keyword
MENU ▼
Read by QxMD icon Read
search

toxin and antitoxin

keyword
https://www.readbyqxmd.com/read/29237374/maze-antitoxin-of-toxin-antitoxin-system-and-fbpa-as-reliable-targets-to-eradication-of-neisseria-meningitidis
#1
Abbas Maleki, Sobhan Ghafourian, Iraj Pakzad, Behzad Badakhsh, Nourkhoda Sadeghifard
BACKGROUND: Neisseria meningitidis is ‎considered as a dangerous pathogen ‎threaten human health. Now a day, the new drug target is focused. Toxin antitoxin (TA) system recently identified as an antimicrobial drug target. Also, in N. meningitidis iron-uptake system could be an interesting target for drug discovery. METHODS: Therefore, in this study fbpA and mazE genes were chosen as new antimicrobial targets and treated with antisense peptide nucleic ‎acid (PNA)...
December 12, 2017: Current Pharmaceutical Design
https://www.readbyqxmd.com/read/29236773/first-insights-into-a-type-ii-toxin-antitoxin-system-from-the-clinical-isolate-mycobacterium-sp-mhsd3-similar-to-epsilon-zeta-systems
#2
Daniel Jaén-Luchoro, Francisco Aliaga-Lozano, Rosa Maria Gomila, Margarita Gomila, Francisco Salvà-Serra, Jorge Lalucat, Antoni Bennasar-Figueras
A putative type II toxin-antitoxin (TA) system was found in the clinical isolate Mycobacterium sp. MHSD3, a strain closely related to Mycobacterium chelonae. Further analyses of the protein sequences of the two genes revealed the presence of domains related to a TA system. BLAST analyses indicated the presence of closely related proteins in the genomes of other recently published M. chelonae strains. The functionality of both elements of the TA system was demonstrated when expressed in Escherichia coli cells, and the predicted structure of the toxin is very similar to those of well-known zeta-toxins, leading to the definition of a type II TA system similar to epsilon/zeta TA systems in strains that are closely related to M...
2017: PloS One
https://www.readbyqxmd.com/read/29233898/prophages-and-growth-dynamics-confound-experimental-results-with-antibiotic-tolerant-persister-cells
#3
Alexander Harms, Cinzia Fino, Michael A Sørensen, Szabolcs Semsey, Kenn Gerdes
Bacterial persisters are phenotypic variants that survive antibiotic treatment in a dormant state and can be formed by multiple pathways. We recently proposed that the second messenger (p)ppGpp drives Escherichia coli persister formation through protease Lon and activation of toxin-antitoxin (TA) modules. This model found considerable support among researchers studying persisters but also generated controversy as part of recent debates in the field. In this study, we therefore used our previous work as a model to critically examine common experimental procedures to understand and overcome the inconsistencies often observed between results of different laboratories...
December 12, 2017: MBio
https://www.readbyqxmd.com/read/29225431/insights-from-the-protein-protein-interaction-network-analysis-of-mycobacterium-tuberculosis-toxin-antitoxin-systems
#4
Zoozeal Thakur, Renu Dharra, Vandana Saini, Ajit Kumar, Promod K Mehta
Protein-protein interaction (PPI) network analysis is a powerful strategy to understand M. tuberculosis (Mtb) system level physiology in the identification of hub proteins. In the present study, the PPI network of 79 Mtb toxin-antitoxin (TA) systems comprising of 167 nodes and 234 edges was investigated. The topological properties of PPI network were examined by 'Network analyzer' a cytoscape plugin app and STRING database. The key enriched biological processes and the molecular functions of Mtb TA systems were analyzed by STRING...
2017: Bioinformation
https://www.readbyqxmd.com/read/29218035/characterization-of-two-cryptic-plasmids-isolated-in-haiti-from-clinical-vibrio-cholerae-non-o1-non-o139
#5
Daniela Ceccarelli, Geneviève Garriss, Seon Y Choi, Nur A Hasan, Ramunas Stepanauskas, Mihai Pop, Anwar Huq, Rita R Colwell
We report the complete sequence of two novel plasmids, pSDH-1 and pSDH-2, isolated from clinical Vibrio cholerae non-O1/non-O139 during the early phase of the 2010 Haitian cholera epidemic. Plasmids were revealed by employing single-cell genomics and their genome content suggests self-mobilization and, for pSDH-2, a toxin-antitoxin (TA) system for plasmid stabilization was identified. The putative origin of replication of pSDH-2 was mapped suggesting it replicates following the ColE1 model of plasmid replication...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/29216246/draft-genome-sequence-of-actinotignum-schaalii-dsm-15541t-genetic-insights-into-the-lifestyle-cell-fitness-and-virulence
#6
Atteyet F Yassin, Stefan Langenberg, Marcel Huntemann, Alicia Clum, Manoj Pillay, Krishnaveni Palaniappan, Neha Varghese, Natalia Mikhailova, Supratim Mukherjee, T B K Reddy, Chris Daum, Nicole Shapiro, Natalia Ivanova, Tanja Woyke, Nikos C Kyrpides
The permanent draft genome sequence of Actinotignum schaalii DSM 15541T is presented. The annotated genome includes 2,130,987 bp, with 1777 protein-coding and 58 rRNA-coding genes. Genome sequence analysis revealed absence of genes encoding for: components of the PTS systems, enzymes of the TCA cycle, glyoxylate shunt and gluconeogensis. Genomic data revealed that A. schaalii is able to oxidize carbohydrates via glycolysis, the nonoxidative pentose phosphate and the Entner-Doudoroff pathways. Besides, the genome harbors genes encoding for enzymes involved in the conversion of pyruvate to lactate, acetate and ethanol, which are found to be the end products of carbohydrate fermentation...
2017: PloS One
https://www.readbyqxmd.com/read/29214346/comparative-genomics-reveals-the-presence-of-putative-toxin-antitoxin-system-in-wolbachia-genomes
#7
Kopal Singhal, Sujata Mohanty
Multiple toxin-antitoxin (TA) systems are housed in different locations within the bacterial genome and are known to be associated with various cellular processes and stress-related adaptation. In endosymbionts, although, the TA system has scarce occurrence but studies have highlighted its presence in enhancing host-symbiont interactions. Wolbachia, an obligate endosymbiont, has recently been proposed as a biocontrol agent which may be helpful in controlling vector-borne diseases. There are reports suggesting the role of TA system in inducing cytoplasmic incompatibility in case of Wolbachia, however, the underlying mechanism is still not known...
December 6, 2017: Molecular Genetics and Genomics: MGG
https://www.readbyqxmd.com/read/29212001/mechanism-of-kin-discriminatory-demarcation-line-formation-between-colonies-of-swarming-bacteria
#8
Pintu Patra, Christopher N Vassallo, Daniel Wall, Oleg A Igoshin
Swarming bacteria use kin discrimination to preferentially associate with their clonemates for certain cooperative behaviors. Kin discrimination can manifest as an apparent demarcation line (a region lacking cells or with much lower cell density) between antagonist strains swarming toward each other. In contrast, two identical strains merge with no demarcation. Experimental studies suggest contact-dependent killing between different strains as a mechanism of kin discrimination, but it is not clear whether this killing is sufficient to explain the observed patterns...
December 5, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/29205228/repression-of-ydas-toxin-is-mediated-by-transcriptional-repressor-racr-in-the-cryptic-rac-prophage-of-escherichia-coli-k-12
#9
Revathy Krishnamurthi, Swagatha Ghosh, Supriya Khedkar, Aswin Sai Narain Seshasayee
Horizontal gene transfer is a major driving force behind the genomic diversity seen in prokaryotes. The cryptic rac prophage in Escherichia coli K-12 carries the gene for a putative transcription factor RacR, whose deletion is lethal. We have shown that the essentiality of racR in E. coli K-12 is attributed to its role in transcriptionally repressing toxin gene(s) called ydaS and ydaT, which are adjacent to and coded divergently to racR. IMPORTANCE Transcription factors in the bacterium E. coli are rarely essential, and when they are essential, they are largely toxin-antitoxin systems...
November 2017: MSphere
https://www.readbyqxmd.com/read/29201017/characterization-of-metagenomes-in-urban-aquatic-compartments-reveals-high-prevalence-of-clinically-relevant-antibiotic-resistance-genes-in-wastewaters
#10
Charmaine Ng, Martin Tay, Boonfei Tan, Thai-Hoang Le, Laurence Haller, Hongjie Chen, Tse H Koh, Timothy M S Barkham, Karina Y-H Gin
The dissemination of antimicrobial resistance (AMR) is an escalating problem and a threat to public health. Comparative metagenomics was used to investigate the occurrence of antibiotic resistant genes (ARGs) in wastewater and urban surface water environments in Singapore. Hospital and municipal wastewater (n = 6) were found to have higher diversity and average abundance of ARGs (303 ARG subtypes, 197,816 x/Gb) compared to treated wastewater effluent (n = 2, 58 ARG subtypes, 2,692 x/Gb) and surface water (n = 5, 35 subtypes, 7,985 x/Gb)...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/29182512/global-mapping-of-mtra-binding-sites-links-mtra-to-regulation-of-its-targets-in-mycobacterium-tuberculosis
#11
Ayan Chatterjee, Arun Kumar Sharma, Amar Chandra Mahatha, Srijon Kaushik Banerjee, Manish Kumar, Sudipto Saha, Joyoti Basu, Manikuntala Kundu
Mycobacterium tuberculosis employs two-component systems (TCSs) for survival within its host. The TCS MtrAB is conserved among mycobacteria. The response regulator MtrA is essential in M. tuberculosis. The genome-wide chromatin immunoprecipitation (ChIP) sequencing performed in this study suggested that MtrA binds upstream of at least 45 genes of M. tuberculosis, including those involved in cell wall remodelling, stress responses, persistence and regulation of transcription. It binds to the promoter regions and regulates the peptidoglycan hydrolases rpfA and rpfC, which are required for resuscitation from dormancy...
November 28, 2017: Microbiology
https://www.readbyqxmd.com/read/29174678/an-in-vitro-cell-based-potency-assay-for-pharmaceutical-type-a-botulinum-antitoxins
#12
Amram Torgeman, Eran Diamant, Lilach Levin, Alon Ben David, Eyal Epstein, Meni Girshengorn, Ohad Mazor, Ronit Rosenfeld, Ran Zichel
Botulism therapy relies on passive immunization with antitoxin. The mouse neutralization test is the only pharmacopeia assay to measure the potency of antitoxin preparations. Herein, we present an in vitro cell-based assay for the measurement of pharmaceutical type A antitoxin potency. Accuracy, reproducibility and compatibility with the mouse bioassay were demonstrated using different batches of standard antitoxin and toxin preparations. The established assay may substantially reduce the use of laboratory animals in the process of pharmaceutical antitoxin production...
November 22, 2017: Vaccine
https://www.readbyqxmd.com/read/29168727/a-supercluster-of-neutralizing-epitopes-at-the-interface-of-ricin-s-enzymatic-rta-and-binding-rtb-subunits
#13
Amanda Y Poon, David J Vance, Yinghui Rong, Dylan Ehrbar, Nicholas J Mantis
As part of an effort to engineer ricin antitoxins and immunotherapies, we previously produced and characterized a collection of phage-displayed, heavy chain-only antibodies (VHHs) from alpacas that had been immunized with ricin antigens. In our initial screens, we identified nine VHHs directed against ricin toxin's binding subunit (RTB), but only one, JIZ-B7, had toxin-neutralizing activity. Linking JIZ-B7 to different VHHs against ricin's enzymatic subunit (RTA) resulted in several bispecific antibodies with potent toxin-neutralizing activity in vitro and in vivo...
November 23, 2017: Toxins
https://www.readbyqxmd.com/read/29166654/therapeutic-efficacy-of-equine-botulism-antitoxin-in-rhesus-macaques
#14
Shantha Kodihalli, Andrew Emanuel, Teresa Takla, Yi Hua, Charles Hobbs, Ross LeClaire, Denise C O'Donnell
BACKGROUND: There are currently no licensed vaccines available for prevention of botulism in humans. The vaccination is not desirable due to expanding therapeutic indications of botulinum toxins. The only available specific treatment for botulism is antitoxin to remove circulating toxin, thus, preventing further neuronal damage. BAT® (Botulism Antitoxin Heptavalent (A, B, C, D, E, F, G)-(Equine)) has been developed and its therapeutic efficacy evaluated against botulinum neurotoxin serotype A (BoNT/A) in Rhesus macaques...
2017: PloS One
https://www.readbyqxmd.com/read/29152577/pseudomonas-aeruginosa-contact-dependent-growth-inhibition-plays-dual-role-in-host-pathogen-interactions
#15
Jeffrey A Melvin, Jordan R Gaston, Shawn N Phillips, Michael J Springer, Christopher W Marshall, Robert M Q Shanks, Jennifer M Bomberger
Microorganisms exist in a diverse ecosystem and have evolved many different mechanisms for sensing and influencing the polymicrobial environment around them, utilizing both diffusible and contact-dependent signals. Contact-dependent growth inhibition (CDI) is one such communication system employed by Gram-negative bacteria. In addition to CDI mediation of growth inhibition, recent studies have demonstrated CDI-mediated control of communal behaviors such as biofilm formation. We postulated that CDI may therefore play an active role in host-pathogen interactions, allowing invading strains to establish themselves at polymicrobial mucosal interfaces through competitive interactions while simultaneously facilitating pathogenic capabilities via CDI-mediated signaling...
November 2017: MSphere
https://www.readbyqxmd.com/read/29152423/foodborne-botulism-i-only-had-nacho-cheese-a-case-report
#16
Saad A Choudhry, Muhammad Jahanzaib Anwar, Muhammad Afzal, Abdul Shah
A 32-year-old female presented to the emergency department with complaints of diplopia, followed by dyspnea, chest tightness, congestion, and dysphagia. The patient was resuscitated and initial investigations were done. Within a few hours of the admission, she started developing signs of respiratory failure and was intubated and placed on the mechanical ventilator. The patient denied any ingestion of exotic food, shellfish, raw meat, or raw fish. The patient also denied traveling to any exotic place or recent camping trips...
September 8, 2017: Curēus
https://www.readbyqxmd.com/read/29149596/rational-design-of-evolutionarily-stable-microbial-kill-switches
#17
Finn Stirling, Lisa Bitzan, Samuel O'Keefe, Elizabeth Redfield, John W K Oliver, Jeffrey Way, Pamela A Silver
The evolutionary stability of synthetic genetic circuits is key to both the understanding and application of genetic control elements. One useful but challenging situation is a switch between life and death depending on environment. Here are presented "essentializer" and "cryodeath" circuits, which act as kill switches in Escherichia coli. The essentializer element induces cell death upon the loss of a bi-stable cI/Cro memory switch. Cryodeath makes use of a cold-inducible promoter to express a toxin. We employ rational design and a toxin/antitoxin titering approach to produce and screen a small library of potential constructs, in order to select for constructs that are evolutionarily stable...
November 16, 2017: Molecular Cell
https://www.readbyqxmd.com/read/29133571/development-of-protective-immunity-in-new-zealand-white-rabbits-challenged-with-bacillus-anthracis-spores-and-treated-with-antibiotics-and-obiltoxaximab-a-monoclonal-antibody-against-protective-antigen
#18
Lisa N Henning, Sarah Carpenter, Gregory V Stark, Natalya V Serbina
Recommended management of inhalational anthrax, a high-priority bioterrorist threat, includes antibiotics and antitoxins. Obiltoxaximab, a chimeric monoclonal antibody against anthrax Protective Antigen (PA) is licensed under the U.S. Food and Drug Administration's (FDA's) Animal Rule for treatment of inhalational anthrax. Because of spore latency, disease re-emergence after treatment cessation is a concern and there is a need to understand development of endogenous protective immune responses following antitoxin-containing anthrax treatment regimens...
November 13, 2017: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/29114057/directed-evolution-of-secb-chaperones-toward-toxin-antitoxin-systems
#19
Ambre Julie Sala, Patricia Bordes, Sara Ayala, Nawel Slama, Samuel Tranier, Michèle Coddeville, Anne-Marie Cirinesi, Marie-Pierre Castanié-Cornet, Lionel Mourey, Pierre Genevaux
SecB chaperones assist protein export in bacteria. However, certain SecB family members have diverged to become specialized toward the control of toxin-antitoxin (TA) systems known to promote bacterial adaptation to stress and persistence. In such tripartite TA-chaperone (TAC) systems, the chaperone was shown to assist folding and to prevent degradation of its cognate antitoxin, thus facilitating inhibition of the toxin. Here, we used both the export chaperone SecB of Escherichia coli and the tripartite TAC system of Mycobacterium tuberculosis as a model to investigate how generic chaperones can specialize toward the control of TA systems...
November 7, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/29109187/homologous-vapc-toxins-inhibit-translation-and-cell-growth-by-sequence-specific-cleavage-of-trna-fmet
#20
Lauren R Walling, J Scott Butler
Type II toxin-antitoxin (TA) systems play a critical role in the establishment and maintenance of bacterial dormancy. They are composed of a protein toxin and its cognate protein antitoxin. They function to regulate growth during conditions of stress, such as starvation or antibiotic treatment. As cellular proteases degrade the antitoxin, which normally binds and neutralizes the toxin, this frees the toxin to act on its cellular targets and arrest bacterial growth. TA systems are of particular concern in pathogenic organisms such as nontypeable Haemophilus influenzae (NTHi), as dormancy may lead to chronic infections and failure of antibiotic treatment...
November 6, 2017: Journal of Bacteriology
keyword
keyword
12487
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"