Castañon, Rogério Estevam Farias, Maria Aparecida Juliano, Ana Paula Ferreira
Experimental autoimmune encephalomyelitis (EAE) is a model for the study of multiple sclerosis, which is an inflammatory and demyelinating disease of the central nervous system (CNS). Despite increased efforts to elucidate the function of toll-like receptors (TLRs) in autoimmune diseases of the CNS, the relative contribution of other factors, including the immunomodulatory properties of TLR signaling, role of the innate response and the presence or absence of myelin peptides remain unclear. The aim was to evaluate TLR expression in the CNS during EAE development by investigating the expression of TLRs in the initial phase of EAE and establishing correlations with the modulation of inflammatory factors...
June 2016: Autoimmunity
keyword
keyword
114433
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"