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phylogenetic diversity of the intestinal bacterial community in the termite reticulitermes speratus.the phylogenetic diversity of the intestinal microflora of a lower termite, reticulitermes speratus, was examined by a strategy which does not rely on cultivation of the resident microorganisms. small-subunit rrna genes (16s rdnas) were directly amplified from the mixed-population dna of the termite gut by the pcr and were clonally isolated. analysis of partial 16s rdna sequences showed the existence of well-characterized genera as well as the presence of bacterial species for which no 16s rdna ...19968593049
site of secretion and properties of endogenous endo-beta-1,4-glucanase components from reticulitermes speratus (kolbe), a japanese subterranean termite.two endo-beta-1,4-glucanase components (yeg1 and yeg2) of the endogenous cellulase from the japanese subterranean termite, reticulitermes speratus, were purified to homogeneity using gel filtration and hydroxylapatite chromatography, and their enzymatic properties were investigated. using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (sds-page), yeg1 and yeg2 had m(r) of 42 kda and 41 kda, respectively. both components had an optimal ph of 6.0, an optimal temperature of 50 degrees c ...19979134711
molecular phylogenetic identification of the intestinal anaerobic microbial community in the hindgut of the termite, reticulitermes speratus, without cultivation.a termite maintains an anaerobic microbial community in its hindgut, which seems to be the minimum size of an anaerobic habitat. this microbial community consists of bacteria and various anaerobic flagellates, and it is established that termites are totally dependent on the microbes for the utilization of their food. the molecular phylogenetic diversity of the intestinal microflora of a lower termite, reticulitermes speratus, was examined by a strategy that does not rely on cultivation of the re ...19989783160
phylogenetic diversity of symbiotic methanogens living in the hindgut of the lower termite reticulitermes speratus analyzed by pcr and in situ hybridization.a phylogenetic analysis of the sequences of 60 clones of archaeal small-subunit rrna genes amplified from the termite reticulitermes speratus revealed that most of them (56 clones) clustered in the genus methanobrevibacter. three clones were classified in the order thermoplasmales. the methanobrevibacter-related symbionts were detected by in situ hybridization analysis.19999925625
metazoan cellulase genes from termites: intron/exon structures and sites of expression.endogenous endo-beta-1,4-glucanase (egase, ec 3.2.1.4) cdnas were cloned from representatives of the termite families termitidae and rhinotermitidae. these egases are all composed of 448 amino acids and belong to glycosyl hydrolase family 9 (ghf9), sharing high levels of identity (40-52%) with selected bacterial, mycetozoan and plant egases. like most plant egases, they consist of a single catalytic domain, lacking the ancillary domains found in most microbial cellulases. using a pcr-based strat ...199910542312
symbiotic spirochetes in the termite hindgut: phylogenetic identification of ectosymbiotic spirochetes of oxymonad protists.some species of protists inhabiting the hindgut of lower-termites have a large number of ectosymbiotic spirochetes on the cell surface. the phylogenetic positions of the ectosymbiotic spirochetes of three oxymonad protists, dinenympha porteri in the gut of reticulitermes speratus, and pyrsonympha sp. and dinenympha sp. in hodotermopsis sjoestedti, were investigated without cultivation of these organisms. protist fractions carefully collected with a micromanipulator were used as templates for the ...200011053732
molecular phylogeny of methanogens associated with flagellated protists in the gut and with the gut epithelium of termites.the molecular phylogeny of methanogenic archaea associated with the flagellated protist species dinenympha and microjoenia in the gut of termites, reticulitermes speratus and hodotermopsis sjoestedti, and those attached to the gut epithelium was examined based on pcr-amplified small-subunit ribosomal rna genes. the sequences identified were classified into six groups within the genus methanobrevibacter, including groups of yet uncharacterized novel species. closely related methanogens were share ...200011098074
phylogenetic diversity of termite gut spirochaetes.a molecular phylogenetic analysis was done of not-yet-cultured spirochaetes inhabiting the gut of the termite, reticulitermes flavipes (kollar). ninety-eight clones of near-full-length spirochaetal 16s rdna genes were classified by ardra pattern and by partial sequencing. all clones grouped within the genus treponema, and at least 21 new species of treponema were recognized within r. flavipes alone. analysis of 190 additional clones from guts of coptotermes formosanus shiraki and zootermopsis an ...199911207751
homosexual tandem running as selfish herd in reticulitermes speratus: novel antipredatory behavior in termites.we investigated the predator avoidance mechanism of post-swarming alates of the lower subterranean termite, reticulitermes speratus kolbe. in some lower termites, homosexual tandem running is observed in addition to ordinary heterosexual tandem running. an experiment designed to compare the risk of predation by a termite-hunting ant, brachyponera chinensis emery, showed that homosexual tandem running reduced the predation risk until termites encounter the opposite sex. since an individual ant ca ...200211786032
phylogenetic position and in situ identification of ectosymbiotic spirochetes on protists in the termite gut.phylogenetic relationships, diversity, and in situ identification of spirochetes in the gut of the termite neotermes koshunensis were examined without cultivation, with an emphasis on ectosymbionts attached to flagellated protists. spirochetes in the gut microbial community investigated so far are related to the genus treponema and divided into two phylogenetic clusters. in situ hybridizations with a 16s rrna-targeting consensus oligonucleotide probe for one cluster (known as termite treponema c ...200312514050
origin of a new reticulitermes termite (isoptera, rhinotermitidae) inferred from mitochondrial and nuclear dna data.the holoarctic termite genus reticulitermes is widely distributed in europe. a new reticulitermes species, r. sp. nov, was recently found in france and italy. its phylogenetic position was investigated using a 743-bp fragment of mitochondrial 16s rrna-nd1 genes and 382-bp of the nuclear its2 region. phylogenies for these sequences were estimated by neighbor-joining, maximum-parsimony and maximum-likelihood analysis. the results strongly supported a relationship between r. sp. nov. and the termit ...200414715226
biological activity of alpha-thujaplicin, the isomer of hinokitiol.alpha-thujaplicin, a minor component of aomori hiba (thujopsis dolabrata sieb. et zucc. var. hondai makino), showed rather strong antifungal activity against seven kinds of plant-pathogenic fungi, their minimum inhibitory concentrations (mics) being in the range of 12.0-50.0 microg/ml. alpha-thujaplicin and hinokitiol (the major component of aomori hiba) also showed clear antibacterial activity against legionella pneumophila sg 1 and l. pneumophila sg 3, and their mics are in the range of 6.25-5 ...200415187442
major alteration of the expression site of endogenous cellulases in members of an apical termite lineage.termites are among the most important cellulose-digesting animals on earth, and are well-known for the symbiotic relationship they have with cellulolytic trichomonad and oxymonad flagellates (unicellular eukaryotes). perhaps less well-known is the fact that approximately 75% of the approximately 2600 described termite species -- those belonging to the family termitidae -- do not harbour such flagellates. unlike most termites from other families, the majority of termitids do not consume wood, fee ...200415367134
heterologous overexpression of a mutant termite cellulase gene in escherichia coli by dna shuffling of four orthologous parental cdnas.among cellulase genes, those of animals are known for their difficulty in overexpression. we constructed a chimeric library by family shuffling of endo-beta-1,4-glucanase genes from four different termite species (reticulitermes speratus, nasutitermes takasagoensis, coptotermes formosanus, and coptotermes acinaciformis) sharing 78.5-96% homology in amino acid sequence. the constructed library was screened by congo red plate assay combined with 96-well micro-enzyme assay, and clones showing enhan ...200516195589
diversity of nitrogen fixation genes in the symbiotic intestinal microflora of the termite reticulitermes speratus.the diversity of nitrogen-fixing organisms in the symbiotic intestinal microflora of a lower termite, reticulitermes speratus, was investigated without culturing the resident microorganisms. fragments of the nifh gene, which encodes the dinitrogenase reductase, were directly amplified from the dna of the mixed microbial population in the termite gut and were clonally isolated. the phylogenetic analysis of the nifh product amino acid sequences showed that there was a remarkable diversity of nitro ...199616535372
termite-egg mimicry by a sclerotium-forming fungus.mimicry has evolved in a wide range of organisms and encompasses diverse tactics for defence, foraging, pollination and social parasitism. here, i report an extraordinary case of egg mimicry by a fungus, whereby the fungus gains competitor-free habitat in termite nests. brown fungal balls, called 'termite balls', are frequently found in egg piles of reticulitermes termites. phylogenetic analysis illustrated that termite-ball fungi isolated from different hosts (reticulitermes speratus, reticulit ...200616720392
environmental cdna analysis of the genes involved in lignocellulose digestion in the symbiotic protist community of reticulitermes speratus.to clarify the lignocellulolytic process of the lower termite symbiotic protistan system, we constructed a cdna library from an as yet uncultivated symbiotic protist community of the lower termite reticulitermes speratus. the library was constructed by the biotinylated cap trapper method and analyzed by one-pass sequencing. phylogenetic analysis of actin orthologs confirmed that the resulting library reflected the intact organismal and mrna composition of the symbiotic system. the contents of th ...200717239084
candidatus symbiothrix dinenymphae: bristle-like bacteroidales ectosymbionts of termite gut protists.many reports have stated that flagellated protists in termite guts harbour ectosymbiotic spirochetes on their cell surface. in this study, we describe another bristle-like ectosymbiont affiliated with the order bacteroidales. the 16s rrna phylotype rs-n74 predominates among bacteroidales clones obtained from the gut of the termite reticulitermes speratus. an rs-n74 phylotype-specific probe was designed in this study and used for detection of the corresponding bacteria in the gut by fluorescence ...200717803785
termiticidal activity of diterpenes from the roots of euphorbia kansui.five ingenane compounds, 1-5, kansuinins a and b, isolated from euphorbia kansui, and their derivatives 7 and 9 were tested for termiticidal activity against the japanese termite, reticulitermes speratus. at 72 hours after treatment, the ingenane compounds 1 to 5 caused 100% mortality in r. speratus at 50, 25 and 12.5 microg/disk, respectively, except for compound 1, which gave a mortality rate of (93.06 +/- 5.56)% at 12.5 microg/disk. at 36, 48 and 60 hours after treatment, compounds 1 to 5 sho ...200818386488
codon optimization prevents premature polyadenylation of heterologously-expressed cellulases from termite-gut symbionts in aspergillus oryzae.to achieve high expression of glycoside hydrolase family 45 endoglucanase (rssym45eg1) from a symbiotic protist of the termite reticulitermes speratus, synthetic sequence rssym45eg1-co, in which the codon usage was adjusted to that of the highly-expressed tef1 gene encoding translation elongation factor 1alpha, was prepared and introduced into a. oryzae. the transcript level of rssym45eg1-co was 1.8-fold higher than that of rssym45eg1. in cells harboring rssym45eg1, but not rssym45eg1-co, trunca ...200819164877
candidatus desulfovibrio trichonymphae, a novel intracellular symbiont of the flagellate trichonympha agilis in termite gut.rs-n31, a 16s rrna phylotype affiliated with the genus desulfovibrio, has frequently been detected from the gut of the wood-feeding termite reticulitermes speratus. in this study, we designed a probe specifically targeting phylotype rs-n31 and performed fluorescence in situ hybridization to identify the corresponding cells. the signals were detected exclusively inside the cells of the flagellate trichonympha agilis, which simultaneously harbours another intracellular bacterium belonging to the c ...200919170725
heterologous expression and characterization of an endoglucanase from a symbiotic protist of the lower termite, reticulitermes speratus.rssymeg, an endoglucanase of glycosyl hydrolase family (ghf) 7 encoded by a transcript isolated from the symbiotic protist of the termite reticulitermes speratus, is expressed in aspergillus oryzae. interestingly, purified rssymeg1 has a relatively higher specific activity (603 micromol min(-1) mg(-1) protein) and v(max) value (769.6 unit/mg protein) than previously reported data for ghf7 endoglucanase of trichoderma ressei. it also has the same k(m) value (1.97 mg/ml) with clostridium celluloly ...201019404781
molecular analysis of bacterial microbiota in the gut of the termite reticulitermes speratus (isoptera; rhinotermitidae).the molecular diversity and community structure of bacteria from the gut of the termite reticulitermes speratus were analyzed by the sequencing of near-full-length 16s rrna genes, amplified by polymerase chain reaction. the results of the analysis of 1344 clones indicated a predominance of spirochetes in the gut. spirochetal clones accounted for approximately half of the analyzed clones. the clones related to bacteroides, clostridia, and the candidate division termite group i each accounted for ...200319719640
fumigant antitermitic activity of plant essential oils and components from ajowan ( trachyspermum ammi ), allspice ( pimenta dioica ), caraway ( carum carvi ), dill ( anethum graveolens ), geranium ( pelargonium graveolens ), and litsea ( litsea cubeba ) oils against japanese termite ( reticulitermes speratus kolbe).plant essential oils from 26 plant species were tested for their insecticidal activities against the japanese termite, reticulitermes speratus kolbe, using a fumigation bioassay. responses varied with source, exposure time, and concentration. among the essential oils tested, strong insecticidal activity was observed with the essential oils of ajowan ( trachyspermum ammi ), allspice ( pimenta dioica ), caraway ( carum carvi ), dill ( anethum graveolens ), geranium ( pelargonium graveolens ), and ...200919722567
[phylogenetic analysis of symbiotic archaea in the gut of reticulitermes chinensis snyder].to analyze the phylotypes of symbiotic archaea in the gut of reticulitermes chinensis snyder by using non-cultivating method.200920222453
identification of activity related amino acid mutations of a gh9 termite cellulase.site-directed mutagenesis of the endo-beta-1,4-glucanase (eg) gene from the termite reticulitermes speratus eg (rseg) was performed to gain a better understanding of the role of certain amino acid residues in the activity of the enzyme. three mutants, g91a, y97w and k429a had higher activities towards carboxymethyl cellulose than the wild type. the mutations had synergistic effects since each single mutant exhibited about 3-4-fold of wild type activity, but the corresponding activities for doubl ...201020362432
symbiotic adaptation of bacteria in the gut of reticulitermes speratus: low endo-beta-1,4-glucanase activity.the termite is a good model of symbiosis between microbes and hosts and possesses an effective cellulose digestive system. oxygen-tolerant bacteria, such as dyella sp., chryseobacterium sp., and bacillus sp., were isolated from reticulitermes speratus gut. notably, the endo-beta-1,4-glucanase (eg) activity of all 16 strains of isolated bacteria was low. due to the combined activity of eg from the termites and their symbiotic protozoa, the bacteria might not be compelled to express eg. this obser ...201020385103
purification and characterization of termite endogenous beta-1,4-endoglucanases produced in aspergillus oryzae.although termites are known to have a highly efficient lignocellulose-digesting system, mass production of native endogenous cellulases of termites has failed in escherchia coli, and in saccharomyces cerevisiae, and it has not been accomplished. here we report the successful production, purification, and characterization of two termite endogenous beta-1,4-endoglucanases, rseg and nteg, from the salivary gland of reticulitermes speratus and the midgut of nasutitermes takasagoensis respectively, u ...201020699551
characterization of a new endogenous endo-β-1,4-glucanase of formosan subterranean termite (coptotermes formosanus).the present work characterized a new endogenous cellulase (endo-β-1,4-glucanase) gene, cfeg5, uncovered in the transcriptome of formosan subterranean termite (coptotermes formosanus). the full-length gene was cloned and sequenced. it is similar to the cfeg3a described earlier (zhang et al., 2009) but not likely an allelic variant. genomewalker™ dna walking analysis indicated that there may be one copy of cfeg5 and two copies of cfeg3a in the termite genome. as with cfeg3a, the transcript of cfeg ...201021195179
caste-specific and sex-specific expression of chemoreceptor genes in a termite.the sophisticated colony organization of eusocial insects is primarily maintained through the utilization of pheromones. the regulation of these complex social interactions requires intricate chemoreception systems. the recent publication of the genome of zootermopsis nevadensis opened a new avenue to study molecular basis of termite caste systems. although there has been a growing interest in the termite chemoreception system that regulates their sophisticated caste system, the relationship bet ...201626760975
heterologous expression and characterization of a glycoside hydrolase family 45 endo-β-1,4-glucanase from a symbiotic protist of the lower termite, reticulitermes speratus.the termite symbiotic system is one of the efficient lignocellulose degradation systems. we tried to express and characterize a novel cellulolytic enzyme from this system. here, we report the isolation of an endo-β-1,4-glucanase gene homolog of glycoside hydrolase family 45 from a symbiotic protistan community of reticulitermes speratus. heterologous expression of this gene was performed using the expression system of aspergillus oryzae. analysis of enzymatic properties revealed 786 μmol/min/mg ...201323354496
bacteroides reticulotermitis sp. nov., isolated from the gut of a subterranean termite (reticulitermes speratus).an obligately anaerobic, non-pigmented, non-spore-forming, gram-staining-negative, rod-shaped bacterium, designated strain rs-03(t), was isolated from the gut of the subterranean termite reticulitermes speratus. the taxonomic position of the novel strain was determined by following a polyphasic approach. phylogenetic analyses based on 16s rrna gene sequences showed that strain rs-03(t) was a member of the genus bacteroides and was most closely related to bacteroides thetaiotaomicron jcm 5827(t) ...201322544795
comparison of intracellular "ca. endomicrobium trichonymphae" genomovars illuminates the requirement and decay of defense systems against foreign dna."candidatus endomicrobium trichonymphae" (bacteria; elusimicrobia) is an obligate intracellular symbiont of the cellulolytic protist genus trichonympha in the termite gut. a previous genome analysis of "ca endomicrobium trichonymphae" phylotype rs-d17 (genomovar ri2008), obtained from a trichonympha agilis cell in the gut of the termite reticulitermes speratus, revealed that its genome is small (1.1 mb) and contains many pseudogenes; it is in the course of reductive genome evolution. here we rep ...201627635050
intranuclear verrucomicrobial symbionts and evidence of lateral gene transfer to the host protist in the termite gut.in 1944, harold kirby described microorganisms living within nuclei of the protists trichonympha in guts of termites; however, their taxonomic assignment remains to be accomplished. here, we identified intranuclear symbionts of trichonympha agilis in the gut of the termite reticulitermes speratus. we isolated single nuclei of t. agilis, performed whole-genome amplification, and obtained bacterial 16s rrna genes by pcr. unexpectedly, however, all of the analyzed clones were from pseudogenes of 16 ...201424335826
"endomicrobia": cytoplasmic symbionts of termite gut protozoa form a separate phylum of prokaryotes.lignocellulose digestion by wood-feeding termites depends on the mutualistic interaction of unusual, flagellate protists located in their hindgut. most of the flagellates harbor numerous prokaryotic endosymbionts of so-far-unknown identity and function. using a full-cycle molecular approach, we show here that the endosymbionts of the larger gut flagellates of reticulitermes santonensis belong to the so-called termite group 1 (tg-1) bacteria, a group of clones previously obtained exclusively from ...200515746350
diversification of the microtubule system in the early stage of eukaryote evolution: elongation factor 1 alpha and alpha-tubulin protein phylogeny of termite symbiotic oxymonad and hypermastigote protists.the symbiotic protists of the lower termite have been regarded as a model of early-branched eukaryotes because of their simple cellular systems and morphological features. however, cultivation of these symbiotic protists is very difficult. for this reason, these interesting protists have not been well characterized in terms of their molecular biology. in research on these organisms which have not yet been cultivated, we developed a method for retrieving specific genes from a small number of cell ...200111139290
phylogenetic identification of the symbiotic hypermastigote trichonympha agilis in the hindgut of the termite reticulitermes speratus based on small-subunit rrna sequence.the phylogeny of a symbiotic hypermastigote trichonympha agilis (class parabasalia; order hypermastigida) in the hindgut of the lower termite reticulitermes speratus was examined by a strategy that does not rely on cultivation. from mixed-population dna obtained from the termite gut, small subunit (16s-like) ribosomal rna sequences were directly amplified by the polymerase chain reaction method using primers specific for eukaryotes. comparative sequence analysis of the clones revealed two kinds ...20099703680
cellulose and xylan utilisation in the lower termite reticulitermes speratus.the distribution of the enzymes of cellulose and xylan metabolism namely endo-beta-1,4-glucanase, beta-glucosidase, endo-beta-1,4-xylanase and beta-xylosidase activities, in reticulitermes speratus (kolbe) was measured both in the salivary glands and in the major gut sections and along the length of the gut in freshly collected termites. the majority of the endo-beta-1,4-glucanase activity (77.8%) was found in the salivary glands which also contained 23.9% of the beta-glucosidase activity. at le ...199712769907
fumigant activity of plant essential oils and components from garlic (allium sativum) and clove bud (eugenia caryophyllata) oils against the japanese termite (reticulitermes speratus kolbe).plant essential oils from 29 plant species were tested for their insecticidal activities against the japanese termite, reticulitermes speratus kolbe, using a fumigation bioassay. responses varied with plant material, exposure time, and concentration. good insecticidal activity against the japanese termite was achived with essential oils of melaleuca dissitiflora, melaleuca uncinata, eucalyptus citriodora, eucalyptus polybractea, eucalyptus radiata, eucalyptus dives, eucalyptus globulus, orixa ja ...200515913300
toxicity and feeding deterrent effect of 2-methylanthraquinone from the wood extractives of tectona grandis on the subterranean termites coptotermes formosanus and reticulitermes speratus.no-choice feeding tests using ethanol, chloroform, and acetone extractives of teak (tectona grandis) heartwood clearly showed feeding deterrent activity and toxicity to the subterranean termite reticulitermes speratus. the amount of 2-methylanthraquinone (maq) in teak wood extractives was not related to the feeding deterrents or toxicity, as shown by the no-choice feeding tests conducted using crude extractives containing various amounts of maq, maq alone, and fractions of crude extractives. as ...201627834795
using hidden markov models to characterize termite traveling behavior in tunnels with different curvatures.subterranean termites live underground and build tunnel networks to obtain food and nesting space. after obtaining food, termites return to their nests to transfer it. the efficiency of termite movement through the tunnels is directly connected to their survival. tunnels should therefore be optimized to ensure highly efficient returns. an optimization factor that strongly affects movement efficiency is tunnel curvature. in the present study, we investigated traveling behavior in tunnels with dif ...201525562190
do termites avoid carcasses? behavioral responses depend on the nature of the carcasses.undertaking behavior is a significant adaptation to social life in enclosed nests. workers are known to remove dead colony members from the nest. such behavior prevents the spread of pathogens that may be detrimental to a colony. to date, little is known about the ethological aspects of how termites deal with carcasses.201222558452
the potential and limits of termites (isoptera) as decomposers of waste paper products.termites (isoptera) have often been proposed as decomposers oflignocellulosic waste, such as paper products, while termite biomass could be harvested for food supplements. groups of coptotermes formosanus shiraki and reticulitermes speratus (kolbe) were kept for 4 and 8 wk, respectively, in the laboratory and given up to 10 different types of paper as their food source. paper consumption, survival, caste composition, and lipid content were recorded. corrugated cardboard was by far the most consu ...201121404863
identification of two subterranean termite species (isoptera: rhinotermitidae) using cellulase genes.to identify subterranean termite species, we designed a pair of common primers that amplified 381-bp fragments from cdnas encoding the endo-beta-1,4-glucanases (egases) of coptotermes formosanus shiraki and reticulitermes speratus (kolbe). cdnas from c. formosanus and r. speratus, and genomic dna from r. speratus, were amplified by polymerase chain reaction (pcr) by using this primer pair and then cloned and sequenced. sequences amplified from c.formosanus cdna displayed 97-99% identity to cdna ...200616573332
complete genome sequence of elizabethkingia sp. bm10, a symbiotic bacterium of the wood-feeding termite reticulitermes speratus kmt1.elizabethkingia sp. bm10 was isolated from the hindgut of the wood-feeding termite reticulitermes speratus kmt1. it had cellobiohydrolase and β-glucosidase activities but not endo-β-glucanase activity. the complete sequence of its genome, which has a total size of 4,242,519 bases, is reported here. the genomic analysis identified six β-glucosidase candidate genes and three β-glucanase candidate genes.201526450743
dysgonomonas termitidis sp. nov., isolated from the gut of the subterranean termite reticulitermes speratus.a facultatively anaerobic, gram-stain-negative, non-motile and rod-shaped bacterium, strain n-10(t), was isolated from the gut of the termite reticulitermes speratus. strain n-10(t) was closely related to dysgonomonas gadei jcm 16698(t) according to 16s rrna gene sequence similarity analysis (98 %) and dna-dna relatedness value (≤61.3 %). the optimum growth temperature of strain n-10(t) was 30 °c, which was distinct from that (37 °c) of known species of the genus dysgonomonas. growth of strain n ...201525428419
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