Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| the acyl-homoserine lactone synthase yeni from yersinia enterocolitica modulates virulence gene expression in enterohemorrhagic escherichia coli o157:h7. | the human pathogen enterohemorrhagic escherichia coli (ehec) o157:h7 colonizes the rectoanal junction (raj) in cattle, its natural reservoir. colonization at the raj poses a serious risk for fecal shedding and contamination of the environment. we previously demonstrated that ehec senses acyl-homoserine lactones (ahls) produced by the microbiota in the rumen to activate the gad acid resistance genes necessary for survival through the acidic stomachs in cattle and to repress the locus of enterocyt ... | 2013 | 23980115 |
| bioinformatic prediction of gene functions regulated by quorum sensing in the bioleaching bacterium acidithiobacillus ferrooxidans. | the biomining bacterium acidithiobacillus ferrooxidans oxidizes sulfide ores and promotes metal solubilization. the efficiency of this process depends on the attachment of cells to surfaces, a process regulated by quorum sensing (qs) cell-to-cell signalling in many gram-negative bacteria. at. ferrooxidans has a functional qs system and the presence of ahls enhances its attachment to pyrite. however, direct targets of the qs transcription factor afer remain unknown. in this study, a bioinformatic ... | 2013 | 23959118 |
| lps structure and phoq activity are important for salmonella typhimurium virulence in the galleria mellonella infection model [corrected]. | the larvae of the wax moth, galleria mellonella, have been used experimentally to host a range of bacterial and fungal pathogens. in this study we evaluated the suitability of g. mellonella as an alternative animal model of salmonella infection. using a range of inoculum doses we established that the ld₅₀ of salmonellatyphimurium strain nctc 12023 was 3.6 × 10³ bacteria per larva. further, a set of isogenic mutant strains depleted of known virulence factors was tested to identify determinants es ... | 2013 | 23951347 |
| de-novo design of antimicrobial peptides for plant protection. | this work describes the de-novo design of peptides that inhibit a broad range of plant pathogens. four structurally different groups of peptides were developed that differ in size and position of their charged and hydrophobic clusters and were assayed for their ability to inhibit bacterial growth and fungal spore germination. several peptides are highly active at concentrations between 0,1 and 1 µg/ml against plant pathogenic bacteria, such as pseudomonas syringae, pectobacterium carotovorum, an ... | 2013 | 23951222 |
| the tip of the tail needle affects the rate of dna delivery by bacteriophage p22. | the p22-like bacteriophages have short tails. their virions bind to their polysaccharide receptors through six trimeric tailspike proteins that surround the tail tip. these short tails also have a trimeric needle protein that extends beyond the tailspikes from the center of the tail tip, in a position that suggests that it should make first contact with the host's outer membrane during the infection process. the base of the needle serves as a plug that keeps the dna in the virion, but role of th ... | 2013 | 23951045 |
| an acidic thermostable recombinant aspergillus nidulans endoglucanase is active towards distinct agriculture residues. | aspergillus nidulans is poorly exploited as a source of enzymes for lignocellulosic residues degradation for biotechnological purposes. this work describes the a. nidulans endoglucanase a heterologous expression in pichia pastoris, the purification and biochemical characterization of the recombinant enzyme. active recombinant endoglucanase a (reg a) was efficiently secreted as a 35 kda protein which was purified through a two-step chromatography procedure. the highest enzyme activity was detecte ... | 2013 | 23936633 |
| diverse antimicrobial interactions of halophilic archaea and bacteria extend over geographical distances and cross the domain barrier. | the significance of antimicrobial substances, halocins, produced by halophilic archaea and bacteria thriving in hypersaline environments is relatively unknown. it is suggested that their production might increase species diversity and give transient competitive advances to the producer strain. halocin production is considered to be common among halophilic archaea, but there is a lack of information about halocins produced by bacteria in highly saline environments. we studied the antimicrobial ac ... | 2013 | 23929527 |
| functional analysis of pgrp-la in drosophila immunity. | peptidoglycan recognition proteins (pgrps) are key regulators of the insect innate antibacterial response. even if they have been intensively studied, some of them have yet unknown functions. here, we present a functional analysis of pgrp-la, an as yet uncharacterized drosophila pgrp. the pgrp-la gene is located in cluster with pgrp-lc and pgrp-lf, which encode a receptor and a negative regulator of the imd pathway, respectively. structure predictions indicate that pgrp-la would not bind to pept ... | 2013 | 23922788 |
| new role for dcr-1/dicer in caenorhabditis elegans innate immunity against the highly virulent bacterium bacillus thuringiensis db27. | bacillus thuringiensis produces toxins that target invertebrates, including caenorhabditis elegans. virulence of bacillus strains is often highly specific, such that b. thuringiensis strain db27 is highly pathogenic to c. elegans but shows no virulence for another model nematode, pristionchus pacificus. to uncover the underlying mechanisms of the differential responses of the two nematodes to b. thuringiensis db27 and to reveal the c. elegans defense mechanisms against this pathogen, we conducte ... | 2013 | 23918784 |
| evaluation of the immunogenicity of campylobacter jejuni cjaa protein delivered by salmonella enterica sv. typhimurium strain with regulated delayed attenuation in chickens. | campylobacter spp. are regarded as the most common bacterial cause of gastroenteritis worldwide, and consumption of chicken meat contaminated by campylobacter is considered to be one of the most frequent sources of human infection in developed countries. here we evaluated the immunogenicity and protective efficacy of salmonella typhimurium χ9718 producing the campylobacter jejuni cjaa protein as a chicken anti-campylobacter vaccine. in this study chickens were orally immunized with a new generat ... | 2013 | 23913025 |
| evaluation of the immunogenicity of campylobacter jejuni cjaa protein delivered by salmonella enterica sv. typhimurium strain with regulated delayed attenuation in chickens. | campylobacter spp. are regarded as the most common bacterial cause of gastroenteritis worldwide, and consumption of chicken meat contaminated by campylobacter is considered to be one of the most frequent sources of human infection in developed countries. here we evaluated the immunogenicity and protective efficacy of salmonella typhimurium χ9718 producing the campylobacter jejuni cjaa protein as a chicken anti-campylobacter vaccine. in this study chickens were orally immunized with a new generat ... | 2013 | 23913025 |
| an easy, simple inexpensive test for the specific detection of pectobacterium carotovorum subsp. carotovorum based on sequence analysis of the pmra gene. | the species pectobacterium carotovorum includes a diverse subspecies of bacteria that cause disease on a wide variety of plants. in morocco, approximately 95% of the p. carotovorum isolates from potato plants with tuber soft rot are p. carotovorum subsp. carotovorum. however, identification of this pathogen is not always related to visual disease symptoms. this is especially true when different pathogen cause similar diseases on potato, citing as an example, p. carotovorum, p. atrosepticum and p ... | 2013 | 23890050 |
| dynamic chemical communication between plants and bacteria through airborne signals: induced resistance by bacterial volatiles. | certain plant growth-promoting rhizobacteria (pgpr) elicit induced systemic resistance (isr) and plant growth promotion in the absence of physical contact with plants via volatile organic compound (voc) emissions. in this article, we review the recent progess made by research into the interactions between pgpr vocs and plants, focusing on voc emission by pgpr strains in plants. particular attention is given to the mechanisms by which these bacterial vocs elicit isr. we provide an overview of rec ... | 2013 | 23881442 |
| mycorrhiza-induced resistance: more than the sum of its parts? | plants can develop an enhanced defensive capacity in response to infection by arbuscular mycorrhizal fungi (amf). this 'mycorrhiza-induced resistance' (mir) provides systemic protection against a wide range of attackers and shares characteristics with systemic acquired resistance (sar) after pathogen infection and induced systemic resistance (isr) following root colonisation by non-pathogenic rhizobacteria. it is commonly assumed that fungal stimulation of the plant immune system is solely respo ... | 2013 | 23871659 |
| biologically inspired strategies for combating bacterial biofilms. | infections caused by bacterial biofilms are a significant global health problem, causing considerable patient morbidity and mortality and contributing to the economic burden of infectious disease. this review describes diverse strategies to combat bacterial biofilms, focusing firstly on small molecule interference with bacterial communication and signaling pathways, including quorum sensing and two-component signal transduction systems. secondly we discuss enzymatic approaches to the degradation ... | 2013 | 23871261 |
| cell wall integrity: targeted post-synthetic modifications to reveal its role in plant growth and defense against pathogens. | the plant cell wall, a dynamic network of polysaccharides and glycoproteins of significant compositional and structural complexity, functions in plant growth, development and stress responses. in recent years, the existence of plant cell wall integrity (cwi) maintenance mechanisms has been demonstrated, but little is known about the signaling pathways involved, or their components. examination of key mutants has shed light on the relationships between cell wall remodeling and plant cell response ... | 2013 | 23857352 |
| quorum quenching in culturable phyllosphere bacteria from tobacco. | many gram-negative plant pathogenic bacteria employ a n-acylhomoserine lactone (ahl)-based quorum sensing (qs) system to regulate their virulence traits. a sustainable biocontrol strategy has been developed using quorum quenching (qq) bacteria to interfere with qs and protect plants from pathogens. here, the prevalence and the diversity of qq strains inhabiting tobacco leaf surfaces were explored. a total of 1177 leaf-associated isolates were screened for their ability to disrupt ahl-mediated qs ... | 2013 | 23857057 |
| new type of antimicrobial protein produced by the plant pathogen clavibacter michiganensis subsp. michiganensis. | it has previously been shown that the tomato pathogen clavibacter michiganensis subsp. michiganensis secretes a 14-kda protein, c. michiganensis subsp. michiganensis amp-i (cmmamp-i), that inhibits growth of clavibacter michiganensis subsp. sepedonicus, the causal agent of bacterial ring rot of potato. using sequences obtained from tryptic fragments, we have identified the gene encoding cmmamp-i and we have recombinantly produced the protein with an n-terminal intein tag. the gene sequence showe ... | 2013 | 23851100 |
| microbial diversity in the floral nectar of seven epipactis (orchidaceae) species. | floral nectar of animal-pollinated plants is commonly infested with microorganisms, yet little is known about the microorganisms inhabiting the floral nectar of orchids. in this study, we investigated microbial communities occurring in the floral nectar of seven epipactis (orchidaceae) species. culturable bacteria and yeasts were isolated and identified by partially sequencing the small subunit (ssu) ribosomal rna (rrna) gene and the d1/d2 domains of the large subunit (lsu) rrna gene, respective ... | 2013 | 23836678 |
| a design principle of group-level decision making in cell populations. | populations of cells often switch states as a group to cope with environmental changes such as nutrient availability and cell density. although the gene circuits that underlie the switches are well understood at the level of single cells, the ways in which such circuits work in concert among many cells to support group-level switches are not fully explored. experimental studies of microbial quorum sensing show that group-level changes in cellular states occur in either a graded or an all-or-none ... | 2013 | 23825937 |
| addition of a carbohydrate-binding module enhances cellulase penetration into cellulose substrates. | cellulases are of great interest for application in biomass degradation, yet the molecular details of the mode of action of glycoside hydrolases during degradation of insoluble cellulose remain elusive. to further improve these enzymes for application at industrial conditions, it is critical to gain a better understanding of not only the details of the degradation process, but also the function of accessory modules. | 2013 | 23819686 |
| release of proteins from intact chloroplasts induced by reactive oxygen species during biotic and abiotic stress. | plastids sustain life on this planet by providing food, feed, essential biomolecules and oxygen. such diverse metabolic and biosynthetic functions require efficient communication between plastids and the nucleus. however, specific factors, especially large molecules, released from plastids that regulate nuclear genes have not yet been fully elucidated. when tobacco and lettuce transplastomic plants expressing gfp within chloroplasts, were challenged with erwinia carotovora (biotic stress) or par ... | 2013 | 23799142 |
| [catalytic properties of enzymes from erwinia carotovora involved in transamination of phenylpyruvate]. | km for l-phenylalanine, l-glutamic acid, l-aspartic acid, and the corresponding keto acids were calculated, as well as vmax, was measured for the following pairs of substrates: l-phenylalanine-2-ketoglutarate, l-phenylalanine-oxaloacetate, l-glutamic acid-phenylpyruvate, and l-aspartic acid-phenylpyruvate for aminotransferases pati, pat2, and pat3 from erwinia carotovora catalyzing transamination of phenylpyruvate. the ping-pong bi-bi mechanism was shown for the studied aminotransferases. the su ... | 2016 | 23795470 |
| [recombinant intracellular rhodospirillum rubrum l-asparaginase with low l-glutaminase activity and antiproliferative effect]. | the recombinant producer of rhodospirillum rubrum l-asparaginase (rra) was received and purification procedure of rra was developed. it was shown that rra has following biochemical and catalytic characteristics: k(m) for l-asn 0.22 mm, ph optimum 9.2; temperature optimum 54 degrees c; pi = 5.1 +/- 0.3; l-gln activity seems to be low-to-negligible. k562, du145 and mda-mb-231 cellular lines displayed significant sensitivity towards the enzyme (ic50 = 1.80; 9.19 and 34.62 me/ml, respectively. in co ... | 2014 | 23789346 |
| biochemical characterization of udp-n-acetylmuramoyl-l-alanyl-d-glutamate: meso-2,6-diaminopimelate ligase (mure) from verrucomicrobium spinosum dsm 4136(t.). | verrucomicrobium spinosum is a gram-negative bacterium that is related to bacteria from the genus chlamydia. the bacterium is pathogenic towards drosophila melanogaster and caenorhabditis elegans, using a type iii secretion system to facilitate pathogenicity. v. spinosum employs the recently discovered l,l-diaminopimelate aminotransferase biosynthetic pathway to generate the bacterial cell wall and protein precursors diaminopimelate and lysine. a survey of the v. spinosum genome provides evidenc ... | 2013 | 23785498 |
| mutations in the imd pathway and mustard counter vibrio cholerae suppression of intestinal stem cell division in drosophila. | vibrio cholerae is an estuarine bacterium and an intestinal pathogen of humans that causes severe epidemic diarrhea. in the absence of adequate mammalian models in which to study the interaction of v. cholerae with the host intestinal innate immune system, we have implemented drosophila melanogaster as a surrogate host. we previously showed that immune deficiency pathway loss-of-function and mustard gain-of-function mutants are less susceptible to v. cholerae infection. we find that although the ... | 2013 | 23781070 |
| quorum sensing and phytochemicals. | most infectious diseases are caused by bacteria, which proliferate within quorum sensing (qs)-mediated biofilms. efforts to block qs in bacteria and disrupt biofilms have enabled the identification of bioactive molecules that are also produced by plants. this mini review primarily focuses on natural qs inhibitors, which display potential for treating bacterial infections and also enhance the safety of food supply. | 2013 | 23774835 |
| polymyxin p is the active principle in suppressing phytopathogenic erwinia spp. by the biocontrol rhizobacterium paenibacillus polymyxa m-1. | nine gene clusters dedicated to nonribosomal synthesis of secondary metabolites with possible antimicrobial action, including polymyxin and fusaricidin, were detected within the whole genome sequence of the plant growth-promoting rhizobacterium (pgpr) paenibacillus polymyxa m-1. to survey the antimicrobial compounds expressed by m-1 we analyzed the active principle suppressing phytopathogenic erwinia spp. | 2013 | 23773687 |
| discovery of plant phenolic compounds that act as type iii secretion system inhibitors or inducers of the fire blight pathogen, erwinia amylovora. | erwinia amylovora causes a devastating disease called fire blight in rosaceous plants. the type iii secretion system (t3ss) is one of the important virulence factors utilized by e. amylovora in order to successfully infect its hosts. by using a green fluorescent protein (gfp) reporter construct combined with a high-throughput flow cytometry assay, a library of phenolic compounds and their derivatives was studied for their ability to alter the expression of the t3ss. based on the effectiveness of ... | 2013 | 23770912 |
| the pathochip, a functional gene array for assessing pathogenic properties of diverse microbial communities. | pathogens present in the environment pose a serious threat to human, plant and animal health as evidenced by recent outbreaks. as many pathogens can survive and proliferate in the environment, it is important to understand their population dynamics and pathogenic potential in the environment. to assess pathogenic potential in diverse habitats, we developed a functional gene array, the pathochip, constructed with key virulence genes related to major virulence factors, such as adherence, colonizat ... | 2013 | 23765101 |
| identification of another module involved in the horizontal transfer of the haemophilus genomic island icehin1056. | a significant part of horizontal gene transfer is facilitated by genomic islands. haemophilus influenzae genomic island icehin1056 is an archetype of a genomic island that accounts for pandemic spread of antibiotics resistance. icehin1056 has modular structure and harbors modules involved in type iv secretion and integration. previous studies have shown that icehin1056 encodes a functional type iv secretion system; however, other modules have not been characterized yet. here we show that the mod ... | 2013 | 23764277 |
| inactivation of ahls by ochrobactrum sp. a44 depends on the activity of a novel class of ahl acylase. | the soil isolate ochrobactrum sp. a44 inactivates n-acyl homoserine lactone (ahl) quorum sensing signal molecules and is capable of quenching the ahl-dependent virulence of pectobacterium carotovorum in planta. to characterize this ahl inactivating activity, ochrobactrum cell extracts were prepared and their capacity to degrade a broad range of ahls was determined. ahls with acyl chains ranging from c4 to c14 with or without 3-oxo or 3-hydroxy substituents were all inactivated to varying extents ... | 2011 | 23761232 |
| inferring ancient metabolism using ancestral core metabolic models of enterobacteria. | enterobacteriaceae diversified from an ancestral lineage ~300-500 million years ago (mya) into a wide variety of free-living and host-associated lifestyles. nutrient availability varies across niches, and evolution of metabolic networks likely played a key role in adaptation. | 2013 | 23758866 |
| colonization patterns of an mcherry-tagged pectobacterium carotovorum subsp. brasiliense strain in potato plants. | pectobacterium carotovorum subsp. brasiliense is a newly identified member of the potato soft rot enterobacteriaceae. the pathogenesis of this pathogen is still poorly understood. in this study, an mcherry-p. carotovorum subsp. brasiliense-tagged strain was generated to study p. carotovorum subsp. brasiliense-potato plant interactions. prior to use, the tagged strain was evaluated for in vitro growth, plasmid stability, and virulence on potato tubers and shown to be similar to the wild type. fou ... | 2013 | 23758294 |
| the type iii secreted effector dspe is required early in solanum tuberosum leaf infection by pectobacterium carotovorum to cause cell death, and requires wx(3-6)d/e motifs. | pectobacterium species are enterobacterial plant-pathogens that cause soft rot disease in diverse plant species. unlike hemi-biotrophic plant pathogenic bacteria, the type iii secretion system (t3ss) of pectobacterium carotovorum subsp. carotovorum (p. carotovorum) appears to secrete only one effector protein, dspe. previously, we found that the t3ss regulator hrpl and the effector dspe are required for p. carotovorum pathogenesis on leaves. here, we identified genes up-regulated by hrpl, visual ... | 2013 | 23755246 |
| molecular characterization of the bacterial community in a potato phytosphere. | the bacterial community of a potato phytosphere at the flowering stage was examined using both culture-dependent and -independent methods. tissues (leaves, stems, roots and tubers) were sampled from field-grown potato plants (cultivar matilda), and the clone libraries of 16s rrna genes and the isolate collections using r2a medium were constructed. by analyzing the combined data set of 16s rrna gene sequences from both clone libraries and isolate collections, 82 genera from 8 phyla were found and ... | 2013 | 23748858 |
| genome microscale heterogeneity among wild potatoes revealed by diversity arrays technology marker sequences. | tuber-bearing potato species possess several genes that can be exploited to improve the genetic background of the cultivated potato solanum tuberosum. among them, s. bulbocastanum and s. commersonii are well known for their strong resistance to environmental stresses. however, scant information is available for these species in terms of genome organization, gene function, and regulatory networks. consequently, genomic tools to assist breeding are meager, and efficient exploitation of these speci ... | 2013 | 23738318 |
| e. coli-derived l-asparaginase retains enzymatic and cytotoxic activity in vitro for canine and feline lymphoma after cold storage. | background. l-asparaginase is effective in treating canine and feline lymphoma, however chemotherapy poses a significant financial cost to veterinary clients, limiting therapy for many pets. single dose vials result in significant drug wastage, and drug shortages limit consistent availability for pets. hypothesis. e. coli-derived asparaginase retains enzymatic and antineoplastic activity in canine and feline lymphoma cells after cold storage. methods. e. coli-derived asparaginase was cold-stored ... | 2013 | 23738234 |
| injury-induced bmp signaling negatively regulates drosophila midgut homeostasis. | although much is known about injury-induced signals that increase rates of drosophila melanogaster midgut intestinal stem cell (isc) proliferation, it is largely unknown how isc activity returns to quiescence after injury. in this paper, we show that the bone morphogenetic protein (bmp) signaling pathway has dual functions during midgut homeostasis. constitutive bmp signaling pathway activation in the middle midgut mediated regional specification by promoting copper cell differentiation. in the ... | 2013 | 23733344 |
| biocontrol of pectobacterium carotovorum subsp. carotovorum using bacteriophage pp1. | pectobacterium carotovorum subsp. carotovorum (formerly erwinia carotovora subsp. carotovora) is a plant pathogen that causes soft rot and stem rot diseases in several crops, including chinese cabbage, potato, and tomato. to control this bacterium, we isolated a bacteriophage, pp1, with lytic activity against p. carotovorum subsp. carotovorum. transmission electron microscopy revealed that the pp1 phage belongs to the podoviridae family of the order caudovirales, which exhibit icosahedral heads ... | 2013 | 23727798 |
| expression and efficient secretion of a functional chitinase from chromobacterium violaceum in escherichia coli. | chromobacterium violaceum is a free-living β-proteobacterium found in tropical and subtropical regions. the genomic sequencing of c. violaceum atcc 12472 has revealed many genes that underpin its adaptability to diverse ecosystems. moreover, c. violaceum genes with potential applications in industry, medicine and agriculture have also been identified, such as those encoding chitinases. however, none of the chitinase genes of the atcc 12472 strain have been subjected to experimental validation. c ... | 2013 | 23725035 |
| the drosophila imd pathway in the activation of the humoral immune response. | the imd pathway signaling plays a pivotal role in the drosophila defense against bacteria. during the last two decades, significant progress has been made in identifying the components and deciphering the molecular mechanisms underlying this pathway, including the means of bacterial sensing and signal transduction. while these findings have contributed to the understanding of the immune signaling in insects, they have also provided new insights in studying the mammalian nf-κb signaling pathways. ... | 2013 | 23721820 |
| the drosophila imd pathway in the activation of the humoral immune response. | the imd pathway signaling plays a pivotal role in the drosophila defense against bacteria. during the last two decades, significant progress has been made in identifying the components and deciphering the molecular mechanisms underlying this pathway, including the means of bacterial sensing and signal transduction. while these findings have contributed to the understanding of the immune signaling in insects, they have also provided new insights in studying the mammalian nf-κb signaling pathways. ... | 2013 | 23721820 |
| the fire blight pathogen erwinia amylovora requires the rpon gene for pathogenicity in apple. | rpon is a σ(54) factor regulating essential virulence gene expression in several plant pathogenic bacteria, including pseudomonas syringae and pectobacterium carotovorum. in this study, we found that mutation of rpon in the fire blight pathogen erwinia amylovora caused a nonpathogenic phenotype. the e. amylovora rpon tn5 transposon mutant rpon1250::tn5 did not cause fire blight disease symptoms on shoots of mature apple trees. in detached immature apple fruits, the rpon1250::tn5 mutant failed to ... | 2013 | 23721085 |
| interference of bacterial cell-to-cell communication: a new concept of antimicrobial chemotherapy breaks antibiotic resistance. | bacteria use a cell-to-cell communication activity termed "quorum sensing" to coordinate group behaviors in a cell density dependent manner. quorum sensing influences the expression profile of diverse genes, including antibiotic tolerance and virulence determinants, via specific chemical compounds called "autoinducers". during quorum sensing, gram-negative bacteria typically use an acylated homoserine lactone (ahl) called autoinducer 1. since the first discovery of quorum sensing in a marine bac ... | 2013 | 23720655 |
| two volatile organic compounds trigger plant self-defense against a bacterial pathogen and a sucking insect in cucumber under open field conditions. | systemic acquired resistance (sar) is a plant self-defense mechanism against a broad-range of pathogens and insect pests. among chemical sar triggers, plant and bacterial volatiles are promising candidates for use in pest management, as these volatiles are highly effective, inexpensive, and can be employed at relatively low concentrations compared with agrochemicals. however, such volatiles have some drawbacks, including the high evaporation rate of these compounds after application in the open ... | 2013 | 23698768 |
| antibiofilm activity of actinobacillus pleuropneumoniae serotype 5 capsular polysaccharide. | cell-free extracts isolated from colony biofilms of actinobacillus pleuropneumoniae serotype 5 were found to inhibit biofilm formation by staphylococcus aureus, s. epidermidis and aggregatibacter actinomycetemcomitans, but not by a. pleuropneumoniae serotype 5 itself, in a 96-well microtiter plate assay. physical and chemical analyses indicated that the antibiofilm activity in the extract was due to high-molecular-weight polysaccharide. extracts isolated from a mutant strain deficient in the pro ... | 2013 | 23691104 |
| efficacy of aiim, an n-acylhomoserine lactonase, against pseudomonas aeruginosa in a mouse model of acute pneumonia. | quorum sensing (qs) in pseudomonas aeruginosa regulates the production of many virulence factors and plays an important role in the pathogenesis of p. aeruginosa infection. n-acyl homoserine lactones (ahl) are major qs signal molecules. recently, a novel ahl-lactonase enzyme, aiim, has been identified. the aim of this study was to evaluate the effect of aiim on the virulence of p. aeruginosa in a mouse model of acute pneumonia. we developed a p. aeruginosa pao1 strain harboring an aiim-expressin ... | 2013 | 23689715 |
| broad host range vectors for expression of proteins with (twin-) strep-tag, his-tag and engineered, export optimized yellow fluorescent protein. | in current protein research, a limitation still is the production of active recombinant proteins or native protein associations to assess their function. especially the localization and analysis of protein-complexes or the identification of modifications and small molecule interaction partners by co-purification experiments requires a controllable expression of affinity- and/or fluorescence tagged variants of a protein of interest in its native cellular background. advantages of periplasmic and/ ... | 2013 | 23687945 |
| characterization of genes required for the pathogenicity of pectobacterium carotovorum subsp. carotovorum pcc21 in chinese cabbage. | pectobacterium carotovorum subsp. carotovorum is a well-known plant pathogen that causes severe soft rot disease in various crops, resulting in considerable economic loss. to identify pathogenicity-related factors, chinese cabbage was inoculated with 5314 transposon mutants of p. carotovorum subsp. carotovorum pcc21 derived using tn5 transposon mutagenesis. a total of 35 reduced-virulence or avirulent mutants were isolated, and 14 loci were identified. the 14 loci could be functionally grouped i ... | 2013 | 23676432 |
| lectin receptor kinases in plant innate immunity. | a key feature of innate immunity is the ability to recognize and respond to potential pathogens in a highly sensitive and specific manner. in plants, the first layer of defense is induced after recognition by pattern recognition receptors of microbe-associated molecular patterns. this recognition elicits a defense program known as pattern-triggered immunity. pathogen entry into host tissue is a critical early step in causing infection. for foliar bacterial pathogens, natural surface openings suc ... | 2013 | 23675375 |
| effect of signal peptide on stability and folding of escherichia coli thioredoxin. | the signal peptide plays a key role in targeting and membrane insertion of secretory and membrane proteins in both prokaryotes and eukaryotes. in e. coli, recombinant proteins can be targeted to the periplasmic space by fusing naturally occurring signal sequences to their n-terminus. the model protein thioredoxin was fused at its n-terminus with male and pelb signal sequences. while wt and the pelb fusion are soluble when expressed, the male fusion was targeted to inclusion bodies and was refold ... | 2013 | 23667620 |
| ecdysone triggered pgrp-lc expression controls drosophila innate immunity. | throughout the animal kingdom, steroid hormones have been implicated in the defense against microbial infection, but how these systemic signals control immunity is unclear. here, we show that the steroid hormone ecdysone controls the expression of the pattern recognition receptor pgrp-lc in drosophila, thereby tightly regulating innate immune recognition and defense against bacterial infection. we identify a group of steroid-regulated transcription factors as well as two gata transcription facto ... | 2013 | 23652443 |
| the pvc operon regulates the expression of the pseudomonas aeruginosa fimbrial chaperone/usher pathway (cup) genes. | the pseudomonas aeruginosa fimbrial structures encoded by the cup gene clusters (cupb and cupc) contribute to its attachment to abiotic surfaces and biofilm formation. the p. aeruginosa pvcabcd gene cluster encodes enzymes that synthesize a novel isonitrile functionalized cumarin, paerucumarin. paerucumarin has already been characterized chemically, but this is the first report elucidating its role in bacterial biology. we examined the relationship between the pvc operon and the cup gene cluster ... | 2013 | 23646138 |
| seasonal variation in functional properties of microbial communities in beech forest soil. | substrate quality and the availability of nutrients are major factors controlling microbial decomposition processes in soils. seasonal alteration in resource availability, which is driven by plants via belowground c allocation, nutrient uptake and litter fall, also exerts effects on soil microbial community composition. here we investigate if seasonal and experimentally induced changes in microbial community composition lead to alterations in functional properties of microbial communities and th ... | 2013 | 23645937 |
| dissecting the metal selectivity of merr monovalent metal ion sensors in salmonella. | two homologous transcription factors, cuer and gols, that belong to the merr metalloregulatory family are responsible for salmonella cu and au sensing and resistance, respectively. they share similarities not only in their sequences, but also in their target transcription binding sites. while cuer responds similarly to au, ag, or cu to induce the expression of its target genes, gols shows higher activation by au than by ag or cu. we showed that the ability of gols to distinguish au from cu resid ... | 2013 | 23645605 |
| mechanisms and consequence of bacteria detection by the drosophila gut epithelium. | since insect mostly developed on decaying matter and contaminated fruits, they are constantly ingesting bacteria. the insect model, drosophila, is therefore well adapted to study the interactions that take place between the gut epithelia and either resident or infectious bacteria. in order to provide an ad hoc immune response, gut epithelial cells must detect the presence of bacteria. in a recent report, bosco-drayon et al. identify the main receptors by which drosophila sense gut associated bac ... | 2013 | 23633672 |
| mapping and regulation of genes within salmonella pathogenicity island 12 that contribute to in vivo fitness of salmonella enterica serovar typhimurium. | salmonella pathogenicity island 12 (spi-12) of salmonella enterica serovar typhimurium is a 15-kb region that encompasses genes stm2230 to stm2245 and encodes a remnant phage known to contribute to bacterial virulence. in mouse infection experiments and replication assays in macrophages, we demonstrated a role for four genes in spi-12 for bacterial survival in the host. stm2239, a potential q antiterminator, showed a prominent contribution to bacterial fitness. transcriptional reporter experimen ... | 2013 | 23630960 |
| structural basis for hypermodification of the wobble uridine in trna by bifunctional enzyme mnmc. | methylaminomethyl modification of uridine or 2-thiouridine (mnm5u34 or mnm5s2u34) at the wobble position of trnas specific for glutamate, lysine and arginine are observed in escherichia coli and allow for specific recognition of codons ending in a or g. in the biosynthetic pathway responsible for this post-transcriptional modification, the bifunctional enzyme mnmc catalyzes the conversion of its hypermodified substrate carboxymethylaminomethyl uridine (cmnm5u34) to mnm5u34. mnmc catalyzes the fl ... | 2013 | 23617613 |
| bioactive molecules in soil ecosystems: masters of the underground. | complex biological and ecological processes occur in the rhizosphere through ecosystem-level interactions between roots, microorganisms and soil fauna. over the past decade, studies of the rhizosphere have revealed that when roots, microorganisms and soil fauna physically contact one another, bioactive molecular exchanges often mediate these interactions as intercellular signal, which prepare the partners for successful interactions. despite the importance of bioactive molecules in sustainable a ... | 2013 | 23615474 |
| mechanistic insights into the bifunctional non-heme iron oxygenase carbapenem synthase by active site saturation mutagenesis. | the carbapenem class of β-lactam antibiotics is known for its remarkable potency, antibacterial spectrum, and resistance to β-lactamase-mediated inactivation. while the biosynthesis of structurally "complex" carbapenems, such as thienamycin, share initial biochemical steps with carbapenem-3-carboxylate ("simple" carbapenem), the requisite inversion at c5 and formation of the characteristic α,β-unsaturated carboxylate are different in origin between the two groups. here, we consider carbapenem sy ... | 2013 | 23611403 |
| enhanced biocidal activity of au nanoparticles synthesized in one pot using 2, 4-dihydroxybenzene carbodithioic acid as a reducing and stabilizing agent. | the conjugation of gold nanoparticles with biocides such as natural products, oligosaccharides, dna, proteins has attracted great attention of scientists recently. gold nps covered with biologically important molecules showed significant enhancement in biological activity in comparison with the activity of the free biocides. however, these reports are not very systematic and do not allow to draw definitive conclusions. we therefore embarked in a systematic study related to the synthesis and char ... | 2013 | 23607626 |
| one shot-two pathogens blocked: exposure of arabidopsis to hexadecane, a long chain volatile organic compound, confers induced resistance against both pectobacterium carotovorum and pseudomonas syringae. | bacteria and plant derived volatile organic compounds have been reported as the chemical triggers that elicit induced resistance in plants. previously, volatile organic compounds (vocs), including acetoin and 2,3-butanediol, were found to be emitted from plant growth-promoting rhizobacteria (pgpr) bacillus subtilis gb03, which had been shown to elicit isr and plant growth promotion. more recently, we reported data that stronger induced resistance could be elicited against pseudomonas syringae pv ... | 2013 | 23603940 |
| drybp contributes to the negative regulation of the drosophila imd pathway. | the drosophila humoral innate immune response fights infection by producing antimicrobial peptides (amps) through the microbe-specific activation of the toll or the imd signaling pathway. upon systemic infection, the production of amps is both positively and negatively regulated to reach a balanced immune response required for survival. here, we report the function of the drybp (drosophila ring and yy1 binding protein) protein, which contains a ubiquitin-binding domain, in the imd pathway. we ha ... | 2013 | 23596533 |
| synthesis, characterization, in vitro antimicrobial, and u2os tumoricidal activities of different coumarin derivatives. | coumarin and its derivatives are biologically very active. it was found that the enhanced activities are dependent on the coumarin nucleus. biological significance of these compounds include anti-bacterial, anti-thrombotic and vasodilatory, anti-mutagenic, lipoxygenase and cyclooxygenase inhibition, scavenging of reactive oxygen species, and anti-tumourigenic. our interest in medicinal chemistry of dicoumarol compounds have been developed by keeping in view the importance of coumarins along with ... | 2013 | 23587363 |
| wound-induced pectin methylesterases enhance banana (musa spp. aaa) susceptibility to fusarium oxysporum f. sp. cubense. | recent studies suggest that plant pectin methylesterases (pmes) are directly involved in plant defence besides their roles in plant development. however, the molecular mechanisms of pme action on pectins are not well understood. in order to understand how pmes modify pectins during banana (musa spp.)-fusarium interaction, the expression and enzyme activities of pmes in two banana cultivars, highly resistant or susceptible to fusarium, were compared with each other. furthermore, the spatial distr ... | 2013 | 23580752 |
| the hemophore hasa from yersinia pestis (hasayp) coordinates hemin with a single residue, tyr75, and with minimal conformational change. | hemophores from serratia marcescens (hasa(sm)) and pseudomonas aeruginosa (hasa(p)) bind hemin between two loops, which harbor the axial ligands h32 and y75. hemin binding to the y75 loop triggers closing of the h32 loop and enables binding of h32. because yersinia pestis hasa (hasa(yp)) presents a gln at position 32, we determined the structures of apo- and holo-hasa(yp). surprisingly, the q32 loop in apo-hasa(yp) is already in the closed conformation, but no residue from the q32 loop binds hem ... | 2013 | 23578210 |
| the effect of 'candidatus liberibacter asiaticus' infection on the proteomic profiles and nutritional status of pre-symptomatic and symptomatic grapefruit (citrus paradisi) plants. | huanglongbing (hlb) is a highly destructive citrus disease which threatens citrus production worldwide and 'candidatus liberibacter asiaticus' (las), a non-culturable phloem-limited bacterium, is an associated causal agent of the disease. to better understand the physiological and molecular processes involved in host responses to las, 2-de and mass spectrometry analyses, as well as icp spectroscopy analysis were employed to elucidate the global protein expression profiles and nutrient concentrat ... | 2013 | 23578104 |
| effects of pesticides on the reduction of plant and human pathogenic bacteria in application water. | overhead spray applications of in-field tomato treatments dissolved in aqueous solutions have specific pest targets (fungal, bacterial, insect, or other). any organism present in the solution or on treated plant surfaces that is not a specific target of the application is unlikely inactivated and can instead be spread through the phyllosphere. in this laboratory study, commercially labeled pesticides (including actigard 50wg, bravo weather stik 6f, cabrio 20eg, kasumin, kocide 3000 46wg, oxidate ... | 2013 | 23575141 |
| re-annotation of protein-coding genes in 10 complete genomes of neisseriaceae family by combining similarity-based and composition-based methods. | in this paper, we performed a comprehensive re-annotation of protein-coding genes by a systematic method combining composition- and similarity-based approaches in 10 complete bacterial genomes of the family neisseriaceae. first, 418 hypothetical genes were predicted as non-coding using the composition-based method and 413 were eliminated from the gene list. both the scatter plot and cluster of orthologous groups (cog) fraction analyses supported the result. second, from 20 to 400 hypothetical pr ... | 2013 | 23571676 |
| draft genome of the mountain pine beetle, dendroctonus ponderosae hopkins, a major forest pest. | the mountain pine beetle, dendroctonus ponderosae hopkins, is the most serious insect pest of western north american pine forests. a recent outbreak destroyed more than 15 million hectares of pine forests, with major environmental effects on forest health, and economic effects on the forest industry. the outbreak has in part been driven by climate change, and will contribute to increased carbon emissions through decaying forests. | 2013 | 23537049 |
| crispr-cas systems preferentially target the leading regions of mobf conjugative plasmids. | most prokaryotes contain crispr-cas immune systems that provide protection against mobile genetic elements. we have focused on the ability of crispr-cas to block plasmid conjugation, and analyzed the position of target sequences (protospacers) on conjugative plasmids. the analysis reveals that protospacers are non-uniformly distributed over plasmid regions in a pattern that is determined by the plasmid's mobilization type (mob). while mobp plasmids are most frequently targeted in the region ente ... | 2013 | 23535265 |
| considerations for using bacteriophages for plant disease control. | the use of bacteriophages as an effective phage therapy strategy faces significant challenges for controlling plant diseases in the phyllosphere. a number of factors must be taken into account when considering phage therapy for bacterial plant pathogens. given that effective mitigation requires high populations of phage be present in close proximity to the pathogen at critical times in the disease cycle, the single biggest impediment that affects the efficacy of bacteriophages is their inability ... | 2012 | 23531902 |
| development of somatic hybrids solanum × michoacanum bitter. (rydb.) (+) s. tuberosum l. and autofused 4x s. × michoacanum plants as potential sources of late blight resistance for potato breeding. | phytophthora infestans resistant somatic hybrids of s. × michoacanum (+) s. tuberosum and autofused 4 x s. × michoacanum were obtained. our material is promising to introgress resistance from s. × michoacanum into cultivated potato background. solanum × michoacanum (bitter.) rydb. (mch) is a wild diploid (2n = 2x = 24) potato species derived from spontaneous cross of s. bulbocastanum and s. pinnatisectum. this hybrid is a 1 ebn (endosperm balance number) species and can cross effectively only wi ... | 2013 | 23525760 |
| whole-genome sequences of chlamydia trachomatis directly from clinical samples without culture. | the use of whole-genome sequencing as a tool for the study of infectious bacteria is of growing clinical interest. chlamydia trachomatis is responsible for sexually transmitted infections and the blinding disease trachoma, which affect hundreds of millions of people worldwide. recombination is widespread within the genome of c. trachomatis, thus whole-genome sequencing is necessary to understand the evolution, diversity, and epidemiology of this pathogen. culture of c. trachomatis has, until now ... | 2013 | 23525359 |
| acute lymphoblastic leukaemia. | acute lymphoblastic leukaemia occurs in both children and adults but its incidence peaks between 2 and 5 years of age. causation is multifactorial and exogenous or endogenous exposures, genetic susceptibility, and chance have roles. survival in paediatric acute lymphoblastic leukaemia has improved to roughly 90% in trials with risk stratification by biological features of leukaemic cells and response to treatment, treatment modification based on patients' pharmacodynamics and pharmacogenomics, a ... | 2013 | 23523389 |
| synthesis and structure-activity relationship of n-(cinnamyl) chitosan analogs as antimicrobial agents. | the current study focuses on the preparation of new n-(cinnamyl) chitosan derivatives as antimicrobial agents against nine types of crop-threatening pathogens. chitosan was reacted with a set of aromatic cinnamaldehyde analogs by reductive amination involving formation of the corresponding imines, followed by reduction with sodium borohydride to produce n-(cinnamyl) chitosan derivatives. the structural characterization was confirmed by (1)h and (13)c nmr spectroscopy and the degrees of substitut ... | 2013 | 23511055 |
| endosymbiotic bacteria in insects: guardians of the immune system? | insects have evolved obligate, mutualistic interactions with bacteria without further transmission to other eukaryotic organisms. such long-term obligate partnerships between insects and bacteria have a profound effect on various physiological functions of the host. here we provide an overview of the effects of endosymbiotic bacteria on the insect immune system as well as on the immune response of insects to pathogenic infections. potential mechanisms through which endosymbionts can affect the a ... | 2013 | 23508299 |
| dsba and mgrb regulate stea expression through the two-component system phoq/phop in salmonella enterica. | stea is a protein that can be translocated into host cells through the two virulence-related type iii secretion systems that are present in salmonella enterica. we used the t-pop system to carry out general screens for loci that exhibited activation or repression of a stea::lacz fusion. these screens identified the histidine kinase phoq and the response regulator phop as positive regulators of stea. transcription of this gene is σ70 dependent, and the promoter of stea contains a phop-binding sit ... | 2013 | 23504014 |
| bioactive flavanoids from glycosmis arborea. | glycosmis is a genus of evergreen glabrous shrub and distributed all over india. it possesses various medicinal properties and is used in indigenous medicine for cough, rheumatism, anemia, and jaundice. glycosmis arborea is a rich source of alkaloids, terpenoids, coumarins, as well as flavonoids. | 2013 | 23497605 |
| oligogalacturonides: plant damage-associated molecular patterns and regulators of growth and development. | oligogalacturonides (ogs) are oligomers of alpha-1,4-linked galacturonosyl residues released from plant cell walls upon partial degradation of homogalacturonan. ogs are able to elicit defense responses, including accumulation of reactive oxygen species and pathogenesis-related proteins, and protect plants against pathogen infections. recent studies demonstrated that ogs are perceived by wall-associated kinases and share signaling components with microbe-associated molecular patterns. for this re ... | 2013 | 23493833 |
| bioactivity of malva sylvestris l., a medicinal plant from iran. | malva sylvestris l. (malvaceae), an annual plant, has been already commonly used as a medicinal plant in iran. in the present work, we evaluate some bioactivities of the plant extracts. | 2011 | 23493458 |
| pharmacological effects of rosa damascena. | rosa damascena mill l., known as gole mohammadi in is one of the most important species of rosaceae family flowers. r. damascena is an ornamental plant and beside perfuming effect, several pharmacological properties including anti-hiv, antibacterial, antioxidant, antitussive, hypnotic, antidiabetic, and relaxant effect on tracheal chains have been reported for this plant. this article is a comprehensive review on pharmacological effects of r. damascena. online literature searches were performed ... | 2011 | 23493250 |
| crisprtarget: bioinformatic prediction and analysis of crrna targets. | the bacterial and archaeal crispr/cas adaptive immune system targets specific protospacer nucleotide sequences in invading organisms. this requires base pairing between processed crispr rna and the target protospacer. for type i and ii crispr/cas systems, protospacer adjacent motifs (pam) are essential for target recognition, and for type iii, mismatches in the flanking sequences are important in the antiviral response. in this study, we examine the properties of each class of crispr. we use thi ... | 2013 | 23492433 |
| the multifaceted roles of antibiotics and antibiotic resistance in nature. | antibiotics are chemotherapeutic agents, which have been a very powerful tool in the clinical management of bacterial diseases since the 1940s. however, benefits offered by these magic bullets have been substantially lost in subsequent days following the widespread emergence and dissemination of antibiotic-resistant strains. while it is obvious that excessive and imprudent use of antibiotics significantly contributes to the emergence of resistant strains, antibiotic resistance is also observed i ... | 2013 | 23487476 |
| endophytic actinomycetes: a novel source of potential acyl homoserine lactone degrading enzymes. | several gram-negative pathogenic bacteria employ n-acyl-l-homoserine lactone (hsl) quorum sensing (qs) system to control their virulence traits. degradation of acyl-hsl signal molecules by quorum quenching enzyme (qqe) results in a loss of pathogenicity in qs-dependent organisms. the qqe activity of actinomycetes in rhizospheric soil and inside plant tissue was explored in order to obtain novel strains with high hsl-degrading activity. among 344 rhizospheric and 132 endophytic isolates, 127 (36. ... | 2013 | 23484156 |
| improving escherichia coli fuco for furfural tolerance by saturation mutagenesis of individual amino acid positions. | furfural is an inhibitory side product formed during the depolymerization of hemicellulose with mineral acids. in escherichia coli, furfural tolerance can be increased by expressing the native fuco gene (encoding lactaldehyde oxidoreductase). this enzyme also catalyzes the nadh-dependent reduction of furfural to the less toxic alcohol. saturation mutagenesis was combined with growth-based selection to isolate a mutated form of fuco that confers increased furfural tolerance. the mutation responsi ... | 2013 | 23475621 |
| exploiting quorum sensing to confuse bacterial pathogens. | cell-cell communication, or quorum sensing, is a widespread phenomenon in bacteria that is used to coordinate gene expression among local populations. its use by bacterial pathogens to regulate genes that promote invasion, defense, and spread has been particularly well documented. with the ongoing emergence of antibiotic-resistant pathogens, there is a current need for development of alternative therapeutic strategies. an antivirulence approach by which quorum sensing is impeded has caught on as ... | 2013 | 23471618 |
| the folate precursor para-aminobenzoic acid elicits induced resistance against cucumber mosaic virus and xanthomonas axonopodis. | the use of vitamins including vitamin b1, b2 and k3 for the induction of systemic acquired resistance (sar) to protect crops against plant pathogens has been evaluated previously. the use of vitamins is beneficial because it is cost effective and safe for the environment. the use of folate precursors, including ortho-aminobenzoic acid, to induce sar against a soft-rot pathogen in tobacco has been reported previously. | 2013 | 23471007 |
| isolation and characterization of a bacteriocin-like substance produced by geobacillus toebii strain hbb-247. | a total of 201 thermophilic bacteria isolated from various thermal spring, mud and soil were tested for their antibacterial activity. among the mostly active isolates, geobacillus toebii hbb-247 was further examined. bacteriocin-like inhibitory substance (blis) produced by strain hbb-247 was found to be stable up to 60°c, sensitive to proteolytic enzymes and effective against enterococcus faecalis, listeria sp., e. avium, clostridium pasteurianum, cellulomonas fimi and some thermophilic strains ... | 2011 | 23448995 |
| isolation and characterization of a bacteriocin-like substance produced by geobacillus toebii strain hbb-247. | a total of 201 thermophilic bacteria isolated from various thermal spring, mud and soil were tested for their antibacterial activity. among the mostly active isolates, geobacillus toebii hbb-247 was further examined. bacteriocin-like inhibitory substance (blis) produced by strain hbb-247 was found to be stable up to 60°c, sensitive to proteolytic enzymes and effective against enterococcus faecalis, listeria sp., e. avium, clostridium pasteurianum, cellulomonas fimi and some thermophilic strains ... | 2011 | 23448995 |
| plant-bacterium interactions analyzed by proteomics. | the evolution of the plant immune response has resulted in a highly effective defense system that is able to resist potential attack by microbial pathogens. the primary immune response is referred to as pathogen associated molecular pattern (pamp) triggered immunity and has evolved to recognize common features of microbial pathogens. in response to the delivery of pathogen effector proteins, plants acquired r proteins to fight against pathogen attack. r-dependent defense response is important in ... | 2013 | 23424014 |
| salmonella enterica suppresses pectobacterium carotovorum subsp. carotovorum population and soft rot progression by acidifying the microaerophilic environment. | although enteric human pathogens are usually studied in the context of their animal hosts, a significant portion of their life cycle occurs on plants. plant disease alters the phyllosphere, leading to enhanced growth of human pathogens; however, the impact of human pathogens on phytopathogen biology and plant health is largely unknown. to characterize the interaction between human pathogens and phytobacterial pathogens in the phyllosphere, we examined the interactions between pectobacterium caro ... | 2013 | 23404399 |
| phosphate limitation induces the intergeneric inhibition of pseudomonas aeruginosa by serratia marcescens isolated from paper machines. | phosphate is an essential nutrient for heterotrophic bacteria, affecting bacterioplankton in aquatic ecosystems and bacteria in biofilms. however, the influence of phosphate limitation on bacterial competition and biofilm development in multispecies populations has received limited attention in existing studies. to address this issue, we isolated 13 adhesive bacteria from paper machine aggregates. intergeneric inhibition of pseudomonas aeruginosa ww5 by serratia marcescens ww4 was identified und ... | 2013 | 23398522 |
| activation of defense mechanisms against pathogens in mosses and flowering plants. | during evolution, plants have developed mechanisms to cope with and adapt to different types of stress, including microbial infection. once the stress is sensed, signaling pathways are activated, leading to the induced expression of genes with different roles in defense. mosses (bryophytes) are non-vascular plants that diverged from flowering plants more than 450 million years ago, allowing comparative studies of the evolution of defense-related genes and defensive metabolites produced after mic ... | 2013 | 23380962 |
| lack of rsma-mediated control results in constant hypervirulence, cell elongation, and hyperflagellation in pectobacterium wasabiae. | the posttranscriptional regulator rsma controls the production of plant cell wall degrading enzymes (pcwde) and cell motility in the pectobacterium genus of plant pathogens. in this study the physiological role of gene regulation by rsma is under investigation. disruption of rsma gene of the pectobacterium wasabiae strain, scc3193 resulted in 3-fold decrease in growth rate and increased virulence. the comparison of mrna levels of the rsma(-) mutant and wild-type using a genome-wide microarray sh ... | 2013 | 23372695 |
| the use of fluorescent reporter protein tagging to study the interaction between root-knot nematodes and soft rot enterobacteriaceae. | the study of plant parasitic nematodes such as meloidogyne spp. and their interactions with phytopathogenic bacteria remains underexplored. one of the challenges towards establishing such interactions is the dependence on symptom development as a measure of interaction. in this study, mcherry was employed as a reporter protein to investigate the interaction between the soft rot enterobacteriaceae (sre) pectobacterium carotovorum subsp. brasiliensis (pcb) and root-knot nematode (m. incognita). pe ... | 2013 | 23347004 |
| characterization of a novel metagenome-derived 6-phospho-β-glucosidase from black liquor sediment. | the enzyme 6-phospho-β-glucosidase is an important member of the glycoside hydrolase family 1 (gh1). however, its catalytic mechanisms, especially the key residues determining substrate specificity and affinity, are poorly understood. a metagenome-derived gene sequence, encoding a novel 6-phospho-β-glucosidase designated pbgl25-217, was isolated and characterized. the optimal conditions for enzymatic activity were 37°c and ph 7; ca(2+), mg(2+), and mn(2+) stabilized the activity of pbgl25-217, w ... | 2013 | 23335769 |
| scar/wave-mediated processing of engulfed apoptotic corpses is essential for effective macrophage migration in drosophila. | in vitro studies have shown that scar/wave activates the arp2/3 complex to generate actin filaments, which in many cell types are organised into lamellipodia that are thought to have an important role in cell migration. here we demonstrate that scar is utilised by drosophila macrophages to drive their developmental and inflammatory migrations and that it is regulated via the hem/kette/nap1-containing scar/wave complex. scar is also important in protecting against bacterial pathogens and in wound ... | 2013 | 23328632 |
| consequences of disrupting salmonella ai-2 signaling on interactions within soft rots. | within soft rots, salmonella spp. reach population densities 10- to 100-fold higher than within intact plants. the hypothesis that salmonella spp. exchange ai-2 signals with pectobacterium carotovorum to increase its competitive fitness was tested using mutants involved in ai-2 production (luxs) or perception (lsracdbf or lsrg). co-infections of a wild-type salmonella sp. and its ai-2 mutants (at ≈3 to 10(4)) were established in green or red tomato ('fl 47' or 'campari' for 3 or 5 days) as well ... | 2013 | 23324045 |