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phenotypic and molecular characterisation of fish-borne flavobacterium johnsoniae-like isolates from aquaculture systems in south africa.fish infections caused by pathogenic flavobacterium species are a major problem in the aquaculture industry worldwide, often leading to large economic losses. thirty-two flavobacterium spp. isolates, obtained from various diseased fish species and biofilm growth, were characterised genetically using 16s rdna pcr restriction fragment length polymorphism (rflp), randomly amplified polymorphic dna (rapd) pcr, repetitive extragenic palindromic (rep) element pcr, plasmid profiling, whole cell protein ...200717113757
isolation and characterization of hydrogen-oxidizing bacteria induced following exposure of soil to hydrogen gas and their impact on plant growth.in many legumes, the nitrogen fixing root nodules produce h2 gas that diffuses into soil. it has been demonstrated that such exposure of soil to h2 can promote plant growth. to assess whether this may be due to h2-oxidizing microorganisms, bacteria were isolated from soil treated with h2 under laboratory conditions and from soils collected adjacent to h2 producing soybean nodules. nineteen isolates of h2-oxidizing bacteria were obtained and all exhibited a half-saturation coefficient (ks) for h2 ...200717222141
flavobacterium defluvii sp. nov., isolated from activated sludge.a gram-negative bacterium, designated strain emb117t, was isolated from a municipal wastewater treatment plant and characterized by polyphasic taxonomy. the cells were non-spore-forming rods that showed gliding motility. optimal growth occurred at 25-30 degrees c and ph 7.0-8.0. strain emb117t contained phosphatidylethanolamine as the predominant polar lipid, and the major fatty acids were iso-c(15 : 0), iso-c(17 : 0) 3-oh, iso-c(15 : 0) 3-oh and summed feature 3 (c(16 : 1)omega7c and/or iso-c(1 ...200717267956
genome sequence of the cellulolytic gliding bacterium cytophaga hutchinsonii.the complete dna sequence of the aerobic cellulolytic soil bacterium cytophaga hutchinsonii, which belongs to the phylum bacteroidetes, is presented. the genome consists of a single, circular, 4.43-mb chromosome containing 3,790 open reading frames, 1,986 of which have been assigned a tentative function. two of the most striking characteristics of c. hutchinsonii are its rapid gliding motility over surfaces and its contact-dependent digestion of crystalline cellulose. the mechanism of c. hutchin ...200717400776
evaluation of adherence, hydrophobicity, aggregation, and biofilm development of flavobacterium johnsoniae-like isolates.flavobacterium spp. isolates have been identified in diverse biofilm structures, but the mechanism of adherence has not been elucidated. the absence of conventional biofilm-associated structures such as fimbriae, pili, and flagella suggest that surface hydrophobicity, and/or autoaggregation and coaggregation may play an important role in adherence and biofilm formation. the biofilm-forming capacity of 29 flavobacterium johnsoniae-like isolates obtained from south african aquaculture systems was ...200817401596
mutational analysis of the ompa promoter from flavobacterium johnsoniae.sequences that mediate the initiation of transcription in flavobacterium species are not well known. the majority of identified flavobacterium promoter elements show homology to those of other members of the phylum bacteroidetes, but not of proteobacteria, and they function poorly in escherichia coli. in order to analyze the flavobacterium promoter structure systematically, we investigated the -33 consensus element, -7 consensus element, and spacer length of the flavobacterium ompa promoter by m ...200717483221
flavobacterium johnsoniae spra is a cell surface protein involved in gliding motility.flavobacterium johnsoniae cells glide rapidly over surfaces by an unknown mechanism. transposon-induced spra mutants formed nonspreading colonies on agar, and the cells examined in wet mounts were deficient in attachment to surfaces and were almost completely nonmotile. exposure of intact cells to proteinase k cleaved the 270-kda spra into several large peptides, suggesting that it is partially exposed on the cell surface.200717644580
cell surface filaments of the gliding bacterium flavobacterium johnsoniae revealed by cryo-electron tomography.flavobacterium johnsoniae cells glide rapidly over surfaces by an as-yet-unknown mechanism. using cryo-electron tomography, we show that wild-type cells display tufts of approximately 5-nm-wide cell surface filaments that appear to be anchored to the inner surface of the outer membrane. these filaments are absent in cells of a nonmotile gldf mutant but are restored upon expression of plasmid-encoded gldf, a component of a putative atp-binding cassette transporter.200717693495
flavobacterium ceti sp. nov., isolated from beaked whales (ziphius cavirostris).three isolates of a gram-negative, catalase- and oxidase-positive, rod-shaped bacterium, isolated from the lung and liver of two beaked whales, were characterized by phenotypic and molecular genetic methods. based on cellular morphology and biochemical criteria, the isolates were tentatively assigned to the family flavobacteriaceae, although they did not appear to correspond to any recognized species. comparative 16s rrna gene sequencing showed that the three new isolates shared 100% sequence si ...200717978226
sprb is a cell surface component of the flavobacterium johnsoniae gliding motility machinery.cells of the gliding bacterium flavobacterium johnsoniae move rapidly over surfaces by an unknown mechanism. transposon insertions in sprb resulted in cells that were defective in gliding. sprb is a highly repetitive 669-kda cell surface protein, and antibodies against sprb inhibited the motility of wild-type cells. polystyrene microspheres coated with antibodies against sprb attached to and were rapidly propelled along the cell surface, suggesting that sprb is one of the outermost components of ...200818281397
use of suppressive subtractive hybridization to identify flavobacterium columnare dna sequences not shared with flavobacterium johnsoniae.to identify specific sequences in the fish pathogen flavobacterium columnare not shared by flavobacterium johnsoniae.200818444979
identification of a multidrug efflux pump in flavobacterium johnsoniae.in this study, the mechanism conferring multiple drug resistance in several strains of flavobacteria isolated from the ovarian fluids of hatchery reared 3-year old brook trout salvelinus fontinalis was investigated. metabolic fingerprinting and 16s rrna gene sequences identified the isolates as flavobacterium johnsoniae. the isolates exhibited multiple resistances to a wide range of antimicrobial classes including penicillin, cephem, monobactam, aminoglycoside, and phenicol. although plasmids an ...200919558960
novel features of the polysaccharide-digesting gliding bacterium flavobacterium johnsoniae as revealed by genome sequence analysis.the 6.10-mb genome sequence of the aerobic chitin-digesting gliding bacterium flavobacterium johnsoniae (phylum bacteroidetes) is presented. f. johnsoniae is a model organism for studies of bacteroidete gliding motility, gene regulation, and biochemistry. the mechanism of f. johnsoniae gliding is novel, and genome analysis confirms that it does not involve well-studied motility organelles, such as flagella or type iv pili. the motility machinery is composed of gld proteins in the cell envelope t ...200919717629
utilization of oligo- and polysaccharides at microgram-per-litre levels in freshwater by flavobacterium johnsoniae.to obtain a bacterial strain that can be used to quantify biodegradable polysaccharides at concentrations of a few micrograms per litre in freshwater.201019804538
a protein secretion system linked to bacteroidete gliding motility and pathogenesis.porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. protein secretion systems common to other gram-negative bacteria are lacking in p. gingivalis, but several proteins, including port, have been linked to gingipain secretion. comparative genome analysis and genetic experiments revealed 11 additional proteins involved in gingipain secretion. six of these (pork, porl, porm, porn, porw, and sov) were similar in sequence to flavobacte ...201019966289
flavobacterium johnsoniae gldn and gldo are partially redundant genes required for gliding motility and surface localization of sprb.cells of the gliding bacterium flavobacterium johnsoniae move rapidly over surfaces. mutations in gldn cause a partial defect in gliding. a novel bacteriophage selection strategy was used to aid construction of a strain with a deletion spanning gldn and the closely related gene gldo in an otherwise wild-type f. johnsoniae uw101 background. bacteriophage transduction was used to move a gldn mutation into f. johnsoniae uw101 to allow phenotypic comparison with the gldno deletion mutant. cells of t ...201020038590
spreading versus biomass production by colonies of the fish pathogen flavobacterium psychrophilum: role of the nutrient concentration.colonies of the fish pathogen flavobacterium psychrophilum have gliding motility in media with low agar concentrations. although gliding motility, particularly in flavobacterium johnsoniae, has been well-studied, little is known about its regulation by environmental factors. the work described here shows that the ability of f. psychrophilum to spread over surfaces depends on nutrient availability. in fact, as the nutrient contents of the medium decreased, spreading was favored and the diameter o ...200920112225
development of an efficient expression system for flavobacterium strains.strong promoters were isolated from flavobacterium johnsoniae in a promoter-trap vector incorporating a gfp reporter system, and were used to express fluorescent protein markers (including gfp, yfp, morange and mstrawberry) and insecticidal protein genes in flavobacterium strains. sequence analysis of trapped dna fragments showed conserved bacteroidetes promoter motifs (ttg-n(19)-tanntttg) located upstream of putative open reading frames. plasmids harboring these genomic dna fragments from f. jo ...201020206244
studies on nonfruiting myxobacteria; cytophaga johnsonae, n. sp., a chitindecomposing myxobacterium. 194720290967
microbial strengthening of loose sand.to test whether the addition of flavobacterium johnsoniae could increase the strength of saturated ottawa 30 sand.201020557452
flavobacterium ginsenosidimutans sp. nov., a bacterium with ginsenoside converting activity isolated from soil of a ginseng field.a gram-negative, aerobic, non-motile, non-spore-forming, yellow-pigmented, rod-shaped bacterium, designated strain thg 01(t), was isolated from the soil of a ginseng field in pocheon province, south korea, and its taxonomic position was investigated by using a polyphasic approach. strain thg 01(t) grew well at 25-37 °c and ph 6.0-7.5 in the absence of nacl on nutrient agar. on the basis of 16s rrna gene sequence similarity data, strain thg 01(t) was shown to belong to the family flavobacteriacea ...201020601491
flavobacterium johnsoniae sprb is part of an operon spanning the additional gliding motility genes sprc, sprd, and sprf.cells of flavobacterium johnsoniae move rapidly over surfaces by a process known as gliding motility. gld proteins are thought to comprise the gliding motor that propels cell surface adhesins, such as the 669-kda sprb. a novel protein secretion apparatus called the por secretion system (porss) is required for assembly of sprb on the cell surface. genetic and molecular analyses revealed that sprb is part of a seven-gene operon spanning 29.3 kbp of dna. in addition to sprb, three other genes of th ...201021131497
flavobacterium chungbukense sp. nov., isolated from soil.a yellow-pigmented, gram-staining-negative, non-motile, strictly aerobic and rod-shaped bacterium, designated cs100t, was isolated from soil in chungbuk, korea. phylogenetic analysis and comparative studies based on the 16s rrna gene sequence showed that strain cs100t belonged to the genus flavobacterium in the family flavobacteriaceae. strain cs100t showed the highest sequence similarities to f. glaciei jcm 13953t (97.6%) and f. johnsoniae kacc 11410t (97.1%). sequence similarity to other membe ...201021186289
development and use of a gene deletion strategy for flavobacterium johnsoniae to identify the redundant gliding motility genes remf, remg, remh, and remi.cells of flavobacterium johnsoniae exhibit rapid gliding motility over surfaces. cell movement is thought to involve motor complexes comprised of gld proteins that propel the cell surface adhesin sprb. the four distal genes of the sprb operon (sprc, sprd, sprb, and sprf) are required for normal motility and for formation of spreading colonies, but the roles of the remaining three genes (remf, remg, and fjoh_0982) are unclear. a gene deletion strategy was developed to determine whether these gene ...201121421754
mutations in flavobacterium johnsoniae spre result in defects in gliding motility and protein secretion.cells of the gliding bacterium flavobacterium johnsoniae move rapidly over surfaces. transposon mutagenesis was used to identify spre, which is involved in gliding. mutations in spre resulted in the formation of nonspreading colonies on agar. spre mutant cells in wet mounts were almost completely deficient in attachment to and movement on glass, but a small percentage of cells exhibited slight movements, indicating that the motility machinery was not completely disrupted. spre is a predicted lip ...201121784937
flavobacterium johnsoniae as model organism for characterizing biopolymer utilization in oligotrophic freshwater environments.biopolymers are important substrates for heterotrophic bacteria in oligotrophic freshwater environments, but information on bacterial growth kinetics with biopolymers is scarce. the objective of this study was to characterize bacterial biopolymer utilization in these environments by assessing the growth kinetics of flavobacterium johnsoniae strain a3, which is specialized in utilizing biopolymers at µg l(-1) levels. growth of strain a3 with amylopectin, xyloglucan, gelatin, maltose, or fructose ...201121803894
flavobacterium compostarboris sp. nov., isolated from leaf-and-branch compost and emended descriptions of flavobacterium hercynium, flavobacterium resistens and flavobacterium johnsoniae.a strictly aerobic, gram-staining-negative, yellow-pigmented, non-spore forming, rod-shaped bacterium, designated strain 15c3(t), was isolated from aerobic leaf-and-branch compost at expo park in osaka, japan. growth was observed at 9-33 °c (optimum, 25 °c) and ph 5.6-7.9 (optimum, ph 6.1-7.0). no growth occurred in the presence of > 2 % (w/v) nacl. strain 15c3(t) reduced nitrate to nitrogen and showed catalase activity but no oxidase activity. the predominant fatty acids were iso-c(15:0), iso-c ...201122021577
the volatile-producing flavobacterium johnsoniae strain gse09 shows biocontrol activity against phytophthora capsici in pepper.previously, we selected a bacterial strain (gse09) antagonistic to phytophthora capsici on pepper, which produced a volatile compound (2,4-di-tert-butylphenol), inhibiting the pathogen. in this study, we identified strain gse09 and characterized some of the biological traits of this strain in relation to its antagonistic properties against p. capsici. in addition, we examined bacterial colonization on the root surface or in rhizosphere soil and the effect of various concentrations of the volatil ...201222563881
flavobacterium johnsoniae rema is a mobile cell surface lectin involved in gliding.cells of flavobacterium johnsoniae move rapidly over surfaces by a process known as gliding motility. gld proteins are thought to comprise the motor that propels the cell surface adhesin sprb. cells with mutations in sprb are partially defective in motility and are also resistant to some bacteriophages. transposon mutagenesis of a strain carrying a deletion spanning sprb identified eight mutants that were resistant to additional phages and exhibited reduced motility. four of the mutants had tran ...201222582276
flavobacterium tilapiae sp. nov., isolated from a freshwater pond, and emended descriptions of flavobacterium defluvii and flavobacterium johnsoniae.a bacterial strain, designated ruye-71(t), was isolated from a freshwater tilapiine cichlid fish culture pond in taiwan and characterized in a taxonomic study using a polyphasic approach. cells of strain ruye-71(t) were gram-stain-negative, strictly aerobic, yellow-pigmented rods that were motile by gliding. growth occurred at 10-30 °c (optimum, 15-30 °c), at ph 7.0-8.0 (optimum, ph 8.0) and with 0-2 % nacl (optimum, 0-1 %). phylogenetic analyses based on 16s rrna gene sequences showed that stra ...201322611198
the mercury resistance (mer) operon in a marine gliding flavobacterium, tenacibaculum discolor 9a5.genes conferring mercury resistance have been investigated in a variety of bacteria and archaea but not in bacteria of the phylum bacteroidetes, despite their importance in many environments. we found, however, that a marine gliding bacteroidetes species, tenacibaculum discolor, was the predominant mercury-resistant bacterial taxon cultured from a salt marsh fertilized with mercury-contaminated sewage sludge. here we report characterization of the mercuric reductase and the narrow-spectrum mercu ...201322816663
gliding motility and por secretion system genes are widespread among members of the phylum bacteroidetes.the phylum bacteroidetes is large and diverse, with rapid gliding motility and the ability to digest macromolecules associated with many genera and species. recently, a novel protein secretion system, the por secretion system (porss), was identified in two members of the phylum, the gliding bacterium flavobacterium johnsoniae and the nonmotile oral pathogen porphyromonas gingivalis. the components of the porss are not similar in sequence to those of other well-studied bacterial secretion systems ...201323123910
molecular characterization of a cold-active recombinant xylanase from flavobacterium johnsoniae and its applicability in xylan hydrolysis.a novel xylanase gene, xyn10a, was cloned from flavobacterium johsoniae, overexpressed in a flavobacterial expression system, the recombinant enzyme purified by ni-affinity chromatography, and enzyme structure and activity analyzed. xyn10a was found to be a modular xylanase with an fn3 accessory domain on its n-terminal and a catalytic region on the c-terminal. the optimum ph and temperature for xyn10a was 8.0 and 30 °c, but xyn10a retained 50% activity at 4 °c, indicating that xyn10a is a cold- ...201223196234
identification and characterization of cellobiose 2-epimerases from various aerobes.cellobiose 2-epimerase (ce), found mainly in anaerobes, reversibly converts d-glucose residues at the reducing end of β-1,4-linked oligosaccharides to d-mannose residues. in this study, we characterized ce-like proteins from various aerobes (flavobacterium johnsoniae nbrc 14942, pedobacter heparinus nbrc 12017, dyadobacter fermentans atcc 700827, herpetosiphon aurantiacus atcc 23779, saccharophagus degradans atcc 43961, spirosoma linguale atcc 33905, and teredinibacter turnerae atcc 39867), beca ...201323291764
changes of bacterioplankton apparent species richness in two ornamental fish aquaria.we analysed the 16s rrna gene diversity within the bacterioplankton community in the water column of the ornamental fish pterophyllum scalare and archocentrus nigrofasciatus aquaria during a 60-day growth experiment in order to detect any dominant bacterial species and their possible association with the rearing organisms. the basic physical and chemical parameters remained stable but the bacterial community at 0, 30 and 60 days showed marked differences in bacterial cell abundance and diversity ...201323519098
flavobacterium johnsoniae gldk, gldl, gldm, and spra are required for secretion of the cell surface gliding motility adhesins sprb and rema.flavobacterium johnsoniae cells move rapidly over surfaces by gliding motility. gliding results from the movement of adhesins such as sprb and rema along the cell surface. these adhesins are delivered to the cell surface by a bacteroidetes-specific secretion system referred to as the type ix secretion system (t9ss). gldn, spre, sprf, and sprt are involved in secretion by this system. here we demonstrate that gldk, gldl, gldm, and spra are each also involved in secretion. nonpolar deletions of gl ...201323667240
enzymatic biotransformation of ginsenoside rb1 and gypenoside xvii into ginsenosides rd and f2 by recombinant β-glucosidase from flavobacterium johnsoniae.this study focused on the enzymatic biotransformation of the major ginsenoside rb1 into rd for the mass production of minor ginsenosides using a novel recombinant β-glucosidase from flavobacterium johnsoniae. the gene (bglf3) consisting of 2,235 bp (744 amino acid residues) was cloned and the recombinant enzyme overexpressed in escherichia coli bl21(de3) was characterized. this enzyme could transform ginsenoside rb1 and gypenoside xvii to the ginsenosides rd and f2, respectively. the glutathione ...201223717145
helical flow of surface protein required for bacterial gliding motility.cells of flavobacterium johnsoniae and of many other members of the phylum bacteroidetes exhibit rapid gliding motility over surfaces by a unique mechanism. these cells do not have flagella or pili; instead, they rely on a novel motility apparatus composed of gld and spr proteins. sprb, a 669-kda cell-surface adhesin, is required for efficient gliding. sprb was visualized by electron microscopy as thin 150-nm-long filaments extending from the cell surface. fluorescence microscopy revealed moveme ...201323781102
raman spectrometric discrimination of flexirubin pigments from two genera of bacteroidetes.flexirubins are specific polyene pigments produced by several genera of bacteroidetes. colonies and cell extracts of flavobacterium johnsoniae and flexibacter elegans have been investigated by raman spectroscopy to show that this fast and non-destructive technique can be used to differentiate these pigments from carotenoids and to compare the flexirubin content of the two microorganisms. the presence or absence of certain distinguishing features in the ch combination band region at 2500-2750 cm( ...201324033756
isolation and identification of phytate-degrading bacteria and their contribution to phytate mineralization in soil.to better understand the phosphorus (p) cycling in an agricultural soil environment, amounts of total, organic and inorganic p in 10 agricultural soil samples were analyzed. since a large proportion (57.8%) of the total p in the soils was in organic form, a method was developed to evaluate the mineralization rate of organic p in the soil by adding phytate to the soil and analyzing the change in water-soluble p (wsp) content after incubating it for 3 days. moreover, the relationship between the p ...201324201147
epilactose production by 2 cellobiose 2-epimerases in natural milk.it was reported recently that cellobiose 2-epimerases (ce) from various aerobic microorganisms convert lactose to epilactose in defined buffer systems. in this study, we showed that ce from 2 mesophilic microorganisms, flavobacterium johnsoniae and pedobacter heparinus, were capable of converting lactose to prebiotic epilactose not only in buffer but also in a complex milk system. first, the 2 enzymes were separately cloned, recombinantly expressed in escherichia coli, and purified by column chr ...201424210487
deletion of the cytophaga hutchinsonii type ix secretion system gene sprp results in defects in gliding motility and cellulose utilization.cytophaga hutchinsonii glides rapidly over surfaces and employs a novel collection of cell-associated proteins to digest crystalline cellulose. himarem1 transposon mutagenesis was used to isolate a mutant with an insertion in chu_0170 (sprp) that was partially deficient in gliding motility and was unable to digest filter paper cellulose. sprp is similar in sequence to the porphyromonas gingivalis type ix secretion system (t9ss) protein porp that is involved in the secretion of gingipain protease ...201424257839
flavobacterium johnsoniae chitinase chia is required for chitin utilization and is secreted by the type ix secretion system.flavobacterium johnsoniae, a member of phylum bacteriodetes, is a gliding bacterium that digests insoluble chitin and many other polysaccharides. a novel protein secretion system, the type ix secretion system (t9ss), is required for gliding motility and for chitin utilization. five potential chitinases were identified by genome analysis. fjoh_4555 (chia), a 168.9-kda protein with two glycoside hydrolase family 18 (gh18) domains, was targeted for analysis. disruption of chia by insertional mutage ...201424363341
bidirectional bacterial gliding motility powered by the collective transport of cell surface proteins.the gliding motility of flavobacterium johnsoniae is driven by moving surface adhesive proteins. recently, these motility components were observed to travel along a closed loop on the cell surface. the mechanism by which such moving surface adhesins give rise to cell motion remains unknown. on the basis of the unique motility properties of f. johnsoniae, we present a generic model for bidirectional motion of rigidly coupled adhesins, which are propelled in opposite directions. using analytical a ...201324483703
bacteria that glide with helical tracks.many bacteria glide smoothly on surfaces, despite having no discernable propulsive organelles on their surface. recent experiments with myxococcus xanthus and flavobacterium johnsoniae show that both of these distantly related bacterial species glide using proteins that move in helical tracks, albeit with significantly different motility mechanisms. both species utilize proton-motive force for movement. although the motors that power gliding in m. xanthus have been identified, the f. johnsoniae ...201424556443
discovery of a bifunctional acyltransferase responsible for ornithine lipid synthesis in serratia proteamaculans.ornithine lipids (ols) are phosphorus-free membrane lipids that can be formed by many bacteria but that are absent from archaea and eukaryotes. a function for ols in stress conditions and in host-bacteria interactions has been shown in some bacteria. some bacterial species have been described that can form ols, but lack the known genes (olsba) involved in its biosynthesis, which implied the existence of a second pathway. here we describe the bifunctional protein olsf from serratia proteamaculans ...201525040623
flavobacterium johnsoniae porv is required for secretion of a subset of proteins targeted to the type ix secretion system.flavobacterium johnsoniae exhibits gliding motility and digests many polysaccharides, including chitin. a novel protein secretion system, the type ix secretion system (t9ss), is required for gliding and chitin utilization. the t9ss secretes the cell surface motility adhesins sprb and rema and the chitinase chia. proteins involved in secretion by the t9ss include gldk, gldl, gldm, gldn, spra, spre, and sprt. porphyromonas gingivalis has orthologs for each of these that are required for secretion ...201525331433
a rotary motor drives flavobacterium gliding.cells of flavobacterium johnsoniae, a rod-shaped bacterium devoid of pili or flagella, glide over glass at speeds of 2-4 μm/s [1]. gliding is powered by a protonmotive force [2], but the machinery required for this motion is not known. usually, cells move along straight paths, but sometimes they exhibit a reciprocal motion, attach near one pole and flip end over end, or rotate. this behavior is similar to that of a cytophaga species described earlier [3]. development of genetic tools for f. john ...201525619763
highly active and specific tyrosine ammonia-lyases from diverse origins enable enhanced production of aromatic compounds in bacteria and saccharomyces cerevisiae.phenylalanine and tyrosine ammonia-lyases form cinnamic acid and p-coumaric acid, which are precursors of a wide range of aromatic compounds of biotechnological interest. lack of highly active and specific tyrosine ammonia-lyases has previously been a limitation in metabolic engineering approaches. we therefore identified 22 sequences in silico using synteny information and aiming for sequence divergence. we performed a comparative in vivo study, expressing the genes intracellularly in bacteria ...201525911487
lysine and novel hydroxylysine lipids in soil bacteria: amino acid membrane lipid response to temperature and ph in pseudopedobacter saltans.microbial decomposition of organic matter is an essential process in the global carbon cycle. the soil bacteria pseudopedobacter saltans and flavobacterium johnsoniae are both able to degrade complex organic molecules, but it is not fully known how their membrane structures are adapted to their environmental niche. the membrane lipids of these species were extracted and analyzed using high performance liquid chromatography-electrospray ionization/ion trap/mass spectrometry (hplc-esi/it/ms) and h ...201526175720
[construction and application of bioinformatic analysis platform for aquatic pathogen based on the milkyway-2 supercomputer].as a key component of life science, bioinformatics has been widely applied in genomics, transcriptomics, and proteomics. however, the requirement of high-performance computers rather than common personal computers for constructing a bioinformatics platform significantly limited the application of bioinformatics in aquatic science. in this study, we constructed a bioinformatic analysis platform for aquatic pathogen based on the milkyway-2 supercomputer. the platform consisted of three functional ...201526351170
improved biostability assessment of drinking water with a suite of test methods at a water supply treating eutrophic lake water.assessment of drinking-water biostability is generally based on measuring bacterial growth in short-term batch tests. however, microbial growth in the distribution system is affected by multiple interactions between water, biofilms and sediments. therefore a diversity of test methods was applied to characterize the biostability of drinking water distributed without disinfectant residual at a surface-water supply. this drinking water complied with the standards for the heterotrophic plate count a ...201526451977
flavobacterium gliding motility and the type ix secretion system.cells of flavobacterium johnsoniae crawl rapidly over surfaces in a process called gliding motility. these cells do not have flagella or pili but instead rely on a novel motility machine composed of proteins that are unique to the phylum bacteroidetes. the motility adhesins sprb and rema are propelled along the cell surface by the still poorly-defined gliding motor. interaction of these adhesins with a surface results in translocation of the cell. sprb and rema are delivered to the cell surface ...201526461123
towards a model for flavobacterium gliding.cells of flavobacterium johnsoniae, a rod-shaped bacterium about 6 μm long, do not have flagella or pili, yet they move over surfaces at speeds of about 2 μm/s. this motion is called gliding. recent advances in f. johnsoniae research include the discovery of mobile cell-surface adhesins and rotary motors. the puzzle is how rotary motion leads to linear motion. we suggest a possible mechanism, inspired by the snowmobile.201526476806
involvement of the type ix secretion system in capnocytophaga ochracea gliding motility and biofilm formation.capnocytophaga ochracea is a gram-negative, rod-shaped bacterium that demonstrates gliding motility when cultured on solid agar surfaces. c. ochracea possesses the ability to form biofilms; however, factors involved in biofilm formation by this bacterium are unclear. a type ix secretion system (t9ss) in flavobacterium johnsoniae was shown to be involved in the transport of proteins (e.g., several adhesins) to the cell surface. genes orthologous to those encoding t9ss proteins in f. johnsoniae ha ...201626729712
comparative analysis of cellulophaga algicola and flavobacterium johnsoniae gliding motility.gliding motility is common in members of the phylum bacteroidetes, including flavobacterium johnsoniae and cellulophaga algicola. f. johnsoniae gliding has been extensively studied and involves rapid movement of the cell surface adhesin sprb. genetic analysis of c. algicola allowed a comparative analysis of gliding. sixty-three himarem1-induced mutants that formed nonspreading colonies were characterized. each had an insertion in an ortholog of an f. johnsoniae motility gene, highlighting simila ...201627044627
a glycoside hydrolase family 31 dextranase with high transglucosylation activity from flavobacterium johnsoniae.glycoside hydrolase family (gh) 31 enzymes exhibit various substrate specificities, although the majority of members are α-glucosidases. here, we constructed a heterologous expression system of a gh31 enzyme, fjoh_4430, from flavobacterium johnsoniae nbrc 14942, using escherichia coli, and characterized its enzymatic properties. the enzyme hydrolyzed dextran and pullulan to produce isomaltooligosaccharides and isopanose, respectively. when isomaltose was used as a substrate, the enzyme catalyzed ...201627170214
the screw-like movement of a gliding bacterium is powered by spiral motion of cell-surface adhesins.flavobacterium johnsoniae, a rod-shaped bacterium, glides over surfaces at speeds of ∼2 μm/s. the propulsion of a cell-surface adhesin, sprb, is known to enable gliding. we used cephalexin to generate elongated cells with irregular shapes and followed their displacement in three dimensions. these cells rolled about their long axes as they moved forward, following a right-handed trajectory. we coated gold nanoparticles with an sprb antibody and tracked them in three dimensions in an evanescent fi ...201627602728
identification of a new lipoprotein export signal in gram-negative bacteria.bacteria of the phylum bacteroidetes, including commensal organisms and opportunistic pathogens, harbor abundant surface-exposed multiprotein membrane complexes (sus-like systems) involved in carbohydrate acquisition. these complexes have been mostly linked to commensalism, and in some instances, they have also been shown to play a role in pathogenesis. sus-like systems are mainly composed of lipoproteins anchored to the outer membrane and facing the external milieu. this lipoprotein localizatio ...201627795390
exploiting members of the bahd acyltransferase family to synthesize multiple hydroxycinnamate and benzoate conjugates in yeast.bahd acyltransferases, named after the first four biochemically characterized enzymes of the group, are plant-specific enzymes that catalyze the transfer of coenzyme a-activated donors onto various acceptor molecules. they are responsible for the synthesis in plants of a myriad of secondary metabolites, some of which are beneficial for humans either as therapeutics or as specialty chemicals such as flavors and fragrances. the production of pharmaceutical, nutraceutical and commodity chemicals us ...201627871334
a polysaccharide utilization locus from flavobacterium johnsoniae enables conversion of recalcitrant chitin.chitin is the second most abundant polysaccharide on earth and as such a great target for bioconversion applications. the phylum bacteroidetes is one of nature's most ubiquitous bacterial lineages and is essential in the global carbon cycle with many members being highly efficient degraders of complex carbohydrates. however, despite their specialist reputation in carbohydrate conversion, mechanisms for degrading recalcitrant crystalline polysaccharides such as chitin and cellulose are hitherto u ...201627933102
draft genome sequence of flavobacterium johnsoniae ci04, an isolate from the soybean rhizosphere.flavobacterium johnsoniae ci04 was coisolated with bacillus cereus from a root of a field-grown soybean plant in arlington, wi, and selected as a model for studying commensalism between members of the cytophaga-flavobacterium-bacteroides group and b. cereus here we report the draft genome sequence of f. johnsoniae ci04 obtained by illumina sequencing.201728126949
developmental trajectories of amphibian microbiota: response to bacterial therapy depends on initial community structure.improving host health through microbial manipulation requires untangling factors that shape the microbiome. there is currently little understanding of how initial community structure may drive the microbiota trajectory across host development or influence bacterial therapy outcomes. probiotic baths of surface symbionts, pseudomonas fluorescens and flavobacterium johnsoniae were administered to 240 tadpoles of the midwife toad, alytes obstetricans in semi-natural outdoor mesocosms originating fro ...201728229543
diverse c-terminal sequences involved in flavobacterium johnsoniae protein secretion.flavobacteriumjohnsoniae and many related bacteria secrete proteins across the outer membrane using the type ix secretion system (t9ss). proteins secreted by t9sss have amino-terminal signal peptides for export across the cytoplasmic membrane by the sec system and carboxy-terminal domains (ctds) targeting them for secretion across the outer membrane by the t9ss. most but not all t9ss ctds belong to the family tigr04183 (type a ctds). we functionally characterized diverse ctds for secretion by th ...201728396348
identification of enzymes involved in the mevalonate pathway of flavobacterium johnsoniae.the mevalonate pathway is prevalent in eukaryotes, archaea, and a limited number of bacteria. this pathway yields the fundamental precursors for isoprenoid biosynthesis, i.e., isopentenyl diphosphate and dimethylally diphosphate. in the downstream part of the general eukaryote-type mevalonate pathway, mevalonate is converted into isopentenyl diphosphate by the sequential actions of mevalonate kinase, phosphomevalonate kinase, and diphosphomevalonte decarboxylase, while a partial lack of the puta ...201728442346
the type ix secretion system (t9ss): highlights and recent insights into its structure and function.protein secretion systems are vital for prokaryotic life, as they enable bacteria to acquire nutrients, communicate with other species, defend against biological and chemical agents, and facilitate disease through the delivery of virulence factors. in this review, we will focus on the recently discovered type ix secretion system (t9ss), a complex translocon found only in some species of the bacteroidetes phylum. t9ss plays two roles, depending on the lifestyle of the bacteria. it provides either ...201728603700
untangling flavobacterium johnsoniae gliding motility and protein secretion.flavobacterium johnsoniae exhibits rapid gliding motility over surfaces. at least 20 genes are involved in this process. seven of these, gldk, gldl, gldm, gldn, spra, spre, and sprt, encode proteins of the type ix protein secretion system (t9ss). the t9ss is required for surface localization of the motility adhesins sprb and rema, and for secretion of the soluble chitinase chia. here, we demonstrate that the gliding motility proteins glda, gldb, gldd, gldf, gldh, gldi, and gldj are also essentia ...201829109184
more than gliding: involvement of gldd and gldg in the virulence of flavobacterium psychrophilum.a fascinating characteristic of most members of the genus flavobacterium is their ability to move over surfaces by gliding motility. flavobacterium psychrophilum, an important pathogen of farmed salmonids worldwide, contains in its genome the 19 gld and spr genes shown to be required for gliding or spreading in flavobacterium johnsoniae; however, their relative role in its lifestyle remains unknown. in order to address this issue, two spreading deficient mutants were produced as part of a tn4351 ...201729163446
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