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cellulose degradation by leucocoprinus gongylophorus, the fungus cultured by the leaf-cutting ant atta sexdens rubropilosa.leucocoprinus gongylophorus, the fungus cultured by the leaf-cutting ant atta sexdens rubropilosa, is able to degrade efficiently cellulose, microcrystaline cellulose, carboximethylcellulose, and cellobiose. analysis of the degradation products indicate that the fungus produce extracellular beta-glucosidase, exo- and endo-glucanase. the importance of cellulose degradation to the association of fungus and ant is discussed.19957574556
production of polysaccharidases in different carbon sources by leucoagaricus gongylophorus möller (singer), the symbiotic fungus of the leaf-cutting ant atta sexdens linnaeus.leucoagaricus gongylophorus, the fungus cultured by the leaf-cutting ant atta sexdens, produces polysaccharidases that degrade leaf components by generating nutrients believed to be essential for ant nutrition. we evaluated pectinase, amylase, xylanase, and cellulase production by l. gongylophorus in laboratory cultures and found that polysaccharidases are produced during fungal growth on pectin, starch, cellulose, xylan, or glucose but not cellulase, whose production is inhibited during fungal ...200616775790
leaf-cutter ant fungus gardens are biphasic mixed microbial bioreactors that convert plant biomass to polyols with biotechnological applications.leaf-cutter ants use plant matter to culture the obligate mutualistic basidiomycete leucoagaricus gongylophorus. this fungus mediates ant nutrition on plant resources. furthermore, other microbes living in the fungus garden might also contribute to plant digestion. the fungus garden comprises a young sector with recently incorporated leaf fragments and an old sector with partially digested plant matter. here, we show that the young and old sectors of the grass-cutter atta bisphaerica fungus gard ...201525911490
the most relictual fungus-farming ant species cultivates the most recently evolved and highly domesticated fungal symbiont species.fungus-farming (attine) ant agriculture is made up of five known agricultural systems characterized by remarkable symbiont fidelity in which five phylogenetic groups of ants faithfully cultivate five phylogenetic groups of fungi. here we describe the first case of a lower-attine ant cultivating a higher-attine fungus based on our discovery of a brazilian population of the relictual fungus-farming ant apterostigma megacephala, known previously from four stray specimens from peru and colombia. we ...201525905511
enrichment and broad representation of plant biomass-degrading enzymes in the specialized hyphal swellings of leucoagaricus gongylophorus, the fungal symbiont of leaf-cutter ants.leaf-cutter ants are prolific and conspicuous constituents of neotropical ecosystems that derive energy from specialized fungus gardens they cultivate using prodigious amounts of foliar biomass. the basidiomycetous cultivar of the ants, leucoagaricus gongylophorus, produces specialized hyphal swellings called gongylidia that serve as the primary food source of ant colonies. gongylidia also contain plant biomass-degrading enzymes that become concentrated in ant digestive tracts and are deposited ...201526317212
correction: enrichment and broad representation of plant biomass-degrading enzymes in the specialized hyphal swellings of leucoagaricus gongylophorus, the fungal symbiont of leaf-cutter ants. 201526398520
functional characterization of a yellow laccase from leucoagaricus gongylophorus.in this work we have identified, using mass spectrometry, two laccases produced by leucoagaricus gongylophorus. one of them, lac1lg, was isolated, purified and characterized. lac1lg, a monomeric enzyme, was studied using abts and syringaldazine substrates. lac1lg presented kcat/km almost threefold higher for syringaldazine than for abts, showing a higher catalytic efficiency of lac1lg for syringaldazine. the interference of several metal ions and substances in the laccase activity were evaluated ...201526543788
somatic incompatibility and genetic structure of fungal crops in sympatric atta colombica and acromyrmex echinatior leaf-cutting ants.obligate mutualistic symbioses rely on mechanisms that secure host-symbiont commitments to maximize host benefits and prevent symbiont cheating. previous studies showed that somatic incompatibilities correlate with neutral-marker-based genetic distances between fungal symbionts of panamanian acromyrmex leaf-cutting ants, but the extent to which this relationship applies more generally remained unclear. here we showed that genetic distances accurately predicted somatic incompatibility for acromyr ...201526865859
ant mediated redistribution of a xyloglucanase enzyme in fungus gardens of acromyrmex echinatior.xyloglucan is an important component in plant cell walls that herbivores cannot digest without microbial symbionts. leaf-cutting ants are major insect herbivores in the neo-tropics that rely on fungus-garden enzymes for degrading plant cell walls. however, many of these ants discard much of their harvested plant material after partial degradation, which has led to the hypothesis that the fungal symbionts are primarily producing cell wall degrading enzymes to gain access to intracellular nutrient ...201627154066
the fungal cultivar of leaf-cutter ants produces specific enzymes in response to different plant substrates.herbivores use symbiotic microbes to help derive energy and nutrients from plant material. leaf-cutter ants are a paradigmatic example, cultivating their mutualistic fungus leucoagaricus gongylophorus on plant biomass that workers forage from a diverse collection of plant species. here, we investigate the metabolic flexibility of the ants' fungal cultivar for utilizing different plant biomass. using feeding experiments and a novel approach in metaproteomics, we examine the enzymatic response of ...201627696597
nature of the interactions between hypocrealean fungi and the mutualistic fungus of leaf-cutter ants.leaf-cutter ants cultivate and feed on the mutualistic fungus, leucoagaricus gongylophorus, which is threatened by parasitic fungi of the genus escovopsis. the mechanism of escovopsis parasitism is poorly understood. here, we assessed the nature of the antagonism of different escovopsis species against its host. we also evaluated the potential antagonism of escovopsioides, a recently described fungal genus from the attine ant environment whose role in the colonies of these insects is unknown. we ...201728040855
chemical basis of the synergism and antagonism in microbial communities in the nests of leaf-cutting ants.leaf-cutting ants cultivate the fungus leucoagaricus gongylophorus, which serves as a major food source. this symbiosis is threatened by microbial pathogens that can severely infect l. gongylophorus. microbial symbionts of leaf-cutting ants, mainly pseudonocardia and streptomyces, support the ants in defending their fungus gardens against infections by supplying antimicrobial and antifungal compounds. the ecological role of microorganisms in the nests of leaf-cutting ants can only be addressed i ...201121245311
a mixed community of actinomycetes produce multiple antibiotics for the fungus farming ant acromyrmex octospinosus.attine ants live in an intensely studied tripartite mutualism with the fungus leucoagaricus gongylophorus, which provides food to the ants, and with antibiotic-producing actinomycete bacteria. one hypothesis suggests that bacteria from the genus pseudonocardia are the sole, co-evolved mutualists of attine ants and are transmitted vertically by the queens. a recent study identified a pseudonocardia-produced antifungal, named dentigerumycin, associated with the lower attine apterostigma dentigerum ...201020796277
effect of tithonia diversifolia mulch on atta cephalotes (hymenoptera: formicidae) nests.recent studies have shown an insecticidal effect of tithonia diversifolia (hemsl.) gray (asterales: asteraceae) foliage on workers of atta cephalotes l. and inhibitory effects of this plant on the growth of the symbiotic fungus leucoagaricus gongylophorus (a. müler) singer. to evaluate the potential of t. diversifolia as a biological control treatment of this important pest, we assessed the effect of green manure (mulch) of this plant on natural nests of a. cephalotes, in cali, colombia. three t ...201525843585
symbiotic adaptations in the fungal cultivar of leaf-cutting ants.centuries of artificial selection have dramatically improved the yield of human agriculture; however, strong directional selection also occurs in natural symbiotic interactions. fungus-growing attine ants cultivate basidiomycete fungi for food. one cultivar lineage has evolved inflated hyphal tips (gongylidia) that grow in bundles called staphylae, to specifically feed the ants. here we show extensive regulation and molecular signals of adaptive evolution in gene trancripts associated with gongy ...201425435021
a brazilian population of the asexual fungus-growing ant mycocepurus smithii (formicidae, myrmicinae, attini) cultivates fungal symbionts with gongylidia-like structures.attine ants cultivate fungi as their most important food source and in turn the fungus is nourished, protected against harmful microorganisms, and dispersed by the ants. this symbiosis evolved approximately 50-60 million years ago in the late paleocene or early eocene, and since its origin attine ants have acquired a variety of fungal mutualists in the leucocoprineae and the distantly related pterulaceae. the most specialized symbiotic interaction is referred to as "higher agriculture" and inclu ...201425101899
the prominent role of fungi and fungal enzymes in the ant-fungus biomass conversion symbiosis.molecular studies have added significantly to understanding of the role of fungi and fungal enzymes in the efficient biomass conversion, which takes place in the fungus garden of leaf-cutting ants. it is now clear that the fungal symbiont expresses the full spectrum of genes for degrading cellulose and other plant cell wall polysaccharides. since the start of the genomics era, numerous interesting studies have especially focused on evolutionary, molecular, and organismal aspects of the biologica ...201424728757
molecular and kinetic characterization of two extracellular xylanases isolated from leucoagaricus gongylophorus.in this work, the xylanolytic profile of leucoagaricus gongylophorus was studied, and two extracellular enzymes with xylanolytic activity (xylg1 and xylg2) were isolated, purified, and characterized. xylg1 has a molecular mass of about 38 kda and pi greater than 4.8. for beechwood xylan substrate, xylg1 showed an optimum temperature of 40 °c, optimum ph between 8.5 and 10.5, and km = 14.7 ± 7.6 mg ml(-1). kinetic studies of the xylg1 using polygalacturonic acid as substrate were developed, and t ...201424699813
leucoagaricus gongylophorus uses leaf-cutting ants to vector proteolytic enzymes towards new plant substrate.the mutualism between leaf-cutting ants and their fungal symbionts revolves around processing and inoculation of fresh leaf pulp in underground fungus gardens, mediated by ant fecal fluid deposited on the newly added plant substrate. as herbivorous feeding often implies that growth is nitrogen limited, we cloned and sequenced six fungal proteases found in the fecal fluid of the leaf-cutting ant acromyrmex echinatior and identified them as two metalloendoproteases, two serine proteases and two as ...201424401858
the fungal symbiont of acromyrmex leaf-cutting ants expresses the full spectrum of genes to degrade cellulose and other plant cell wall polysaccharides.the fungus gardens of leaf-cutting ants are natural biomass conversion systems that turn fresh plant forage into fungal biomass to feed the farming ants. however, the decomposition potential of the symbiont leucocoprinus gongylophorus for processing polysaccharides has remained controversial. we therefore used quantifiable deepsage technology to obtain mrna expression patterns of genes coding for secreted enzymes from top, middle, and bottom sections of a laboratory fungus-garden of acromyrmex e ...201324373541
leucoagaricus gongylophorus produces diverse enzymes for the degradation of recalcitrant plant polymers in leaf-cutter ant fungus gardens.plants represent a large reservoir of organic carbon comprised primarily of recalcitrant polymers that most metazoans are unable to deconstruct. many herbivores gain access to nutrients in this material indirectly by associating with microbial symbionts, and leaf-cutter ants are a paradigmatic example. these ants use fresh foliar biomass as manure to cultivate gardens composed primarily of leucoagaricus gongylophorus, a basidiomycetous fungus that produces specialized hyphal swellings that serve ...201323584789
laccase detoxification mediates the nutritional alliance between leaf-cutting ants and fungus-garden symbionts.leaf-cutting ants combine large-scale herbivory with fungus farming to sustain advanced societies. their stratified colonies are major evolutionary achievements and serious agricultural pests, but the crucial adaptations that allowed this mutualism to become the prime herbivorous component of neotropical ecosystems has remained elusive. here we show how coevolutionary adaptation of a specific enzyme in the fungal symbiont has helped leaf-cutting ants overcome plant defensive phenolic compounds. ...201223267060
frontier mutualism: coevolutionary patterns at the northern range limit of the leaf-cutter ant-fungus symbiosis.tropical leaf-cutter ants cultivate the fungus attamyces bromatificus in a many-to-one, diffuse coevolutionary relationship where ant and fungal partners re-associate frequently over time. to evaluate whether ant-attamyces coevolution is more specific (tighter) in peripheral populations, we characterized the host-specificities of attamyces genotypes at their northern, subtropical range limits (southern usa, mexico and cuba). population-genetic patterns of northern attamyces reveal features that ...201121389026
a metabolic pathway assembled by enzyme selection may support herbivory of leaf-cutter ants on plant starch.mutualistic associations shape the evolution in different organism groups. the association between the leaf-cutter ant atta sexdens and the basidiomycete fungus leucoagaricus gongylophorus has enabled them to degrade starch from plant material generating glucose, which is a major food source for both mutualists. starch degradation is promoted by enzymes contained in the fecal fluid that ants deposit on the fungus culture in cut leaves inside the nests. to understand the dynamics of starch degrad ...201323500892
metabolism of plant polysaccharides by leucoagaricus gongylophorus, the symbiotic fungus of the leaf-cutting ant atta sexdens latta sexdens l. ants feed on the fungus they cultivate on cut leaves inside their nests. the fungus, leucoagaricus gongylophorus, metabolizes plant polysaccharides, such as xylan, starch, pectin, and cellulose, mediating assimilation of these compounds by the ants. this metabolic integration may be an important part of the ant-fungus symbiosis, and it involves primarily xylan and starch, both of which support rapid fungal growth. cellulose seems to be less important for symbiont nutrition, since ...19989835568
acromyrmex octospinosus (hymenoptera: formicidae) management: effects of tramils fungicidal plant extracts.leaf-cutting ants, acromyrmex octospinosus (reich), are considering among the most important pest species of the new world. until now, the main insecticides used for controlling these ants were synthetic chemicals. leaf-cutting ants live in obligate symbiosis with abasidiomycete fungus, leucocoprinus gongylophorus (heim) moeller. the crucial role of this symbiotic partner in the nest of leaf-cutting ants has prompted us to focus on a. octospinosus management through the use of fungicides in our ...201222928301
random amplified polymorphic dna markers reveal genetic variation in the symbiotic fungus of leaf-cutting ants.rapd markers were used to examine the degree of genetic variation within the putatively asexual basidiomycete fungus (lepiotaceae: provisionally named leucoagaricus gongylophorus) associated with the leaf-cutting ant species atta cephalotes. we analyzed fungal isolates from ant nests in two geographically distant sites, two isolates from panama and five isolates from trinidad. ten decamer primers were used to amplify total dna from these seven fungal isolates, and rapd banding patterns were comp ...200321156584
immobilization of pectinase from leucoagaricus gongylophorus on magnetic particles.polygalacturonases (ec 3.2.1.15) hydrolyze the α-1,4-glycosidic linkages in polygalacturonic acid chains. the interest on specific inhibitors of pectinase and the versatility of magnetic support for enzyme immobilization endorsed the preparation of an immobilized enzyme reactor (imer). this work presents the synthesis of cofe(2)o(4) amino-derivatives, which was employed as the support for the immobilization of pectinases from leucoagaricus gongylophorus. amino-functionalized cofe(2)o(4) was obta ...201222946085
toxicity of synthetic piperonyl compounds to leaf-cutting ants and their symbiotic fungus.the development of leucoagaricus gongylophorus, the fungus cultured by the leaf-cutting ant atta sexdens was inhibited in vitro by synthetic compounds containing the piperonyl group. in addition, worker ants that were fed daily on an artificial diet to which these compounds were added had a higher mortality rate than the controls. the inhibition of the fungal growth increased with the size of the carbon side chain ranging from c1 through c8 and decreasing thereafter. 1-(3,4-methylenedioxybenzylo ...200111464791
starch metabolism in leucoagaricus gongylophorus, the symbiotic fungus of leaf-cutting ants.leucoagaricus gongylophorus, the symbiotic fungus of the leaf-cutting ants, degrades starch, this degradation being supposed to occur in the plant material which leafcutters forage to the nests, generating most of the glucose which the ants utilize for food. in the present investigation, we show that laboratory cultures of l. gongylophorus produce extracellular alpha-amylase and maltase which degrade starch to glucose, reinforcing that the ants can obtain glucose from starch through the symbioti ...200616380244
rapid shifts in atta cephalotes fungus-garden enzyme activity after a change in fungal substrate (attini, formicidae).fungus gardens of the basidiomycete leucocoprinus gongylophorus sustain large colonies of leaf-cutting ants by degrading the plant material collected by the ants. recent studies have shown that enzyme activity in these gardens is primarily targeted toward starch, proteins and the pectin matrix associated with cell walls, rather than toward structural cell wall components such as cellulose and hemicelluloses. substrate constituents are also known to be sequentially degraded in different sections ...201121475686
isolation of xanthyletin, an inhibitor of ants' symbiotic fungus, by high-speed counter-current chromatography.xanthyletin, an inhibitor of symbiotic fungus (leucoagaricus gongylophorus) of leaf-cutting ant (atta sexdens rubropilosa), as well as suberosin, seselin and xanthoxyletin were isolated from citrus sinensis grafted on citrus limonia. a two-phase solvent system composed of hexane/ethanol/acetonitrile/water (10:8:1:1, v/v) was used for the high-speed counter-current chromatographic isolation of xanthyletin with high yield and over 99% purity as determined by liquid and gas chromatography with mass ...200919296958
the dynamics of plant cell-wall polysaccharide decomposition in leaf-cutting ant fungus gardens.the degradation of live plant biomass in fungus gardens of leaf-cutting ants is poorly characterised but fundamental for understanding the mutual advantages and efficiency of this obligate nutritional symbiosis. controversies about the extent to which the garden-symbiont leucocoprinus gongylophorus degrades cellulose have hampered our understanding of the selection forces that induced large scale herbivory and of the ensuing ecological footprint of these ants. here we use a recently established ...201121423735
leaf-cutting ant fungi produce cell wall degrading pectinase complexes reminiscent of phytopathogenic fungi.leaf-cutting (attine) ants use their own fecal material to manure fungus gardens, which consist of leaf material overgrown by hyphal threads of the basidiomycete fungus leucocoprinus gongylophorus that lives in symbiosis with the ants. previous studies have suggested that the fecal droplets contain proteins that are produced by the fungal symbiont to pass unharmed through the digestive system of the ants, so they can enhance new fungus garden growth.201021194476
hydrolytic enzymes of leaf-cutting ant fungi.the production of enzymes and the colonization of leaves by leucoagaricus gongylophorus were investigated to further understand the digestive interactions of leaf-cutting ant colonies. the enzymes detected were indicative of a saprophytic origin of this fungus, producing all the enzymes necessary for plant tissue breakdown. enhanced activities of certain enzymes in the fungus garden extracts may be due to the particular behaviour of the adult worker ants that concentrate fungal acquired enzymes ...200918848636
susceptibility of the ant-cultivated fungus leucoagaricus gongylophorus (agaricales: basidiomycota) towards microfungi.the aim of this study was to select virulent strains of microfungi against leucoagaricus gongylophorus, a symbiotic fungus cultivated by leaf-cutting ants. the results from in vitro assays showed that microfungal strains had a variable and significant impact on the colony development of l. gongylophorus. specifically, trichoderma harzianum, escovopsis weberi cbs 810.71 and e. weberi a088 were more effective, inhibiting the l. gongylophorus colonies by 75, 68 and 67%, respectively (p < 0.05) afte ...200616897590
low variation in ribosomal dna and internal transcribed spacers of the symbiotic fungi of leaf-cutting ants (attini: formicidae).leaf-cutting ants of the genera atta and acromyrmex (tribe attini) are symbiotic with basidiomycete fungi of the genus leucoagaricus (tribe leucocoprineae), which they cultivate on vegetable matter inside their nests. we determined the variation of the 28s, 18s, and 5.8s ribosomal dna (rdna) gene loci and the rapidly evolving internal transcribed spacers 1 and 2 (its1 and its2) of 15 sympatric and allopatric fungi associated with colonies of 11 species of leafcutter ants living up to 2,600 km ap ...200415448866
activity of ricinus communis (euphorbiaceae) and ricinine against the leaf-cutting ant atta sexdens rubropilosa (hymenoptera: formicidae) and the symbiotic fungus leucoagaricus gongylophorus.the focus of this study was the identification of compounds from plant extracts for use in crop protection. this paper reports on the toxic activity of fractions of leaf extracts of ricinus communis l (euphorbiaceae) and isolated active compounds in the leaf-cutting ant atta sexdens rubropilosa forel and its symbiotic fungus leucoagaricus gongylophorus (singer) möller. the main compounds responsible for activity against the fungus and ant in leaf extracts of r communis were found to be fatty aci ...200415382509
survival of atta sexdens workers on different food sources.leaf-cutting ants belonging to the tribe attini are major herbivores and important agriculture pests in the neotropics, these ants being thought to feed on the sap which exudes from the plant material which they cut and also on the mycelium of a symbiotic fungus that grows on plant material inside their nests in what is called "the fungus garden". however, we have found that the survival of atta sexdens worker ants on leaves, on mycelium of the ants' symbiotic fungus, leucoagaricus gongylophorus ...200312769984
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