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pervasive domestication of defective prophages by bacteria.integrated phages (prophages) are major contributors to the diversity of bacterial gene repertoires. domestication of their components is thought to have endowed bacteria with molecular systems involved in secretion, defense, warfare, and gene transfer. however, the rates and mechanisms of domestication remain unknown. we used comparative genomics to study the evolution of prophages within the bacterial genome. we identified over 300 vertically inherited prophages within enterobacterial genomes. ...201425092302
structural and functional features of crl proteins and identification of conserved surface residues required for interaction with the rpos/σs subunit of rna polymerase.in many γ-proteobacteria, the rpos/σs sigma factor associates with the core rnap (rna polymerase) to modify global gene transcription in stationary phase and under stress conditions. the small regulatory protein crl stimulates the association of σs with the core rnap in escherichia coli and salmonella enterica serovar typhimurium, through direct and specific interaction with σs. the structural determinants of crl involved in σs binding are unknown. in the present paper we report the x-ray crysta ...201425056110
effectiveness of calcium hypochlorite on viral and bacterial contamination of alfalfa seeds.alfalfa sprouts have been involved in numerous foodborne outbreaks, which has increased the awareness for seed and sprout safety. this study compared the effectiveness of calcium hypochlorite (ca(ocl)2) on the inactivation of bacteria and viruses on alfalfa seeds and in the presence of a simulated organic load. alfalfa seeds were inoculated with human norovirus (hunov) genogroup ii (gii), murine norovirus (mnv), tulane virus (tv), escherichia coli o104:h4, and salmonella enterica serovar agona. ...201425055022
comparison of single and blend acidifiers as alternative to antibiotics on growth performance, fecal microflora, and humoral immunity in weaned piglets.the banning of the use of antibiotics as feed additive has accelerated investigations of alternative feed additives in animal production. this experiment investigated the effect of pure citric acid or acidifier blend supplementation as substitute for antibiotic growth promoters on growth performance, fecal microbial count, and humoral immunity in weaned piglets challenged with salmonella enterica serover typhimurium and escherichia coli kctc 2571. a total of 60 newly weaned piglets (crossbred, 2 ...201425049931
predicting bacterial essential genes using only sequence composition information.essential genes are those genes that are needed by organisms at any time and under any conditions. it is very important for us to identify essential genes from bacterial genomes because of their vital role in synthetic biology and biomedical practices. in this paper, we developed a support vector machine (svm)-based method to predict essential genes of bacterial genomes using only compositional features. these features are all derived from the primary sequences, i.e., nucleotide sequences and pr ...201425036505
engineering escherichia coli for odd straight medium chain free fatty acid production.microbial biosynthesis of free fatty acids (ffas) can be achieved by introducing an acyl-acyl carrier protein thioesterase gene into escherichia coli. the engineered e. coli usually produced even chain ffas. in this study, propionyl-coa synthetase (prpe) from salmonella enterica was overexpressed in two efficient even chain ffas producers, ml103 (pxzm12) carrying the acyl-acp thioesterase gene from umbellularia californica and ml103 (pxz18) carrying the acyl-acp thioesterase gene from ricinus co ...201425030454
structure of the rna polymerase assembly factor crl and identification of its interaction surface with sigma s.bacteria utilize multiple sigma factors that associate with core rna polymerase (rnap) to control transcription in response to changes in environmental conditions. in escherichia coli and salmonella enterica, crl positively regulates the σ(s) regulon by binding to σ(s) to promote its association with core rnap. we recently characterized the determinants in σ(s) responsible for specific binding to crl. however, little is known about the determinants in crl required for this interaction. here, we ...201425002538
high prevalence of blactx-m-1/inci1/st3 and blacmy-2/inci1/st2 plasmids in healthy urban dogs in france.in the community, close contacts between humans and dogs may promote the transfer of extended-spectrum beta-lactamase/plasmidic ampc cephalosporinase (esbl/pampc) genes. large-scale prevalence studies on esbl/pampc carriage in dogs are rare, and data on esbl/pampc plasmids are even more limited. here, a considerable rate of 18.5% esbl/pampc carriers was found among 368 unrelated healthy dogs in paris, france. this prevalence is much higher than the one found in healthy humans in the same city (6 ...201424982072
structure and function of the bi-directional bacterial flagellar motor.the bacterial flagellum is a locomotive organelle that propels the bacterial cell body in liquid environments. the flagellum is a supramolecular complex composed of about 30 different proteins and consists of at least three parts: a rotary motor, a universal joint, and a helical filament. the flagellar motor of escherichia coli and salmonella enterica is powered by an inward-directed electrochemical potential difference of protons across the cytoplasmic membrane. the flagellar motor consists of ...201424970213
bacterial genus-specific tolerance for ydci expression.the bacterial ydci gene encodes a highly conserved transcriptional regulatory protein found in a wide range of gram-negative bacteria and is involved in a number of salmonella enterica serovar typhimurium phenotypes. given its high conservation, the ydci protein has the potential for studies and applications across bacterial genera. however, no studies have been performed with ydci outside of s. typhimurium. here we report that different gram-negative genera display dramatically different tolera ...201424962596
protozoan predation is differentially affected by motility of enteric pathogens in water vs. sediments.survival of enteric bacteria in aquatic habitats varies depending upon species, strain, and environmental pressures, but the mechanisms governing their fate are poorly understood. although predation by protozoa is a known, top-down control mechanism on bacterial populations, its influence on the survival of fecal-derived pathogens has not been systematically studied. we hypothesized that motility, a variable trait among pathogens, can influence predation rates and bacterial survival. we compared ...201424952019
gil, a new c-di-gmp-binding protein domain involved in regulation of cellulose synthesis in enterobacteria.in contrast to numerous enzymes involved in c-di-gmp synthesis and degradation in enterobacteria, only a handful of c-di-gmp receptors/effectors have been identified. in search of new c-di-gmp receptors, we screened the escherichia coli aska overexpression gene library using the differential radial capillary action of ligand assay (dracala) with fluorescently and radioisotope-labelled c-di-gmp. we uncovered three new candidate c-di-gmp receptors in e. coli and characterized one of them, bcse. th ...201424942809
atmospheric cold plasma inactivation of escherichia coli, salmonella enterica serovar typhimurium and listeria monocytogenes inoculated on fresh produce.atmospheric cold plasma (acp) represents a potential alternative to traditional methods for non-thermal decontamination of foods. in this study, the antimicrobial efficacy of a novel dielectric barrier discharge acp device against escherichia coli, salmonella enterica typhimurium and listeria monocytogenes inoculated on cherry tomatoes and strawberries, was examined. bacteria were spot inoculated on the produce surface, air dried and sealed inside a rigid polypropylene container. samples were in ...201424929725
characterization of extended-spectrum beta-lactamases-producing salmonella strains isolated from retail foods in shaanxi and henan province, china.extended-spectrum beta-lactamases (esbl)-producing salmonella enterica have been reported worldwide. however, research on foodborne esbl-producing salmonella has been rarely conducted. one hundred and thirty eight ceftriaxone or/and cefoperazone-resistant salmonella strains recovered from retail foods in shaanxi and henan province, china, were screened for esbl. the esbl-producing strains were further characterized for antimicrobial resistance, pulse field gel electrophoresis (pfge) profiles, an ...201424929711
modeling bacterial population growth from stochastic single-cell dynamics.a few bacterial cells may be sufficient to produce a food-borne illness outbreak, provided that they are capable of adapting and proliferating on a food matrix. this is why any quantitative health risk assessment policy must incorporate methods to accurately predict the growth of bacterial populations from a small number of pathogens. in this aim, mathematical models have become a powerful tool. unfortunately, at low cell concentrations, standard deterministic models fail to predict the fate of ...201424928885
efficient odd straight medium chain free fatty acid production by metabolically engineered escherichia coli.free fatty acids (ffas) can be used as precursors for the production of biofuels or chemicals. different composition of ffas will be useful for further modification of the biofuel/biochemical quality. microbial biosynthesis of even chain ffas can be achieved by introducing an acyl-acyl carrier protein thioesterase gene into e. coli. in this study, odd straight medium chain ffas production was investigated by using metabolic engineered e. coli carrying acyl-acp thioesterase (te, ricinus communis) ...201424889416
transcriptome dynamics-based operon prediction in prokaryotes.inferring operon maps is crucial to understanding the regulatory networks of prokaryotic genomes. recently, rna-seq based transcriptome studies revealed that in many bacterial species the operon structure vary with the change of environmental conditions. therefore, new computational solutions that use both static and dynamic data are necessary to create condition specific operon predictions.201424884724
molecular clonality and detection of class 1 integron in multidrug-resistant salmonella enterica isolates from animal and human in iran.a total of 70 multidrug-resistant (mdr) salmonella isolates (44 human and 26 poultry) were examined. the conserved segment-pcr, restriction fragment length polymorphism-pcr analysis, and dna sequencing were used to determine the presence and cassette content of integrons. the genetic relatedness among the isolates was examined by pulsed-field gel electrophoresis (pfge). the rate of integron carriage for mdr salmonella isolates was 91.4% and integron-positive isolates belonged to six distinct ser ...201424866249
effect of methylglyoxal on multidrug-resistant pseudomonas aeruginosa.honey has a complex chemistry, and its broad-spectrum antimicrobial activity varies with floral source, climate, and harvesting conditions. methylglyoxal was identified as the dominant antibacterial component of manuka honey. although it has been known that methylglyoxal has antibacterial activity against gram-positive bacteria, including methicillin-resistant staphylococcus aureus and vancomycin-resistant enterococcus, there is not much information describing its activity against gram-negative ...201424860556
characterization of 17 chaperone-usher fimbriae encoded by proteus mirabilis reveals strong conservation.proteus mirabilis is a gram-negative enteric bacterium that causes complicated urinary tract infections, particularly in patients with indwelling catheters. sequencing of clinical isolate p. mirabilis hi4320 revealed the presence of 17 predicted chaperone-usher fimbrial operons. we classified these fimbriae into three groups by their genetic relationship to other chaperone-usher fimbriae. sixteen of these fimbriae are encoded by all seven currently sequenced p. mirabilis genomes. the predicted p ...201424809384
in vitro evaluation of the mucin-adhesion ability and probiotic potential of lactobacillus mucosae lm1.in this report, we characterized the probiotic potential of lactobacillus mucosae lm1, focusing on its in vitro mucin-adhesion abilities.201424807045
decay of enteric microorganisms in biosolids-amended soil under wheat (triticum aestivum) cultivation.there is a growing need for better assessment of health risks associated with land-applied biosolids. this study investigated in-situ decay of seeded human adenovirus (hadv), salmonella enterica, escherichia coli, and bacteriophage (ms2) in biosolids-amended soil under wheat cultivation. the biosolids seeded with microorganisms were placed in decay chambers which were then placed in the topsoil (10 cm depth) at three different sites. sites were selected in arid wheat-growing regions of australia ...201424793663
the aerobic and anaerobic respiratory chain of escherichia coli and salmonella enterica: enzymes and energetics.escherichia coli contains a versatile respiratory chain that oxidizes 10 different electron donor substrates and transfers the electrons to terminal reductases or oxidases for the reduction of six different electron acceptors. salmonella is able to use two more electron acceptors. the variation is further increased by the presence of isoenzymes for some substrates. a large number of respiratory pathways can be established by combining different electron donors and acceptors. the respiratory dehy ...201426442941
transfer rna modification: presence, synthesis, and function.transfer rna (trna) from all organisms on this planet contains modified nucleosides, which are derivatives of the four major nucleosides. trna from escherichia coli/salmonella enterica serovar typhimurium contains 33 different modified nucleosides, which are all, except one (queuosine [q]), synthesized on an oligonucleotide precursor, which by specific enzymes later matures into trna. the structural genes for these enzymes are found in mono- and polycistronic operons, the latter of which have a ...201426442937
glycogen: biosynthesis and regulation.glycogen accumulation occurs in escherichia coli and salmonella enterica serovar typhimurium as well as in many other bacteria. glycogen will be formed when there is an excess of carbon under conditions in which growth is limited because of the lack of a growth nutrient, e.g., a nitrogen source. this review describes the enzymatic reactions involved in glycogen synthesis and the allosteric regulation of the first enzyme, adp-glucose pyrophosphorylase. the properties of the enzymes involved in gl ...201426442935
[efflux systems in serratia marcescens].a widespread bacterium serratia marcescens (family enterobacteriaceae) is an opportunistic and exhibits multiple drug resistance. active removal of antibiotics and other antimicrobials from pathogen and exhibits multiple drug resistance. active removal of antibiotics and other antimicrobials from the cells by efflux systems is one of the mechanisms responsible for microbial resistance to these compounds. among enterobacteria, efflux systems of escherichia coli and salmonella enterica var. typhim ...201425507452
enteric pathogens and antimicrobial resistance in turkey vultures (cathartes aura) feeding at the wildlife-livestock interface.free-flying turkey vultures (cathartes aura) were sampled in california to investigate the fecal shedding prevalence and antimicrobial susceptibility of salmonella enterica, campylobacter spp., and escherichia coli. nine different serotypes of salmonella enterica were detected in cloacal swabs from turkey vultures, and 6% of vultures were shedding campylobacter spp.. turkey vultures sampled at a location with range sheep were more likely to shed tetracycline-resistant e. coli, suggesting that pr ...201425632686
a versatile and highly efficient method for scarless genome editing in escherichia coli and salmonella enterica.recently developed methods for genome editing in bacteria take advantage of the introduction of double-strand breaks by i-scei in a mutation cassette to select for cells in which homologous recombination has healed the break and introduced a desired mutation. this elegantly designed method did not work well in our hands for most genes.201425255806
the antimicrobial efficacy of lippia alba essential oil and its interaction with food ingredients.the objective of this study was to evaluate the antimicrobial potential of lippia alba essential oil (eola) and to investigate the effect of food ingredients on its efficacy. the antimicrobial potential of the oil was determined by the presence or absence of inhibition zones, minimum inhibitory concentration (mic) and minimum bactericidal concentration (mbc) against escherichia coli, listeria innocua, listeria monocytogenes, pseudomonas aeruginosa, salmonella choleraesuis and staphylococcus aure ...201425242961
a novel, broad-range, ctxφ-derived stable integrative expression vector for functional studies.ctxφ, a filamentous vibriophage encoding cholera toxin, uses a unique strategy for its lysogeny. the single-stranded phage genome forms intramolecular base-pairing interactions between two inversely oriented xerc and xerd binding sites (xbs) and generates a functional phage attachment site, attp(+), for integration. the attp(+) structure is recognized by the host-encoded tyrosine recombinases xerc and xerd (xercd), which enables irreversible integration of ctxφ into the chromosome dimer resoluti ...201425225263
characterization of variants of the pore-forming toxin clya from escherichia coli controlled by a redox switch.the α-pore-forming toxin cytolysin a (clya) is responsible for the hemolytic phenotype of several escherichia coli and salmonella enterica strains. clya is a soluble, 34 kda monomer that assembles into a dodecameric pore complex in the presence of membranes or detergent. the comparison of the x-ray structures of monomeric clya and the clya protomer in the pore complex revealed one of the largest conformational transitions observed so far in proteins, involving the structural rearrangement of mor ...201425222267
the orphan regulator reid of salmonella enterica is essential for myo-inositol utilization.in salmonella enterica serovar typhimurium (s. typhimurium), the genomic island gei4417/4436 is responsible for the utilization of myo-inositol (mi) as carbon and energy source. here, we report the characterization of a novel, island-encoded positive autoregulator termed reid (stm4423) that is specific to certain s. enterica strains and escherichia coli strain ed1a able to use mi. reid was essential for growth with this polyol and also contributed to s. typhimurium proliferation in swine caecum ...201425213016
evaluation of nacl, ph, and lactic acid on the growth of shiga toxin-producing escherichia coli in a liquid cheddar cheese extract.a cheddar cheese model system, cheddar cheese extract, was used to examine how different levels of known microbial hurdles (nacl, ph, and lactic acid) in cheddar cheese contribute to inhibition of bacterial pathogens. this knowledge is critical to evaluate the safety of cheddar varieties with altered compositions. the range of levels used covered the lowest and highest level of these factors present in low-sodium, low-fat, and traditional cheddar cheeses. four pathogens were examined in this mod ...201425200778
effective control of salmonella infections by employing combinations of recombinant antimicrobial human β-defensins hbd-1 and hbd-2.we successfully produced two human β-defensins (hbd-1 and hbd-2) in bacteria as functional peptides and tested their antibacterial activities against salmonella enterica serovar typhi, escherichia coli, and staphylococcus aureus employing both spectroscopic and viable cfu count methods. purified peptides showed approximately 50% inhibition of the bacterial population when used individually and up to 90% when used in combination. the 50% lethal doses (ld50) of hbd-1 against s. typhi, e. coli, and ...201425199778
removal of salmonella enterica enteritidis and escherichia coli from green peppers and melons by ultrasound and organic acids.the aim of this study was to evaluate the effectiveness of ultrasound treatment combined with organic acids in the decontamination step for green peppers and melons. the influence of the surface roughness of the peppers and melons on bacterial adhesion was evaluated, as measured using a profilometer. the adhesion of salmonella enterica serovar enteritidis and escherichia coli to the green pepper and melon surfaces was also evaluated by measuring the hydrophobicity of the microorganisms and the s ...201425173914
application of dna aptamers and quantum dots to lateral flow test strips for detection of foodborne pathogens with improved sensitivity versus colloidal gold.preliminary studies aimed at improving the sensitivity of foodborne pathogen detection via lateral flow (lf) test strips by use of high affinity dna aptamers for capture and reporter functions when coupled to red-emitting quantum dots (qdot 655) are reported. a variety of dna aptamers developed against escherichia coli, listeria monocytogenes, and salmonella enterica were paired in capture and reporter combinations to determine which yielded the strongest detection of their cognate bacteria usin ...201425437803
[efflux systems in serratia marcescens].a widespread bacterium serratia marcescens (family enterobacteriaceae) is an opportunistic and exhibits multiple drug resistance. active removal of antibiotics and other antimicrobials from pathogen and exhibits multiple drug resistance. active removal of antibiotics and other antimicrobials from the cells by efflux systems is one of the mechanisms responsible for microbial resistance to these compounds. among enterobacteria, efflux systems of escherichia coli and salmonella enterica var. typhim ...201425423729
expression, purification, and in vitro comparative characterization of avian beta-defensin-2, -6, and -12.the mature peptides of avian β-defensin-2 (avbd-2), avbd-6, and avbd-12 were expressed as 6xhis-tagged recombinant proteins using the escherichia coli bl21(de3)plyss system. the yields of ravbd-2, ravbd-6, and ravbd-12 were approximately 0.92 mg/l, 1.24 mg/l, and 1.52 mg/l, respectively, of bacterial culture. the antimicrobial activities of ravbds were characterized under different salt, nutrient, and ph conditions. at concentrations of 8 μg/ml, 16 μg/ml, and 32 μg/ml, ravbds inhibited the growt ...201425618998
salmonella and escherichia coli contamination of poultry meat from a processing plant and retail markets in ibadan, oyo state, nigeria.salmonella spp and escherichia coli are the two most important food-borne pathogens of public health interest incriminated in poultry meat worldwide. this study is to access their levels in frozen poultry meat obtained in ibadan, oyo state and compare those obtained from a commercial nigerian-registered poultry company having a broiler-processing plant, sayed farms ltd(r), with that obtained from retail stores. these retail stores source their products as illegal imports from neighboring benin r ...201425674440
development of a novel cross-streaking method for isolation, confirmation, and enumeration of salmonella from irrigation ponds.the 2013 produce safety rules in food safety modernization act (fsma) require regular testing for generic escherichia coli in agricultural water intended for pre-harvest contact with the edible portion of fresh produce. however, the use of fecal contamination indicators frequently does not correctly reflect distribution of foodborne pathogens such as salmonella enterica, and ensuring food safety may require direct detection and enumeration of pathogens in agricultural settings. herein we report ...201424732066
sequence analysis of a ctx-m-1 inci1 plasmid found in salmonella 4,5,12:i:-, escherichia coli and klebsiella pneumoniae on a uk pig farm.in 2009, ctx-m enterobacteriaceae and salmonella isolates were recovered from a uk pig farm, prompting studies into the dissemination of the resistance and to establish any relationships between the isolates.201424729584
development of a pcr test system for specific detection of salmonella paratyphi b in foods.salmonella enterica serotype paratyphi b is a globally distributed human-specific pathogen causing paratyphoid fever. the aim of this study was to develop a rapid and reliable polymerase chain reaction (pcr) assay for its detection in food. the spab_01124 gene was found to be unique to s. paratyphi b using comparative genomics. primers for fragments of the spab_01124 gene and the salmonella-specific inva gene were used in combination to establish a multiplex pcr assay that showed 100% specificit ...201424725227
conjugal transfer of the pathogenicity island rod21 in salmonella enterica serovar enteritidis depends on environmental conditions.unstable pathogenicity islands are chromosomal elements that can be transferred from one bacterium to another. salmonella enterica serovar enteritidis (s. enteritidis) is a pathogenic bacterium containing such unstable pathogenicity islands. one of them, denominated rod21, is 26.5 kb in size and capable of excising from the chromosome in certain culture conditions, as well as during bacterial infection of phagocytic cells. in this study we have evaluated whether rod21 can be effectively transfer ...201424705125
a eukaryotic-like 3' untranslated region in salmonella enterica hild mrna.long 3' untranslated regions (3'utrs) are common in eukaryotic mrnas. in contrast, long 3'utrs are rare in bacteria, and have not been characterized in detail. we describe a 3'utr of 310 nucleotides in hild mrna, a transcript that encodes a transcriptional activator of salmonella enterica pathogenicity island 1 (spi-1). deletion of the hild 3'utr increases the hild mrna level, suggesting that the hild 3'utr may play a role in hild mrna turnover. cloning of the hild 3'utr downstream of the green ...201424682814
immersion in antimicrobial solutions reduces salmonella enterica and shiga toxin-producing escherichia coli on beef cheek meat.the objective of this study was to determine the effect of immersing beef cheek meat in antimicrobial solutions on the reduction of o157:h7 shiga toxin-producing escherichia coli (stec), non-o157:h7 stec, and salmonella enterica. beef cheek meat was inoculated with o157:h7 stec, non-o157:h7 stec, and s. enterica on both the adipose and muscle surfaces. the inoculated cheek meat was then immersed in one of seven antimicrobial solutions for 1, 2.5, or 5 min: (i) 1% aftec 3000 (aftec), (ii) 2.5% be ...201424680064
prevalence and concentration of bacterial pathogens in raw produce and minimally processed packaged salads produced in and for the netherlands.recent outbreaks with vegetable or fruits as vehicles have raised interest in the characterization of the public health risk due to microbial contamination of these commodities. because qualitative and quantitative data regarding prevalence and concentration of various microbes are lacking, we conducted a survey to estimate the prevalence and contamination level of raw produce and the resulting minimally processed packaged salads as sold in the netherlands. a dedicated sampling plan accounted fo ...201424674429
association of nuisance filamentous algae cladophora spp. with e. coli and salmonella in public beach waters: impacts of uv protection on bacterial survival.this study investigated whether filamentous algal species commonly found in nearshore public beach water systems provide protection from natural uv to bacteria present in the same environmental settings. to test this hypothesis, cladophora spp., a filamentous nuisance algae group causing undesired water quality in the great lakes region was selected and its interactions with a non-pathogenic indicator organism escherichia coli and a pathogenic strain of salmonella enterica serovar typhimurium we ...201424643370
rabbit monoclonal antibodies directed at the t3ss effector protein yopm identify human pathogenic yersinia isolates.the yersinia outer protein m (yopm) is a type 3 secretion system (t3ss)-dependent effector protein of yersinia enterocolitica, yersinia pseudotuberculosis and yersinia pestis. although yopm is indispensable for full virulence, its molecular functions still remain largely elusive. recently, we could identify the recombinant yopm (ryopm) protein derived from the y. enterocolitica strain 8081 (jb580) as a cell-penetrating protein, which down-regulates the expression of various pro-inflammatory cyto ...201424636859
prevalence of shiga toxin producing escherichia coli, salmonella enterica, and listeria monocytogenes at public access watershed sites in a california central coast agricultural region.produce contaminated with enteric pathogens is a major source of foodborne illness in the united states. lakes, streams, rivers, and ponds were sampled with moore swabs bi-monthly for over 2 years at 30 locations in the vicinity of a leafy green growing region on the central california coast and screened for shiga toxin producing escherichia coli (stec), salmonella enterica, and listeria monocytogenes to evaluate the prevalence and persistence of pathogen subtypes. the prevalence of stec from 13 ...201424624367
hydrophobic determinants of α-defensin bactericidal activity.mammalian α-defensins are approximately 4- to 5-kda broad-spectrum antimicrobial peptides and abundant granule constituents of neutrophils and small intestinal paneth cells. the bactericidal activities of amphipathic α-defensins depend in part on electropositive charge and on hydrophobic amino acids that enable membrane disruption by interactions with phospholipid acyl chains. alignment of α-defensin primary structures identified conserved hydrophobic residues in the loop formed by the cys(iii)- ...201424614658
ygae regulates out membrane proteins in salmonella enterica serovar typhi under hyperosmotic stress.salmonella enterica serovar typhi (s. typhi) is a human-specific pathogen that causes typhoid fever. in this study, we constructed δygae mutant and a microarray was performed to investigate the role of ygae in regulation of gene expression changes in response to hyperosmotic stress in s. typhi. qrt-pcr was performed to validate the microarray results. our data indicated that ygae was the repressor of gab operon in s. typhi as in escherichia coli (e. coli), though the sequence of ygae is totally ...201424592164
process optimization for increased yield of surface-expressed protein in escherichia coli.the autotransporter family of gram-negative protein exporters has been exploited for surface expression of recombinant passenger proteins. while the passenger in some cases was successfully translocated, a major problem has been low levels of full-length protein on the surface due to proteolysis following export over the cytoplasmic membrane. the aim of the present study was to increase the surface expression yield of the model protein sefa, a salmonella enterica fimbrial subunit with potential ...201424525833
antibiotic stress-induced modulation of the endoribonucleolytic activity of rnase iii and rnase g confers resistance to aminoglycoside antibiotics in escherichia coli.here, we report a resistance mechanism that is induced through the modulation of 16s ribosomal rna (rrna) processing on the exposure of escherichia coli cells to aminoglycoside antibiotics. we observed decreased expression levels of rnase g associated with increased rnase iii activity on rng mrna in a subgroup of e. coli isolates that transiently acquired resistance to low levels of kanamycin or streptomycin. analyses of 16s rrna from the aminoglycoside-resistant e. coli cells, in addition to mu ...201424489121
facile synthesis of tetrahydroprotoberberine and protoberberine alkaloids from protopines and study on their antibacterial activities.a series of isoquinoline alkaloids including tetrahydroprotoberberines, n-methyl tetrahydroprotoberberines and protoberberines were facile synthesised with protopines as the starting material. all compounds were evaluated for their antibacterial activities against four pathogenic bacteria escherichia coli, staphyloccocus aureus, staphylococcus gallinarum and salmonella choleraesuis. experimental results indicated that protoberberines were the most active compounds to the target bacteria among th ...201424422860
distinct roles of the salmonella enterica serovar typhimurium cyay and yggx proteins in the biosynthesis and repair of iron-sulfur clusters.labile [4fe-4s](2+) clusters found at the active sites of many dehydratases are susceptible to damage by univalent oxidants that convert the clusters to an inactive [3fe-4s](1+) form. bacteria repair damaged clusters in a process that does not require de novo protein synthesis or the isc and suf cluster assembly pathways. the current study investigates the participation of the bacterial frataxin ortholog cyay and the yggx protein, which are proposed to play roles in iron trafficking and iron-sul ...201424421039
inflammation fuels colicin ib-dependent competition of salmonella serovar typhimurium and e. coli in enterobacterial blooms.the host's immune system plays a key role in modulating growth of pathogens and the intestinal microbiota in the gut. in particular, inflammatory bowel disorders and pathogen infections induce shifts of the resident commensal microbiota which can result in overgrowth of enterobacteriaceae ("inflammation-inflicted blooms"). here, we investigated competition of the human pathogenic salmonella enterica serovar typhimurium strain sl1344 (s. tm) and commensal e. coli in inflammation-inflicted blooms. ...201424391500
thermal resistance of salmonella enterica, escherichia coli and staphylococcus aureus isolated from vegetable feed ingredients.cattle feed is at the beginning of the food chain in the 'farm-to-fork' model and might serve as a source of contamination with pathogenic bacteria. heat treatment is one of the most effective methods utilized to ensure the microbial safety of feeds. in this work, the thermal resistance of salmonella enterica, escherichia coli and staphylococcus aureus isolated from vegetable feed ingredients was investigated in phosphate-buffered saline (pbs) and in cattle feed.201424374973
salmonella enterica serovar enteritidis ghosts carrying the escherichia coli heat-labile enterotoxin b subunit are capable of inducing enhanced protective immune responses.the escherichia coli heat-labile enterotoxin b subunit (ltb) is a potent vaccine adjuvant. salmonella enterica serovar enteritidis ghosts carrying ltb (s. enteritidis-ltb ghosts) were genetically constructed using a novel plasmid, pjhl187-ltb, designed for the coexpression of the ltb and e lysis proteins. s. enteritidis-ltb ghosts were characterized using scanning electron microscopy to visualize their transmembrane tunnel structures. the expression of ltb in s. enteritidis-ltb ghost preparation ...201424671556
in vitro activity of rifaximin against clinical isolates of escherichia coli and other enteropathogenic bacteria isolated from travellers returning to the uk.rifaximin is licensed in the eu and usa for treating travellers' diarrhoea caused by non-invasive bacteria. selection for resistance mechanisms of public health significance might occur if these are linked to rifamycin resistance. rifaximin mics were determined by agar dilution for 90 isolates each of escherichia coli, shigella spp., nontyphoidal salmonella enterica, typhoidal s. enterica and campylobacter spp., an additional 60 e. coli with ctx-m esbls isolated from patients with travellers' di ...201424661532
periplasmic disulfide isomerase dsbc is involved in the reduction of copper binding protein cuep from salmonella enterica serovar typhimurium.salmonella enterica serovar typhimurium (s. typhimurium) is a facultative intracellular pathogen with the ability to survive and replicate in macrophages. periplasmic copper binding protein cuep is known to confer copper resistance to s. typhimurium, and has been implicated in ros scavenge activity by transferring the copper ion to a periplasmic superoxide dismutase or by directly reducing the copper ion. structural and biochemical studies on cuep showed that its copper binding site is surrounde ...201424657263
depuration times of donax trunculus and tapes decussatus.the present study was performed to determine the depuration time and ability of donax trunculus (wedge clam) and tapes decussatus (carpet shell) contaminated with escherichia coli, salmonella enterica subsp. enterica serovar typhimurium and vibrio parahaemolyticus. clams were contaminated with each bacterium at the level of 7.0 - 8.0 log10 cfu/g. after contamination, clams were analyzed every 3 h in the first 24 h time period and every 6 h until the 72nd hour. during the depuration process of bo ...201425477938
function of nucleoid-associated proteins in chromosome structuring and transcriptional regulation.nucleoid-associated proteins typically are abundant, low-molecular-mass polypeptides that bind dna and alter its shape and its ability to participate in transactions such as transcription. some can bind rna and influence the gene expression profile of the cell at a posttranscriptional level. they also have the potential to model and remodel the structure of the nucleoid, contributing to chromosome packaging within the cell. some nucleoid-associated proteins have been implicated in the facilitati ...201425732335
tailoring the probiotic potential of non-starter lactobacillus strains from ripened parmigiano reggiano cheese by in vitro screening and principal component analysis.non-starter lactic acid bacteria (nslab) inhabiting fermented food have been recently revised as source of probiotic strains. here, we in vitro assessed the potential probiotic aptitude of a de-replicated set of nslab previously isolated from long ripened parmigiano reggiano cheeses (22 lactobacillus rhamnosus, 18 lactobacillus paracasei, 3 lactobacillus casei, 2 lactobacillus harbinensis, and 2 lactobacillus fermentum). most strains showed moderate to good resistance to biological barriers, inc ...201424290648
in vitro effectiveness of the antimicrobial peptide ecath1 against antibiotic-resistant bacterial pathogens of horses.the equine antimicrobial peptide ecath1 previously has been shown to have in vitro activity against antibiotic-susceptible reference strains of rhodococcus equi and common respiratory bacterial pathogens of foals. interestingly, ecath1 was also found to be effective in the treatment of r. equi infection induced in mice. the aim of this study was to assess the in vitro activity of ecath1 against equine isolates of gram-negative (escherichia coli, salmonella enterica, klebsiella pneumoniae and pse ...201424279745
genome-scale analyses of escherichia coli and salmonella enterica arac reveal noncanonical targets and an expanded core regulon.escherichia coli arac is a well-described transcription activator of genes involved in arabinose metabolism. using complementary genomic approaches, chromatin immunoprecipitation (chip)-chip, and transcription profiling, we identify direct regulatory targets of arac, including five novel target genes: ytfq, yden, ydem, ygea, and polb. strikingly, only ytfq has an established connection to arabinose metabolism, suggesting that arac has a broader function than previously described. we demonstrate ...201424272778
genomic investigation of lysogen formation and host lysis systems of the salmonella temperate bacteriophage spn9cc.to understand phage infection and host cell lysis mechanisms in pathogenic salmonella, a novel salmonella enterica serovar typhimurium-targeting bacteriophage, spn9cc, belonging to the podoviridae family was isolated and characterized. the phage infects s. typhimurium via the o antigen of lipopolysaccharide (lps) and forms clear plaques with cloudy centers due to lysogen formation. phylogenetic analysis of phage major capsid proteins revealed that this phage is a member of the lysogen-forming p2 ...201424185850
inhibition of multidrug efflux as a strategy to prevent biofilm formation.we have recently shown that inactivation of any of the multidrug efflux systems of salmonella results in loss of the ability to form a competent biofilm. the aim of this study was to determine the mechanism linking multidrug efflux and biofilm formation, and to determine whether inhibition of efflux is a viable antibiofilm strategy.201424176982
decay of salmonella enterica, escherichia coli and bacteriophage ms2 on the phyllosphere and stored grains of wheat (triticum aestivum).cereal crops grown in the biosolids-amended soil can potentially become contaminated with pathogenic micro-organisms during growth and at the time of harvesting. there is small but unquantified potential risk of transfer of enteric pathogens to humans and animals from contaminated plants and grains. this study examined decay of escherichia coli, salmonella enterica serovar typhimurium and bacteriophage ms2 on the wheat phyllosphere and on stored grains. this was done to assess the health implica ...201423980794
ubij, a new gene required for aerobic growth and proliferation in macrophage, is involved in coenzyme q biosynthesis in escherichia coli and salmonella enterica serovar typhimurium.ubiquinone (coenzyme q or q8) is a redox active lipid which functions in the respiratory electron transport chain and plays a crucial role in energy-generating processes. in both escherichia coli and salmonella enterica serovar typhimurium, the yigp gene is located between ubie and ubib, all three being likely to constitute an operon. in this work, we showed that the uncharacterized yigp gene was involved in q8 biosynthesis in both strains, and we have renamed it ubij. under aerobic conditions, ...201424142253
targeting relaxase genes for classification of the predominant plasmids in enterobacteriaceae.plasmids are the main vectors of antimicrobial drug resistance and virulence genes, especially in enterobacteriaceae. identification and classification of plasmids is essential for analysis of their distribution. the most widely used typing method is pcr-based replicon typing (pbrt). a new classification scheme based on relaxase gene typing has been described recently. we propose a practical application of this method, with the development of a multiplex pcr set targeting relaxase genes found on ...201424342269
conformational changes of the bacterial type i atp-binding cassette importer hisqmp2 at distinct steps of the catalytic cycle.prokaryotic solute binding protein-dependent atp-binding cassette import systems are divided into type i and type ii and mechanistic differences in the transport process going along with this classification are under intensive investigation. little is known about the conformational dynamics during the catalytic cycle especially concerning the transmembrane domains. the type i transporter for positively charged amino acids from salmonella enterica serovar typhimurium (lao-hisqmp2) was studied by ...201424021237
the molecular adjuvant mc3d enhances the immunogenicity of fima from type i fimbriae of salmonella enterica serovar enteritidis.the fimbriae of salmonella enterica serovar enteritidis are used for colonization and invasion into host cells, and have drawn considerable interest because fimbriae can serve as potential immunogens against many pathogenic bacteria that colonize on epithelial surfaces. the purpose of the study is to use a molecular adjuvant, c3d, to enhance the immunogenicity of fima proteins against salmonella enterica serovar enteritidis.201423352331
carbon and clay nanoparticles induce minimal stress responses in gram negative bacteria and eukaryotic fish cells.we investigated in vitro the potential mutagenic and toxic effects of two clay-based nanoparticles, cloisite® na(+) (cloisite) and halloysite; and multi-walled carbon nanotubes (mwcnt), commonly used in the polymer composite industry. using the ames test, the three nanoparticles did not have a true mutagenic effect, although growth of salmonella enterica var. typhimurium (s.typhimurium) was diminished at higher nanoparticle concentrations. we investigated the impact of nanoparticles on escherich ...201423125163
use of enterococcus faecium as a surrogate for salmonella enterica during extrusion of a balanced carbohydrate-protein meal.multiple outbreaks of salmonellosis have been associated with the consumption of low-moisture products, including extruded products. therefore, there is a need for a nonpathogenic, surrogate microorganism that can be used to validate extrusion processes for salmonella. the objective of this research was to determine if enterococcus faecium nrrl b-2354 is an adequate surrogate organism for salmonella during extrusion. extrusions at different temperatures were done in material contaminated with bo ...201424406001
prevalence of the aminoglycoside phosphotransferase genes aph(3')-iiia and aph(3')-iia in escherichia coli, enterococcus faecalis, enterococcus faecium, pseudomonas aeruginosa, salmonella enterica subsp. enterica and staphylococcus aureus isolates in austria.the aminoglycoside phosphotransferase aph(3')-iia primarily inactivates kanamycin and neomycin, whilst aph(3')-iiia also inactivates amikacin. the aim of this study was to determine the frequency of both resistance genes in major human pathogens to obtain their baseline prevalence in the gene pool of these bacterial populations in austria. in total, 10 541 escherichia coli, enterococcus faecalis, enterococcus faecium, pseudomonas aeruginosa, salmonella enterica subsp. enterica and staphylococcus ...201424194558
characterization of some potentially probiotic lactobacillus strains isolated from iranian native chickens.the objective of the present study was to isolate, identify and characterize new lab strains with high probiotic potentials from iranian (isfahan) indigenous chickens. from 90 isolated labs, 11 isolates had high growth rate under different stress conditions, including acid (ph 2.5), bile (0.5% oxgall), salt (6-15%) and temperatures 15 and 45°c, and their aggregation time was less than 120 min. based on the molecular identification using 16s rdna sequencing and phylogenetic analysis, the isolates ...201425742971
next generation sequencing analysis of nine corynebacterium ulcerans isolates reveals zoonotic transmission and a novel putative diphtheria toxin-encoding pathogenicity island.toxigenic corynebacterium ulcerans can cause a diphtheria-like illness in humans and have been found in domestic animals, which were suspected to serve as reservoirs for a zoonotic transmission. additionally, toxigenic c. ulcerans were reported to take over the leading role in causing diphtheria in the last years in many industrialized countries.201425587356
high inhibition of paenibacillus larvae and listeria monocytogenes by enterococcus isolated from different sources in tunisia and identification of their bacteriocin genes.a total of 300 isolates of enterococcus, from different sources including faeces of poultry, cow and sheep, raw milk, ricotta cheese and water, in tunisia, were screened for their antibacterial activity. amongst them, 59 bacteriocin-producing strains were detected and identified by molecular methods. genes encoding for enta, entp, entb, entl50a/b, as-48 and bac31 bacteriocins were targeted by pcr. the bacteriocin-producing strains were assigned to the species enterococcus faecium, enterococcus f ...201424698417
molecular detection of avian pathogens in poultry red mite (dermanyssus gallinae) collected in chicken farms.poultry red mite (prm, dermanyssus gallinae) is a blood-sucking ectoparasite as well as a possible vector of several avian pathogens. in this study, to define the role of prm in the prevalence of avian infectious agents, we used polymerase chain reaction (pcr) to check for the presence of seven pathogens: avipox virus (apv), fowl adenovirus (fadv), marek's disease virus (mdv), erysipelothrix rhusiopathiae (er), salmonella enterica (se), mycoplasma synoviae (ms) and mycoplasma gallisepticum (mg). ...201425649939
monotreme lactation protein is highly expressed in monotreme milk and provides antimicrobial protection.monotremes (platypus and echidna) are the descendants of the oldest ancestor of all extant mammals distinguished from other mammals by mode of reproduction. monotremes lay eggs following a short gestation period and after an even briefer incubation period, altricial hatchlings are nourished over a long lactation period with milk secreted by nipple-less mammary patches located on the female's abdomen. milk is the sole source of nutrition and immune protection for the developing young until weanin ...201425245409
a comparison of conventional methods for the quantification of bacterial cells after exposure to metal oxide nanoparticles.due to potential interference of nanoparticles on bacterial quantification, there is a challenge to develop a fast, accurate and reproducible method for bacterial quantification. currently various bacterial quantification methods are used by researchers performing nanoparticles study, but there has been no efficacy evaluation of these methods. here we study interference of nanoparticles on three most commonly used conventional bacterial quantification methods, including colony counting to determ ...201425138641
in-vitro screening of malaysian honey from different floral sources for antibacterial activity on human pathogenic bacteria.different researches on therapeutic effects of honey have been conducted in different regions; however the study on the potential antibacterial activity of malaysian honey is still limited. in this study, antibacterial activities of different monofloral honey samples were tested against several common human pathogenic bacteria.201425435614
the role for tola in enterohemorrhagic escherichia coli pathogenesis and virulence gene transcription.loss of the periplasm spanning protein tola in escherichia coli leads to activation of the rcs phosphorelay, and is required for full virulence in gram-negative pathogens such as salmonella enterica and dickeya dadantii. this study explores the role for tola in the pathogenesis of enterohemorrhagic e. coli (ehec) and the effect of its mutation on the transcription of key ehec virulence genes controlled by rcs phosphorelay, including the type iii secretion system (t3ss) (espa and tir), the e. col ...201425448467
bacterial virulence and fis: adapting regulatory networks to the host environment.pathogenic bacteria have to cope with adverse conditions, such as the host environment and host defense reactions. to adapt quickly to environmental changes, pathogens have developed complex regulatory networks that ensure adequate expression of their virulence genes. recent evidence suggests that fis, an abundant nucleoid-associated protein transiently produced during early exponential growth, plays a major role in these networks in several pathogenic bacteria. this review focuses on two entero ...201424370464
cd4+ t cells: guardians of the phagosome.cd4(+) t cells are key cells of the adaptive immune system that use t cell antigen receptors to recognize peptides that are generated in endosomes or phagosomes and displayed on the host cell surface bound to major histocompatibility complex molecules. these t cells participate in immune responses that protect hosts from microbes such as mycobacterium tuberculosis, cryptococcus neoformans, leishmania major, and salmonella enterica, which have evolved to live in the phagosomes of macrophages and ...201424696433
green conversion of agroindustrial wastes into chitin and chitosan by rhizopus arrhizus and cunninghamella elegans strains.this article sets out a method for producing chitin and chitosan by cunninghamella elegans and rhizopus arrhizus strains using a green metabolic conversion of agroindustrial wastes (corn steep liquor and molasses). the physicochemical characteristics of the biopolymers and antimicrobial activity are described. chitin and chitosan were extracted by alkali-acid treatment, and characterized by infrared spectroscopy, viscosity and x-ray diffraction. the effectiveness of chitosan from c. elegans and ...201424853288
intestinal alkaline phosphatase prevents antibiotic-induced susceptibility to enteric pathogens.to determine the efficacy of oral supplementation of the gut enzyme intestinal alkaline phosphatase (iap) in preventing antibiotic-associated infections from salmonella enterica serovar typhimurium (s. typhimurium) and clostridium difficile.201423598380
survival of salmonella spp. and fecal indicator bacteria in vietnamese biogas digesters receiving pig slurry.small-scale biogas digesters are widely promoted worldwide as a sustainable technology to manage livestock manure. in vietnam, pig slurry is commonly applied to biogas digesters for production of gas for electricity and cooking with the effluent being used to fertilize field crops, vegetables and fish ponds. slurry may contain a variety of zoonotic pathogens, e.g. salmonella spp., which are able to cause disease in humans either through direct contact with slurry or by fecal contamination of wat ...201424933419
pathogen exclusion properties of canine probiotics are influenced by the growth media and physical treatments simulating industrial processes.manufacturing process used in preparation of probiotic products may alter beneficial properties of probiotics. the effect of different growth media and inactivation methods on the protective properties of canine-originated probiotic bacteria against adhesion of canine enteropathogens was investigated.201424779583
disease-outcome trees, eq-5d scores, and estimated annual losses of quality-adjusted life years (qalys) for 14 foodborne pathogens in the united states.measures of disease burden such as quality-adjusted life years (qalys) are increasingly important to risk-based food safety policy. they provide a means of comparing relative risk from diverse health outcomes. we present detailed disease-outcome trees and eq-5d scoring for 14 major foodborne pathogens representing over 95% of foodborne illnesses, hospitalizations, and deaths due to specified agents in the united states (campylobacter spp., clostridium perfringens, cryptosporidium parvum, cyclosp ...201424588853
enteropathogen co-infection in uk cats with diarrhoea.individual enteropathogen infections in healthy and clinically ill cats are well described, but prevalence and patterns of enteropathogen co-infection have only been reported on a limited basis. we studied enteropathogen co-infection in diarrhoeic uk cats using results of a real time pcr assay for 8 enteropathogenic species; feline coronavirus (co), feline panleukopenia virus (pa), clostridium perfringens (cl), salmonella enterica (sa), giardia spp. (gi), tritrichomonas foetus (tr), cryptosporid ...201424410914
lyn deficiency leads to increased microbiota-dependent intestinal inflammation and susceptibility to enteric pathogens.the lyn tyrosine kinase governs the development and function of various immune cells, and its dysregulation has been linked to malignancy and autoimmunity. using models of chemically induced colitis and enteric infection, we show that lyn plays a critical role in regulating the intestinal microbiota and inflammatory responses as well as protection from enteric pathogens. lyn(-/-) mice were highly susceptible to dextran sulfate sodium (dss) colitis, characterized by significant wasting, rectal bl ...201425339668
intestinal epithelium-specific myd88 signaling impacts host susceptibility to infectious colitis by promoting protective goblet cell and antimicrobial responses.intestinal epithelial cells (iecs), including secretory goblet cells, form essential physiochemical barriers that separate luminal bacteria from underlying immune cells in the intestinal mucosa. iecs are common targets for enteric bacterial pathogens, with hosts responding to these microbes through innate toll-like receptors that predominantly signal through the myd88 adaptor protein. in fact, myd88 signaling confers protection against several enteric bacterial pathogens, including salmonella en ...201424958710
gastrointestinal microbiota-mediated control of enteric pathogens.the gastrointestinal (gi) microbiota is a complex community of microorganisms residing within the mammalian gastrointestinal tract. the gi microbiota is vital to the development of the host immune system and plays a crucial role in human health and disease. the composition of the gi microbiota differs immensely among individuals yet specific shifts in composition and diversity have been linked to inflammatory bowel disease, obesity, atopy, and susceptibility to infection. in this review, we desc ...201425251855
an antibiotic-altered microbiota provides fuel for the enteric foe.antibiotic therapies disrupt the intestinal microbiota and render the host susceptible to enteric infections. a recent report by ng et al. explores the ability of two intestinal pathogens (salmonella enterica serovar typhimurium and clostridium difficile) to use this disruption to their advantage and consume host carbohydrates that would otherwise be unavailable in the presence of a normal gut microbiota.201424165893
cold-active antibacterial and antifungal activities and antibiotic resistance of bacteria isolated from an alpine hydrocarbon-contaminated industrial site.selection pressure in hydrocarbon-contaminated soils may lead not only to increased microbial resistance to antibiotics, but also to increased capacity of the soil indigenous population to produce antimicrobial compounds. therefore, we studied the antibiotic resistance pattern and antibacterial and/or antifungal activities of 47 bacterial strains isolated from an industrial alpine site heavily polluted with petroleum hydrocarbons. resistance to penicillin was more widespread (49%) than resistanc ...201424880083
a new ultrasonic high-throughput instrument for rapid dna release from microorganisms.rapid detection methods for microbiological contamination are requested by many industries that respond to public health concerns. the control laboratories are replacing traditional culturing methods with faster assays based on nucleic acid amplification technologies, such as real-time pcr. however, an optimal nucleic acid sample preparation method is critical for the sensitivity and specificity of such tools. a high-throughput automated external ultrasonic device was developed for rapid lysing ...201424548895
dual role of acidic diacetate sophorolipid as biostabilizer for zno nanoparticle synthesis and biofunctionalizing agent against salmonella enterica and candida albicans.in the present study, a yeast species isolated from cetp, vellore, tamilnadu was identified as cryptococcus sp. vitgbn2 based on molecular techniques and was found to be a potent producer of acidic diacetate sophorolipid in mineral salt media containing vegetable oil as additional carbon source. the chemical structure of the purified biosurfactant was identified as acidic diacetate sophorolipid through gc-ms analysis. this sophorolipid was used as a stabilizer for synthesis of zinc oxide nanopar ...201424150496
energetics of pathogenic bacteria and opportunities for drug development.the emergence and spread of drug-resistant pathogens and our inability to develop new antimicrobials to overcome resistance has inspired scientists to consider new targets for drug development. cellular bioenergetics is an area showing promise for the development of new antimicrobials, particularly in the discovery of new anti-tuberculosis drugs where several new compounds have entered clinical trials. in this review, we have examined the bioenergetics of various bacterial pathogens, highlightin ...201425476763
bacterial pathogen gene abundance and relation to recreational water quality at seven great lakes beaches.quantitative assessment of bacterial pathogens, their geographic variability, and distribution in various matrices at great lakes beaches are limited. quantitative pcr (qpcr) was used to test for genes from e. coli o157:h7 (eaeo157), shiga-toxin producing e. coli (stx2), campylobacter jejuni (mapa), shigella spp. (ipah), and a salmonella enterica-specific (se) dna sequence at seven great lakes beaches, in algae, water, and sediment. overall, detection frequencies were mapa>stx2>ipah>se>eaeo157. ...201425423586
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