| global transcriptome analysis of shewanella oneidensis mr-1 exposed to different terminal electron acceptors. | to gain insight into the complex structure of the energy-generating networks in the dissimilatory metal reducer shewanella oneidensis mr-1, global mrna patterns were examined in cells exposed to a wide range of metal and non-metal electron acceptors. gene expression patterns were similar irrespective of which metal ion was used as electron acceptor, with 60% of the differentially expressed genes showing similar induction or repression relative to fumarate-respiring conditions. several groups of ... | 2005 | 16199584 |
| intracellular screen to identify metagenomic clones that induce or inhibit a quorum-sensing biosensor. | the goal of this study was to design and evaluate a rapid screen to identify metagenomic clones that produce biologically active small molecules. we built metagenomic libraries with dna from soil on the floodplain of the tanana river in alaska. we extracted dna directly from the soil and cloned it into fosmid and bacterial artificial chromosome vectors, constructing eight metagenomic libraries that contain 53,000 clones with inserts ranging from 1 to 190 kb. to identify clones of interest, we de ... | 2005 | 16204555 |
| contrasting occurrence of chromobacterium violaceum in tropical drinking water springs of uganda. | occurrence of chromobacterium violaceum in six protected drinking water springs in uganda was investigated. c. violaceum showed a contrasting occurrence, which was independent of human impact as assessed by faecal pollution indicators. it was isolated from two springs (s1 and s2) that were located close to each other (3 km) but not in the rest. in s1 c. violaceum was continuously detected, in concentrations ranging from 6 to 270 cfu 100 ml(-1), while in s2 it was detected on only one sampling oc ... | 2005 | 16209027 |
| chromobacterium violaceum in siblings, brazil. | chromobacterium violaceum, a saprophyte bacterium found commonly in soil and water in tropical and subtropical climates, is a rare cause of severe, often fatal, human disease. we report 1 confirmed and 2 suspected cases of c. violaceum septicemia, with 2 fatalities, in siblings after recreational exposure in northeastern brazil. | 2005 | 16229777 |
| effective extraction of elastase from bacillus sp. fermentation broth using aqueous two-phase system. | this paper presents the evaluation of an aqueous two-phase system (atps) for extracting elastase produced by bacillus sp. el31410. the elastase and cell partition behavior in polyethylene glycol (peg)/salt systems was investigated. the suitable system for elastase extraction was peg/kh(2)po(4)-k(2)hpo(4), in which elastase is mainly partitioned into the peg-rich phase, while the cells remained in the other phase. the influence of defined system parameters (e.g. peg molecular mass, ph, nacl addit ... | 2005 | 16252343 |
| n-butanoyl-l-homoserine lactone (bhl) deficient pseudomonas aeruginosa isolates from an intensive care unit. | acylated homoserine lactones (ahls) are self-generated diffusible signal molecules that mediate population density dependent gene expression (quorum sensing) in a variety of gram-negative bacteria, and several virulence genes of human pathogens are known to be controlled by ahls. in this study, strains of pseudomonas aeruginosa, acinetobacter baumannii, escherichia coli and klebsiella pneumoniae, isolated from intensive care patients, were screened for ahl production by using ahl responsive indi ... | 2005 | 16255145 |
| a case of chromobacterium infection after car accident in korea. | chromobacterium violaceum is a gram negative straight rod, 0.8-1.2 by 2.5 to 6.0 m, which is motile by one polar flagella and one to four lateral flagella. the organism inhabits soil and water and is often found in semitropical and tropical climates. infections in humans are rare. we report a case of infection caused by strains of c. violaceum. a 38-year-old male patient was admitted to kyunghee university hospital, seoul, korea on july 28th, 2003, after a car accident. the patient had multiple ... | 2005 | 16259070 |
| dissimilatory metabolism of nitrogen oxides in bacteria: comparative reconstruction of transcriptional networks. | bacterial response to nitric oxide (no) is of major importance since no is an obligatory intermediate of the nitrogen cycle. transcriptional regulation of the dissimilatory nitric oxides metabolism in bacteria is diverse and involves fnr-like transcription factors hcpr, dnr, and nnrr; two-component systems narxl and narqp; no-responsive activator norr; and nitrite-sensitive repressor nsrr. using comparative genomics approaches, we predict dna-binding motifs for these transcriptional factors and ... | 2005 | 16261196 |
| polyphenol oxidase activity expression in ralstonia solanacearum. | sequencing of the genome of ralstonia solanacearum revealed several genes that putatively code for polyphenol oxidases (ppos). to study the actual expression of these genes, we looked for and detected all kinds of ppo activities, including laccase, cresolase, and catechol oxidase activities, in cellular extracts of this microorganism. the conditions for the ppo assays were optimized for the phenolic substrate, ph, and sodium dodecyl sulfate concentration used. it was demonstrated that three diff ... | 2005 | 16269713 |
| evidence for a functional quorum-sensing type ai-1 system in the extremophilic bacterium acidithiobacillus ferrooxidans. | acidithiobacillus ferrooxidans is one of the main acidophilic chemolithotrophic bacteria involved in the bioleaching of metal sulfide ores. the bacterium-mineral interaction requires the development of biofilms, whose formation is regulated in many microorganisms by type ai-1 quorum sensing. here, we report the existence and characterization of a functional type ai-1 quorum-sensing system in a. ferrooxidans. this microorganism produced mainly acyl-homoserine lactones (ahl) with medium and large ... | 2005 | 16269739 |
| ecology, inhibitory activity, and morphogenesis of a marine antagonistic bacterium belonging to the roseobacter clade. | roseobacter strain 27-4 has been isolated from a turbot larval rearing unit and is capable of reducing mortality in turbot egg yolk sac larvae. here, we demonstrate that the supernatant of roseobacter 27-4 is lethal to the larval pathogens vibrio anguillarum and vibrio splendidus in a buffer system and inhibited their growth in marine broth. liquid chromatography (lc) with both uv spectral detection and high-resolution mass spectrometry (hr-ms) identified the known antibacterial compound thiotro ... | 2005 | 16269767 |
| coiled-coil protein composition of 22 proteomes--differences and common themes in subcellular infrastructure and traffic control. | long alpha-helical coiled-coil proteins are involved in diverse organizational and regulatory processes in eukaryotic cells. they provide cables and networks in the cyto- and nucleoskeleton, molecular scaffolds that organize membrane systems and tissues, motors, levers, rotating arms, and possibly springs. mutations in long coiled-coil proteins have been implemented in a growing number of human diseases. using the coiled-coil prediction program multicoil, we have previously identified all long c ... | 2005 | 16288662 |
| four-helix bundle: a ubiquitous sensory module in prokaryotic signal transduction. | motivation: transmembrane chemoreceptors in escherichia coli utilize ligand-binding domains for detecting various external signals. the structure of this domain in the e.coli aspartate receptor, tar, is known and its signal transduction mechanism is under investigation. current domain models for this important sensory module are inaccurate and, therefore, cannot reveal the distribution of this domain within the current genomic landscape. results: we carried out sensitive and exhaustive psi-blast ... | 2005 | 16306392 |
| l-canavanine made by medicago sativa interferes with quorum sensing in sinorhizobium meliloti. | sinorhizobium meliloti is a gram-negative soil bacterium, capable of establishing a nitrogen-fixing symbiosis with its legume host, alfalfa (medicago sativa). quorum sensing plays a crucial role in this symbiosis, where it influences the nodulation process and the synthesis of the symbiotically important exopolysaccharide ii (eps ii). s. meliloti has three quorum-sensing systems (sin, tra, and mel) that use n-acyl homoserine lactones as their quorum-sensing signal molecule. increasing evidence i ... | 2005 | 16321947 |
| cell-cell influences on bacterial community development in aquatic biofilms. | dialysis tubing containing spent culture media, when placed in a lake, was colonized by a low diversity of bacteria, whereas abiotic controls had considerable diversity. changes were seen in the presence and absence of acylated homoserine lactones, suggesting that these molecules and other factors may influence adherent-population composition. | 2005 | 16332906 |
| production of acylated homoserine lactones by aeromonas and pseudomonas strains isolated from municipal activated sludge. | up to now, the production and role of n-acyl homoserine lactones (ahls) in activated sludge have been poorly understood. in this study, cross-feeding assays with the reporter strains agrobacterium tumefaciens ntl4 and chromobacterium violaceum cv026 were used to investigate ahl signal production by municipal activated sludge samples. ahl signal production was consistently detected from municipal activated sludge when different samples were incubated on nutrient media. from one municipal activate ... | 2005 | 16333331 |
| violacein synergistically increases 5-fluorouracil cytotoxicity, induces apoptosis and inhibits akt-mediated signal transduction in human colorectal cancer cells. | despite recent additions to the armory of chemotherapeutic agents for colorectal cancer (crc) treatment, the results of chemotherapy remain unsatisfactory. 5-fluorouracil (5-fu) still represents the cornerstone of treatment and resistance to its actions is a major obstacle to successful chemotherapy. therefore, new active agents in crc and agents that increase the chemosensitivity of cancer cells to 5-fu are still urgently required. violacein, a pigment isolated from chromobacterium violaceum in ... | 2006 | 16344270 |
| denitrification by chromobacterium violaceum. | one host (rana catesbiana)-associated and two free-living mesophilic strains of bacteria with violet pigmentation and biochemical characteristics of chromobacterium violaceum were isolated from freshwater habitats. cells of each freshly isolated strain and of strain atcc 12472 (the neotype strain) grew anaerobically with glucose as the sole carbon and energy source. the major fermentation products of cells grown in trypticase soy broth (bbl microbiology systems, cockeysville, md.) supplemented w ... | 1986 | 16347164 |
| in vitro testing for genotoxicity of violacein assessed by comet and micronucleus assays. | chromobacterium violaceum is a gram (-) bacteria found in water samples and soils from tropical and subtropical regions of the world. violacein, the major pigment produced by these bacteria, has been shown to have antibiotic, antitumoral and trypanocidal activities. in the present work, the genotoxicity of violacein was investigated in four different cell lines by using the alkaline comet assay and in vero cells using the micronucleus test. in the alkaline comet assay, violacein, when tested at ... | 2006 | 16359912 |
| xbase, a collection of online databases for bacterial comparative genomics. | the schema of the previously described escherischia coli database colibase has been applied to a number of other bacterial taxa, under the collective name xbase. the new databases include campydb for campylobacter, helicobacter and wolinella; pseudodb for pseudomonads; clostridb for clostridia; rhizodb for rhizobium and sinorhizobium; and mycodb, for mycobacterium, streptomyces and related organisms. the databases provide user friendly access to annotation and genome comparisons through a web-ba ... | 2006 | 16381881 |
| xbase, a collection of online databases for bacterial comparative genomics. | the schema of the previously described escherischia coli database colibase has been applied to a number of other bacterial taxa, under the collective name xbase. the new databases include campydb for campylobacter, helicobacter and wolinella; pseudodb for pseudomonads; clostridb for clostridia; rhizodb for rhizobium and sinorhizobium; and mycodb, for mycobacterium, streptomyces and related organisms. the databases provide user friendly access to annotation and genome comparisons through a web-ba ... | 2006 | 16381881 |
| specificity of acyl-homoserine lactone synthases examined by mass spectrometry. | many gram-negative bacteria produce a specific set of n-acyl-l-homoserine-lactone (ahl) signaling molecules for the purpose of quorum sensing, which is a means of regulating coordinated gene expression in a cell-density-dependent manner. ahls are produced from acylated acyl-carrier protein (acyl-acp) and s-adenosyl-l-methionine by the ahl synthase enzyme. the appearance of specific ahls is due in large part to the intrinsic specificity of the enzyme for subsets of acyl-acp substrates. structural ... | 2006 | 16385066 |
| quorum-sensing signal synthesis by the yersinia pestis acyl-homoserine lactone synthase yspi. | the acyl-homoserine lactone molecular species (ahls) produced by the yersinia pestis ahl synthase yspi were identified by biochemical and physical/chemical techniques. bioassays of extracts from culture supernatants of the recombinant yspi and wild-type yersinia pestis showed similar profiles of ahls. analysis by liquid chromatography-mass spectrometry revealed that the predominant ahls were n-3-oxooctanoyl-l-homoserine lactone and n-3-oxo-hexanoyl-l-homoserine lactone. | 2006 | 16385067 |
| development and evaluation of a real-time pcr assay targeting the type iii secretion system of burkholderia pseudomallei. | here we report on the development of a discriminatory real-time assay for the rapid identification of burkholderia pseudomallei isolates and the evaluation of this assay for sensitivity against related species and detection in spiked human blood samples. the assay targets a 115-base-pair region within orf2 of the b. pseudomallei type iii secretion system gene cluster and distinguishes b. pseudomallei from other microbial species. assay performance was evaluated with 224 geographically, temporall ... | 2006 | 16390953 |
| anaerobic nitrate-dependent iron(ii) bio-oxidation by a novel lithoautotrophic betaproteobacterium, strain 2002. | microbial nitrate-dependent fe(ii) oxidation is known to contribute to iron biogeochemical cycling; however, the microorganisms responsible are virtually unknown. in an effort to elucidate this microbial metabolic process in the context of an environmental system, a 14-cm sediment core was collected from a freshwater lake and geochemically characterized concurrently with the enumeration of the nitrate-dependent fe(ii)-oxidizing microbial community and subsequent isolation of a nitrate-dependent ... | 2006 | 16391108 |
| anti-quorum sensing activity of medicinal plants in southern florida. | bacterial intercellular communication, or quorum sensing (qs), controls the pathogenesis of many medically important organisms. anti-qs compounds are known to exist in marine algae and have the ability to attenuate bacterial pathogenicity. we hypothesized that terrestrial plants traditionally used as medicines may also produce anti-qs compounds. to test this hypothesis, 50 medicinal plants from southern florida were screened for anti-qs activity using two biomonitor strains, chromobacterium viol ... | 2006 | 16406418 |
| [chromobacteriosis in ilhéus, bahia: epidemiologic, clinical and laboratorial investigation]. | in april/2004, a group of people traveled to a farm in a town in the south of bahia and afterwards, three teenagers from the same family developed symptoms of severe septicemia and two died. the health department carried out an epidemiologic, clinical, laboratory and environmental investigation that resulted in the identification of chromobacterium violaceum, in biological material from one of them, water and soil. this is the first report of the disease in bahia state. | 2006 | 16410927 |
| canine adenovirus vectors for lung-directed gene transfer: efficacy, immune response, and duration of transgene expression using helper-dependent vectors. | a major hurdle to the successful clinical use of some viral vectors relates to the innate, adaptive, and memory immune responses that limit the efficiency and duration of transgene expression. some of these drawbacks may be circumvented by using vectors derived from nonhuman viruses such as canine adenovirus type 2 (cav-2). here, we evaluated the potential of cav-2 vectors for gene transfer to the respiratory tract. we found that cav-2 transduction was efficient in vivo in the mouse respiratory ... | 2006 | 16415025 |
| detection of chromobacterium violaceum by multiplex pcr targeting the prgi, spao, invg, and sipb genes. | based on the recently completed genomic sequence of chromobacterium violaceum american type culture collection (atcc) 12472 a multiplex pcr assay targeting the prgi, spao, invg, and sipb genes of the salmonella spi-1 homologue type-iii secretion system was developed. pcr products of 255bp (prgi), 749bp (spao), 1685bp (invg), and 1752bp (sipb) were successfully amplified simultaneously in a single reaction with all chr. violaceum strains investigated whereas other bacteria tested negative. the de ... | 2006 | 16423655 |
| analysis of the lateral flagellar gene system of aeromonas hydrophila ah-3. | mesophilic aeromonas strains express a polar flagellum in all culture conditions, and certain strains produce lateral flagella on semisolid media or on surfaces. although aeromonas lateral flagella have been described as a colonization factor, little is known about their organization and expression. here we characterized the complete lateral flagellar gene cluster of aeromonas hydrophila ah-3 containing 38 genes, 9 of which (lafa-u) have been reported previously. among the flgll and lafa structu ... | 2006 | 16428388 |
| n-acylhomoserine lactones antagonize virulence gene expression and quorum sensing in staphylococcus aureus. | many gram-negative bacteria employ n-acylhomoserine lactone (ahl)-mediated quorum sensing to control virulence. to determine whether gram-positive bacteria such as staphylococcus aureus respond to ahls, we used a growth-dependent lux reporter fusion. exposure of s. aureus to different ahls revealed that 3-oxo-substituted ahls with c10 to c14 acyl chains inhibited light output and growth in a concentration-dependent manner, while short-chain ahls had no effect. n-(3-oxododecanoyl)-l-homoserine la ... | 2006 | 16428734 |
| the use of violacein to study biochemical behaviour of saccharomyces cerevisiae cells. | violacein, a biochemical compound produced by chromobacterium violaceum which has antichagasic properties, was used to study biochemical behaviour of saccharomyces cerevisiae cells. at 20 microm and 40 microm, violacein did not alter the membrane potential (deltapsi) of s. cerevisae cells, which means that the integrity of the cell membrane was maintained. on the other hand, at 60 microm and 80 microm, violacein produced significant alterations in the membrane potential. this information will be ... | 2005 | 16435565 |
| blast screening of chlamydial genomes to identify signature proteins that are unique for the chlamydiales, chlamydiaceae, chlamydophila and chlamydia groups of species. | chlamydiae species are of much importance from a clinical viewpoint. their diversity both in terms of their numbers as well as clinical involvement are presently believed to be significantly underestimated. the obligate intracellular nature of chlamydiae has also limited their genetic and biochemical studies. thus, it is of importance to develop additional means for their identification and characterization. | 2006 | 16436211 |
| production and properties of the native chromobacterium violaceum fucose-binding lectin (cv-iil) compared to homologous lectins of pseudomonas aeruginosa (pa-iil) and ralstonia solanacearum (rs-iil). | chromobacterium violaceum is a versatile, violet pigment (violacein)-producing beta-proteobacterium, confined to tropical and subtropical regions, dwelling in soil and water, like pseudomonas aeruginosa and ralstonia solanacearum. these three bacteria are saprophytes that occasionally become aggressive opportunistic pathogens virulently attacking animals (the first two) and plants (the third). the recent availability of their genome sequences enabled identification in the c. violaceum genome of ... | 2006 | 16436433 |
| an investigation of chlorophenol proton affinities and their influence on the biological activity of microorganisms. | the proton affinities of 15 chlorophenols are calculated by ab initio methods. straight correlation between proton affinities and changes in the electronic structure is observed. the proton affinities decrease linearly with the electronic density gain on the chlorine atoms, as the liberation of the proton increases. to confirm the importance of the proton affinities on the toxicity of chlorophenols, calorimetric responses of these molecules and related ones where the acid proton is changed to a ... | 2006 | 16451037 |
| quorum sensing in yersinia enterocolitica controls swimming and swarming motility. | the yersinia enterocolitica luxi homologue yeni directs the synthesis of n-3-(oxohexanoyl)homoserine lactone (3-oxo-c6-hsl) and n-hexanoylhomoserine lactone (c6-hsl). in a y. enterocolitica yeni mutant, swimming motility is temporally delayed while swarming motility is abolished. since both swimming and swarming are flagellum dependent, we purified the flagellin protein from the parent and yeni mutant. electrophoresis revealed that in contrast to the parent strain, the yeni mutant grown for 17 h ... | 2006 | 16452428 |
| the genome sequence of the obligately chemolithoautotrophic, facultatively anaerobic bacterium thiobacillus denitrificans. | the complete genome sequence of thiobacillus denitrificans atcc 25259 is the first to become available for an obligately chemolithoautotrophic, sulfur-compound-oxidizing, beta-proteobacterium. analysis of the 2,909,809-bp genome will facilitate our molecular and biochemical understanding of the unusual metabolic repertoire of this bacterium, including its ability to couple denitrification to sulfur-compound oxidation, to catalyze anaerobic, nitrate-dependent oxidation of fe(ii) and u(iv), and to ... | 2006 | 16452431 |
| a mobile quorum-sensing system in serratia marcescens. | quorum-sensing systems that have been widely identified in bacteria play important roles in the regulation of bacterial multicellular behavior by which bacteria sense population density to control various biological functions, including virulence. one characteristic of the luxir quorum-sensing genes is their diverse and discontinuous distribution among proteobacteria. here we report that the spnir quorum-sensing system identified in the enterobacterium serratia marcescens strain ss-1 is carried ... | 2006 | 16452435 |
| coexistence of burkholderia, cupriavidus, and rhizobium sp. nodule bacteria on two mimosa spp. in costa rica. | rrna gene sequencing and pcr assays indicated that 215 isolates of root nodule bacteria from two mimosa species at three sites in costa rica belonged to the genera burkholderia, cupriavidus, and rhizobium. this is the first report of cupriavidus sp. nodule symbionts for mimosa populations within their native geographic range in the neotropics. burkholderia spp. predominated among samples from mimosa pigra (86% of isolates), while there was a more even distribution of cupriavidus, burkholderia, a ... | 2006 | 16461667 |
| quorum quenching by an n-acyl-homoserine lactone acylase from pseudomonas aeruginosa pao1. | the virulence of the opportunistic human pathogen pseudomonas aeruginosa pao1 is controlled by an n-acyl-homoserine lactone (ahl)-dependent quorum-sensing system. during functional analysis of putative acylase genes in the p. aeruginosa pao1 genome, the pa2385 gene was found to encode an acylase that removes the fatty acid side chain from the homoserine lactone (hsl) nucleus of ahl-dependent quorum-sensing signal molecules. analysis showed that the posttranslational processing of the acylase and ... | 2006 | 16495538 |
| identification of a meningococcal l-glutamate abc transporter operon essential for growth in low-sodium environments. | gdhr is a meningococcal transcriptional regulator that was previously shown to positively control the expression of gdha, encoding the nadp-specific l-glutamate dehydrogenase (nadp-gdh), in response to the growth phase and/or to the carbon source. in this study we used reverse transcriptase-pcr-differential display (to identify additional gdhr-regulated genes. the results indicated that gdhr, in addition to nadp-gdh, controls the expression of a number of genes involved in glucose catabolism by ... | 2006 | 16495545 |
| expression, purification, crystallization and preliminary x-ray analysis of yaeq (xac2396) from xanthomonas axonopodis pv. citri. | xanthomonas axonopodis pv. citri yaeq (xac2396) is a member of a family of bacterial proteins conserved in several gram-negative pathogens. here, the cloning, expression, purification and crystallization of the 182-residue (20.6 kda) yaeq protein are described. recombinant yaeq containing selenomethionine was crystallized in space group p2(1) and crystals diffracted to 1.9 a resolution at a synchrotron source. the unit-cell parameters are a = 39.75, b = 91.88, c = 48.03 a, beta = 108.37 degrees. ... | 2005 | 16511077 |
| chromobacterium violaceum infection in two dogs. | chromobacterium violaceum is a saprophyte of soil and water in tropical and subtropical environments that is associated with rare but highly fatal infections in animals and humans. systemic infection was diagnosed in two critically ill dogs from florida. fever was absent in both dogs. both dogs were treated surgically and provided with intensive care, but only one survived. the identification of characteristic, violet-pigmented bacterial colonies on routine microbial cultures should alert microb ... | 2006 | 16527917 |
| genetic diversity of the q fever agent, coxiella burnetii, assessed by microarray-based whole-genome comparisons. | coxiella burnetii, a gram-negative obligate intracellular bacterium, causes human q fever and is considered a potential agent of bioterrorism. distinct genomic groups of c. burnetii are revealed by restriction fragment-length polymorphisms (rflp). here we comprehensively define the genetic diversity of c. burnetii by hybridizing the genomes of 20 rflp-grouped and four ungrouped isolates from disparate sources to a high-density custom affymetrix genechip containing all open reading frames (orfs) ... | 2006 | 16547017 |
| the antimicrobial activity of marinocine, synthesized by marinomonas mediterranea, is due to hydrogen peroxide generated by its lysine oxidase activity. | marinocine is a broad-spectrum antibacterial protein synthesized by the melanogenic marine bacterium marinomonas mediterranea. this work describes the basis for the antibacterial activity of marinocine and the identification of the gene coding for this protein. the antibacterial activity is inhibited under anaerobic conditions and by the presence of catalase under aerobic conditions. marinocine is active only in culture media containing l-lysine. in the presence of this amino acid, marinocine ge ... | 2006 | 16547036 |
| genomic organization and molecular characterization of clostridium difficile bacteriophage phicd119. | in this study, we have isolated a temperate phage (phicd119) from a pathogenic clostridium difficile strain and sequenced and annotated its genome. this virus has an icosahedral capsid and a contractile tail covered by a sheath and contains a double-stranded dna genome. it belongs to the myoviridae family of the tailed phages and the order caudovirales. the genome was circularly permuted, with no physical ends detected by sequencing or restriction enzyme digestion analysis, and lacked a cos site ... | 2006 | 16547044 |
| gem system: automatic prototyping of cell-wide metabolic pathway models from genomes. | successful realization of a "systems biology" approach to analyzing cells is a grand challenge for our understanding of life. however, current modeling approaches to cell simulation are labor-intensive, manual affairs, and therefore constitute a major bottleneck in the evolution of computational cell biology. | 2006 | 16553966 |
| chromobacterium violaceum, var. manilae as a pathogenic microörganism. | | 1942 | 16560589 |
| recreational and occupational field exposure to freshwater cyanobacteria--a review of anecdotal and case reports, epidemiological studies and the challenges for epidemiologic assessment. | cyanobacteria are common inhabitants of freshwater lakes and reservoirs throughout the world. under favourable conditions, certain cyanobacteria can dominate the phytoplankton within a waterbody and form nuisance blooms. case reports and anecdotal references dating from 1949 describe a range of illnesses associated with recreational exposure to cyanobacteria: hay fever-like symptoms, pruritic skin rashes and gastro-intestinal symptoms are most frequently reported. some papers give convincing des ... | 2006 | 16563159 |
| cyanobacterial lipopolysaccharides and human health - a review. | cyanobacterial lipopolysaccharide/s (lps) are frequently cited in the cyanobacteria literature as toxins responsible for a variety of heath effects in humans, from skin rashes to gastrointestinal, respiratory and allergic reactions. the attribution of toxic properties to cyanobacterial lps dates from the 1970s, when it was thought that lipid a, the toxic moiety of lps, was structurally and functionally conserved across all gram-negative bacteria. however, more recent research has shown that this ... | 2006 | 16563160 |
| effects of cyanide and dissolved oxygen concentration on biological au recovery. | the number of discarded electric devices containing traces of au is currently increasing. it is desirable to recover this au because of its valuable physicochemical properties. au is usually dissolved with relatively high concentrations of cyanide, which is associated with environmental risk. chromobacterium violaceum is able to produce and detoxify small amounts of cyanide, and may thus be able to recover au from discarded electric devices. this study investigated the effects of cyanide and dis ... | 2006 | 16567012 |
| important unusual infections in australia: a critical care perspective. | to review a number of the important unusual infections in australia that can lead to critical illness. | 2001 | 16573516 |
| aquitalea magnusonii gen. nov., sp. nov., a novel gram-negative bacterium isolated from a humic lake. | a gram-negative, rod-shaped, non-spore-forming betaproteobacterium (tro-001dr8t) was isolated from humic-lake samples collected from northern wisconsin, usa. on the basis of 16s rrna gene sequence analysis, strain tro-001dr8t belonged to the family neisseriaceae, and the phylogenetic distance from its closest relative, chromobacterium violaceum, was 95 %. strain tro-001dr8t lacked the violet pigmentation of c. violaceum and shared only 26 % dna-dna relatedness with c. violaceum. the dna g+c cont ... | 2006 | 16585708 |
| use of a variable amplicon typing scheme reveals considerable variation in the accessory genomes of isolates of burkholderia pseudomallei. | melioidosis, a disease caused by the bacterium burkholderia pseudomallei, is endemic in southeast asia and northern australia. we used suppression subtractive hybridization (ssh) to identify sequences that varied between two b. pseudomallei isolates from australia and determined the distribution of 45 ssh-derived sequences among a panel of b. pseudomallei and b. thailandensis isolates. sequences exhibiting variable prevalence were included in a variable amplicon typing (vat) scheme designed to s ... | 2006 | 16597858 |
| cloning and sequencing of the ompa gene of enterobacter sakazakii and development of an ompa-targeted pcr for rapid detection of enterobacter sakazakii in infant formula. | enterobacter sakazakii is an emerging, infant formula-borne pathogen that causes severe meningitis, meningoencephalitis, sepsis, and necrotizing enterocolitis in neonates and infants, with a high fatality rate. traditional detection methods take up to 7 days to identify e. sakazakii. the outer membrane protein a gene (ompa), along with its flanking sequences from e. sakazakii (atcc 51329), was cloned in the pgem-t easy vector and sequenced. comparison of the nucleotide and deduced amino acid seq ... | 2006 | 16597955 |
| a phylogenomic profile of globins. | globins occur in all three kingdoms of life: they can be classified into single-domain globins and chimeric globins. the latter comprise the flavohemoglobins with a c-terminal fad-binding domain and the gene-regulating globin coupled sensors, with variable c-terminal domains. the single-domain globins encompass sequences related to chimeric globins and "truncated" hemoglobins with a 2-over-2 instead of the canonical 3-over-3 alpha-helical fold. | 2006 | 16600051 |
| a flexible loop in tyrosine hydroxylase controls coupling of amino acid hydroxylation to tetrahydropterin oxidation. | the role of a polypeptide loop in tyrosine hydroxylase (tyrh) whose homolog in phenylalanine hydroxylase (pheh) takes on a different conformation when substrates are bound has been studied using site-directed mutagenesis. the loop spans positions 177 to 191; alanine was introduced into those positions, introducing one alanine substitution per tyrh variant. mutagenesis of residues in the center of the loop resulted in alterations in the km values for substrates, the vmax value for dihydroxyphenyl ... | 2006 | 16618490 |
| ecthyma gangrenosum and septic shock syndrome secondary to chromobacterium violaceum. | chromobacterium violaceum is a gram-negative bacterium of soil and water in tropical and subtropical environments. typically, it is considered a bacterium of low virulence although, uncommonly, it causes human infection, particularly in persons with defects in host defenses. infection generally follows exposure of broken skin to contaminated water and soil, and is often characterized by pustules, lymphadenitis, fever, and vomiting, as well as rapid dissemination and a high mortality rate. unfort ... | 2006 | 16631946 |
| application of comparative phylogenomics to study the evolution of yersinia enterocolitica and to identify genetic differences relating to pathogenicity. | yersinia enterocolitica, an important cause of human gastroenteritis generally caused by the consumption of livestock, has traditionally been categorized into three groups with respect to pathogenicity, i.e., nonpathogenic (biotype 1a), low pathogenicity (biotypes 2 to 5), and highly pathogenic (biotype 1b). however, genetic differences that explain variation in pathogenesis and whether different biotypes are associated with specific nonhuman hosts are largely unknown. in this study, we applied ... | 2006 | 16672618 |
| role of the fur regulon in iron transport in bacillus subtilis. | the bacillus subtilis ferric uptake regulator (fur) protein mediates the iron-dependent repression of at least 20 operons encoding approximately 40 genes. we investigated the physiological roles of fur-regulated genes by the construction of null mutations in 14 transcription units known or predicted to function in siderophore biosynthesis or iron uptake. we demonstrate that ywblmn, encoding an elemental iron uptake system orthologous to the copper oxidase-dependent fe(iii) uptake system of sacch ... | 2006 | 16672620 |
| epr and uv-vis studies of the nitric oxide adducts of bacterial phenylalanine hydroxylase: effects of cofactor and substrate on the iron environment. | phenylalanine hydroxylase from chromobacterium violaceum (cpah), which catalyzes phenylalanine oxidation to tyrosine, is homologous to the catalytic domain of eukaryotic pahs. previous crystallographic and spectroscopic studies on mammalian pah conflict on whether o2 binds to the open-coordination site or displaces the remaining water ligand to yield either a six- or a five-coordinate iron, respectively. the abilities of nitric oxide to behave as an oxygen mimic and a spectroscopic probe of ferr ... | 2006 | 16676991 |
| chromobacterium violaceum infection. | | 2006 | 16681318 |
| detecting uber-operons in prokaryotic genomes. | we present a study on computational identification of uber-operons in a prokaryotic genome, each of which represents a group of operons that are evolutionarily or functionally associated through operons in other (reference) genomes. uber-operons represent a rich set of footprints of operon evolution, whose full utilization could lead to new and more powerful tools for elucidation of biological pathways and networks than what operons have provided, and a better understanding of prokaryotic genome ... | 2006 | 16682449 |
| inhibition of bacterial quorum sensing by vanilla extract. | the purpose of this study was to search for a novel quorum sensing inhibitor and analyse its inhibitory activity. | 2006 | 16706905 |
| on the pigment produced by chromobacterium violaceum. | | 1927 | 16743932 |
| a constitutively expressed, truncated umudc operon regulates the reca-dependent dna damage induction of a gene in acinetobacter baylyi strain adp1. | in response to environmentally caused dna damage, sos genes are up-regulated due to reca-mediated relief of lexa repression. in escherichia coli, the sos umudc operon is required for dna damage checkpoint functions and for replicating damaged dna in the error-prone process called sos mutagenesis. in the model soil bacterium acinetobacter baylyi strain adp1, however, the content, regulation, and function of the umudc operon are unusual. the umuc gene is incomplete, and a remnant of an isehe3-like ... | 2006 | 16751513 |
| structure of the pii signal transduction protein of neisseria meningitidis at 1.85 a resolution. | the p(ii) signal transduction proteins glnb and glnk are implicated in the regulation of nitrogen assimilation in escherichia coli and other enteric bacteria. p(ii)-like proteins are widely distributed in bacteria, archaea and plants. in contrast to other bacteria, neisseria are limited to a single p(ii) protein (nmb 1995), which shows a high level of sequence identity to glnb and glnk from escherichia coli (73 and 62%, respectively). the structure of the p(ii) protein from n. meningitidis (sero ... | 2006 | 16754965 |
| fatal septicaemia from chromobacterium violaceum: case reports and review of the literature. | chromobacterium violaceum rarely causes infection in humans and its mechanism of pathogenicity is not well understood. human infection carries a high mortality rate with a fulminating clinical progression. a high index of suspicion is required for diagnosis, and is based on recovering the organisms from blood cultures or other appropriate specimens. we present three cases of human infection managed in a tertiary referral hospital in hong kong with a review of the literature. | 2006 | 16760554 |
| unusual entropy-driven affinity of chromobacterium violaceum lectin cv-iil toward fucose and mannose. | the purple pigmented bacterium chromobacterium violaceum is a dominant component of tropical soil microbiota that can cause rare but fatal septicaemia in humans. its sequenced genome provides insight into the abundant potential of this organism for biotechnological and pharmaceutical applications and allowed an orf encoding a protein that is 60% identical to the fucose binding lectin (pa-iil) from pseudomonas aeruginosa and the mannose binding lectin (rs-iil) from ralstonia solanacearum to be id ... | 2006 | 16768446 |
| genomic analysis of carbon source metabolism of shewanella oneidensis mr-1: predictions versus experiments. | genomic sequences have been used to find the genetic foundation for carbon source metabolism in shewanella oneidensis mr-1. annotated s. oneidensis mr-1 gene products were examined for their sequence similarity to enzymes participating in pathways for utilization of carbon and energy as described in the biocyc database (http://www.biocyc.org/) or in the primary literature. a picture emerges that relegates five- and six-carbon sugars to minor roles as carbon sources, whereas multiple pathways for ... | 2006 | 16788168 |
| [chromobacterium violaceum peritonitis: case report and literature review]. | we report a case of chromobacterium violaceum infection and we review the literature for all published cases. c. violaceum grew from a peritoneal fluid of a 47-year-old woman operated on for peritonitis following perforative gastroduodenal ulcer. she was just coming back from a 1-month-holyday in french guyana, where she might have been in contact with this micro-organism. the patient fully recovered after surgical management associated with antibiotic therapy consisting of ofloxacin plus pipera ... | 2006 | 16829475 |
| rooting the tree of life by transition analyses. | despite great advances in clarifying the family tree of life, it is still not agreed where its root is or what properties the most ancient cells possessed--the most difficult problems in phylogeny. protein paralogue trees can theoretically place the root, but are contradictory because of tree-reconstruction artefacts or poor resolution; ribosome-related and dna-handling enzymes suggested one between neomura (eukaryotes plus archaebacteria) and eubacteria, whereas metabolic enzymes often place it ... | 2006 | 16834776 |
| identification and characterization of bacterial cysteine dioxygenases: a new route of cysteine degradation for eubacteria. | in metazoa and fungi, the catabolic dissimilation of cysteine begins with its sulfoxidation to cysteine sulfinic acid by the enzyme cysteine dioxygenase (cdo). in these organisms, cdo plays an important role in the homeostatic regulation of steady-state cysteine levels and provides important oxidized metabolites of cysteine such as sulfate and taurine. to date, there has been no experimental evidence for the presence of cdo in prokaryotes. using psi-blast searches and crystallographic informatio ... | 2006 | 16855246 |
| cytotoxic activity of violacein in human colon cancer cells. | several studies have shown that violacein, a purple pigment extracted from chromobacterium violaceum, is capable to induce apoptosis in a variety of cancer cells, including those leukemia cell lines. herein, we examined the effects of violacein on reactive oxygen species (ros) production during the apoptotic colon cancer cell death. we demonstrate that violacein mediates ros production followed by activation of caspase-3, release of cytochrome c, and calcium release to citosol in caco-2 cells. m ... | 2006 | 16889929 |
| roles of the host oxidative immune response and bacterial antioxidant rubrerythrin during porphyromonas gingivalis infection. | the efficient clearance of microbes by neutrophils requires the concerted action of reactive oxygen species and microbicidal components within leukocyte secretory granules. rubrerythrin (rbr) is a nonheme iron protein that protects many air-sensitive bacteria against oxidative stress. using oxidative burst-knockout (nadph oxidase-null) mice and an rbr gene knockout bacterial strain, we investigated the interplay between the phagocytic oxidative burst of the host and the oxidative stress response ... | 2006 | 16895445 |
| evolution of vitamin b2 biosynthesis: 6,7-dimethyl-8-ribityllumazine synthases of brucella. | the penultimate step in the biosynthesis of riboflavin (vitamin b2) involves the condensation of 3,4-dihydroxy-2-butanone 4-phosphate with 5-amino-6-ribitylamino-2,4(1h,3h)-pyrimidinedione, which is catalyzed by 6,7-dimethyl-8-ribityllumazine synthase (lumazine synthase). pathogenic brucella species adapted to an intracellular lifestyle have two genes involved in riboflavin synthesis, ribh1 and ribh2, which are located on different chromosomes. the ribh2 gene was shown previously to specify a lu ... | 2006 | 16923880 |
| expression, purification, crystallization and preliminary crystallographic analysis of bipd, a component of the burkholderia pseudomallei type iii secretion system. | a construct consisting of residues 10-310 of bipd, a component of the burkholderia pseudomallei type iii secretion system (t3ss), has been overexpressed as a gst fusion, cleaved from the gst tag and purified. crystals were grown of native and selenomethionine-labelled bipd. the crystals grow in two different polymorphs from the same condition. the first polymorph belongs to space group c222, with unit-cell parameters a = 103.98, b = 122.79, c = 49.17 a, a calculated matthews coefficient of 2.4 a ... | 2006 | 16946464 |
| two 2[5h]-furanones as possible signaling molecules in lactobacillus helveticus. | two 2[5h]-furanones, in association with medium-chain fatty acids, were released in whey by lactobacillus helveticus exposed to oxidative and heat stresses. this species plays an important role in cheese technology, particularly for swiss-type cheeses and grana cheese. moreover, it significantly contributes to cheese ripening by means of an early autolysis and the release of enzymes during processing. experimental evidence of the involvement of the two 2[5h]-furanones, detected by a gas chromato ... | 2006 | 16957229 |
| mouse and human cell activation by n-dodecanoyl-dl-homoserine lactone, a chromobacterium violaceum autoinducer. | chromobacterium violaceum produces autoinducers, including homoserine lactones (hsls), for genetic regulation. among the seven hsls derived from c. violaceum we evaluated, only c(12)-hsl stimulated the production of inflammatory cytokines in mammalian monocytic cell lines through the activation of the nf-kappab signaling pathway besides their quorum-sensing role, like 3-oxo-c(12)-hsl from pseudomonas aeruginosa. | 2006 | 16982829 |
| mutations within the catalytic motif of dna adenine methyltransferase (dam) of aeromonas hydrophila cause the virulence of the dam-overproducing strain to revert to that of the wild-type phenotype. | in this study, we demonstrated that the methyltransferase activity associated with dam was essential for attenuation of aeromonas hydrophila virulence. we mutated aspartic acid and tyrosine residues to alanine within the conserved dppy catalytic motif of dam and transformed the pbad/damd/a, pbad/damy/a, and pbad/damahssu (with the native dam gene) recombinant plasmids into the escherichia coli gm33 (dam-deficient) strain. genomic dna (gdna) isolated from either of the e. coli gm33 strains harbor ... | 2006 | 16988254 |
| pip, a novel activator of phenazine biosynthesis in pseudomonas chlororaphis pcl1391. | secondary metabolites are important factors for interactions between bacteria and other organisms. pseudomonas chlororaphis pcl1391 produces the antifungal secondary metabolite phenazine-1-carboxamide (pcn) that inhibits growth of fusarium oxysporum f. sp. radius lycopersici the causative agent of tomato foot and root rot. our previous work unraveled a cascade of genes regulating the pcn biosynthesis operon, phzabcdefgh. via a genetic screen, we identify in this study a novel tetr/acrr regulator ... | 2006 | 16997957 |
| disruption of n-acyl homoserine lactone-mediated cell signaling and iron acquisition in epiphytic bacteria by leaf surface compounds. | since n-acyl homoserine lactones (ahls) are key mediators of cell density-dependent regulation of traits involved in virulence and epiphytic fitness in gram-negative bacteria such as pseudomonas syringae, a variety of plant species were examined to determine their production of leaf surface compounds that could interact with these signaling systems. leaf washings of 17 of 52 plant species tested stimulated or inhibited ahl-dependent traits in at least one of the bacterial reporter strains used. ... | 2006 | 16997987 |
| role of quorum sensing and antimicrobial component production by serratia plymuthica in formation of biofilms, including mixed biofilms with escherichia coli. | we have previously characterized the n-acyl-l-homoserine lactone-based quorum-sensing system of the biofilm isolate serratia plymuthica rvh1. here we investigated the role of quorum sensing and of quorum-sensing-dependent production of an antimicrobial compound (ac) on biofilm formation by rvh1 and on the cocultivation of rvh1 and escherichia coli in planktonic cultures or in biofilms. biofilm formation of s. plymuthica was not affected by the knockout of spli or splr, the s. plymuthica homologs ... | 2006 | 16997989 |
| chromobacterium violaceum: a case report of an unusual bacterium causing puerperal sepsis. | human infections by chromobacterium violaceum are rare. till date 6 cases have been reported from southern and eastern parts of india. we report here a case of puerperal sepsis by c. violaceum, probably the first case from eastern part of orissa. the patient was successfully treated with amikacin and gatifloxacin. | 2006 | 17001920 |
| two metallocarboxypeptidases from the protozoan trypanosoma cruzi belong to the m32 family, found so far only in prokaryotes. | mcps (metallocarboxypeptidases) of the m32 family of peptidases have been identified in a number of prokaryotic organisms, and only a few of them have been characterized biochemically. members of this family are absent from eukaryotic genomes, with the remarkable exception of those of trypanosomatids. the genome of the cl brener clone of trypanosoma cruzi, the causative agent of chagas' disease, encodes two such mcps, with 64% identity between them: tcmcp-1 and tcmcp-2. both genes, which are pre ... | 2007 | 17007610 |
| two metallocarboxypeptidases from the protozoan trypanosoma cruzi belong to the m32 family, found so far only in prokaryotes. | mcps (metallocarboxypeptidases) of the m32 family of peptidases have been identified in a number of prokaryotic organisms, and only a few of them have been characterized biochemically. members of this family are absent from eukaryotic genomes, with the remarkable exception of those of trypanosomatids. the genome of the cl brener clone of trypanosoma cruzi, the causative agent of chagas' disease, encodes two such mcps, with 64% identity between them: tcmcp-1 and tcmcp-2. both genes, which are pre ... | 2007 | 17007610 |
| antioxidant properties of violacein: possible relation on its biological function. | violacein, a violet pigment produced by chromobacterium violaceum, has attracted much attention in recent literature due to its pharmacological properties. in this work, the antioxidant properties of violacein were investigated. the reactivity with oxygen and nitrogen reactive species and 1,1-diphenyl-2-picryl-hydrazyl (dpph), a stable free radical, was evaluated. epr studies were carried out to evaluate the reactivity with the hydroxyl radical. the action of violacein against lipid peroxidation ... | 2006 | 17011197 |
| a plasmid-borne truncated luxi homolog controls quorum-sensing systems and extracellular carbohydrate production in methylobacterium extorquens am1. | a cryptic plasmid of methylobacterium extorquens am1 was found to encode tsli, a truncated luxi homolog. tsli was shown to be expressed and to control transcription of the acyl-homoserine lactone (hsl) synthase gene msai and thus, indirectly, acyl-hsl production. in addition, tsli was found to positively regulate extracellular polysaccharide production. | 2006 | 17015673 |
| occurrence of sep insecticidal toxin complex genes in serratia spp. and yersinia frederiksenii. | some strains of serratia entomophila and s. proteamaculans cause amber disease of the grass grub costelytra zealandica (coleoptera: scarabaeidae). three genes required for virulence, sepabc, are located on a large plasmid, padap. sequence analysis suggests that the sepabc gene cluster may be part of a horizontally mobile region. this study presents evidence for the putative mobility of the sep genes of padap. southern blot analysis showed that orthologues of the sep genes reside on plasmids with ... | 2006 | 17021209 |
| a homologue of the 3-oxoacyl-(acyl carrier protein) synthase iii gene located in the glycosylation island of pseudomonas syringae pv. tabaci regulates virulence factors via n-acyl homoserine lactone and fatty acid synthesis. | pseudomonas syringae pv. tabaci 6605 possesses a genetic region involved in flagellin glycosylation. this region is composed of three open reading frames: orf1, orf2, and orf3. our previous study revealed that orf1 and orf2 encode glycosyltransferases; on the other hand, orf3 has no role in posttranslational modification of flagellin. although the function of orf3 remained unclear, an orf3 deletion mutant (deltaorf3 mutant) had reduced virulence on tobacco plants. orf3 shows significant homology ... | 2006 | 17028280 |
| mutations in the yersinia pseudotuberculosis type iii secretion system needle protein, yscf, that specifically abrogate effector translocation into host cells. | the trafficking of effectors, termed yops, from yersinia spp. into host cells is a multistep process that requires the type iii secretion system (ttss). the ttss has three main structural parts: a base, a needle, and a translocon, which work together to ensure the polarized movement of yops directly from the bacterial cytosol into the host cell cytosol. to understand the interactions that take place at the interface between the tip of the ttss needle and the translocon, we developed a screen to ... | 2007 | 17071752 |
| mutations in the yersinia pseudotuberculosis type iii secretion system needle protein, yscf, that specifically abrogate effector translocation into host cells. | the trafficking of effectors, termed yops, from yersinia spp. into host cells is a multistep process that requires the type iii secretion system (ttss). the ttss has three main structural parts: a base, a needle, and a translocon, which work together to ensure the polarized movement of yops directly from the bacterial cytosol into the host cell cytosol. to understand the interactions that take place at the interface between the tip of the ttss needle and the translocon, we developed a screen to ... | 2007 | 17071752 |
| synthesis of n-acyl homoserine lactone analogues reveals strong activators of sdia, the salmonella enterica serovar typhimurium luxr homologue. | n-acyl homoserine lactones (ahls) are molecules that are synthesized and detected by many gram-negative bacteria to monitor the population density, a phenomenon known as quorum sensing. salmonella enterica serovar typhimurium is an exceptional species since it does not synthesize its own ahls, while it does encode a luxr homologue, sdia, which enables this bacterium to detect ahls that are produced by other species. to obtain more information about the specificity of the ligand binding by sdia, ... | 2007 | 17085703 |
| synthesis of n-acyl homoserine lactone analogues reveals strong activators of sdia, the salmonella enterica serovar typhimurium luxr homologue. | n-acyl homoserine lactones (ahls) are molecules that are synthesized and detected by many gram-negative bacteria to monitor the population density, a phenomenon known as quorum sensing. salmonella enterica serovar typhimurium is an exceptional species since it does not synthesize its own ahls, while it does encode a luxr homologue, sdia, which enables this bacterium to detect ahls that are produced by other species. to obtain more information about the specificity of the ligand binding by sdia, ... | 2007 | 17085703 |
| secondary metabolites help biocontrol strain pseudomonas fluorescens cha0 to escape protozoan grazing. | in soil ecosystems, bacteria must cope with predation activity, which is attributed mainly to protists. the development of antipredation strategies may help bacteria maintain higher populations and persist longer in the soil. we analyzed the interaction between the root-colonizing and biocontrol strain pseudomonas fluorescens cha0 and three different protist isolates (an amoeba, a flagellate, and a ciliate). cha0 produces a set of antibiotics, hcn, and an exoprotease. we observed that protists c ... | 2006 | 17088380 |
| production of antibacterial compounds and biofilm formation by roseobacter species are influenced by culture conditions. | bacterial communities associated with marine algae are often dominated by members of the roseobacter clade, and in the present study, we describe roseobacter phenotypes that may provide this group of bacteria with selective advantages when colonizing this niche. nine of 14 members of the roseobacter clade, of which half were isolated from cultures of the dinoflagellate pfiesteria piscicida, produced antibacterial compounds. many non-roseobacter marine bacteria were inhibited by sterile filtered ... | 2007 | 17098910 |
| production of antibacterial compounds and biofilm formation by roseobacter species are influenced by culture conditions. | bacterial communities associated with marine algae are often dominated by members of the roseobacter clade, and in the present study, we describe roseobacter phenotypes that may provide this group of bacteria with selective advantages when colonizing this niche. nine of 14 members of the roseobacter clade, of which half were isolated from cultures of the dinoflagellate pfiesteria piscicida, produced antibacterial compounds. many non-roseobacter marine bacteria were inhibited by sterile filtered ... | 2007 | 17098910 |
| cross-species gaca-controlled induction of antibiosis in pseudomonads. | signal extracts prepared from culture supernatants of pseudomonas fluorescens cha0 and pseudomonas aeruginosa pao stimulated gaca-dependent expression of small rnas and hence of antibiotic compounds in both hosts. pseudomonas corrugata lmg2172 and p. fluorescens sbw25 also produced signal molecules stimulating gaca-controlled antibiotic synthesis in strain cha0, illustrating a novel, n-acyl-homoserine lactone-independent type of interspecies communication. | 2007 | 17098922 |
| cross-species gaca-controlled induction of antibiosis in pseudomonads. | signal extracts prepared from culture supernatants of pseudomonas fluorescens cha0 and pseudomonas aeruginosa pao stimulated gaca-dependent expression of small rnas and hence of antibiotic compounds in both hosts. pseudomonas corrugata lmg2172 and p. fluorescens sbw25 also produced signal molecules stimulating gaca-controlled antibiotic synthesis in strain cha0, illustrating a novel, n-acyl-homoserine lactone-independent type of interspecies communication. | 2007 | 17098922 |
| microevolution of cytochrome bd oxidase in staphylococci and its implication in resistance to respiratory toxins released by pseudomonas. | pseudomonas aeruginosa and staphylococcus aureus are opportunistic pathogens and frequently coinfect the lungs of cystic fibrosis patients. p. aeruginosa secretes an arsenal of small respiratory inhibitors, like pyocyanin, hydrogen cyanide, or quinoline n-oxides, that may act against the commensal flora as well as host cells. here, we show that with respect to their susceptibility to these respiratory inhibitors, staphylococcal species can be divided into two groups: the sensitive group, compris ... | 2006 | 17108291 |