keyword
MENU ▼
Read by QxMD icon Read
search

tb toxin

keyword
https://www.readbyqxmd.com/read/28298445/the-structure-and-function-of-mycobacterium-tuberculosis-mazf-mt6-provides-insights-into-conserved-features-of-mazf-endonucleases
#1
Eric D Hoffer, Stacey J Miles, Christine M Dunham
Toxin-antitoxin systems are ubiquitous in prokaryotic and archaea genomes and regulate growth in response to stress. E. coli contains at least 36 putative toxin-antitoxin gene pairs, and some pathogens such as Mycobacterium tuberculosis (Mtb) have over 90 toxin-antitoxin operons. E. coli MazF cleaves free mRNA after encountering stress and nine Mtb MazF family members cleave mRNA, tRNA, or rRNA. Moreover, Mtb MazF-mt6 cleaves 23S rRNA Helix 70 to inhibit protein synthesis. The overall tertiary folds of these MazFs are predicted to be similar, therefore it is unclear how they recognize structurally distinct RNAs...
March 15, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28258153/rationalized-design-of-a-mucosal-vaccine-protects-against-mycobacterium-tuberculosis-challenge-in-mice
#2
Mushtaq Ahmed, Hongmei Jiao, Racquel Domingo-Gonzalez, Shibali Das, Kristin L Griffiths, Javier Rangel-Moreno, Uma M Nagarajan, Shabaana A Khader
Pulmonary tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) is a leading cause of global morbidity and mortality. The only licensed TB vaccine, Mycobacterium bovis bacillus Calmette-Guerin (BCG), has variable efficacy in protecting against pulmonary TB. Thus, the development of more effective TB vaccines is critical to control the TB epidemic. Specifically, vaccines delivered through the mucosal route are known to induce Th17 responses and provide superior protection against Mtb infection. However, already tested Th17-inducing mucosal adjuvants, such as heat-labile enterotoxins and cholera toxins, are not considered safe for use in humans...
March 3, 2017: Journal of Leukocyte Biology
https://www.readbyqxmd.com/read/28137237/model-systems-for-pulmonary-infectious-diseases-paradigms-of-anthrax-and-tuberculosis
#3
Gunjan Arora, Richa Misra, Andaleeb Sajid
Robert Koch utilized animal model systems to put forward his postulates while discovering the etiological agents of anthrax and tuberculosis, Bacillus anthracis and Mycobacterium tuberculosis, respectively. After more than 130 years, we have achieved limited success towards understanding these two pestilences, which have propagated as scourge against humans. B. anthracis and M. tuberculosis are diverse organisms, which share a common evolutionary path in tropics. They adapt unique strategies to overcome unfavorable conditions and surpass the host defense mechanisms...
January 30, 2017: Current Topics in Medicinal Chemistry
https://www.readbyqxmd.com/read/28088183/incidence-aetiology-and-outcome-of-community-acquired-acute-kidney-injury-in-medical-admissions-in-malawi
#4
Rhys D R Evans, Ulla Hemmilä, Alison Craik, Mwayi Mtekateka, Fergus Hamilton, Zuze Kawale, Christopher J Kirwan, Hamish Dobbie, Gavin Dreyer
BACKGROUND: Epidemiological data on Acute Kidney Injury (AKI) from low-income countries is sparse. The aim of this study was to establish the incidence, severity, aetiology, and outcomes of community-acquired AKI in Malawi. METHODS: We conducted a prospective observational study of general medical admissions to a tertiary hospital in Blantyre between 27(th) April and 17(th) July 2015. All patients were screened on admission with a serum creatinine; those with creatinine above laboratory reference range were managed by the nephrology team...
January 14, 2017: BMC Nephrology
https://www.readbyqxmd.com/read/27939941/the-toxin-antitoxin-system-dartg-catalyzes-reversible-adp-ribosylation-of-dna
#5
Gytis Jankevicius, Antonio Ariza, Marijan Ahel, Ivan Ahel
The discovery and study of toxin-antitoxin (TA) systems helps us advance our understanding of the strategies prokaryotes employ to regulate cellular processes related to the general stress response, such as defense against phages, growth control, biofilm formation, persistence, and programmed cell death. Here we identify and characterize a TA system found in various bacteria, including the global pathogen Mycobacterium tuberculosis. The toxin of the system (DarT) is a domain of unknown function (DUF) 4433, and the antitoxin (DarG) a macrodomain protein...
December 15, 2016: Molecular Cell
https://www.readbyqxmd.com/read/27936238/trehalose-6-phosphate-mediated-toxicity-determines-essentiality-of-otsb2-in-mycobacterium-tuberculosis-in-vitro-and-in-mice
#6
Jan Korte, Marina Alber, Carolina M Trujillo, Karl Syson, Hendrik Koliwer-Brandl, René Deenen, Karl Köhrer, Michael A DeJesus, Travis Hartman, William R Jacobs, Stephen Bornemann, Thomas R Ioerger, Sabine Ehrt, Rainer Kalscheuer
Trehalose biosynthesis is considered an attractive target for the development of antimicrobials against fungal, helminthic and bacterial pathogens including Mycobacterium tuberculosis. The most common biosynthetic route involves trehalose-6-phosphate (T6P) synthase OtsA and T6P phosphatase OtsB that generate trehalose from ADP/UDP-glucose and glucose-6-phosphate. In order to assess the drug target potential of T6P phosphatase, we generated a conditional mutant of M. tuberculosis allowing the regulated gene silencing of the T6P phosphatase gene otsB2...
December 2016: PLoS Pathogens
https://www.readbyqxmd.com/read/27917833/crystal-structure-of-the-toxin-msmeg_6760-the-structural-homolog-of-mycobacterium-tuberculosis-rv2035-a-novel-type-ii-toxin-involved-in-the-hypoxic-response
#7
R Alexandra Bajaj, Mark A Arbing, Annie Shin, Duilio Cascio, Linda Miallau
The structure of Msmeg_6760, a protein of unknown function, has been determined. Biochemical and bioinformatics analyses determined that Msmeg_6760 interacts with a protein encoded in the same operon, Msmeg_6762, and predicted that the operon is a toxin-antitoxin (TA) system. Structural comparison of Msmeg_6760 with proteins of known function suggests that Msmeg_6760 binds a hydrophobic ligand in a buried cavity lined by large hydrophobic residues. Access to this cavity could be controlled by a gate-latch mechanism...
December 1, 2016: Acta Crystallographica. Section F, Structural Biology Communications
https://www.readbyqxmd.com/read/27891500/interspecies-communication-between-pathogens-and-immune-cells-via-bacterial-membrane-vesicles
#8
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
#9
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
#10
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
#11
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...
January 2017: 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
#12
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
#13
Lindsey H M Te Brake, Jeroen J M W van den Heuvel, Aaron O Buaben, Reinout van Crevel, Albert Bilos, Frans G Russel, Rob E Aarnoutse, Jan B Koenderink
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 (rifampin, isoniazid, pyrazinamide, ethambutol, amikacin, moxifloxacin, and linezolid) on metformin transport and whether TB drugs are also substrates themselves of OCTs and MATEs...
December 2016: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/27599842/vapcs-of-mycobacterium-tuberculosis-cleave-rnas-essential-for-translation
#14
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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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"