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Andreas Brune - One of the best experts on this subject based on the ideXlab platform.
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the fibre associated cellulolytic bacterial community in the hindgut of wood feeding higher termites Nasutitermes spp
Environmental Microbiology, 2014Co-Authors: Aram Mikaelyan, Gaku Tokuda, Jurgen F H Strassert, Andreas BruneAbstract:Summary Termites digest lignocellulose with the help of their symbiotic gut microbiota. In the hindgut of evolutionary lower termites, a dense community of cellulolytic flagellates sequesters wood particles from the hindgut content into their digestive vacuoles. In higher termites (family Termitidae), which possess an entirely prokaryotic microbiota, the wood particles are available for bacterial colonization. Substantial particle-associated cellulase activities have been detected in the hindgut of Nasutitermes species, but the microorganisms responsible for these activities and their potential association with the wood fibres remain to be studied. Here, we used density-gradient centrifugation to separate wood fibres and adherent bacterial cells from cells freely suspended in the hindgut fluid. In Nasutitermes corniger, the fibre fraction contained 28% of the DNA and 45% of the cellulase activity in the luminal contents (P3 region). Community fingerprinting (terminal restriction fragment length polymorphism) and pyrotag sequencing analysis of the bacterial 16S rRNA genes demonstrated that the wood fibres in the hindgut of both N. corniger and N. takasagoensis are specifically colonized by members of Fibrobacteres, the TG3 phylum, and certain lineages of Spirochaetes characteristic of the gut microbiota of wood-feeding higher termites. We propose that the loss of flagellates in higher termites provided a new niche for fibre-associated cellulolytic bacteria.
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High-resolution analysis of gut environment and bacterial microbiota reveals functional compartmentation of the gut in wood-feeding higher termites (Nasutitermes spp.).
Applied and environmental microbiology, 2012Co-Authors: Tim Köhler, Rudolf H Scheffrahn, Carsten Dietrich, Andreas BruneAbstract:Higher termites are characterized by a purely prokaryotic gut microbiota and an increased compartmentation of their intestinal tract. In soil-feeding species, each gut compartment has different physicochemical conditions and is colonized by a specific microbial community. Although considerable information has accumulated also for wood-feeding species of the genus Nasutitermes, including cellulase activities and metagenomic data, a comprehensive study linking physicochemical gut conditions with the structure of the microbial communities in the different gut compartments is lacking. In this study, we measured high-resolution profiles of H2, O2, pH, and redox potential in the gut of Nasutitermes corniger termites, determined the fermentation products accumulating in the individual gut compartments, and analyzed the bacterial communities in detail by pyrotag sequencing of the V3-V4 region of the 16S rRNA genes. The dilated hindgut paunch (P3 compartment) was the only anoxic gut region, showed the highest density of bacteria, and accumulated H2 to high partial pressures (up to 12 kPa). Molecular hydrogen is apparently produced by a dense community of Spirochaetes and Fibrobacteres, which also dominate the gut of other Nasutitermes species. All other compartments, such as the alkaline P1 compartment (average pH, 10.0), showed high redox potentials and comprised small but distinct populations characteristic for each gut region. In the crop and the posterior hindgut compartments, the community was even more diverse than in the paunch. Similarities in the communities of the posterior hindgut and crop suggested that proctodeal trophallaxis or coprophagy also occurs in higher termites. The large sampling depths of pyrotag sequencing in combination with the determination of important physicochemical parameters allow cautious conclusions concerning the functions of particular bacterial lineages in the respective gut sections to be drawn.
Rudolf H Scheffrahn - One of the best experts on this subject based on the ideXlab platform.
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overview and current status of non native termites isoptera in florida
Florida Entomologist, 2013Co-Authors: Rudolf H ScheffrahnAbstract:ABSTRACT The origins and status of the non-endemic termite species established in Florida are reviewed including Cryptotermes brevis and Incisitermes minor (Kalotermitidae), Coptotermes formosanus, Co. gestroi, and Heteroterm.es sp. (Rhinotermitidae), and Nasutitermes corniger (Termitidae). A lone colony of Marginitermes hubbardi (Kalotermitidae) collected near Tampa was destroyed in 2002. Amature colony of an arboreal exotic, Nasutitermes acajutlae, was destroyed aboard a dry docked sailboat in Fort Pierce in 2012. Records used in this study were obtained entirely from voucher specimen data maintained in the University of Florida Termite Collection. Current distribution maps of each species in Florida are presented. Invasion history suggests that established populations of exotic termites, without human intervention, will continue to spread and flourish unabatedly in Florida within climatically suitable regions.
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Overview And Current Status of Non-Native Termites (Isoptera) in Florida §
Florida Entomologist, 2013Co-Authors: Rudolf H ScheffrahnAbstract:ABSTRACT The origins and status of the non-endemic termite species established in Florida are reviewed including Cryptotermes brevis and Incisitermes minor (Kalotermitidae), Coptotermes formosanus, Co. gestroi, and Heteroterm.es sp. (Rhinotermitidae), and Nasutitermes corniger (Termitidae). A lone colony of Marginitermes hubbardi (Kalotermitidae) collected near Tampa was destroyed in 2002. Amature colony of an arboreal exotic, Nasutitermes acajutlae, was destroyed aboard a dry docked sailboat in Fort Pierce in 2012. Records used in this study were obtained entirely from voucher specimen data maintained in the University of Florida Termite Collection. Current distribution maps of each species in Florida are presented. Invasion history suggests that established populations of exotic termites, without human intervention, will continue to spread and flourish unabatedly in Florida within climatically suitable regions.
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High-resolution analysis of gut environment and bacterial microbiota reveals functional compartmentation of the gut in wood-feeding higher termites (Nasutitermes spp.).
Applied and environmental microbiology, 2012Co-Authors: Tim Köhler, Rudolf H Scheffrahn, Carsten Dietrich, Andreas BruneAbstract:Higher termites are characterized by a purely prokaryotic gut microbiota and an increased compartmentation of their intestinal tract. In soil-feeding species, each gut compartment has different physicochemical conditions and is colonized by a specific microbial community. Although considerable information has accumulated also for wood-feeding species of the genus Nasutitermes, including cellulase activities and metagenomic data, a comprehensive study linking physicochemical gut conditions with the structure of the microbial communities in the different gut compartments is lacking. In this study, we measured high-resolution profiles of H2, O2, pH, and redox potential in the gut of Nasutitermes corniger termites, determined the fermentation products accumulating in the individual gut compartments, and analyzed the bacterial communities in detail by pyrotag sequencing of the V3-V4 region of the 16S rRNA genes. The dilated hindgut paunch (P3 compartment) was the only anoxic gut region, showed the highest density of bacteria, and accumulated H2 to high partial pressures (up to 12 kPa). Molecular hydrogen is apparently produced by a dense community of Spirochaetes and Fibrobacteres, which also dominate the gut of other Nasutitermes species. All other compartments, such as the alkaline P1 compartment (average pH, 10.0), showed high redox potentials and comprised small but distinct populations characteristic for each gut region. In the crop and the posterior hindgut compartments, the community was even more diverse than in the paunch. Similarities in the communities of the posterior hindgut and crop suggested that proctodeal trophallaxis or coprophagy also occurs in higher termites. The large sampling depths of pyrotag sequencing in combination with the determination of important physicochemical parameters allow cautious conclusions concerning the functions of particular bacterial lineages in the respective gut sections to be drawn.
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proteome insights into the symbiotic relationship between a captive colony of Nasutitermes corniger and its hindgut microbiome
The ISME Journal, 2011Co-Authors: Kristin E Burnum, Samuel O Purvine, Falk Warnecke, Stephen J Callister, Carrie D Nicora, Philip Hugenholtz, Rudolf H Scheffrahn, Richard D. Smith, Mary S LiptonAbstract:Proteome insights into the symbiotic relationship between a captive colony of Nasutitermes corniger and its hindgut microbiome
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synonymy of neotropical arboreal termites Nasutitermes corniger and n costalis isoptera termitidae nasutitermitinae with evidence from morphology genetics and biogeography
Annals of The Entomological Society of America, 2005Co-Authors: Rudolf H Scheffrahn, Jan Krecek, Allen L. Szalanski, James W. AustinAbstract:Morphological examination of soldiers and imagos assigned to Nasutitermes corniger or N. costalis from 13 Neotropical countries and 42 West Indian islands revealed congruent characters and biometric overlap. A portion of the mitochondrial DNA 16S rRNA gene was sequenced from nine N. costalis and N. corniger samples. Molecular phylogenetic analysis of the N. costalis/corniger DNA sequences relative to other Nasutitermes spp. supported the morphological evidence that these species are conspecific. Complementary biological, behavioral, biochemical, and reproductive ecology further support the presented synonymy. The senior synonym, N. corniger, is given nomenclatural precedence. The geographical distribution of N. corniger is revised.
M. Slaytor - One of the best experts on this subject based on the ideXlab platform.
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Atmospheric carbon dioxide and acetogenesis in the termite Nasutitermes walkeri (Hill)
Comparative Biochemistry and Physiology Part A: Physiology, 1994Co-Authors: C.m. Williams, M. Slaytor, P.c. Veivers, S.v. ClelandAbstract:Abstract CO 2 concentration inside Nasutitermes walkeri nests is higher than in the external atmosphere. At concentrations up to 2%, CO 2 absorption by the termite is dependent on atmospheric CO 2 concentration. Atmospheric CO 2 is reduced in vivo to acetate in the termite but the amount of acetate in the termite is constant and is not related to the atmospheric CO 2 concentration.
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Uric acid synthesis in freshly collected and laboratory-maintained Nasutitermes walkeri Hill
Insect Biochemistry and Molecular Biology, 1993Co-Authors: D.j. Chappell, M. SlaytorAbstract:Abstract Worker instars of Nasutitermes walkeri contain uric acid which becomes an increasing proportion of the dry weight and total nitrogen in older instars. Uric acid ranges from 3.50 ± 0.13 to 9.80 ± 0.27% dry wt in freshly collected non-larval neuter caste termites, with
S.v. Cleland - One of the best experts on this subject based on the ideXlab platform.
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Atmospheric carbon dioxide and acetogenesis in the termite Nasutitermes walkeri (Hill)
Comparative Biochemistry and Physiology Part A: Physiology, 1994Co-Authors: C.m. Williams, M. Slaytor, P.c. Veivers, S.v. ClelandAbstract:Abstract CO 2 concentration inside Nasutitermes walkeri nests is higher than in the external atmosphere. At concentrations up to 2%, CO 2 absorption by the termite is dependent on atmospheric CO 2 concentration. Atmospheric CO 2 is reduced in vivo to acetate in the termite but the amount of acetate in the termite is constant and is not related to the atmospheric CO 2 concentration.
Aram Mikaelyan - One of the best experts on this subject based on the ideXlab platform.
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the fibre associated cellulolytic bacterial community in the hindgut of wood feeding higher termites Nasutitermes spp
Environmental Microbiology, 2014Co-Authors: Aram Mikaelyan, Gaku Tokuda, Jurgen F H Strassert, Andreas BruneAbstract:Summary Termites digest lignocellulose with the help of their symbiotic gut microbiota. In the hindgut of evolutionary lower termites, a dense community of cellulolytic flagellates sequesters wood particles from the hindgut content into their digestive vacuoles. In higher termites (family Termitidae), which possess an entirely prokaryotic microbiota, the wood particles are available for bacterial colonization. Substantial particle-associated cellulase activities have been detected in the hindgut of Nasutitermes species, but the microorganisms responsible for these activities and their potential association with the wood fibres remain to be studied. Here, we used density-gradient centrifugation to separate wood fibres and adherent bacterial cells from cells freely suspended in the hindgut fluid. In Nasutitermes corniger, the fibre fraction contained 28% of the DNA and 45% of the cellulase activity in the luminal contents (P3 region). Community fingerprinting (terminal restriction fragment length polymorphism) and pyrotag sequencing analysis of the bacterial 16S rRNA genes demonstrated that the wood fibres in the hindgut of both N. corniger and N. takasagoensis are specifically colonized by members of Fibrobacteres, the TG3 phylum, and certain lineages of Spirochaetes characteristic of the gut microbiota of wood-feeding higher termites. We propose that the loss of flagellates in higher termites provided a new niche for fibre-associated cellulolytic bacteria.
