| physiology and nutrition of treponema primitia, an h2/co2-acetogenic spirochete from termite hindguts. | treponema primitia strains zas-1 and zas-2, the first spirochetes to be isolated from termite hindguts (j. r. leadbetter, t. m. schmidt, j. r. graber, and j. a. breznak, science 283:686-689, 1999), were examined for nutritional, physiological, and biochemical properties relevant to growth and survival in their natural habitat. in addition to using h(2) plus co(2) as substrates, these strains were capable of homoacetogenic growth on mono- and disaccharides and (in the case of zas-2) methoxylated ... | 2004 | 15006747 |
| description of treponema azotonutricium sp. nov. and treponema primitia sp. nov., the first spirochetes isolated from termite guts. | long after their original discovery, termite gut spirochetes were recently isolated in pure culture for the first time. they revealed metabolic capabilities hitherto unknown in the spirochaetes division of the bacteria, i.e., h(2) plus co(2) acetogenesis (j. r. leadbetter, t. m. schmidt, j. r. graber, and j. a. breznak, science 283:686-689, 1999) and dinitrogen fixation (t. g. lilburn, k. s. kim, n. e. ostrom, k. r. byzek, j. r. leadbetter, and j. a. breznak, science 292:2495-2498, 2001). howeve ... | 2004 | 15006748 |
| biochemical characterization of a d-psicose 3-epimerase from treponema primitia zas-1 and its application on enzymatic production of d-psicose. | the rare sugar d-psicose is a hexoketose monosaccharide and a c-3 epimer of d-fructose. d-psicose is a novel functional sweetener with 70% of the sweetness but only 0.3% of the energy content of sucrose. generally, the industrial production of d-psicose involves a bioconversion from d-fructose induced by ketose 3-epimerases. | 2016 | 25809188 |
| selenium controls transcription of paralogous formate dehydrogenase genes in the termite gut acetogen, treponema primitia. | the termite gut spirochete, treponema primitia, is a co(2)-reductive acetogen that is phylogenetically distinct from other distantly related and more extensively studied acetogens such as moorella thermoacetica. research on t. primitia has revealed details about the role of spirochetes in co(2)-reductive acetogenesis, a process important to the mutualism occurring between termites and their gut microbial communities. here, a locus of the t. primitia genome containing wood-ljungdahl pathway genes ... | 2010 | 21966917 |
| genes for selenium dependent and independent formate dehydrogenase in the gut microbial communities of three lower, wood-feeding termites and a wood-feeding roach. | the bacterial wood-ljungdahl pathway for co(2)-reductive acetogenesis is important for the nutritional mutualism occurring between wood-feeding insects and their hindgut microbiota. a key step in this pathway is the reduction of co(2) to formate, catalysed by the enzyme formate dehydrogenase (fdh). putative selenocysteine- (sec) and cysteine- (cys) containing paralogues of hydrogenase-linked fdh (fdh(h)) have been identified in the termite gut acetogenic spirochete, treponema primitia, but knowl ... | 2011 | 20819103 |
| treponema isoptericolens sp. nov., a novel spirochaete from the hindgut of the termite incisitermes tabogae. | a novel spirochaete, treponema sp. strain spit5t, was isolated from hindgut contents of the drywood termite incisitermes tabogae (snyder). the cells of strain spit5t were motile, helical in shape, 0.4-0.5 microm in diameter and generally 12-20 microm long. the strain is obligately anaerobic and ferments different mono-, di- and oligosaccharides by forming ethanol as the main liquid fermentation end product. furthermore, strain spit5t was able to grow anaerobically with yeast extract as sole carb ... | 2008 | 18450692 |
| novel ultrastructures of treponema primitia and their implications for motility. | members of the bacterial phylum spirochaetes are generally helical cells propelled by periplasmic flagella. the spirochete treponema primitia is interesting because of its mutualistic role in the termite gut, where it is believed to cooperate with protozoa that break down cellulose and produce h(2) as a by-product. here we report the ultrastructure of t. primitia as obtained by electron cryotomography of intact, frozen-hydrated cells. several previously unrecognized external structures were reve ... | 2008 | 18248579 |
| electron cryotomography reveals novel structures of a recently cultured termite gut spirochete. | electron cryotromography, a relatively new methodology in the field of microbiology, has been exploited by murphy et al. (in this issue of molecular microbiology) in their analysis of the recently isolated termite gut spirochete treponema primitia. unique structures (bowls, arcades of hooks, cones at the cell ends, two layers of wall material) were evident from the analysis of its surface and internal constituents. these results, coupled to video microscopy analysis of swimming cells, allowed th ... | 2008 | 18221263 |
| in situ structure of the complete treponema primitia flagellar motor. | the bacterial flagellar motor is an amazing nanomachine: built from approximately 25 different proteins, it uses an electrochemical ion gradient to drive rotation at speeds of up to 300 hz (refs 1, 2). the flagellar motor consists of a fixed, membrane-embedded, torque-generating stator and a typically bidirectional, spinning rotor that changes direction in response to chemotactic signals. most structural analyses so far have targeted the purified rotor, and hence little is known about the stator ... | 2006 | 16885937 |
| expression profiles of fhs (fthfs) genes support the hypothesis that spirochaetes dominate reductive acetogenesis in the hindgut of lower termites. | reductive acetogenesis is an important metabolic process in the hindgut of wood-feeding termites. we analysed diversity and expression profiles of the bacterial fhs gene, a marker gene encoding a key enzyme of reductive acetogenesis, formyl tetrahydrofolate synthetase (fthfs), to identify the active homoacetogenic populations in representatives of three different termite families. clone libraries of polymerase chain reaction-amplified fhs genes from hindgut contents of reticulitermes santonensis ... | 2006 | 16817934 |
| folate cross-feeding supports symbiotic homoacetogenic spirochetes. | treponema primitia, an h2-consuming co2-reducing homoacetogenic spirochete in termite hindguts, requires an exogenous source of folate for growth. tetrahydrofolate (thf) acts as a c1 carrier in co2-reductive acetogenesis, a microbially mediated process important to the carbon and energy requirements of termites. to examine the hypothesis that other termite gut microbes probably supply some form of folate to t. primitia in situ, we used a bioassay to screen for and isolate folate-secreting bacter ... | 2005 | 15812016 |
| genome-wide effects of selenium and translational uncoupling on transcription in the termite gut symbiont treponema primitia. | when prokaryotic cells acquire mutations, encounter translation-inhibiting substances, or experience adverse environmental conditions that limit their ability to synthesize proteins, transcription can become uncoupled from translation. such uncoupling is known to suppress transcription of protein-encoding genes in bacteria. here we show that the trace element selenium controls transcription of the gene for the selenocysteine-utilizing enzyme formate dehydrogenase (fdhfsec) through a translation- ... | 2013 | 24222491 |
| catechol 2,3-dioxygenase and other meta-cleavage catabolic pathway genes in the 'anaerobic' termite gut spirochete treponema primitia. | microorganisms have evolved a spectacular diversity of metabolisms, some of which allow them to overcome environmental constraints, utilize abundant but inaccessible resources and drive nutrient cycling in various ecosystems. the termite hindgut microbial community is optimized to metabolize wood, and in recent years, the in situ physiological and ecological functions of community members have been researched. spirochetes are abundant in the termite gut, and herein, putative aromatic meta-cleava ... | 2014 | 24261591 |
| genomic analysis reveals multiple [fefe] hydrogenases and hydrogen sensors encoded by treponemes from the h(2)-rich termite gut. | we have completed a bioinformatic analysis of the hydrogenases encoded in the genomes of three termite gut treponeme isolates: hydrogenotrophic, homoacetogenic treponema primitia strains zas-1 and zas-2, and the hydrogen-producing, sugar-fermenting treponema azotonutricium zas-9. h(2) is an important free intermediate in the breakdown of wood by termite gut microbial communities, reaching concentrations in some species exceeding those measured for any other biological system. the spirochetes enc ... | 2011 | 21811792 |