Read by QxMD icon Read


Michał Rurek, Magdalena Czołpińska, Tomasz Andrzej Pawłowski, Włodzimierz Krzesiński, Tomasz Spiżewski
Complex proteomic and physiological approaches for studying cold and heat stress responses in plant mitochondria are still limited. Variations in the mitochondrial proteome of cauliflower ( Brassica oleracea var. botrytis ) curds after cold and heat and after stress recovery were assayed by two-dimensional polyacrylamide gel electrophoresis (2D PAGE) in relation to mRNA abundance and respiratory parameters. Quantitative analysis of the mitochondrial proteome revealed numerous stress-affected protein spots. In cold, major downregulations in the level of photorespiratory enzymes, porine isoforms, oxidative phosphorylation (OXPHOS) and some low-abundant proteins were observed...
March 16, 2018: International Journal of Molecular Sciences
Dehbia Benkerrou, Matteo Ceccarelli
One of the greatest health threats facing modern medicine is the emergence of new bacterial strains which are increasingly resistant to almost all currently available antibiotics. According to a CDC (Center for Disease Control and Prevention) report published in 2013, 63% of Acinetobacter species have been identified as Multidrug resistant strains. As for other Gram-negative bacteria, the presence of an outer membrane increases the intrinsic resistance of A. baumannii to most antibiotics. The outer membrane of A...
March 15, 2018: Physical Chemistry Chemical Physics: PCCP
Mst Ishrat Jahan, Ryuta Tobe, Hisaaki Mihara
The extI gene in Geobacter sulfurreducens encodes a putative outer membrane channel porin, which resides within a cluster of extHIJKLMNOPQS genes. This cluster is highly conserved across the Geobacteraceae and includes multiple putative c -type cytochromes. In silico analyses of the ExtI sequence, together with Western blot analysis and proteinase protection assays, showed that it is an outer membrane protein. The expression level of ExtI did not respond to changes in osmolality and phosphate starvation. An extI -deficient mutant did not show any significant impact on fumarate or Fe(III) citrate reduction or sensitivity to β-lactam antibiotics, as compared with those of the wild-type strain...
March 11, 2018: International Journal of Molecular Sciences
Anna E Schager, C Coral Dominguez-Medina, Francesca Necchi, Francesca Micoli, Yun Shan Goh, Margaret Goodall, Adriana Flores-Langarica, Saeeda Bobat, Charlotte N L Cook, Melissa Arcuri, Arianna Marini, Lloyd D W King, Faye C Morris, Graham Anderson, Kai-Michael Toellner, Ian R Henderson, Constantino López-Macías, Calman A MacLennan, Adam F Cunningham
Antibodies acquired after vaccination or natural infection with Gram-negative bacteria, such as invasive Salmonella enterica serovar Typhimurium, can protect against disease. Immunization with naturally shed outer membrane vesicles from Gram-negative bacteria is being studied for its potential to protect against many infections, since antigens within vesicles maintain their natural conformation and orientation. Shedding can be enhanced through genetic modification, and the resulting particles, generalized modules for membrane antigens (GMMA), not only offer potential as vaccines but also can facilitate the study of B-cell responses to bacterial antigens...
March 6, 2018: MBio
Michael A Pfaller, Michael D Huband, Rodrigo E Mendes, Robert K Flamm, Mariana Castanheira
We evaluated meropenem-vaborbactam activity against 11,559 Enterobacteriaceae isolates, including 330 carbapenem-resistant phenotypes (CRE) and carbapenemase genotypes collected worldwide during 2015. Meropenem-vaborbactam (inhibitor at 8 mg/L) and comparators were susceptibility tested using reference broth microdilution methods. CRE isolates were screened for the presence of genes encoding carbapenemases and 292 (88.5%) of the CRE isolates carried these resistance genes. A total of 209 (63.3% of the CRE; 1...
March 3, 2018: International Journal of Antimicrobial Agents
Alejandra Vera-Leiva, Carla Barría-Loaiza, Sergio Carrasco-Anabalón, Celia Lima, Alejandro Aguayo-Reyes, Mariana Domínguez, Helia Bello-Toledo, Gerardo González-Rocha
The dissemination of carbapenemase-producing Enterobacteriaceae is currently considered a serious clinical problem due to the failure in the treatment of infections produced by them. Among the carbapenemases, the enzyme KPC has spread worldwide and has been identified in the main enterobacterial species related with healthcareassociated infections, although Klebsiella pneumoniae is the predominant specie. The blaKPC gene is transported, mainly by the transposon Tn4401, detected in various enterobacterial species of different sequence types (ST) and geographical origin...
October 2017: Revista Chilena de Infectología: órgano Oficial de la Sociedad Chilena de Infectología
Mariam El-Khatib, Chady Nasrallah, Julie Lopes, Que-Tien Tran, Guillaume Tetreau, Hind Basbous, Daphna Fenel, Benoit Gallet, Mathilde Lethier, Jean-Michel Bolla, Jean-Marie Pagès, Michel Vivaudou, Martin Weik, Mathias Winterhalter, Jacques-Philippe Colletier
The gram-negative pathogen Providencia stuartii forms floating communities within which adjacent cells are in apparent contact, before depositing as canonical surface-attached biofilms. Because porins are the most abundant proteins in the outer membrane of gram-negative bacteria, we hypothesized that they could be involved in cell-to-cell contact and undertook a structure-function relationship study on the two porins of P. stuartii , Omp-Pst1 and Omp-Pst2. Our crystal structures reveal that these porins can self-associate through their extracellular loops, forming dimers of trimers (DOTs) that could enable cell-to-cell contact within floating communities...
February 23, 2018: Proceedings of the National Academy of Sciences of the United States of America
Mark G Wise, Elizabeth Horvath, Katherine Young, Daniel F Sahm, Krystyna M Kazmierczak
PURPOSE: To understand the diversity of porin disruption in Klebsiella pneumoniae, the major outer membrane protein (OMP) porins, OmpK35 and OmpK36, were examined in a set of isolates that did not harbour traditional carbapenem-hydrolysing enzymes, but nevertheless tested non-susceptible to ertapenem. METHODS: A world-wide collection of Klebsiella pneumoniae isolates that were part of the Study for Monitoring Antimicrobial Resistance Trends (SMART) surveillance project over the years 2008-2014 were characterised with regard to their β-lactamase gene carriage and potential permeability defects...
March 2018: Journal of Medical Microbiology
Sushovan Dam, Jean-Marie Pagès, Muriel Masi
Bacteria have evolved several strategies to survive a myriad of harmful conditions in the environment and in hosts. In Gram-negative bacteria, responses to nutrient limitation, oxidative or nitrosative stress, envelope stress, exposure to antimicrobials and other growth-limiting stresses have been linked to the development of antimicrobial resistance. This results from the activation of protective changes to cell physiology (decreased outer membrane permeability), resistance transporters (drug efflux pumps), resistant lifestyles (biofilms, persistence) and/or resistance mutations (target mutations, production of antibiotic modification/degradation enzymes)...
January 25, 2018: Microbiology
Ali Mobasheri, Csaba Matta, Ilona Uzielienè, Emma Budd, Pablo Martín-Vasallo, Eiva Bernotiene
Chondrocytes are the main cells in the extracellular matrix of articular cartilage and possess a highly differentiated phenotype that is the hallmark of the unique physiological functions of this specialised load-bearing connective tissue. The plasma membrane of articular chondrocytes contains a rich and diverse complement of membrane proteins, known as the membranome, which defines the cell surface phenotype of the cells. The membranome is a key target of pharmacological agents and is important for chondrocyte function...
February 13, 2018: Joint, Bone, Spine: Revue du Rhumatisme
Sarah Christina Jane Jorgensen, Michael Joseph Rybak
Vaborbactam (VAB; formerly RPX7009) is a novel beta-lactamase inhibitor based on a cyclic boronic acid pharmacophore with potent inhibitory activity against Ambler class A and C beta-lactamases. It has been co-formulated with meropenem to restore its activity against Klebsiella pneumoniae carbapenemases (KPC). VAB does not inhibit class B or D carbapenemases, nor does it improve the activity of meropenem against multidrug-resistant non-fermenting Gram-negative bacilli, notably Acinetobacter spp. and Pseudomonas aeruginosa...
February 10, 2018: Pharmacotherapy
Abolfazl Jahangiri, Iraj Rasooli, Parviz Owlia, Abbas Ali Imani Fooladi, Jafar Salimian
Omp33-36 in A. baumannii, a bacterium causing serious nosocomial infections, is a virulence factor associated with the pathogen metabolic fitness as well as its adherence and invasion to human epithelial cells. This protein is also involved in interaction of the bacteria with host cells by binding to fibronectin. Moreover, Omp33-36 renders cytotoxicity to A. baumannii in addition to inducing apoptosis and modulation of autophagy. In the present study, an integrated strategy is launched to pierce into the 3D structure of Omp33-36 protein...
January 12, 2018: Computational Biology and Chemistry
Nandagopal Murugan, Jambulingam Malathi, K Lily Therese, Hajib NarahariRao Madhavan
Pseudomonas aeruginosa (P. aeruginosa) is a menacing opportunistic, nosocomial pathogen; become a growing concern as conventional antimicrobial therapy is now futile against it. Multi-drug resistant P. aeruginosa (MDRPA) has distinctive resistance mechanisms such as production of β-lactamases, repression of porin genes and over-expression of efflux pumps. The focus of this study is to standardize and application of multiplex PCR (mPCR) to detect the presence of betalactamase genes encoding blaTem, blaOXA, blaCTX-M-15, blaVim, blaGes, blaVeb, blaDIM, AmpC and Efflux pump genes encoding Mex A,B-oprM, Mex C,D-oprJ, Mex X,Y-oprN, oprD, nfxB, MexR...
February 2018: Kaohsiung Journal of Medical Sciences
Carlo Guardiani, Andrea Magrì, Andonis Karachitos, Maria Carmela Di Rosa, Simona Reina, Igor Bodrenko, Angela Messina, Hanna Kmita, Matteo Ceccarelli, Vito De Pinto
The yeast Saccharomyces cerevisiae genome is endowed with two distinct isoforms of Voltage-Dependent Anion Channel (VDAC). The isoform yVDAC2 is currently understudied with respect to the best known yVDAC1. Yet, since the discovery, the function of yVDAC2 was unclear, leading to the hypothesis that it might be devoid of a channel function. In this work we have elucidated, by bioinformatics modeling and electrophysiological analysis, the functional activity of yVDAC2. The conformation of yVDAC2 and, for comparison, of yVDAC1 were modeled using a multiple template approach involving mouse, human and zebrafish structures and both showed to arrange the sequences as the typical 19-stranded VDAC β-barrel...
February 1, 2018: Biochimica et Biophysica Acta
M Desroches, G Royer, D Roche, M Mercier-Darty, D Vallenet, C Médigue, K Bastard, C Rodriguez, O Clermont, E Denamur, J-W Decousser
More than a century ago, Theodor Escherich isolated the bacterium that was to become Escherichia coli, one of the most studied organisms. Not long after, the strain began an odyssey and landed in many laboratories across the world. As laboratory culture conditions could be responsible for major changes in bacterial strains, we conducted a genome analysis of isolates of this emblematic strain from different culture collections (England, France, the United States, Germany). Strikingly, many discrepancies between the isolates were observed, as revealed by multilocus sequence typing (MLST), the presence of virulence-associated genes, core genome MLST, and single nucleotide polymorphism/indel analyses...
January 2018: MSphere
Yafei Ye, Lijuan Xu, Yanping Han, Zhe Chen, Cailin Liu, Liang Ming
Carbapenemase-producing 'super bacteria', particularly NDM-1 and its variants, have become a major public health concern worldwide. The present study aimed to explore the molecular mechanism for carbapenem resistance of clinical Enterobacteriaceae isolates. Seventy-eight non-repeated Enterobacteriaceae strains resistant to any carbapenem were screened at the First Affiliated Hospital of Zhengzhou University (Zhengzhou, China) between December 2011 and December 2015. Outer membrane porin (OMP) proteins were detected using SDS-PAGE...
January 2018: Experimental and Therapeutic Medicine
Zaineb Hamzaoui, Alain Ocampo-Sosa, Elaa Maamar, Marta Fernandez Martinez, Sana Ferjani, Samia Hammami, Sarra Harbaoui, Nathalie Genel, Guillaume Arlet, Mabrouka Saidani, Amine Slim, Ilhem Boutiba-Ben Boubaker, Luis Martinez-Martinez
OBJECTIVES: To describe clinical and molecular characteristics of an outbreak due to metallo-β-lactamases (MBLs) producing Klebsiella pneumoniae collected at Charles Nicolle Hospital of Tunis and to analyze the impact of outer membrane porin (OMP) loss on carbapenem resistance levels. METHODS: Between 2010 and 2015, 178 carbapenem-resistant Enterobacteriaceae were isolated. Screening for MBL production was performed using combined disk diffusion method, with imipenem and ethylene diamine tetraacetic acid (EDTA) as inhibitors...
January 26, 2018: Microbial Drug Resistance: MDR: Mechanisms, Epidemiology, and Disease
Aldo Moreno-Ulloa, Adriana Miranda-Cervantes, Alexei Licea-Navarro, Christina Mansour, Ernesto Beltrán-Partida, Luis Donis-Maturano, Hilda Carolina Delgado De la Herrán, Francisco Villarreal, Carolina Álvarez-Delgado
We have reported on the capacity of (-)-epicatechin ((-)-EPI) to stimulate mitochondrial biogenesis (MiB) in mouse skeletal muscle (SkM). However, the mechanisms mediating the effects of (-)-EPI are not fully understood. We previously identified a role of the G-protein coupled estrogen receptor (GPER) in modulating the vascular effects of (-)-EPI. We therefore tested the hypothesis that GPER mediates (at least in part) the stimulatory effects of (-)-EPI on MiB in SkM cells. As an in vitro model, we employed mouse SkM-derived C2C12 myoblasts differentiated into myotubes...
January 16, 2018: European Journal of Pharmacology
Nan-Chang Chiu, Li-Min Huang, Arnold Willemsen, Chiranjiwi Bhusal, Ashwani Kumar Arora, Zenaida Reynoso Mojares, Daniela Toneatto
Neisseria meningitidis is associated with high mortality and morbidity in infants and children worldwide. This phase 3 study (NCT02173704) evaluated safety and immunogenicity of a 4-component serogroup B recombinant meningococcal vaccine (4CMenB) co-administered with routine vaccines in Taiwanese infants. In total, 225 healthy infants were randomized (2:1) to receive 4CMenB and routine vaccines (4CMenB+Routine) or routine vaccines only (Routine group) at 2, 4, 6 and 12 months of age. Routine vaccines were diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b, 13-valent pneumococcal, hepatitis B, measles-mumps-rubella and varicella vaccines...
January 16, 2018: Human Vaccines & Immunotherapeutics
Jigneshkumar Dahyabhai Prajapati, Carlos José Fernández Solano, Mathias Winterhalter, Ulrich Kleinekathöfer
In Gram-negative bacteria, the lack or quenching of antibiotics translocation across the outer membrane is one of the main factors for acquiring antibiotic resistance. An atomic level comprehension of the key features governing the transport of drugs by outer membrane protein channels will be very helpful in developing the next generation of antibiotics. In a previous study [J. D. Prajapati et al, J. Chem. Theory Comput. 2017, 13, 4553--4566], we characterized the diffusion pathway of the ciprofloxacin molecule through the outer membrane porin OmpC of E...
January 6, 2018: Journal of Physical Chemistry. B
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"