| a common toxin fold mediates microbial attack and plant defense. | many plant pathogens secrete toxins that enhance microbial virulence by killing host cells. usually, these toxins are produced by particular microbial taxa, such as bacteria or fungi. in contrast, many bacterial, fungal and oomycete species produce necrosis and ethylene-inducing peptide 1 (nep1)-like proteins (nlps) that trigger leaf necrosis and immunity-associated responses in various plants. we have determined the crystal structure of an nlp from the phytopathogenic oomycete pythium aphanider ... | 2009 | 19520828 |
| homologs of the small rna sgrs are broadly distributed in enteric bacteria but have diverged in size and sequence. | sugar phosphate stress in escherichia coli is sensed and managed by the transcriptional regulator sgrr and the small rna (srna) sgrs. sgrs is a dual function rna that performs base pairing-dependent regulation of mrna targets and encodes a small protein, sgrt. homologs of sgrr were analyzed for gene synteny and inter-homolog identity to identify those that are likely to be functionally analogous. these 22 sgrr homologs were used to manually locate adjacent srnas functionally analogous to sgrs. s ... | 2009 | 19531735 |
| slya, a marr family transcriptional regulator, is essential for virulence in dickeya dadantii 3937. | slya, a marr family transcriptional regulator, controls an assortment of biological functions in several animal-pathogenic bacteria. in order to elucidate the functions of slya in the phytopathogen dickeya dadantii (formerly erwinia chrysanthemi) 3937, a slya gene deletion mutant (denoted deltaslya) was constructed. the mutant exhibited increased sensitivity to sodium hypochlorite, the cationic antimicrobial peptide polymyxin b, and oxidative stress. the mutant showed reduced production of pecta ... | 2009 | 19542281 |
| bacterial ortholog of mammalian translocator protein (tspo) with virulence regulating activity. | the translocator protein (tspo), previously designated as peripheral-type benzodiazepine receptor, is a protein mainly located in the outer mitochondrial membrane of eukaryotic cells. tspo is implicated in major physiological functions and functionally associated with other proteins such as the voltage-dependent anionic channel, also designated as mitochondrial porin. surprisingly, a tspo-related protein was identified in the photosynthetic bacterium rhodobacter sphaeroides but it was initially ... | 2009 | 19564920 |
| the rna binding protein csra is a pleiotropic regulator of the locus of enterocyte effacement pathogenicity island of enteropathogenic escherichia coli. | the attaching and effacing (a/e) pathogen enteropathogenic escherichia coli (epec) forms characteristic actin-filled membranous protrusions upon infection of host cells termed pedestals. here we examine the role of the rna binding protein csra in the expression of virulence genes and proteins that are necessary for pedestal formation. the csra mutant was defective in forming actin pedestals on epithelial cells and in disrupting transepithelial resistance across polarized epithelial cells. consis ... | 2009 | 19581394 |
| identification of amino acid residues of the pheromone-binding domain of the transcription factor trar that are required for positive control. | genes required for replication and for conjugal transfer of the agrobacterium tumefaciens ti plasmid are regulated by the quorum sensing transcription factor trar, whose n-terminal domain binds to the pheromone 3-oxo-octanoylhomoserine lactone (oohl) and whose c-terminal domain binds to specific dna sequences called tra boxes. here, we constructed 117 mutants, altering 103 surface-exposed amino acid residues of the trar n-terminal domain. each mutant was tested for activation of the trai promote ... | 2009 | 19602141 |
| the gacs/gaca signal transduction system of pseudomonas aeruginosa acts exclusively through its control over the transcription of the rsmy and rsmz regulatory small rnas. | we report here the results of an analysis of the regulatory range of the gacs/gaca two-component system in pseudomonas aeruginosa. using microarrays, we identified a large number of genes that are regulated by the system, and detected a near complete overlap of these genes with those regulated by two small rnas (srnas), rsmy and rsmz, suggesting that the expression of all gaca-regulated genes is rsmy/z-dependent. using genome-wide dna-protein interaction analyses, we identified only two genomic ... | 2009 | 19602144 |
| characterization of homologs of the small rna sgrs reveals diversity in function. | sgrs is a small rna (srna) that requires the rna chaperone hfq for its function. sgrs is a unique dual-function srna with a base pairing function that regulates mrna targets and an mrna function that allows production of the 43-amino-acid protein sgrt. sgrs is expressed when non-metabolizable sugars accumulate intracellularly (glucose-phosphate stress) and is required to allow escherichia coli cells to recover from stress. in this study, homologs of sgrs were used to complement an e. coli sgrs m ... | 2009 | 19620214 |
| mutagenesis and functional characterization of the rna and protein components of the toxin abortive infection and toxin-antitoxin locus of erwinia. | bacteria are constantly challenged by bacteriophage (phage) infection and have developed multiple adaptive resistance mechanisms. these mechanisms include the abortive infection systems, which promote "altruistic suicide" of an infected cell, protecting the clonal population. a cryptic plasmid of erwinia carotovora subsp. atroseptica, peca1039, has been shown to encode an abortive infection system. this highly effective system is active across multiple genera of gram-negative bacteria and agains ... | 2009 | 19633081 |
| endophytic bacteria associated with growing shoot tips of banana (musa sp.) cv. grand naine and the affinity of endophytes to the host. | a cultivation-based assessment of endophytic bacteria present in deep-seated shoot tips of banana suckers was made with a view to generate information on the associated organisms, potential endophytic contaminants in tissue-cultured bananas and to assess if the endophytes shared a beneficial relationship with the host. plating the tissue homogenate from the central core of suckers showed colony growth on nutrient agar from just 75% and 42% of the 12 stocks during may and november, respectively ( ... | 2009 | 19633807 |
| a quorum-sensing antagonist targets both membrane-bound and cytoplasmic receptors and controls bacterial pathogenicity. | quorum sensing is a process of bacterial communication involving production and detection of secreted molecules called autoinducers. gram-negative bacteria use acyl-homoserine lactone (ahl) autoinducers, which are detected by one of two receptor types. first, cytoplasmic luxr-type receptors bind accumulated intracellular ahls. ahl-luxr complexes bind dna and alter gene expression. second, membrane-bound luxn-type receptors bind accumulated extracellular ahls. ahl-luxn complexes relay information ... | 2009 | 19647512 |
| ind-6, a highly divergent ind-type metallo-beta-lactamase from chryseobacterium indologenes strain 597 isolated in burkina faso. | the genus chryseobacterium and other genera belonging to the family flavobacteriaceae include organisms that can behave as human pathogens and are known to cause different kinds of infections. several species of flavobacteriaceae, including chryseobacterium indologenes, are naturally resistant to beta-lactam antibiotics (including carbapenems), due to the production of a resident metallo-beta-lactamase. although c. indologenes presently constitutes a limited clinical threat, the incidence of inf ... | 2009 | 19651915 |
| exploitation of a new flagellatropic phage of erwinia for positive selection of bacterial mutants attenuated in plant virulence: towards phage therapy. | to isolate and characterize novel bacteriophages for the phytopathogen, erwinia carotovora ssp. atroseptica (eca), and to isolate phage-resistant mutants attenuated in virulence. | 2010 | 19674185 |
| identification of a modular pathogenicity island that is widespread among urease-producing uropathogens and shares features with a diverse group of mobile elements. | pathogenicity islands (pais) are a specific group of genomic islands that contribute to genomic variability and virulence of bacterial pathogens. using a strain-specific comparative genomic hybridization array, we report the identification of a 94-kb pai, designated icepm1, that is common to proteus mirabilis, providencia stuartii, and morganella morganii. these organisms are highly prevalent etiologic agents of catheter-associated urinary tract infections (cauti), the most common hospital acqui ... | 2009 | 19687197 |
| ehrlichia chaffeensis infections in drosophila melanogaster. | ehrlichia chaffeensis is an obligate, intracellular bacterium, transmitted by the tick amblyomma americanum, and is the causative agent of human monocytic ehrlichiosis infections. we previously demonstrated that e. chaffeensis is capable of growing in drosophila s2 cells. therefore, we tested the hypothesis that e. chaffeensis can infect adult drosophila melanogaster. adult drosophila organisms were experimentally challenged with intra-abdominal injections of bacteria. ehrlichia-infected flies s ... | 2009 | 19687202 |
| tocopherol, carotene, phenolic contents and antibacterial properties of rose essential oil, hydrosol and absolute. | the antioxidant and antibacterial activities, and total phenolic contents of rosa damascena mill. flower extracts (absolute, essential oil and hydrosol) were investigated. the chemical compositions of these extracts were analysed by gc-ms. phenylethyl alcohol (78.38%) was found to be the main constituent of rose absolute, while citrenellol and geraniol were the major compounds (>55%) of rose essential oil and hydrosol. tocopherol and carotene levels were determined by high performance liquid chr ... | 2009 | 19688375 |
| microarray comparative genomic hybridisation analysis incorporating genomic organisation, and application to enterobacterial plant pathogens. | microarray comparative genomic hybridisation (acgh) provides an estimate of the relative abundance of genomic dna (gdna) taken from comparator and reference organisms by hybridisation to a microarray containing probes that represent sequences from the reference organism. the experimental method is used in a number of biological applications, including the detection of human chromosomal aberrations, and in comparative genomic analysis of bacterial strains, but optimisation of the analysis is desi ... | 2009 | 19696881 |
| the qsec adrenergic signaling cascade in enterohemorrhagic e. coli (ehec). | the ability to respond to stress is at the core of an organism's survival. the hormones epinephrine and norepinephrine play a central role in stress responses in mammals, which require the synchronized interaction of the whole neuroendocrine system. mammalian adrenergic receptors are g-coupled protein receptors (gpcrs); bacteria, however, sense these hormones through histidine sensor kinases (hks). hks autophosphorylate in response to signals and transfer this phosphate to response regulators (r ... | 2009 | 19696934 |
| identification of a conserved chromosomal region encoding klebsiella pneumoniae type 1 and type 3 fimbriae and assessment of the role of fimbriae in pathogenicity. | type 3 fimbriae are expressed by most clinical klebsiella pneumoniae isolates and mediate adhesion to host structures in vitro. however, the role of type 3 fimbriae in k. pneumoniae virulence has not been evaluated by use of in vivo infection models. in this study, the type 3 fimbrial gene cluster (mrk) of the clinical isolate c3091 is described in detail. the mrk gene cluster was revealed to be localized in close proximity to the type 1 fimbrial gene cluster. thus, a 20.4-kb fimbria-encoding re ... | 2009 | 19703972 |
| extracellular secretion of carocin s1 in pectobacterium carotovorum subsp. carotovorum occurs via the type iii secretion system integral to the bacterial flagellum. | pectobacterium carotovorum subsp. carotovorum is a phytopathogenic enterobacterium responsible for soft rot, a disease characterized by extensive maceration of the affected plant tissue. this species also produces two or more antibacterial substances called bacteriocins, which enhance its competitiveness against related rival species. however, the secretion mechanism for low-molecular-weight bacteriocin is still unknown. | 2009 | 19712460 |
| the crystal structure of the escherichia coli autoinducer-2 processing protein lsrf. | many bacteria produce and respond to the quorum sensing signal autoinducer-2 (ai-2). escherichia coli and salmonella typhimurium are among the species with the lsr operon, an operon containing ai-2 transport and processing genes that are up regulated in response to ai-2. one of the lsr proteins, lsrf, has been implicated in processing the phosphorylated form of ai-2. here, we present the structure of lsrf, unliganded and in complex with two phospho-ai-2 analogues, ribose-5-phosphate and ribulose ... | 2009 | 19714241 |
| [identification and characterization of non-cultivated forms of enterobacteria erwinia carotovora in continuously incubated cultures]. | to determine overall number as well as number of viable cells in continuously incubated cultures of e. carotovora by methods of confocal microscopy and quantitative pcr-analysis. | 2009 | 19715209 |
| proteomic profiling of l-cysteine induced selenite resistance in enterobacter sp. ysu. | enterobacter sp. ysu is resistant to several different heavy metal salts, including selenite. a previous study using m-9 minimal medium showed that when the selenite concentration was 100,000 times higher than the sulfate concentration, selenite entered escherichia coli cells using two pathways: a specific and a non-specific pathway. in the specific pathway, selenite entered the cells through a yet to be characterized channel dedicated for selenite. in the non-specific pathway, selenite entered ... | 2009 | 19715574 |
| degradation of pathogen quorum-sensing molecules by soil bacteria: a preventive and curative biological control mechanism. | abstract the plasmid pme6863, carrying the aiia gene from the soil bacterium bacillus sp. a24 that encodes a lactonase enzyme able to degrade n-acyl-homoserine lactones (ahls), was introduced into the rhizosphere isolate pseudomonas fluorescens p3. this strain is not an effective biological control agent against plant pathogens. the transformant p. fluorescens p3/pme6863 acquired the ability to degrade ahls. in planta, p. fluorescens p3/pme6863 significantly reduced potato soft rot caused by erw ... | 2003 | 19719608 |
| the dif/xer recombination systems in proteobacteria. | in e. coli, 10 to 15% of growing bacteria produce dimeric chromosomes during dna replication. these dimers are resolved by xerc and xerd, two tyrosine recombinases that target the 28-nucleotide motif (dif) associated with the chromosome's replication terminus. in streptococci and lactococci, an alternative system is composed of a unique, xer-like recombinase (xers) genetically linked to a dif-like motif (dif(sl)) located at the replication terminus. preliminary observations have suggested that t ... | 2009 | 19727445 |
| combining flow cytometry and gfp reporter gene for quantitative evaluation of pectpbacterium carotovorum ssp. carotovorum in ornithogalum dubium plantlets. | ornithogalum dubium is a natural host of the soft rot pathogen pectobacterium carotovorum ssp. carotovorum (pcc). the present study was aimed to develop a quantification system for pcc expressing a gfp reporter gene, using fluorescent activated cell sorter (facs) in planta. | 2010 | 19732215 |
| mutations that disrupt either the pqq or the gdh gene of rahnella aquatilis abolish the production of an antibacterial substance and result in reduced biological control of grapevine crown gall. | rahnella aquatilis hx2, a biocontrol agent for grapevine crown gall caused by agrobacterium vitis, produces an antibacterial substance that inhibits the growth of a. vitis in vitro. in this study, we show that mh15 and mh16, two tn5-induced mutants of hx2, have lost their abilities to inhibit a. vitis and have reduced biocontrol activities; they grow in logarithmic phase at a rate similar to that of the wild type and have single tn5 insertions. they are also impaired in producing pyrroloquinolin ... | 2009 | 19734331 |
| novel n-acylhomoserine lactone-degrading bacteria isolated from the leaf surface of solanum tuberosum and their quorum-quenching properties. | we isolated and identified ahl-degrading bacteria from the leaf surface of solanum tuberosum. the 16 isolates inactivated both short- and long-chain ahls. two of these isolates, identified as microbacterium testaceum, showed putative ahl-lactonase activity. these two strains interrupted quorum-sensing dependent bacterial infection by plant pathogen pectobacterium carotovorum subsp. carotovorum. m. testaceum strains, which were isolated in this study, might be useful in the biocontrol of plant di ... | 2009 | 19734660 |
| identification of novel bioactive hexapeptides against phytopathogenic bacteria through rapid screening of a synthetic combinatorial library. | antimicrobial peptides (amps) are considered to be a promising alternative to conventional antibiotics for future generations. we identified four novel hexapeptides with antimicrobial activity: kcm11 (twwrww-nh(2)), kcm12 (kwrwiw-nh(2)), kcm21 (kwwwrw-nh(2)), and krs22 (wrwfih-nh(2)), through positional scanning of a synthetic peptide combinatorial library (ps-scl). the ability of these peptides to inhibit the growth of a variety of bacteria and unicellular fungi was evaluated. kcm11 and krs22 p ... | 2009 | 19734717 |
| arabidopsis thaliana mitochondrial glyoxalase 2-1 exhibits beta-lactamase activity. | in an effort to determine the physiological role of arabidopsis thaliana glx2-1, we attempted to uncover a substrate for the enzyme. glx2-1 did not effectively process 192 diverse substrates found in a commercial screen used for microorganism identification or exhibit arylsulfatase, lactonase, or phosphotriesterase activities. however, glx2-1 does exhibit beta-lactamase activity with k(cat)/km values from 10(3) to 10(5) m(-1) s(-1). glx2-1 can hydrolyze cephalosporins and carbapenems, albeit wit ... | 2009 | 19735113 |
| structures of the arm-type binding domains of hpi and hai7 integrases. | the structures of the n-terminal domains of two integrases of closely related but not identical asn tdna-associated genomic islands, yersinia hpi (high pathogenicity island; encoding siderophore yersiniabactin biosynthesis and transport) and an erwinia carotovora genomic island with yet unknown function, hai7, have been resolved. both integrases utilize a novel four-stranded beta-sheet dna-binding motif, in contrast to the known proteins that bind their dna targets by means of three-stranded bet ... | 2009 | 19737930 |
| biological properties of the chilean native moss sphagnum magellanicum. | an ethanol extract prepared from the gametophyte chilean native moss sphagnum magellanicum was dried out, weighed and dissolved in distilled water. this extract was then assayed for its antibacterial activity against the g(-) bacteria azotobacter vinelandii, erwinia carotovora subsp. carotovora, enterobacter aerogenes, escherichia coli, pseudomonas aeruginosa, salmonella typhi, vibrio cholerae, and the g(+) bacteria staphylococcus aureus subsp. aureus, and streptococcus type beta. the growth of ... | 2009 | 19746269 |
| identification of functional lsrb-like autoinducer-2 receptors. | although a variety of bacterial species have been reported to use the interspecies communication signal autoinducer-2 (ai-2) to regulate multiple behaviors, the molecular mechanisms of ai-2 recognition and signal transduction remain poorly understood. to date, two types of ai-2 receptors have been identified: luxp, present in vibrio spp., and lsrb, first identified in salmonella enterica serovar typhimurium. in s. typhimurium, lsrb is the ligand binding protein of a transport system that enables ... | 2009 | 19749048 |
| expression of bacterial genes in transgenic tobacco: methods, applications and future prospects. | tobacco is the most commonly used plant for expression of transgenes from a variety of organisms, because it is easily grown and transformed, it provides abundant amounts of fresh tissue and has a well-established cell culture system. many bacterial proteins involved in the synthesis of commercial products are currently engineered for production in tobacco. bacterial enzymes synthesized in tobacco can enhance protection against abiotic stresses and diseases, and provide a system to test applied ... | 2007 | 19750137 |
| zinc-independent folate biosynthesis: genetic, biochemical, and structural investigations reveal new metal dependence for gtp cyclohydrolase ib. | gtp cyclohydrolase i (gcyh-i) is an essential zn(2+)-dependent enzyme that catalyzes the first step of the de novo folate biosynthetic pathway in bacteria and plants, the 7-deazapurine biosynthetic pathway in bacteria and archaea, and the biopterin pathway in mammals. we recently reported the discovery of a new prokaryotic-specific gcyh-i (gcyh-ib) that displays no sequence identity to the canonical enzyme and is present in approximately 25% of bacteria, the majority of which lack the canonical ... | 2009 | 19767425 |
| the dlt operon of bacillus cereus is required for resistance to cationic antimicrobial peptides and for virulence in insects. | the dlt operon encodes proteins that alanylate teichoic acids, the major components of cell walls of gram-positive bacteria. this generates a net positive charge on bacterial cell walls, repulsing positively charged molecules and conferring resistance to animal and human cationic antimicrobial peptides (amps) in gram-positive pathogenic bacteria. amps damage the bacterial membrane and are the most effective components of the humoral immune response against bacteria. we investigated the role of t ... | 2009 | 19767427 |
| [use of the gene of antimicrobial peptide cecropin p1 for producing marker-free transgenic plants]. | the marker-free transgenic tobacco plants carrying a synthetic gene encoding the antimicrobial peptide cecropin p1 (cecp1) under the control of the cauliflower mosaic virus 35s rna promoter were produced. the binary vector pbm, free of any selective genes of resistance to antibiotics or herbicides intended for selecting transgenic plants, was used for transformation. the transformants were screened on a nonselective medium by detecting cecropin p1 in plant cells according to the antibacterial ac ... | 2009 | 19769295 |
| bioactive and structural metabolites of pseudomonas and burkholderia species causal agents of cultivated mushrooms diseases. | pseudomonas tolaasii, p. reactans and burkholderia gladioli pv. agaricicola, are responsible of diseases on some species of cultivated mushrooms. the main bioactive metabolites produced by both pseudomonas strains are the lipodepsipeptides (ldps) tolaasin i and ii and the so called white line inducing principle (wlip), respectively, ldps which have been extensively studied for their role in the disease process and for their biological properties. in particular, their antimicrobial activity and t ... | 2008 | 19787100 |
| effect of the o-antigen length of lipopolysaccharide on the functions of type iii secretion systems in salmonella enterica. | the virulence of salmonella enterica critically depends on the functions of two type iii secretion systems (t3ss), with the salmonella pathogenicity island 1 (spi1)-encoded t3ss required for host cell invasion and the spi2-t3ss enabling salmonella to proliferate within host cells. a further t3ss is required for the assembly of the flagella. most serovars of salmonella also possess a lipopolysaccharide with a complex o-antigen (oag) structure. the number of oag units attached to the core polysacc ... | 2009 | 19797066 |
| immune activation by life-shortening wolbachia and reduced filarial competence in mosquitoes. | wolbachia strain wmelpop reduces the longevity of its drosophila melanogaster host and, when introduced into the mosquito aedes aegypti, halves its life span. we show that wmelpop induces up-regulation of the mosquito's innate immune system and that its presence inhibits the development of filarial nematodes in the mosquito. these data suggest that wmelpop could be used in the global effort to eliminate lymphatic filariasis and possibly for the control of other mosquito-borne parasites where imm ... | 2009 | 19797660 |
| invasive and indigenous microbiota impact intestinal stem cell activity through multiple pathways in drosophila. | gut homeostasis is controlled by both immune and developmental mechanisms, and its disruption can lead to inflammatory disorders or cancerous lesions of the intestine. while the impact of bacteria on the mucosal immune system is beginning to be precisely understood, little is known about the effects of bacteria on gut epithelium renewal. here, we addressed how both infectious and indigenous bacteria modulate stem cell activity in drosophila. we show that the increased epithelium renewal observed ... | 2009 | 19797770 |
| legionella pneumophila secretes an endoglucanase that belongs to the family-5 of glycosyl hydrolases and is dependent upon type ii secretion. | examination of cell-free culture supernatants revealed that legionella pneumophila strains secrete an endoglucanase activity. legionella pneumophila lspf mutants were deficient for this activity, indicating that the endoglucanase is secreted by the bacterium's type ii protein secretion (t2s) system. inactivation of cela, encoding a member of the family-5 of glycosyl hydrolases, abolished the endoglucanase activity in l. pneumophila culture supernatants. the cloned cela gene conferred activity up ... | 2009 | 19817866 |
| kunitz trypsin inhibitor: an antagonist of cell death triggered by phytopathogens and fumonisin b1 in arabidopsis. | programmed cell death (pcd) is a central regulatory process in both plant development and in plant responses to pathogens. pcd requires a coordinate activation of pro-apoptotic factors such as proteases and suppressors inhibiting and modulating these processes. in plants, various caspase-like cysteine proteases as well as serine proteases have been implicated in pcd. here, we show that a serine protease (kunitz trypsin) inhibitor (kti1) of arabidopsis acts as a functional kti when produced in ba ... | 2008 | 19825555 |
| drosophila translational elongation factor-1gamma is modified in response to doa kinase activity and is essential for cellular viability. | drosophila translational elongation factor-1gamma (ef1gamma) interacts in the yeast two-hybrid system with doa, the lammer protein kinase of drosophila. analysis of mutant ef1gamma alleles reveals that the locus encodes a structurally conserved protein essential for both organismal and cellular survival. although no genetic interactions were detected in combinations with mutations in ef1alpha, an ef1gamma allele enhanced mutant phenotypes of doa alleles. a predicted lammer kinase phosphorylation ... | 2010 | 19841092 |
| genome sequence of the versatile fish pathogen edwardsiella tarda provides insights into its adaptation to broad host ranges and intracellular niches. | edwardsiella tarda is the etiologic agent of edwardsiellosis, a devastating fish disease prevailing in worldwide aquaculture industries. here we describe the complete genome of e. tarda, eib202, a highly virulent and multi-drug resistant isolate in china. | 2009 | 19865481 |
| a type vi secretion system effector protein, vgrg1, from aeromonas hydrophila that induces host cell toxicity by adp ribosylation of actin. | we recently delineated the importance of a type vi secretion system (t6ss) gene cluster in the virulence of diarrheal isolate ssu of aeromonas hydrophila and showed that vash, a sigma(54) activator and t6ss component, was involved in the production of its associated effectors, e.g., hemolysin-coregulated protein. to identify additional t6ss effectors and/or secreted proteins, we subjected culture supernatants from deletion mutants of a. hydrophila, namely, a delta act mutant (a t2ss-associated c ... | 2010 | 19880608 |
| a type vi secretion system effector protein, vgrg1, from aeromonas hydrophila that induces host cell toxicity by adp ribosylation of actin. | we recently delineated the importance of a type vi secretion system (t6ss) gene cluster in the virulence of diarrheal isolate ssu of aeromonas hydrophila and showed that vash, a sigma(54) activator and t6ss component, was involved in the production of its associated effectors, e.g., hemolysin-coregulated protein. to identify additional t6ss effectors and/or secreted proteins, we subjected culture supernatants from deletion mutants of a. hydrophila, namely, a delta act mutant (a t2ss-associated c ... | 2010 | 19880608 |
| novel low-temperature-active phytase from erwinia carotovora var.carotovota accc 10276. | a phytase with high activity at low temperatures has great potential for feed applications, especially in aquaculture. therefore, this study used a degenerate pcr and tail pcr to clone a phytase gene from erwinia carotovora var. carotovota, the cause of soft rot of vegetables in the ground or during cold storage. the full-length 2.5-kb fragment included an open reading frame of 1,302 bp and encoded a putative phytase of 45.3 kda with a 50% amino acid identity to the klebsiella pneumoniae phytase ... | 2009 | 19884763 |
| transgenic amorphophallus konjac expressing synthesized acyl-homoserine lactonase (aiia) gene exhibit enhanced resistance to soft rot disease. | amorphophallus konjac is an important economic crop widely used in health products and biomaterials. however, this monocotyledonous plant's production is seriously restricted by soft rot disease. some bacillus thuringiensis strains generate an endocellular acyl homoserine lactonase (aiia), which has inhibitory effect on soft rot pathogen through disrupting the signal molecules (n-acylhomoserine lactones, ahl) of their quorum sensing system. the aim of our study is to obtain transgenic a. konjac ... | 2009 | 19898849 |
| the effects of extracellular adenosine 5'-triphosphate on the tobacco proteome. | extracellular adenosine 5'-triphosphate (eatp) is emerging as an important plant signalling compound capable of mobilising intracellular second messengers such as ca(2+), nitric oxide, and reactive oxygen species. however, the downstream molecular targets and the spectrum of physiological processes that eatp regulates are largely unknown. we used exogenous atp and a non-hydrolysable analogue as probes to identify the molecular and physiological effects of eatp-mediated signalling in tobacco. 2-d ... | 2010 | 19899079 |
| a virus-induced gene silencing screen identifies a role for thylakoid formation1 in pseudomonas syringae pv tomato symptom development in tomato and arabidopsis. | pseudomonas syringae pv tomato dc3000 (pst dc3000), which causes disease in tomato (solanum lycopersicum) and arabidopsis (arabidopsis thaliana), produces coronatine (cor), a non-host-specific phytotoxin. cor, which functions as a jasmonate mimic, is required for full virulence of pst dc3000 and for the induction of chlorosis in host plants. previous genetic screens based on insensitivity to cor and/or methyl jasmonate identified several potential targets for cor and methyl jasmonate. in this st ... | 2010 | 19915014 |
| identification and characterization of the metal ion-dependent l-alanoyl-d-glutamate peptidase encoded by bacteriophage t5. | although bacteriophage t5 is known to have lytic proteins for cell wall hydrolysis and phage progeny escape, their activities are still unknown. this is the first report on the cloning, expression and biochemical characterization of a bacteriophage t5 lytic hydrolase. the endolysin-encoding lys gene of virulent coliphage t5 was cloned in escherichia coli cells, and an electrophoretically homogeneous product of this gene was obtained with a high yield (78% of total activity). the protein purified ... | 2009 | 19919545 |
| synergy between bacterial infection and genetic predisposition in intestinal dysplasia. | accumulating evidence suggests that hyperproliferating intestinal stem cells (scs) and progenitors drive cancer initiation, maintenance, and metastasis. in addition, chronic inflammation and infection have been increasingly recognized for their roles in cancer. nevertheless, the mechanisms by which bacterial infections can initiate sc-mediated tumorigenesis remain elusive. using a drosophila model of gut pathogenesis, we show that intestinal infection with pseudomonas aeruginosa, a human opportu ... | 2009 | 19934041 |
| toll-dependent antimicrobial responses in drosophila larval fat body require spätzle secreted by haemocytes. | in drosophila, the humoral response characterised by the synthesis of antimicrobial peptides (amps) in the fat body (the equivalent of the mammalian liver) and the cellular response mediated by haemocytes (blood cells) engaged in phagocytosis represent two major reactions that counter pathogens. although considerable analysis has permitted the elucidation of mechanisms pertaining to the two responses individually, the mechanism of their coordination has been unclear. to characterise the signals ... | 2009 | 19934223 |
| enterobacterial small mobile sequences carry open reading frames and are found intragenically--evolutionary implications for formation of new peptides. | intergenic repeat units of 127-bp (ru-1) and 168-bp (ru-2), as well as a newly-found class of 103-bp (ru-3), represent small mobile sequences in enterobacterial genomes present in multiple intergenic regions. these repeat sequences display similarities to eukaryotic miniature inverted-repeat transposable elements (mite). the ru mobile elements have not been reported to encode amino acid sequences. an in silico approach was used to scan genomes for location of repeat units. ru sequences are found ... | 2007 | 19936088 |
| [the characteristic of the colispecific bacteriocins of erwinia carotovora subsp. carotovora ec153]. | it has been shown for the first time that macromolecular carotovoricins from erwinia carotovora subsp. carotovora ec153 strain are active to escherichia coli and posses endonuclease activity. it has been established that 19.1% of strains isolated from the patients are sensitive to these bacteriocins. the type and the form of these particles have been also determined and they show resemblance with phage objects. | 2009 | 19938602 |
| [phytopathogenic bacteria of couch-grass in the crops of wheat]. | bacterialdiseases of weeds in the crops of wheat on the fields of kyiv and vinnytsya regions of ukraine elytrigia repens (l.) nevski agropyrum repens l. were revealed. the following symptoms of bacterial affections: the leaves wither, oval or hatched necrotic spots on green leaves, necroses on the stalks, empty-ears, partial blackening of the ear axes, awns, caryopsises, scales, water-soaked or dark brown with violet shade spots on the rhizomes were found. during the vegetation period bacteria w ... | 2009 | 19938603 |
| role of rpos in virulence of pathogens. | understanding mechanisms of bacterial pathogenesis is critical for infectious disease control and treatment. infection is a sophisticated process that requires the participation of global regulators to coordinate expression of not only genes coding for virulence factors but also those involved in other physiological processes, such as stress response and metabolic flux, to adapt to host environments. rpos is a key response regulator to stress conditions in escherichia coli and many other proteob ... | 2010 | 19948835 |
| role of rpos in virulence of pathogens. | understanding mechanisms of bacterial pathogenesis is critical for infectious disease control and treatment. infection is a sophisticated process that requires the participation of global regulators to coordinate expression of not only genes coding for virulence factors but also those involved in other physiological processes, such as stress response and metabolic flux, to adapt to host environments. rpos is a key response regulator to stress conditions in escherichia coli and many other proteob ... | 2010 | 19948835 |
| inhibition by chestnut honey of n-acyl-l-homoserine lactones and biofilm formation in erwinia carotovora, yersinia enterocolitica, and aeromonas hydrophila. | bacteria are able to communicate and coordinate certain processes using small secreted signaling molecules called autoinducers. this phenomenon, known as "quorum sensing" (qs), may be essential for the synchronization of virulence factors as well as biofilm development. the interruption of bacterial qs is acknowledged to attenuate virulence and considered to be a potential new therapy to treat infections caused by pathogenic bacteria. n-acyl-l-homoserine lactones (ahls) have been identified as t ... | 2009 | 19950997 |
| genetic and phenotypic diversity of ralstonia solanacearum biovar 2 strains obtained from dutch waterways. | a novel set of ralstonia solanacearum biovar 2 isolates was obtained, at several sampling occasions, from dutch waterways, sediment and bittersweet plants and their genetic and phenotypic diversity was investigated. as reference strains, two previously-described strains obtained from diseased potato plants, denoted 1609 (the netherlands) and 715 (bangladesh), were included in the analyses. all novel isolates showed box and gtg5 pcr based genomic profiles similar to those of the reference strains ... | 2010 | 19960250 |
| genetic and phenotypic diversity of ralstonia solanacearum biovar 2 strains obtained from dutch waterways. | a novel set of ralstonia solanacearum biovar 2 isolates was obtained, at several sampling occasions, from dutch waterways, sediment and bittersweet plants and their genetic and phenotypic diversity was investigated. as reference strains, two previously-described strains obtained from diseased potato plants, denoted 1609 (the netherlands) and 715 (bangladesh), were included in the analyses. all novel isolates showed box and gtg5 pcr based genomic profiles similar to those of the reference strains ... | 2010 | 19960250 |
| expression of a synthesized gene encoding cationic peptide cecropin b in transgenic tomato plants protects against bacterial diseases. | the cationic lytic peptide cecropin b (cb), isolated from the giant silk moth (hyalophora cecropia), has been shown to effectively eliminate gram-negative and some gram-positive bacteria. in this study, the effects of chemically synthesized cb on plant pathogens were investigated. the s(50)s (the peptide concentrations causing 50% survival of a pathogenic bacterium) of cb against two major pathogens of the tomato, ralstonia solanacearum and xanthomonas campestris pv. vesicatoria, were 529.6 micr ... | 2010 | 19966019 |
| expression of a synthesized gene encoding cationic peptide cecropin b in transgenic tomato plants protects against bacterial diseases. | the cationic lytic peptide cecropin b (cb), isolated from the giant silk moth (hyalophora cecropia), has been shown to effectively eliminate gram-negative and some gram-positive bacteria. in this study, the effects of chemically synthesized cb on plant pathogens were investigated. the s(50)s (the peptide concentrations causing 50% survival of a pathogenic bacterium) of cb against two major pathogens of the tomato, ralstonia solanacearum and xanthomonas campestris pv. vesicatoria, were 529.6 micr ... | 2010 | 19966019 |
| diversity and evolution of the phenazine biosynthesis pathway. | phenazines are versatile secondary metabolites of bacterial origin that function in biological control of plant pathogens and contribute to the ecological fitness and pathogenicity of the producing strains. in this study, we employed a collection of 94 strains having various geographic, environmental, and clinical origins to study the distribution and evolution of phenazine genes in members of the genera pseudomonas, burkholderia, pectobacterium, brevibacterium, and streptomyces. our results con ... | 2010 | 20008172 |
| diversity and evolution of the phenazine biosynthesis pathway. | phenazines are versatile secondary metabolites of bacterial origin that function in biological control of plant pathogens and contribute to the ecological fitness and pathogenicity of the producing strains. in this study, we employed a collection of 94 strains having various geographic, environmental, and clinical origins to study the distribution and evolution of phenazine genes in members of the genera pseudomonas, burkholderia, pectobacterium, brevibacterium, and streptomyces. our results con ... | 2010 | 20008172 |
| lysogeny and sporulation in bacillus isolates from the gulf of mexico. | eleven bacillus isolates from the surface and subsurface waters of the gulf of mexico were examined for their capacity to sporulate and harbor prophages. occurrence of sporulation in each isolate was assessed through decoyinine induction, and putative lysogens were identified by prophage induction by mitomycin c treatment. no obvious correlation between ability to sporulate and prophage induction was found. four strains that contained inducible virus-like particles (vlps) were shown to sporulate ... | 2010 | 20008174 |
| lysogeny and sporulation in bacillus isolates from the gulf of mexico. | eleven bacillus isolates from the surface and subsurface waters of the gulf of mexico were examined for their capacity to sporulate and harbor prophages. occurrence of sporulation in each isolate was assessed through decoyinine induction, and putative lysogens were identified by prophage induction by mitomycin c treatment. no obvious correlation between ability to sporulate and prophage induction was found. four strains that contained inducible virus-like particles (vlps) were shown to sporulate ... | 2010 | 20008174 |
| plant defensins: defense, development and application. | plant defensins are small, highly stable, cysteine-rich peptides that constitute a part of the innate immune system primarily directed against fungal pathogens. biological activities reported for plant defensins include antifungal activity, antibacterial activity, proteinase inhibitory activity and insect amylase inhibitory activity. plant defensins have been shown to inhibit infectious diseases of humans and to induce apoptosis in a human pathogen. transgenic plants overexpressing defensins are ... | 2009 | 20009545 |
| one nutritional symbiosis begat another: phylogenetic evidence that the ant tribe camponotini acquired blochmannia by tending sap-feeding insects. | bacterial endosymbiosis has a recurring significance in the evolution of insects. an estimated 10-20% of insect species depend on bacterial associates for their nutrition and reproductive viability. members of the ant tribe camponotini, the focus of this study, possess a stable, intracellular bacterial mutualist. the bacterium, blochmannia, was first discovered in camponotus and has since been documented in a distinct subgenus of camponotus, colobopsis, and in the related genus polyrhachis. howe ... | 2009 | 20015388 |
| non-heme iron oxygenases generate natural structural diversity in carbapenem antibiotics. | carbapenems are a clinically important antibiotic family. more than 50 naturally occurring carbapenam/ems are known and are distinguished primarily by their c-2/c-6 side chains where many are only differentiated by the oxidation states of these substituents. with a limited palette of variations the carbapenem family comprises a natural combinatorial library, and c-2/c-6 oxidation is associated with increased efficacy. we demonstrate that thng and thnq encoded by the thienamycin gene cluster in s ... | 2010 | 20017478 |
| long-range activation of systemic immunity through peptidoglycan diffusion in drosophila. | the systemic immune response of drosophila is known to be induced both by septic injury and by oral infection with certain bacteria, and is characterized by the secretion of antimicrobial peptides (amps) into the haemolymph. to investigate other possible routes of bacterial infection, we deposited erwinia carotovora (ecc15) on various sites of the cuticle and monitored the immune response via expression of the amp gene diptericin. a strong response was observed to deposition on the genital plate ... | 2009 | 20019799 |
| interactions at the 2 and 5 positions of 5-phosphoribosyl pyrophosphate are essential in salmonella typhimurium quinolinate phosphoribosyltransferase. | quinolinate phosphoribosyltransferase (qaprtase, ec 2.4.2.19) catalyzes an unusual phosphoribosyl transfer that is linked to a decarboxylation reaction to form the nad precursor nicotinate mononucleotide, carbon dioxide, and pyrophosphate from quinolinic acid (qa) and 5-phosphoribosyl 1-pyrophosphate (prpp). structural studies and sequence similarities with other prtases have implicated glu214, asp235, lys153, and lys284 in contributing to catalysis through direct interaction with prpp. the four ... | 2010 | 20047307 |
| complete genome sequence of the fire blight pathogen erwinia pyrifoliae dsm 12163t and comparative genomic insights into plant pathogenicity. | erwinia pyrifoliae is a newly described necrotrophic pathogen, which causes fire blight on asian (nashi) pear and is geographically restricted to eastern asia. relatively little is known about its genetics compared to the closely related main fire blight pathogen e. amylovora. | 2010 | 20047678 |
| crystal structure of salt-tolerant glutaminase from micrococcus luteus k-3 in the presence and absence of its product l-glutamate and its activator tris. | glutaminase from micrococcus luteus k-3 [micrococcus glutaminase (mglu); 456 amino acid residues (aa); 48 kda] is a salt-tolerant enzyme. our previous study determined the structure of its major 42-kda fragment. here, using new crystallization conditions, we determined the structures of the intact enzyme in the presence and absence of its product l-glutamate and its activator tris, which activates the enzyme by sixfold. with the exception of a 'lid' part (26-29 aa) and a few other short stretche ... | 2010 | 20050917 |
| genetically pyramiding protease-inhibitor genes for dual broad-spectrum resistance against insect and phytopathogens in transgenic tobacco. | protease inhibitors provide a promising means of engineering plant resistance against attack by insects and pathogens. sporamin (trypsin inhibitor) from sweet potato and cecpi (phytocystatin) from taro were stacked in a binary vector, using pmspoa (a modified sporamin promoter) to drive both genes. transgenic tobacco lines of t0 and t1 generation with varied inhibitory activity against trypsin and papain showed resistance to both insects and phytopathogens. larvae of helicoverpa armigera that in ... | 2010 | 20055959 |
| mutations in rpsl that confer streptomycin resistance show pleiotropic effects on virulence and the production of a carbapenem antibiotic in erwinia carotovora. | spontaneous streptomycin-resistant derivatives of erwinia carotovora subsp. carotovora strain attn10 were isolated. sequencing of the rpsl locus (encoding the ribosomal protein s12) showed that each mutant was missense, with a single base change, resulting in the substitution of the wild-type lysine by arginine, threonine or asparagine at codon 43. phenotypic analyses showed that the rpsl mutants could be segregated into two groups: k43r mutants showed reduced production of the beta-lactam secon ... | 2010 | 20056700 |
| arabidopsis thaliana cells: a model to evaluate the virulence of pectobacterium carotovorum. | pectobacterium carotovorum are economically important plant pathogens that cause plant soft rot. these enterobacteria display high diversity world-wide. their pathogenesis depends on production and secretion of virulence factors such as plant cell wall-degrading enzymes, type iii effectors, a necrosis-inducing protein, and a secreted virulence factor from xanthomonas spp., which are tightly regulated by quorum sensing. pectobacterium carotovorum also present pathogen-associated molecular pattern ... | 2010 | 20064057 |
| rab35 mediates transport of cdc42 and rac1 to the plasma membrane during phagocytosis. | phagocytosis of invading microbes requires dynamic rearrangement of the plasma membrane and its associated cytoskeletal actin network. the polarization of cdc42 and rac1 rho gtpases to the site of plasma membrane protrusion is responsible for the remodeling of actin structures. however, the mechanism of rho gtpase recruitment to these sites and the identities of accessory molecules involved in this process are not well understood. in this study, we uncovered several new components involved in in ... | 2010 | 20065041 |
| [the influence of colonizing methylobacteria on morphogenesis and resistance of sugar beet and white cabbage plants to erwinia carotovora]. | the influence of colonization of sugar beet (beta vulgaris var. saccharifera (alef) krass) and white cabbage (brassica oleracea var. capitata l.) plants by methylotrophic bacteria methylovorus mays on the growth, rooting, and plant resistance to phytopathogen bacteria erwinia carotovora was investigated. the colonization by methylobacteria led to their steady association with the plants which had increased growth speed, root formation and photosynthetic activity. the colonized plants had increas ... | 2009 | 20067151 |
| reprogramming of anaerobic metabolism by the fnrs small rna. | small rnas (srnas) that act by base pairing with trans-encoded mrnas modulate metabolism in response to a variety of environmental stimuli. here, we describe an hfq-binding srna (fnrs) whose expression is induced upon a shift from aerobic to anaerobic conditions and which acts to downregulate the levels of a variety of mrnas encoding metabolic enzymes. anaerobic induction in minimal medium depends strongly on fnr but is also affected by the arca and crp transcription regulators. whole genome exp ... | 2010 | 20070527 |
| chloroplast-derived enzyme cocktails hydrolyse lignocellulosic biomass and release fermentable sugars. | it is widely recognized that biofuel production from lignocellulosic materials is limited by inadequate technology to efficiently and economically release fermentable sugars from the complex multi-polymeric raw materials. therefore, endoglucanases, exoglucanase, pectate lyases, cutinase, swollenin, xylanase, acetyl xylan esterase, beta glucosidase and lipase genes from bacteria or fungi were expressed in escherichia coli or tobacco chloroplasts. a pcr-based method was used to clone genes without ... | 2010 | 20070870 |
| salmonella regulation of intestinal stem cells through the wnt/beta-catenin pathway. | recent studies have revealed that bacteria target stem cells for long-term survival in a drosophila model. however, in mammalian models, little is known about bacterial infection and intestinal stem cells. our study aims at understanding bacterial regulation of the intestinal stem cell in a salmonella colitis mouse model. we found that salmonella activates the wnt/beta-catenin signaling pathway that is known to regulate stem cells. we identified salmonella protein avra that modulates wnt signali ... | 2010 | 20083111 |
| analysis of hmsh and its role in plague biofilm formation. | the yersinia pestis hms(+) phenotype is a manifestation of biofilm formation that causes adsorption of congo red and haemin at 26 degrees c but not at 37 degrees c. this phenotype is required for blockage of the proventricular valve of the oriental rat flea and plays a role in transmission of bubonic plague from fleas to mammals. genes responsible for this phenotype are located in three separate operons, hmshfrs, hmst and hmsp. hmsh and hmsf are outer membrane (om) proteins, while the other four ... | 2010 | 20093287 |
| specificity of the type ii secretion systems of enterotoxigenic escherichia coli and vibrio cholerae for heat-labile enterotoxin and cholera toxin. | the gram-negative type ii secretion (t2s) system is a multiprotein complex mediating the release of virulence factors from a number of pathogens. while an understanding of the function of t2s components is emerging, little is known about what identifies substrates for export. to investigate t2s substrate recognition, we compared mutations affecting the secretion of two highly homologous substrates: heat-labile enterotoxin (lt) from enterotoxigenic escherichia coli (etec) and cholera toxin (ct) f ... | 2010 | 20097854 |
| a role for the rcs phosphorelay in regulating expression of plant cell wall degrading enzymes in pectobacterium carotovorum subsp. carotovorum. | the rcs phosphorelay is a signal transduction system that influences the virulence phenotype of several pathogenic bacteria. in the plant pathogen pectobacterium carotovorum subsp. carotovorum (pcc) the response regulator of the rcs phosphorelay, rcsb, represses expression of plant cell wall degrading enzymes (pcwde) and motility. the focus of this study was to identify genes directly regulated by the binding of rcsb that also regulate expression of pcwde genes in pcc. rcsb-binding sites within ... | 2010 | 20110299 |
| salmonella sdia recognizes n-acyl homoserine lactone signals from pectobacterium carotovorum in vitro, but not in a bacterial soft rot. | genomes of salmonella enterica isolates, including those linked to outbreaks of produce-associated gastroenteritis, contain sdia, which encodes a receptor of n-acyl homoserine lactones (ahl). ahl are the quorum-sensing signals used by bacteria to coordinately regulate gene expression within -their populations. because s. enterica does not produce its own ahl, sdia is hypothesized to function in the interspecies cross-talk with ahl-producing bacteria. under laboratory conditions, s. enterica resp ... | 2010 | 20121449 |
| abundance of type i toxin-antitoxin systems in bacteria: searches for new candidates and discovery of novel families. | small, hydrophobic proteins whose synthesis is repressed by small rnas (srnas), denoted type i toxin-antitoxin modules, were first discovered on plasmids where they regulate plasmid stability, but were subsequently found on a few bacterial chromosomes. we used exhaustive psi-blast and tblastn searches across 774 bacterial genomes to identify homologs of known type i toxins. these searches substantially expanded the collection of predicted type i toxins, revealed homology of the ldr and fst toxin ... | 2010 | 20156992 |
| increased incidence of rare codon clusters at 5' and 3' gene termini: implications for function. | the process of translation can be affected by the use of rare versus common codons within the mrna transcript. | 2010 | 20167116 |
| aiim, a novel class of n-acylhomoserine lactonase from the leaf-associated bacterium microbacterium testaceum. | n-acylhomoserine lactones (ahls) are used as quorum-sensing signal molecules by many gram-negative bacteria. we have reported that microbacterium testaceum stlb037, which was isolated from the leaf surface of potato, has ahl-degrading activity. in this study, we cloned the aiim gene from the genomic library of stlb037, which has ahl-degrading activity and shows high homology with the alpha/beta hydrolase fold family from actinobacteria. purified aiim as a maltose binding fusion protein showed hi ... | 2010 | 20173075 |
| carbon-dependent control of electron transfer and central carbon pathway genes for methane biosynthesis in the archaean, methanosarcina acetivorans strain c2a. | the archaeon, methanosarcina acetivorans strain c2a forms methane, a potent greenhouse gas, from a variety of one-carbon substrates and acetate. whereas the biochemical pathways leading to methane formation are well understood, little is known about the expression of the many of the genes that encode proteins needed for carbon flow, electron transfer and/or energy conservation. quantitative transcript analysis was performed on twenty gene clusters encompassing over one hundred genes in m. acetiv ... | 2010 | 20178638 |
| zwittermicin a: synthesis of analogs and structure-activity studies. | analogs and diastereomers of the natural product zwittermicin a were prepared. sar studies of these compounds reveal the antifungal activity to be dependent singularly upon the natural constitution and configuration. | 2010 | 20189808 |
| quorum sensing-controlled evr regulates a conserved cryptic pigment biosynthetic cluster and a novel phenomycin-like locus in the plant pathogen, pectobacterium carotovorum. | pectobacterium carotovorum scri193 is a phytopathogenic gram-negative bacterium. in this study, we have identified a novel cryptic pigment biosynthetic locus in p. carotovorum scri193 which we have called the pectobacterium orange pigment (pop) cluster. the pop cluster is flanked by two trna genes and contains genes that encode non-ribosomal peptide synthases and polyketide synthase and produces a negatively charged polar orange pigment. orange pigment production is activated when an adjacent tr ... | 2010 | 20192973 |
| proteome analysis of fungal and bacterial involvement in leaf litter decomposition. | fungi and bacteria are key players in the decomposition of leaf litter, but their individual contributions to the process and their interactions are still poorly known. we combined semi-quantitative proteome analyses (1-d page-lc-ms/ms) with qualitative and quantitative analyses of extracellular degradative enzyme activities to unravel the respective roles of a fungus and a bacterium during litter decomposition. two model organisms, a mesophilic gram-negative bacterium (pectobacterium carotovoru ... | 2010 | 20198641 |
| specific maceration and induction of pr-3 gene in potato tuber tissue by pectobacterium carotovorum subsp. atrosepticum type iii secretion system mutants. | the exact function of type iii secretion system in some phytopathogenes including pectobacterium carotovorum subsp. atrosepticum (pca) is not understood and is a matter of debate. the aim of this study were to determine specific effect of type iii secretion system on potato tubers and to reveal the connection of this system with potato resistant genes such as pr-3. a pca hrpw fragment was subcloned into a low-copy-number cloning vector (pzh448). the resulting plasmid (pas19) was then conjugated ... | 2009 | 20334119 |
| cooperative regulation of the induction of the novel antibacterial listericin by peptidoglycan recognition protein le and the jak-stat pathway. | intracellular bacteria cause serious infectious diseases such as tuberculosis, shigellosis, and listeriosis. the drosophila peptidoglycan recognition protein (pgrp)-le functions as an important host pattern recognition receptor against intracellular bacteria such as listeria monocytogenes. one pgrp-le-mediated intracellular response against l. monocytogenes infection is the induction of autophagy, a conserved intracellular degradation system. here, to further elucidate pgrp-le-mediated intracell ... | 2010 | 20348097 |
| innate immune responses activated in arabidopsis roots by microbe-associated molecular patterns. | despite the fact that roots are the organs most subject to microbial interactions, very little is known about the response of roots to microbe-associated molecular patterns (mamps). by monitoring transcriptional activation of beta-glucuronidase reporters and mamp-elicited callose deposition, we show that three mamps, the flagellar peptide flg22, peptidoglycan, and chitin, trigger a strong tissue-specific response in arabidopsis thaliana roots, either at the elongation zone for flg22 and peptidog ... | 2010 | 20348432 |
| intercellular communication system of the enterobacterium erwinia carotovora adapting to unfavorable growth conditions. | | 2010 | 20380184 |
| role of the feob protein and siderophore in promoting virulence of xanthomonas oryzae pv. oryzae on rice. | xanthomonas oryzae pv. oryzae causes bacterial blight, a serious disease of rice. our analysis revealed that the x. oryzae pv. oryzae genome encodes genes responsible for iron uptake through feob (homolog of the major bacterial ferrous iron transporter) and a siderophore. a mutation in the x. oryzae pv. oryzae feob gene causes severe virulence deficiency, growth deficiency in iron-limiting medium, and constitutive production of a siderophore. we identified an iron regulated xss gene cluster, in ... | 2010 | 20382771 |
| huanglongbing, a systemic disease, restructures the bacterial community associated with citrus roots. | to examine the effect of pathogens on the diversity and structure of plant-associated bacterial communities, we carried out a molecular analysis using citrus and huanglongbing as a host-disease model. 16s rrna gene clone library analysis of citrus roots revealed shifts in microbial diversity in response to pathogen infection. the clone library of the uninfected root samples has a majority of phylotypes showing similarity to well-known plant growth-promoting bacteria, including caulobacter, burkh ... | 2010 | 20382817 |