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Sample records for karenia brevis natural

  1. Brevetoxicosis in seabirds naturally exposed to Karenia brevis blooms along the central west coast of Florida.

    PubMed

    Fauquier, Deborah A; Flewelling, Leanne J; Maucher, Jennifer M; Keller, Martha; Kinsel, Michael J; Johnson, Christine K; Henry, Michael; Gannon, Janet G; Ramsdell, John S; Landsberg, Jan H

    2013-04-01

    Harmful algal bloom events caused by the dinoflagellate Karenia brevis occurred along the central west Florida, USA, coast from February 2005 through December 2005 and from August 2006 through December 2006. During these events, from 4 February 2005 through 28 November 2006, live, debilitated seabirds admitted for rehabilitation showed clinical signs that included disorientation, inability to stand, ataxia, and seizures. Testing of blood, biologic fluids, and tissues for brevetoxin by enzyme-linked immunosorbent assay found toxin present in 69% (n=95) of rehabilitating seabirds. Twelve of the 19 species of birds had evidence of brevetoxin exposure. Commonly affected species included Double-crested Cormorants (Phalacrocorax auritus), Brown Pelicans (Pelecanus occidentalis), Great Blue Herons (Ardea herodias), and Common Loons (Gavia immer). Serial blood and fecal samples taken from several live seabirds during rehabilitation showed that brevetoxin was cleared within 5-10 days after being admitted to the rehabilitation facility, depending on the species tested. Among seabirds that died or were euthanized, the highest brevetoxin concentrations were found in bile, stomach contents, and liver. Most dead birds had no significant pathologic findings at necropsy, thereby supporting brevetoxin-related mortality.

  2. Harmful algal toxins of the Florida red tide (Karenia brevis): natural chemical stressors in South Florida coastal ecosystems

    PubMed Central

    Henry, M. S.

    2009-01-01

    The Florida red tide is a descriptive name for high concentrations of the harmful marine alga, Karenia brevis. Although most prevalent along the south-west Florida coast, periodic blooms have occurred throughout the entire US and Mexico Gulf coasts and the Atlantic coast to North Carolina. This dinoflagellate produces a suite of polyether neurotoxins, called brevetoxins, that cause severe impacts to natural resources, as well as public health. These naturally produced biotoxins may represent one of the most common chemical stressors impacting South Florida coastal and marine ecosystems. Impacts include massive fish kills, marine mammal, sea turtle and sea bird mortalities, benthic community die-off and public health effects from shellfish contamination and inhalation of air-borne toxins. The primary mode of action is binding to voltage-gated sodium channels causing depolarization of nerve cells, thus interfering with nerve transmission. Other effects include immune depression, bronchial constriction and haemolysis. Parent algal toxins are synthesized within the unicellular organism, others are produced as metabolic products. Recent studies into the composition of brevetoxins in cells, water, air and organisms have shown PbTx-2 to be the primary intracellular brevetoxin that is converted over time to PbTx-3 when the cells are ruptured, releasing extracellular brevetoxins into the environment. Brevetoxins become aerosolized by bubble-mediated transport of extracellular toxins, the composition of which varies depending on the composition in the source water. Bivalved molluscs rapidly accumulate brevetoxins as they filter feed on K. brevis cells. However, the parent algal toxins are rapidly metabolized to other compounds, some of which are responsible for neurotoxic shellfish poisoning (NSP). These results provide new insight into the distribution, persistence and impacts of red tide toxins to south-west Florida ecosystems. PMID:18758951

  3. Brevetoxin in blood, biological fluids, and tissues of sea turtles naturally exposed to Karenia brevis blooms in central west Florida.

    PubMed

    Fauquier, Deborah A; Flewelling, Leanne J; Maucher, Jennifer; Manire, Charles A; Socha, Victoria; Kinsel, Michael J; Stacy, Brian A; Henry, Michael; Gannon, Janet; Ramsdell, John S; Landsberg, Jan H

    2013-06-01

    In 2005 and 2006, the central west Florida coast experienced two intense Karenia brevis red tide events lasting from February 2005 through December 2005 and August 2006 through December 2006. Strandings of sea turtles were increased in the study area with 318 turtles (n = 174, 2005; n = 144, 2006) stranding between 1 January 2005 and 31 December 2006 compared to the 12-yr average of 43 +/- 23 turtles. Live turtles (n = 61) admitted for rehabilitation showed clinical signs including unresponsiveness, paresis, and circling. Testing of biological fluids and tissues for the presence of brevetoxin activity by enzyme-linked immunosorbent assay found toxin present in 93% (52 of 56) of live stranded sea turtles, and 98% (42 of 43) of dead stranded sea turtles tested. Serial plasma samples were taken from several live sea turtles during rehabilitation and toxin was cleared from the blood within 5-80 days postadmit depending upon the species tested. Among dead animals the highest brevetoxin levels were found in feces, stomach contents, and liver. The lack of significant pathological findings in the majority of animals necropsied supports toxin-related mortality.

  4. Simulations of Karenia Brevis on the West Florida Shelf

    NASA Astrophysics Data System (ADS)

    Lenes, J. M.; Darrow, B. P.; Chen, F. R.; Walsh, J. J.; Dieterle, D. A.; Weisberg, R. H.

    2010-12-01

    The ecological model, HABSIM, was developed and tested to examine the initiation and maintenance of red tides of the toxic dinoflagellate Karenia brevis on the West Florida shelf (WFS). Phytoplankton competition among K. brevis, nitrogen fixing cyanophytes (Trichodesmium spp.), large siliceous phytoplankton (diatoms), and small non-siliceous phytoplankton (microflagellates) thus explores the sequence of events required to support the observed bloom from August to December 2001. The ecological model contains twenty two state variables within four submodels: atmospheric (iron deposition), biological (phytoplankton, bacteria, zooplankton, and fish), chemical (multiple species of carbon, nitrogen, phosphorus, silica, and iron), and benthic (nutrient regeneration). Here, we present results for the 2001 1-d hindcast simulations, with and without data assimilation of the Karenia state variable, as well as preliminary 3-d results.

  5. Lipid Class, Carotenoid, and Toxin Dynamics of Karenia Brevis (Dinophyceae) During Diel Vertical Migration

    EPA Science Inventory

    Karenia brevis’ (Hansen and Moestrup) internal lipid, carotenoid, and toxin concentrations are influenced by its ability to use ambient light and nutrients for growth and reproduction. This project investigated changes of K. brevis toxicity, lipid class and carotenoid concentrat...

  6. FATTY ACID AND STEROL COMPOSITION OF A KARENIA BREVIS BLOOM IN THE GULF OF MEXICO

    EPA Science Inventory

    In the Gulf of Mexico, recurring algal blooms, caused by Karenia brevis (formerly known as Gymnodinium breve), have significant adverse health and economic impacts. K. brevis is one member of a small group of dinoflagellates, related morphologically and by DNA-based phylogenetic ...

  7. Extraction and analysis of lipophilic brevetoxins from the red tide dinoflagellate Karenia brevis.

    PubMed

    Twiner, Michael J; Bottein Dechraoui, Marie-Yasmine; Wang, Zhihong; Mikulski, Christina M; Henry, Michael S; Pierce, Richard H; Doucette, Gregory J

    2007-10-01

    Efficient extraction and accurate analysis of lipophilic brevetoxins (PbTxs), produced by the harmful algal bloom (HAB) species Karenia brevis, are essential when assessing the toxicological potential of this dinoflagellate. One of the most commonly used brevetoxin extraction methodologies employs C18 solid-phase extraction (SPE). In this study, C18 SPEC discs were tested for extraction of spiked PbTx-3 in seawater and naturally produced brevetoxins from K. brevis. Quantification of brevetoxin in the extracts was determined using four independent methods: receptor binding assay (RBA), radioimmunoassay (RIA), neuroblastoma (N2A) cytotoxicity assay, and liquid chromatography/mass spectrometry (LC/MS). In addition to quantification of the brevetoxin concentration, LC/MS analysis provided identification of individual congeners and each of their hydrolyzed products. SPEC disc extractions prepared from sonicated cultures of non-brevetoxin-producing Karenia mikimotoi cultures spiked with PbTx-3 yielded extraction efficiencies of 108, 99, and 125% as determined by the RBA, RIA, and N2A cytotoxicity assay, respectively. In SPEC disc extracts of brevetoxin-producing K. brevis (isolate SP3) cultures, LC/MS analysis yielded the highest total concentrations, possibly due to the concurrent detection of hydrolytic brevetoxin congeners that accounted for up to 20% of the congener profile. Relative to the brevetoxin concentration as determined by LC/MS, the RBA, RIA, and N2A cytotoxicity assay detected 73, 83, and 51% of the total brevetoxin concentration. Stability experiments demonstrated that brevetoxins remain stable on the SPEC discs for at least 30 days, making this extraction method suitable for shipboard collections.

  8. PCR amplification of microsatellites from single cells of Karenia brevis preserved in Lugol's iodine solution.

    PubMed

    Henrichs, D W; Renshaw, M A; Santamaria, C A; Richardson, B; Gold, J R; Campbell, L

    2008-01-01

    A simple and effective protocol is described for multiplex polymerase chain reaction (PCR) amplification of single cells of Karenia brevis. The protocol requires minimum processing, avoids additions that might dilute target DNA template, and can be used on cells preserved in Lugol's iodine preservative. Destaining of Lugol's-preserved cells with sodium thiosulfate allowed successful amplification of single-copy, nuclear-encoded microsatellites in single cells of K. brevis that have been preserved for up to 6 years.

  9. Long-term increase in Karenia brevis abundance along the Southwest Florida Coast

    PubMed Central

    Brand, Larry E.; Compton, Angela

    2008-01-01

    Data collected along the southwest coast of Florida between Tampa Bay and Sanibel Island on the abundance of the toxic dinoflagellate Karenia brevis from 1954 to 2002 were examined for spatial and temporal patterns. K. brevis was found to be approximately 20-fold more abundant within 5 km of the shoreline than 20-30 km offshore. Overall, K. brevis was approximately 13-18-fold more abundant in 1994-2002 than in 1954-1963. In 1954-1963, K. brevis occurred primarily in the fall months. In 1994-2002, it was more abundant not only in the fall, but also in the winter and spring months. It is hypothesized that greater nutrient availability in the ecosystem is the most likely cause of this increase in K. brevis biomass, and the large increase in the human population and its activities in South Florida over the past half century is a major factor. PMID:18437245

  10. A new polyether ladder compound produced by the dinoflagellate Karenia brevis.

    PubMed

    Bourdelais, Andrea J; Jacocks, Henry M; Wright, Jeffrey L C; Bigwarfe, Paul M; Baden, Daniel G

    2005-01-01

    A new ladder-frame polyether compound containing five fused ether rings was isolated from laboratory cultures of the marine dinoflagellate Karenia brevis. This compound, named brevenal, and its dimethyl acetal derivative both competitively displace brevetoxin from its binding site in rat brain synaptosomes. Significantly, these compounds are also nontoxic to fish and antagonize the toxic effects of brevetoxins in fish. The structure and biological activity of brevenal, as well as the dimethyl acetal derivative, are described in this paper.

  11. Toxicity comparison between Chattonella marina and Karenia brevis using marine medaka (Oryzias melastigma): Evidence against the suspected ichthyotoxins of Chattonella marina.

    PubMed

    Shen, Min; Xu, Jingliang; Tsang, Tsui Yun; Au, Doris W T

    2010-07-01

    The marine alga Chattonella marina is often associated with massive fish mortality worldwide. Here, we challenge brevetoxins and free fatty acids as the ichthyotoxins of C. marina by comparing the toxicity of C. marina with a brevetoxins-producing alga Karenia brevis as well as their organic solvent extracts using the seawater medaka Oryzias melastigma. Opposite to K. brevis, toxicity of C. marina was highly correlated with its growth rate and exhibited no dose response relationship between cell density and fish mortality. Fish exposed to C. marina developed significant hyperventilation response, but K. brevis induced hypoventilation response in medaka. Moreover, the organic extracts from C. marina showed no toxicity to fish whereas organic extracts from K. brevis showed significantly higher toxicity than the whole K. brevis culture. The toxins produced by C. marina may be protein in nature or small and labile molecular compounds which are not able to be extracted by traditional organic extraction methods.

  12. Effects of Karenia brevis on clearance rates and bioaccumulation of brevetoxins in benthic suspension feeding invertebrates.

    PubMed

    Echevarria, Michael; Naar, Jerome P; Tomas, Carmelo; Pawlik, Joseph R

    2012-01-15

    Blooms of the toxic alga Karenia brevis occur along coastlines where sessile suspension feeding invertebrates are common components of benthic communities. We studied the effects of K. brevis on four benthic suspension feeding invertebrates common to the coast of the SE United States: the sponge Haliclona tubifera, the bryozoan Bugula neritina, the bivalve Mercenaria mercenaria, and the tunicate Styela plicata. In controlled laboratory experiments, we determined the rate at which K. brevis was cleared from the seawater by these invertebrates, the effect of K. brevis on clearance rates of a non-toxic phytoplankton species, Rhodomonas sp., and the extent to which brevetoxins bioaccumulated in tissues of invertebrates using an enzyme-linked immunosorbent assay (ELISA). All four invertebrate species cleared significant quantities of K. brevis from seawater, with mean clearance rates ranging from 2.27 to 6.71 L g h⁻¹ for H. tubifera and S. plicata, respectively. In the presence of K. brevis, clearance rates of Rhodomonas sp. by B. neritina and S. plicata were depressed by 75% and 69%, respectively, while clearance rates by H. tubifera and M. mercenaria were unaffected. Negative effects of K. brevis were impermanent; after a recovery period of 13 h, B. neritina and S. plicata regained normal clearance rates. All four invertebrates accumulated high concentrations of brevetoxin after a 4h exposure to K. brevis, but when animals were transferred to filtered seawater for 15 h after exposure, brevetoxin concentrations in the tissues of H. tubifera and B. neritina decreased by ∼80%, while there was no change in toxin concentration in the tissues of S. plicata and M. mercenaria. High cell concentrations of K. brevis may cause a suppression of clearance rates in benthic suspension feeding invertebrates, resulting in a positive feedback for bloom formation. Also, high concentrations of toxin may accumulate in the tissues of benthic suspension feeding invertebrates that may

  13. Characterization of tamulamides A and B, polyethers isolated from the marine dinoflagellate Karenia brevis.

    PubMed

    Truxal, Laura T; Bourdelais, Andrea J; Jacocks, Henry; Abraham, William M; Baden, Daniel G

    2010-04-23

    Florida red tides occur as the result of blooms of the marine dinoflagellate Karenia brevis. K. brevis is known to produce several families of fused polyether ladder compounds. The most notable compounds are the brevetoxins, potent neurotoxins that activate mammalian sodium channels. Additional fused polyether ladder compounds produced by K. brevis include brevenal, brevisin, and hemibrevetoxin B, all with varying affinities for the same binding site on voltage-sensitive sodium channels. The structure elucidation and biological activity of two additional fused polyether ladder compounds containing seven fused ether rings will be described in this paper. Tamulamide A (MW = 638.30) and tamulamide B (MW = 624.29) were isolated from K. brevis cultures, and their structures elucidated using a combination of NMR spectroscopy and high-resolution mass spectrometry. Tamulamides A and B were both found to compete with tritiated brevetoxin-3 ([(3)H]-PbTx-3) for its binding site on rat brain synaptosomes. However, unlike the brevetoxins, tamulamides A and B showed no toxicity to fish at doses up to 200 nM and did not cause significant bronchoconstriction in sheep pulmonary assays.

  14. Vertical migration of Karenia brevis in the northeastern Gulf of Mexico observed from glider measurements.

    PubMed

    Hu, Chuanmin; Barnes, Brian B; Qi, Lin; Lembke, Chad; English, David

    2016-09-01

    The toxic marine dinoflagellate, Karenia brevis (the species responsible for most of red tides or harmful algal blooms in the Gulf of Mexico), is known to be able to swim vertically to adapt to the light and nutrient environments, nearly all such observations have been made through controlled experiments using cultures. Here, using continuous 3-dimensional measurements by an ocean glider across a K. brevis bloom in the northeastern Gulf of Mexico between 1 and 8 August 2014, we show the vertical migration behavior of K. brevis. Within the bloom where K. brevis concentration is between 100,000 and 1,000,000cellsL(-1), the stratified water shows a two-layer system with the depth of pycnocline ranging between 14-20m and salinity and temperature in the surface layer being <34.8 and >28°C, respectively. The bottom layer shows the salinity of >36 and temperature of <26°C. The low salinity is apparently due to coastal runoff, as the top layer also shows high amount of colored dissolved organic matter (CDOM). Within the top layer, chlorophyll-a fluorescence shows clear diel changes in the vertical structure, an indication of K. brevis vertical migration at a mean speed of 0.5-1mh(-1). The upward migration appears to start at sunrise at a depth of 8-10m, while the downward migration appears to start at sunset (or when surface light approaches 0) at a depth of ∼2m. These vertical migrations are believed to be a result of the need of K. brevis cells for light and nutrients in a stable, stratified, and CDOM-rich environment.

  15. BIOCHEMISTRY OF DINOFLAGELLATE LIPIDS, WITH PARTICULAR REFERENCE TO THE FATTY ACID AND STEROL COMPOSITION OF A KARENIA BREVIS BLOOM

    EPA Science Inventory

    Leblond, Jeffrey D., Terence J. Evens and Peter J. Chapman. 2003. Biochemistry of Dinoflagellate Lipids, with Particular Reference to the Fatty Acid and Sterol Composition of a Karenia brevis Bloom. Phycologia. 42(4):324-331. (ERL,GB 1160).

    The harmful marine dinoflagella...

  16. Osmotic stress does not trigger brevetoxin production in the dinoflagellate Karenia brevis

    PubMed Central

    Sunda, William G.; Burleson, Cheska; Hardison, D. Ransom; Morey, Jeanine S.; Wang, Zhihong; Wolny, Jennifer; Corcoran, Alina A.; Flewelling, Leanne J.; Van Dolah, Frances M.

    2013-01-01

    With the global proliferation of toxic harmful algal bloom species, there is a need to identify the environmental and biological factors that regulate toxin production. One such species, Karenia brevis, forms nearly annual blooms that threaten coastal regions throughout the Gulf of Mexico. This dinoflagellate produces brevetoxins, which are potent neurotoxins that cause neurotoxic shellfish poisoning and respiratory illness in humans, as well as massive fish kills. A recent publication reported that a rapid decrease in salinity increased cellular toxin quotas in K. brevis and hypothesized that brevetoxins serve a role in osmoregulation. This finding implied that salinity shifts could significantly alter the toxic effects of blooms. We repeated the original experiments separately in three different laboratories and found no evidence for increased brevetoxin production in response to low-salinity stress in any of the eight K. brevis strains we tested, including three used in the original study. Thus, we find no support for an osmoregulatory function of brevetoxins. The original publication also stated that there was no known cellular function for brevetoxins. However, there is increasing evidence that brevetoxins promote survival of the dinoflagellates by deterring grazing by zooplankton. Whether they have other as-yet-unidentified cellular functions is currently unknown. PMID:23754363

  17. NITROGEN LIMITATION INCREASES BREVETOXINS IN KARENIA BREVIS (DINOPHYCEAE): IMPLICATIONS FOR BLOOM TOXICITY(1).

    PubMed

    Ransom Hardison, D; Sunda, William G; Wayne Litaker, R; Shea, Damian; Tester, Patricia A

    2012-08-01

    Laboratory and field measurements of the toxin content in Karenia brevis cells vary by >4-fold. These differences have been largely attributed to genotypic variations in toxin production among strains. We hypothesized that nutrient limitation of growth rate is equally or more important in controlling the toxicity of K. brevis, as has been documented for other toxic algae. To test this hypothesis, we measured cellular growth rate, chlorophyll a, cellular carbon and nitrogen, cell volume, and brevetoxins in four strains of K. brevis grown in nutrient-replete and nitrogen (N)-limited semi-continuous cultures. N-limitation resulted in reductions of chlorophyll a, growth rate, volume per cell and nirtogen:carbon (N:C) ratios as well as a two-fold increase (1%-4% to 5%-9%) in the percentage of cellular carbon present as brevetoxins. The increase in cellular brevetoxin concentrations was consistent among genetically distinct strains. Normalizing brevetoxins to cellular volume instead of per cell eliminated much of the commonly reported toxin variability among strains. These results suggest that genetically linked differences in cellular volume may affect the toxin content of K. brevis cells as much or more than innate genotypic differences in cellular toxin content per unit of biomass. Our data suggest at least some of the >4-fold difference in toxicity per cell reported from field studies can be explained by limitation by nitrogen or other nutrients and by differences in cell size. The observed increase in brevetoxins in nitrogen limited cells is consistent with the carbon:nutrient balance hypothesis for increases in toxins and other plant defenses under nutrient limitation.

  18. A filterable lytic agent obtained from a red tide bloom that caused lysis of Karenia brevis (Gymnodinum breve) cultures

    USGS Publications Warehouse

    2002-01-01

    A filterable lytic agent (FLA) was obtained from seawater in the southeastern Gulf of Mexico during a red tide bloom that caused lysis of Karenia brevis (formerly Gymnodinium breve) Piney Island. This agent was obtained from <0.2µ  filtrates that were concentrated by ultrafiltration using a 100 kDa filter. The FLA was propagated by passage on K. brevis cultures, and the filtered supernatants of such cultures resulted in K. brevis lysis when added to such cultures. The lytic activity was lost upon heating to 65°C or by 0.02 µm filtration. Epifluorescence and transmission electron microscopy (TEM) of supernatants of K. brevis cultures treated with the lytic agent indicated a high abundance of viral particles (4 × 109 to 7 × 109 virus-like particles [VLPs] ml–1) compared to control cultures (~107 ml–1). However, viral particles were seldom found in TEM photomicrograph thin sections of lysing K. brevis cells. Although a virus specific for K. brevis may have been the FLA, other explanations such as filterable bacteria or bacteriophages specific for bacteria associated with the K. brevis cultures cannot be discounted.

  19. Inhibitory effects and oxidative target site of dibutyl phthalate on Karenia brevis.

    PubMed

    Li, Feng-min; Wu, Miao; Yao, Yuan; Zheng, Xiang; Zhao, Jian; Wang, Zhen-yu; Xing, Bao-shan

    2015-08-01

    The inhibitory action and possible damage mechanism of dibutyl phthalate (DBP) on the red tide algae Karenia brevis were investigated. The results showed that the algae experienced oxidative stress after exposure to 5mgL(-1) DBP. Malondialdehyde (MDA) peaked after 72h, with a value approximately 2.3 times higher than that observed for untreated cells. The superoxide dismutase (SOD) and catalase (CAT) activities significantly increased as an adaptive reaction after 48h. DBP induced the overproduction of reactive oxygen species (ROS), the OH concentration showed a peak of 33UmL(-1) at 48h, and the highest H2O2 content was approximately 250nmol/10(7) cells at 72h; these latter two values were 2.5 and 4.4 times higher than observed for the control, respectively. TEM images showed that a number of small vacuoles or apical tubers were commonly found around the cell membrane, and the membrane structure was ultimately disintegrated. Further experiments were carried out to locate the original ROS production sites following DBP exposure. The activity of CuZn-SOD (a mainly cytosolic isoform, with some also found in chloroplasts) under DBP exposure was approximately 2.5 times higher than the control, whereas the Mn-SOD (mitochondrial isoform) activity was significantly inhibited. No significant difference was observed in the activity of Fe-SOD (chloroplastic isoform). In addition, dicumarol (an inhibitor of the electron transport chain in the plasma membrane) stimulated DBP-induced ROS production, whereas rotenone (an inhibitor of the mitochondria electron transport chain complex I) decreased DBP-induced ROS production. These results suggested that mitochondria could be the main target sites for DBP attack.

  20. Susceptibility of gametes and embryos of the eastern oyster, Crassostrea virginica, to Karenia brevis and its toxins.

    PubMed

    Rolton, Anne; Soudant, Philippe; Vignier, Julien; Pierce, Richard; Henry, Michael; Shumway, Sandra E; Bricelj, V Monica; Volety, Aswani K

    2015-06-01

    The bivalve mollusc, Crassostrea virginica, is frequently exposed to blooms of Karenia brevis along the west coast of Florida during periods of spawning and early larval development. A continuous 4-day exposure of gametes and 2-4 cell stage embryos of C. virginica to whole-cell and culture filtrate of K. brevis at 500 and 5000 cells mL(-1), was followed by a 4-day 'recovery' period. Larval growth, percent of normal, abnormal and dead larvae, and the presence of food in the larval gut were measured throughout the exposure period. Results suggest that negative effects mainly occur during embryogenesis and early development. Damage to feeding apparatus/gut may occur during embryonic development or exposure to toxins may act as a feeding deterrent on non-toxic algae. Following 2-h in vitro exposure of gametes, differences in oocyte and sperm cell parameters were investigated using flow cytometry. The reduced sperm viability in the whole-cell 5000 cells mL(-1) treatment suggests the involvement of extracellular brevetoxins (PbTx) and perhaps other harmful, uncharacterized compounds associated with the K. brevis cell membrane. The cumulative effects of reduced sperm viability, fertilization success, embryonic and larval survival, and the near-annual exposure to blooms of K. brevis could cause significant bottlenecks on oyster recruitment.

  1. A NUMERICAL ANALYSIS OF LANDFALL OF THE 1979 RED TIDE OF KARENIA BREVIS ALONG THE WEST COAST OF FLORIDA. (R827085)

    EPA Science Inventory

    Abstract

    A simple ecological model, coupled to a primitive equation circulation model, is able to replicate the observed alongshore transport of the toxic dinoflagellate Karenia brevis on the West Florida shelf during a fall red tide in 1979. Initial land fall o...

  2. The toxic dinoflagellate Karenia brevis encodes novel type I-like polyketide synthases containing discrete catalytic domains.

    PubMed

    Monroe, Emily A; Van Dolah, Frances M

    2008-07-01

    Karenia brevis is the Florida red tide dinoflagellate responsible for detrimental effects on human and environmental health through the production of brevetoxins. Brevetoxins are thought to be synthesized by a polyketide synthase (PKS) complex, but the gene cluster for this PKS has yet to be identified. Here, eight PKS transcripts were identified in K. brevis by high throughput cDNA library screening. Full length sequences were obtained through 3' and 5' RACE, which demonstrated the presence of polyadenylation, 3'-UTRs, and an identical dinoflagellate-specific spliced leader sequence at the 5' end of PKS transcripts. Six transcripts encoded for individual ketosynthase (KS) domains, one ketoreductase (KR), and one transcript encoded both acyl carrier protein (ACP) and KS domains. Transcript lengths ranged from 1875 to 3397 nucleotides, based on sequence analysis, and were confirmed by northern blotting. Baysian phylogenetic analysis of the K. brevis KS domains placed them well within the protist type I PKS clade. Thus although most similar to type I modular PKSs, the presence of individual catalytic domains on separate transcripts suggests a protein structure more similar to type II PKSs, in which each catalytic domain resides on an individual protein. These results identify an unprecedented PKS structure in a toxic dinoflagellate.

  3. Neural network retrievals of Karenia brevis harmful algal blooms in the West Florida Shelf (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Ahmed, Samir; El-Habashi, Ahmed

    2016-10-01

    Effective detection and tracking of Karenia brevis Harmful Algal Blooms (KB HAB) that frequently plague the coasts and beaches of the West Florida Shelf (WFS) is important because of their negative impacts on ecology. They pose threats to fisheries, human health, and directly affect tourism and local economies. Detection and tracking capabilities are needed for use with the Visible Infrared Imaging Radiometer Suite (VIIRS) satellite, so that HABs monitoring capabilities, which previously relied on imagery from the Moderate Resolution Imaging Spectroradiometer Aqua, can be extended to VIIRS. Unfortunately, VIIRS, unlike its predecessor MODIS-A, does not have a 678 nm channel to detect chlorophyll fluorescence, which is used in the normalized fluorescence height (nFLH) algorithm, or in the Red Band Difference (RBD) algorithm. Both these techniques have demonstrated that the remote sensing reflectance signal from the MODIS-A fluorescence band (Rrs 678 nm) helps in effectively detecting and tracking KB HABs in the WFS. To overcome the lack of a fluorescence channel on VIIRS, the approach described here, bypasses the need for measurements at 678nm, and permits extension of KB HABs satellite monitoring to VIIRS. The essence of the approach is the application of a standard multiband neural network (NN) inversion algorithm, previously developed and reported by us, that takes VIIRS Rrs measurements at the 486, 551 and 671nm bands as inputs, and produces as output the related Inherent Optical Properties (IOPs), namely: absorption coefficients of phytoplankton (aph443) dissolved organic matter (ag) and non-algal particulates (adm) as well as the particulate backscatter coefficient, (bbp) all at 443nm. We next need to relate aph443 in the VIIRS NN retrieved image to equivalent KB HABs concentrations. To do this, we apply additional constraints, defined by (i) low backscatter manifested as a maximum Rrs551 value and (ii) a minimum [Chla] threshold (and hence an equivalent

  4. Net community production and dark community respiration in a Karenia brevis (Davis) bloom in West Florida coastal waters, USA.

    PubMed

    Hitchcock, Gary L; Kirkpatrick, Gary; Minnett, Peter; Palubok, Valeriy

    2010-05-01

    Oxygen-based productivity and respiration rates were determined in West Florida coastal waters to evaluate the proportion of community respiration demands met by autotrophic production within a harmful algal bloom dominated by Karenia brevis. The field program was adaptive in that sampling during the 2006 bloom occurred where surveys by the Florida Wildlife Research Institute indicated locations with high cell abundances. Net community production (NCP) rates from light-dark bottle incubations during the bloom ranged from 10 to 42 µmole O2 L(-1) day(-1) with highest rates in bloom waters where abundances exceeded 10(5) cells L(-1). Community dark respiration (R) rates in dark bottles ranged from <10 to 70 µmole O2 L(-1) day(-1) over 24 h. Gross primary production derived from the sum of NCP and R varied from ca. 20 to 120 µmole O2 L(-1) day(-1). The proportion of GPP attributed to NCP varied with the magnitude of R during day and night periods. Most surface communities exhibited net autotrophic production (NCP > R) over 24 h, although heterotrophy (NCP < R) characterized the densest sample where K. brevis cell densities exceed 10(6) cells L(-1).

  5. Net community production and dark community respiration in a Karenia brevis (Davis) bloom in West Florida coastal waters, USA

    PubMed Central

    Hitchcock, Gary L.; Kirkpatrick, Gary; Minnett, Peter; Palubok, Valeriy

    2013-01-01

    Oxygen-based productivity and respiration rates were determined in West Florida coastal waters to evaluate the proportion of community respiration demands met by autotrophic production within a harmful algal bloom dominated by Karenia brevis. The field program was adaptive in that sampling during the 2006 bloom occurred where surveys by the Florida Wildlife Research Institute indicated locations with high cell abundances. Net community production (NCP) rates from light-dark bottle incubations during the bloom ranged from 10 to 42 µmole O2 L−1 day−1 with highest rates in bloom waters where abundances exceeded 105 cells L−1. Community dark respiration (R) rates in dark bottles ranged from <10 to 70 µmole O2 L−1 day−1 over 24 h. Gross primary production derived from the sum of NCP and R varied from ca. 20 to 120 µmole O2 L−1 day−1. The proportion of GPP attributed to NCP varied with the magnitude of R during day and night periods. Most surface communities exhibited net autotrophic production (NCP > R) over 24 h, although heterotrophy (NCP < R) characterized the densest sample where K. brevis cell densities exceed 106 cells L−1. PMID:24179460

  6. Global Analysis of mRNA Half-Lives and de novo Transcription in a Dinoflagellate, Karenia brevis

    PubMed Central

    Morey, Jeanine S.; Van Dolah, Frances M.

    2013-01-01

    Dinoflagellates possess many physiological processes that appear to be under post-transcriptional control. However, the extent to which their genes are regulated post-transcriptionally remains unresolved. To gain insight into the roles of differential mRNA stability and de novo transcription in dinoflagellates, we biosynthetically labeled RNA with 4-thiouracil to isolate newly transcribed and pre-existing RNA pools in Karenia brevis. These isolated fractions were then used for analysis of global mRNA stability and de novo transcription by hybridization to a K. brevis microarray. Global K. brevis mRNA half-lives were calculated from the ratio of newly transcribed to pre-existing RNA for 7086 array features using the online software HALO (Half-life Organizer). Overall, mRNA half-lives were substantially longer than reported in other organisms studied at the global level, ranging from 42 minutes to greater than 144 h, with a median of 33 hours. Consistent with well-documented trends observed in other organisms, housekeeping processes, including energy metabolism and transport, were significantly enriched in the most highly stable messages. Shorter-lived transcripts included a higher proportion of transcriptional regulation, stress response, and other response/regulatory processes. One such family of proteins involved in post-transcriptional regulation in chloroplasts and mitochondria, the pentatricopeptide repeat (PPR) proteins, had dramatically shorter half-lives when compared to the arrayed transcriptome. As transcript abundances for PPR proteins were previously observed to rapidly increase in response to nutrient addition, we queried the newly synthesized RNA pools at 1 and 4 h following nitrate addition to N-depleted cultures. Transcriptome-wide there was little evidence of increases in the rate of de novo transcription during the first 4 h, relative to that in N-depleted cells, and no evidence for increased PPR protein transcription. These results lend support to

  7. Karenia brevis blooms on the West Florida Shelf: A comparative study of the robust 2012 bloom and the nearly null 2013 event

    NASA Astrophysics Data System (ADS)

    Weisberg, Robert H.; Zheng, Lianyuan; Liu, Yonggang; Corcoran, Alina A.; Lembke, Chad; Hu, Chuanmin; Lenes, Jason M.; Walsh, John J.

    2016-06-01

    Harmful algal blooms of the dinoflagellate Karenia brevis require an upwelling circulation to manifest along the coastline of the West Florida Continental Shelf. Too much upwelling, however, can impede bloom formation by increasing inorganic nutrient levels to the point where faster growing phytoplankton such as diatoms may out-compete the slower growing K. brevis, as occurred in 1998 and 2010. Both 2012 and 2013 experienced persistent upwelling, but only 2012 exhibited a robust harmful algal bloom. Here we examine the subtle differences in the coastal ocean circulation between those two years that led to the disparate bloom evolutions.

  8. A physical and biological context for Karenia brevis seed populations on the northwest Florida shelf during July 2009

    NASA Astrophysics Data System (ADS)

    McCulloch, Anita A.; Kamykowski, Daniel; Morrison, John M.; Thomas, Carrie J.; Pridgen, Katy Grabowski

    2013-07-01

    The current effort focuses on characterizing physical and biological conditions across the northwest Florida shelf during summer as they influence Karenia brevis distributions and phytoplankton/microphytobenthos community associations. Phytoplankton and benthic algal communities were examined in the context of cross-shelf hydrography and sediment conditions during July 2009 between the 20 and 65 m isobaths off Panama City, FL. A towed undulating profiler (SeaSciences Acrobat) mapped water column characteristics between near-surface and ˜1 m above the sediment. A CTD/rosette provided hydrographic profiles and collected water samples at 17 cross-shelf locations at selected depths for nutrient concentration, phytoplankton biomass determination, and chemotaxonomic and taxonomic phytoplankton identification. In addition, a CTD/rosette time series sample set was collected following a holey sock drogue set at ˜34 m along the ˜50 m isobath, and cores were collected at eight stations approximately along the 30, 40 and 55 m isobaths. Cross-shelf, a pycnocline existed at ˜10 m depth, the 1% light level penetrated to ˜45 m depth, and nitrate-nitrite (NO3-+NO2-) concentrations increased in the lower 10 m of the water column to the 50 m isobath and then below 40-m depth to the 65 m isobath. A chlorophyll a peak occurred near-bottom between the 25 and 35 m isobaths. Gyroxanthin dinoflagellates (GD) representing K. brevis occurred across the shelf in near-surface and near-bottom waters. Near-surface GD co-occurred with cyanophytes at low density in the upper 20 m of the water column where NO3-+NO2- concentrations were low. Above sediments in the euphotic zone, near-bottom GD were most abundant between the 25 and 35 m isobaths where the NO3-+NO2- concentrations were 1-4 µM and where microphytobenthos competed for nutrient sources. Below the euphotic zone, GD were present near-bottom to the 60 m isobath where NO3-+NO2- concentrations approached 6 µM. A pattern consistent with

  9. A competitive ELISA to detect brevetoxins from Karenia brevis (formerly Gymnodinium breve) in seawater, shellfish, and mammalian body fluid.

    PubMed Central

    Naar, Jerome; Bourdelais, Andrea; Tomas, Carmelo; Kubanek, Julia; Whitney, Philip L; Flewelling, Leanne; Steidinger, Karen; Lancaster, Johnny; Baden, Daniel G

    2002-01-01

    We developed a competitive enzyme-linked immunosorbent assay (ELISA) to analyze brevetoxins, using goat anti-brevetoxin antibodies obtained after immunization with keyhole limpet hemocyanin-brevetoxin conjugates, in combination with a three-step signal amplification process. The procedure, which used secondary biotinylated antibodies, streptavidine-horseradish peroxidase conjugate, and chromogenic enzyme substrate, was useful in reducing nonspecific background signals commonly observed with complex matrices. This competitive ELISA detected brevetoxins in seawater, shellfish extract and homogenate, and mammalian body fluid such as urine and serum without pretreatment, dilution, or purification. We investigated the application of this technique for shellfish monitoring by spiking shellfish meat with brevetoxins and by analyzing oysters from two commercial shellfish beds in Florida that were exposed to a bloom of Karenia brevis (formerly Gymnodinium breve). We performed brevetoxin analysis of shellfish extracts and homogenates by ELISA and compared it with the mouse bioassay and receptor binding assay. The detection limit for brevetoxins in spiked oysters was 2.5 microg/100 g shellfish meat. This assay appears to be a useful tool for neurotoxic shellfish poisoning monitoring in shellfish and seawater, and for mammalian exposure diagnostics, and significantly reduces the time required for analyses. PMID:11836147

  10. Characterization and localization of a hybrid non-ribosomal peptide synthetase and polyketide synthase gene from the toxic dinoflagellate Karenia brevis.

    PubMed

    López-Legentil, Susanna; Song, Bongkeun; DeTure, Michael; Baden, Daniel G

    2010-02-01

    The toxic dinoflagellate Karenia brevis, a causative agent of the red tides in Florida, produces a series of toxic compounds known as brevetoxins and their derivatives. Recently, several putative genes encoding polyketide synthase (PKS) were identified from K. brevis in an effort to elucidate the genetic systems involved in brevetoxin production. In this study, novel PKS sequences were isolated from three clones of K. brevis. Eighteen unique sequences were obtained for the PKS ketosynthase (KS) domain of K. brevis. Phylogenetic comparison with closely related PKS genes revealed that 16 grouped with cyanobacteria sequences, while the remaining two grouped with Apicomplexa and previously reported sequences for K. brevis. A fosmid library was also constructed to further characterize PKS genes detected in K. brevis Wilson clone. Several fosmid clones were positive for the presence of PKS genes, and one was fully sequenced to determine the full structure of the PKS cluster. A hybrid non ribosomal peptide synthetase and PKS (NRPS-PKS) gene cluster of 16,061 bp was isolated. In addition, we assessed whether the isolated gene was being actively expressed using reverse transcription polymerase chain reaction (RT-PCR) and determined its localization at the cellular level by chloroplast isolation. RT-PCR analyses revealed that this gene was actively expressed in K. brevis cultures. The hybrid NRPS-PKS gene cluster was located in the chloroplast, suggesting that K. brevis acquired the ability to produce some of its secondary metabolites through endosymbiosis with ancestral cyanobacteria. Further work is needed to determine the compound produced by the NRPS-PKS hybrid, to find other PKS gene sequences, and to assess their role in K. brevis toxin biosynthetic pathway.

  11. A harmful algal bloom of Karenia brevis in the northeastern Gulf of Mexico as revealed by MODIS and VIIRS: a comparison.

    PubMed

    Hu, Chuanmin; Barnes, Brian B; Qi, Lin; Corcoran, Alina A

    2015-01-28

    The most recent Visible Infrared Imager Radiometer Suite (VIIRS) is not equipped with a spectral band to detect solar-stimulated phytoplankton fluorescence. The lack of such a band may affect the ability of VIIRS to detect and quantify harmful algal blooms (HABs) in coastal waters rich in colored dissolved organic matter (CDOM) because of the overlap of CDOM and chlorophyll absorption within the blue-green spectrum. A recent HAB dominated by the toxin-producing dinoflagellate Karenia brevis in the northeastern Gulf of Mexico, offshore of Florida's Big Bend region, allowed for comparison of the capacities of VIIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) to detect blooms in CDOM-rich waters. Both VIIRS and MODIS showed general consistency in mapping the CDOM-rich dark water, which measured a maximum area of 8900 km2 by mid-July 2014. However, within the dark water, only MODIS allowed detection of bloom patches-as indicated by high normalized fluorescence line height (nFLH). Field surveys between late July and mid-September confirmed Karenia brevis at bloom abundances up to 20 million cells·L(-1) within these patches. The bloom patches were well captured by the MODIS nFLH images, but not by the default chlorophyll a concentration (Chla) images from either MODIS or VIIRS. Spectral analysis showed that VIIRS could not discriminate these high-phytoplankton water patches within the dark water due to its lack of fluorescence band. Such a deficiency may be overcome with new algorithms or future satellite missions such as the U.S. NASA's Pre-Aerosol-Clouds-Ecology mission and the European Space Agency's Sentinel-3 mission.

  12. A Harmful Algal Bloom of Karenia brevis in the Northeastern Gulf of Mexico as Revealed by MODIS and VIIRS: A Comparison

    PubMed Central

    Hu, Chuanmin; Barnes, Brian B.; Qi, Lin; Corcoran, Alina A.

    2015-01-01

    The most recent Visible Infrared Imager Radiometer Suite (VIIRS) is not equipped with a spectral band to detect solar-stimulated phytoplankton fluorescence. The lack of such a band may affect the ability of VIIRS to detect and quantify harmful algal blooms (HABs) in coastal waters rich in colored dissolved organic matter (CDOM) because of the overlap of CDOM and chlorophyll absorption within the blue-green spectrum. A recent HAB dominated by the toxin-producing dinoflagellate Karenia brevis in the northeastern Gulf of Mexico, offshore of Florida's Big Bend region, allowed for comparison of the capacities of VIIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) to detect blooms in CDOM-rich waters. Both VIIRS and MODIS showed general consistency in mapping the CDOM-rich dark water, which measured a maximum area of 8900 km2 by mid-July 2014. However, within the dark water, only MODIS allowed detection of bloom patches—as indicated by high normalized fluorescence line height (nFLH). Field surveys between late July and mid-September confirmed Karenia brevis at bloom abundances up to 20 million cells·L−1 within these patches. The bloom patches were well captured by the MODIS nFLH images, but not by the default chlorophyll a concentration (Chla) images from either MODIS or VIIRS. Spectral analysis showed that VIIRS could not discriminate these high-phytoplankton water patches within the dark water due to its lack of fluorescence band. Such a deficiency may be overcome with new algorithms or future satellite missions such as the U.S. NASA's Pre-Aerosol-Clouds-Ecology mission and the European Space Agency's Sentinel-3 mission. PMID:25635412

  13. A 1-D simulation analysis of the development and maintenance of the 2001 red tide of the ichthyotoxic dinoflagellate Karenia brevis on the West Florida shelf

    NASA Astrophysics Data System (ADS)

    Lenes, J. M.; Darrow, B. P.; Walsh, J. J.; Jolliff, J. K.; Chen, F. R.; Weisberg, R. H.; Zheng, L.

    2012-06-01

    A one-dimensional (1-D) ecological model, HABSIM, examined the initiation and maintenance of the 2001 red tide on the West Florida shelf (WFS). Phytoplankton competition among toxic dinoflagellates (Karenia brevis), nitrogen fixing cyanophytes (Trichodesmium erythraeum), large siliceous phytoplankton (diatoms), and small non-siliceous phytoplankton (microflagellates) explored the sequence of events required to support the observed red tide from August to December 2001. The ecological model contained 24 state variables within five submodels: circulation, atmospheric (iron deposition), bio-optics, pelagic (phytoplankton, nutrients, bacteria, zooplankton, and fish), and benthic (nutrient regeneration). The 2001 model results reaffirmed that diazotrophs are the basis for initiation of red tides of K. brevis on the WFS. A combination of selective grazing pressure, iron fertilization, low molar nitrogen to phosphorus ratios, and eventual silica limitation of fast-growing diatoms set the stage for dominance of nitrogen fixers. "New" nitrogen was made available for subsequent blooms of K. brevis through the release of ammonium and urea during nitrogen fixation, as well as during cell lysis, by the Trichodesmium population. Once K. brevis biomass reached ichthyotoxic levels, rapid decay of subsequent fish kills supplied additional organic nutrients for utilization by these opportunistic toxic algae. Both nutrient vectors represented organic non-siliceous sources of nitrogen and phosphorus, further exacerbating silica limitation of the diatom population. The model reproduced this spring transition from a simple estuarine-driven, diatom-based food chain to a complex summer-fall system of Trichodesmium and toxic dinoflagellates. While the model was able to replicate the initiation and maintenance of the 2001 red tide, bloom termination was not captured by this 1-D form on the WFS. Here, horizontal advection and perhaps cell lysis loss terms might play a significant role, to be

  14. A three-dimensional biophysical model of Karenia brevis dynamics on the west Florida shelf: A look at physical transport and potential zooplankton grazing controls

    NASA Astrophysics Data System (ADS)

    Milroy, Scott P.; Dieterle, Dwight A.; He, Ruoying; Kirkpatrick, Gary J.; Lester, Kristen M.; Steidinger, Karen A.; Vargo, Gabriel A.; Walsh, John J.; Weisberg, Robert H.

    2008-01-01

    The development of accurate predictive models of toxic dinoflagellate blooms is of great ecological importance, particularly in regions that are most susceptible to their detrimental effects. This is especially true along the west Florida shelf (WFS) and coast, where episodic bloom events of the toxic dinoflagellate Karenia brevis often wreak havoc on the valuable commercial fisheries and tourism industries of west Florida. In an effort to explain the dynamics at work within the maintenance and termination phases of a red tide, a simple three-dimensional coupled biophysical model was used in the analysis of the October 1999 red tide offshore Sarasota, Florida. Results of the numerical experiments indicate that: (1) measured and modeled flowfields were capable of transporting the observed offshore inoculum of K. brevis to within 16 km of the coastal boundary; (2) background concentrations (1000 cells L -1) of K. brevis could grow to a red tide of over 2×10 6 cells L -1 in little more than a month, assuming an estuarine initiation site with negligible offshore advection, no grazing losses, negligible competition from other phytoplankton groups, and no nutrient limitation; (3) maximal grazing pressure could not prevent the initiation of a red tide or cause its termination, assuming no other losses to algal biomass and a zooplankton community ingestion rate similar to that of Acartia tonsa; and (4) the light-cued ascent behavior of K. brevis served as an aggregational mechanism, concentrating K. brevis at the 55 μE m -2 s -1 isolume when mean concentrations of K. brevis exceeded 100,000 cells L -1. Further improvements in model fidelity will be accomplished by the future inclusion of phytoplankton competitors, disparate nutrient availability and limitation schemes, a more realistic rendering of the spectral light field and the attendant effects of photo-inhibition and compensation, and a mixed community of vertically-migrating proto- and metazoan grazers. These model

  15. Fate and distribution of brevetoxin (PbTx) following lysis of Karenia brevis by algicidal bacteria, including analysis of open A-ring derivatives.

    PubMed

    Roth, Patricia B; Twiner, Michael J; Wang, Zhihong; Bottein Dechraoui, Marie-Yasmine; Doucette, Gregory J

    2007-12-15

    Flavobacteriaceae (strain S03) and Cytophaga sp. (strain 41-DBG2) are algicidal bacteria active against the brevetoxin (PbTx)-producing, red tide dinoflagellate, Karenia brevis. Little is known about the fate of PbTx associated with K. brevis cells following attack by such bacteria. The fate and distribution of PbTx in K. brevis cultures exposed to these algicidal strains were thus examined by receptor binding assay and liquid chromatography/mass spectrometry (LC/MS) in three size fractions (>5, 0.22-5, <0.22microm) over a 2-week time course. In control cultures, brevetoxin concentrations in the >5microm particulate size fraction correlated with changes in cell density, whereas significant increases in dissolved (i.e., <0.22microm) toxin were observed in the later stages of culture growth. Exposure of K. brevis to either of the two algicidal bacteria tested caused cell lysis, coinciding with a rapid decline in the >5microm PbTX size fraction and a simultaneous release of dissolved toxin into the growth medium. Upon cell lysis, dissolved brevetoxin accounted for ca. 60% of total toxin and consisted of 51-82% open A-ring derivatives. Open A-ring PbTx-2 and PbTx-3 derivatives bound with lower affinity (approximately 22- and 57-fold, respectively) to voltage-gated sodium channels and were considerably less cytotoxic (86- and 142-fold, respectively) to N2A cells than their individual parent toxins (i.e., PbTx-2 and PbTx-3). These novel findings of changes in PbTx size-fractioned distribution and overall reduction in K. brevis toxicity following attack by algicidal bacteria improve our understanding of potential trophic transfer routes and the fate of PbTx during red tide events. Moreover, this information will be important to consider when evaluating the potential role of algicidal bacteria in harmful algal bloom (HAB) management strategies involving control of bloom populations.

  16. Coyote (Canis latrans) and domestic dog (Canis familiaris) mortality and morbidity due to a Karenia brevis red tide in the Gulf of Mexico.

    PubMed

    Castle, Kevin T; Flewelling, Leanne J; Bryan, John; Kramer, Adam; Lindsay, James; Nevada, Cheyenne; Stablein, Wade; Wong, David; Landsberg, Jan H

    2013-10-01

    In October 2009, during a Karenia brevis red tide along the Texas coast, millions of dead fish washed ashore along the 113-km length of Padre Island National Seashore (PAIS). Between November 2009 and January 2010, at least 12 coyotes (Canis latrans) and three domestic dogs (Canis familiaris) died or were euthanized at PAIS or local veterinary clinics because of illness suspected to be related to the red tide. Another red tide event occurred during autumn 2011 and, although fewer dead fish were observed relative to the 2009 event, coyotes again were affected. Staff at PAIS submitted carcasses of four coyotes and one domestic dog from November 2009 to February 2010 and six coyotes from October to November 2011 for necropsy and ancillary testing. High levels of brevetoxins (PbTxs) were measured by enzyme-linked immunosorbent assay in seven of the coyotes and the dog, with concentrations up to 634 ng PbTx-3 eq/g in stomach contents, 545 ng PbTx-3 eq/g in liver, 195 ng PbTx-3 eq/g in kidney, and 106 ng PbTx-3 eq/mL in urine samples. Based on red tide presence, clinical signs, and postmortem findings, brevetoxicosis caused by presumptive ingestion of toxic dead fish was the likely cause of canid deaths at PAIS. These findings represent the first confirmed report of terrestrial mammalian wildlife mortalities related to a K. brevis bloom. The implications for red tide impacts on terrestrial wildlife populations are a potentially significant but relatively undocumented phenomenon.

  17. Long-term evaluation of three satellite ocean color algorithms for identifying harmful algal blooms (Karenia brevis) along the west coast of Florida: A matchup assessment

    PubMed Central

    Carvalho, Gustavo A.; Minnett, Peter J.; Banzon, Viva F.; Baringer, Warner; Heil, Cynthia A.

    2011-01-01

    We present a simple algorithm to identify Karenia brevis blooms in the Gulf of Mexico along the west coast of Florida in satellite imagery. It is based on an empirical analysis of collocated matchups of satellite and in situ measurements. The results of this Empirical Approach is compared to those of a Bio-optical Technique – taken from the published literature – and the Operational Method currently implemented by the NOAA Harmful Algal Bloom Forecasting System for K. brevis blooms. These three algorithms are evaluated using a multi-year MODIS data set (from July, 2002 to October, 2006) and a long-term in situ database. Matchup pairs, consisting of remotely-sensed ocean color parameters and near-coincident field measurements of K. brevis concentration, are used to assess the accuracy of the algorithms. Fair evaluation of the algorithms was only possible in the central west Florida shelf (i.e. between 25.75°N and 28.25°N) during the boreal Summer and Fall months (i.e. July to December) due to the availability of valid cloud-free matchups. Even though the predictive values of the three algorithms are similar, the statistical measure of success in red tide identification (defined as cell counts in excess of 1.5 × 104 cells L−1) varied considerably (sensitivity—Empirical: 86%; Bio-optical: 77%; Operational: 26%), as did their effectiveness in identifying non-bloom cases (specificity—Empirical: 53%; Bio-optical: 65%; Operational: 84%). As the Operational Method had an elevated frequency of false-negative cases (i.e. presented low accuracy in detecting known red tides), and because of the considerable overlap between the optical characteristics of the red tide and non-bloom population, only the other two algorithms underwent a procedure for further inspecting possible detection improvements. Both optimized versions of the Empirical and Bio-optical algorithms performed similarly, being equally specific and sensitive (~70% for both) and showing low levels of

  18. Long-term evaluation of three satellite ocean color algorithms for identifying harmful algal blooms (Karenia brevis) along the west coast of Florida: A matchup assessment.

    PubMed

    Carvalho, Gustavo A; Minnett, Peter J; Banzon, Viva F; Baringer, Warner; Heil, Cynthia A

    2011-01-17

    We present a simple algorithm to identify Karenia brevis blooms in the Gulf of Mexico along the west coast of Florida in satellite imagery. It is based on an empirical analysis of collocated matchups of satellite and in situ measurements. The results of this Empirical Approach is compared to those of a Bio-optical Technique - taken from the published literature - and the Operational Method currently implemented by the NOAA Harmful Algal Bloom Forecasting System for K. brevis blooms. These three algorithms are evaluated using a multi-year MODIS data set (from July, 2002 to October, 2006) and a long-term in situ database. Matchup pairs, consisting of remotely-sensed ocean color parameters and near-coincident field measurements of K. brevis concentration, are used to assess the accuracy of the algorithms. Fair evaluation of the algorithms was only possible in the central west Florida shelf (i.e. between 25.75°N and 28.25°N) during the boreal Summer and Fall months (i.e. July to December) due to the availability of valid cloud-free matchups. Even though the predictive values of the three algorithms are similar, the statistical measure of success in red tide identification (defined as cell counts in excess of 1.5 × 10(4) cells L(-1)) varied considerably (sensitivity-Empirical: 86%; Bio-optical: 77%; Operational: 26%), as did their effectiveness in identifying non-bloom cases (specificity-Empirical: 53%; Bio-optical: 65%; Operational: 84%). As the Operational Method had an elevated frequency of false-negative cases (i.e. presented low accuracy in detecting known red tides), and because of the considerable overlap between the optical characteristics of the red tide and non-bloom population, only the other two algorithms underwent a procedure for further inspecting possible detection improvements. Both optimized versions of the Empirical and Bio-optical algorithms performed similarly, being equally specific and sensitive (~70% for both) and showing low levels of

  19. Diel Vertical Migration Thresholds of Karenia brevis (Dinophyceae).

    EPA Science Inventory

    Light and nutrient availability change throughout dinoflagellate diel vertical migration (DVM) and/or with subpopulation location in the water column along the west Florida shelf. Typically, the vertical depth of the shelf is greater than the distance a subpopulation can vertical...

  20. RNA Sequencing Revealed Numerous Polyketide Synthase Genes in the Harmful Dinoflagellate Karenia mikimotoi

    PubMed Central

    Kimura, Kei; Okuda, Shujiro; Nakayama, Kei; Shikata, Tomoyuki; Takahashi, Fumio; Yamaguchi, Haruo; Skamoto, Setsuko; Yamaguchi, Mineo; Tomaru, Yuji

    2015-01-01

    The dinoflagellate Karenia mikimotoi forms blooms in the coastal waters of temperate regions and occasionally causes massive fish and invertebrate mortality. This study aimed to elucidate the toxic effect of K. mikimotoi on marine organisms by using the genomics approach; RNA-sequence libraries were constructed, and data were analyzed to identify toxin-related genes. Next-generation sequencing produced 153,406 transcript contigs from the axenic culture of K. mikimotoi. BLASTX analysis against all assembled contigs revealed that 208 contigs were polyketide synthase (PKS) sequences. Thus, K. mikimotoi was thought to have several genes encoding PKS metabolites and to likely produce toxin-like polyketide molecules. Of all the sequences, approximately 30 encoded eight PKS genes, which were remarkably similar to those of Karenia brevis. Our phylogenetic analyses showed that these genes belonged to a new group of PKS type-I genes. Phylogenetic and active domain analyses showed that the amino acid sequence of four among eight Karenia PKS genes was not similar to any of the reported PKS genes. These PKS genes might possibly be associated with the synthesis of polyketide toxins produced by Karenia species. Further, a homology search revealed 10 contigs that were similar to a toxin gene responsible for the synthesis of saxitoxin (sxtA) in the toxic dinoflagellate Alexandrium fundyense. These contigs encoded A1–A3 domains of sxtA genes. Thus, this study identified some transcripts in K. mikimotoi that might be associated with several putative toxin-related genes. The findings of this study might help understand the mechanism of toxicity of K. mikimotoi and other dinoflagellates. PMID:26561394

  1. Brevibacillus brevis peritonitis.

    PubMed

    Parvez, Najma; Cornelius, Lisa K; Fader, Robert

    2009-04-01

    We present what we believe is the first case of Brevibacillus (Bacillus) brevis peritonitis in a patient with hepatocellular carcinoma, possibly caused by the ingestion of fermented foods containing B. brevis spores. This case also demonstrates a pattern of antibiotic susceptibility with differing in vitro and in vivo bactericidal efficacy.

  2. The cicada genus Karenia Distant, 1888 (Hemiptera: Cicadidae), with description of a new species.

    PubMed

    Pham, Hong-Thai; Constant, Jerome

    2014-08-19

    The cicadas of the genus Karenia are reviewed, and Karenia tibetensis sp.nov. (Hemiptera: Cicadidae) is described from Tibet, China. Pictures of the male adult and illustrations of the male genitalia are provided. A key to the species of Karenia is presented and the distribution of the Karenia species is discussed.

  3. Toxicity of clay flocculation of the toxic dinoflagellate, Karenia brevis, to estuarine invertebrates and fish

    EPA Science Inventory

    The benthic environmental effects of proposed control procedures for red tide events are relatively unknown but important to understand. The objective of this study was to determine the laboratory-derived toxicities of a clay flocculation technique proposed for the Florida red ti...

  4. Bioprospecting of Brevibacillus brevis isolated from soil.

    PubMed

    Samrot, Antony V; Prasad, Rejin J J; Rio, Antony J; Sneha, Sahaya J

    2015-01-01

    It is obviously essential to find new compounds that possess industrial and medicinal importance and potential to improve the lifestyle of human population. Bioprospecting these compounds from natural resources has additional benefits since they are less toxic as well as biocompatible. In this study, Brevibacillus brevis was isolated from soil and its enzymes production, antibacterial activity and anticancer activity were assessed. The organism was found to be a promising source of amylase enzymes, antibacterial as well as anticancer compounds.

  5. SURVEY OF THE STEROL COMPOSITION OF THE MARINE DINOFLAGELLATES KARENIA BREVIS, KARENIA MIKIMOTOI, AND KARLODINIUM MICRUM: DISTRIBUTION OF STEROLS WITHIN OTHER MEMBERS OF THE CLASS DINOPHYCEAE

    EPA Science Inventory

    The sterol composition of different marine microalgae was examined to determine the utility of sterols as biomarkers to distinguish members of various algal classes. For example, members of the class Dinophyceae possess certain 4-methyl sterols, such as dinosterol, which are rare...

  6. [Demodex folliculorum and demodex brevis].

    PubMed

    Marcinowska, Zuzanna; Kosik-Bogacka, Danuta; Lanocha-Arendarczyk, Natalia; Czepita, Damian; Lanocha, Aleksandra

    2015-01-01

    Demodex are cosmopolitan mites occurring in many species of mammals. Two morphologically distinct Demodex species parasitize on humans: Demodexfolliculorum (Simon, 1842) and Demodex brevis (Akbulatova, 1963). Until recently, these species have been regarded as commensals; now they are considered as parasitic organisms. In people, Demodex spp. can be found mainly in the sebaceous glands of the skin (mainly in the area of the forehead, cheeks, nose, behind ears and neck), in hearing aids, and on the scalp, covered with hair. Infection with demodex happens through direct contact with infected bed linen, towels, creams and other cosmetics. Despite the high prevalence of Demodex spp. in the human population, symptoms of demodecosis are not common, and can be found mainly in people with weakened immune systems due to aging or a number of diseases.

  7. Isolation of a virulent Lactobacillus brevis phage and its application in the control of beer spoilage.

    PubMed

    Deasy, Therese; Mahony, Jennifer; Neve, Horst; Heller, Knut J; van Sinderen, Douwe

    2011-12-01

    Beer quality can be compromised by the growth of certain lactobacilli, in particular Lactobacillus brevis and Lactobacillus plantarum, and various strategies have been used to control such bacterial spoilage. Biocontrol by means of bacteriophage is a reemerging approach for the suppression of spoilage bacteria in food and beverage matrices. A virulent phage capable of infecting L. brevis beer-spoilage strains was isolated and morphologically assessed by electron microscopy. The myophage SA-C12 was shown to be stable in beer and capable of controlling the growth of its host, L. brevis strain 56, in commercial beer. The results of this study indicate that bacteriophage-based treatments may be used as an alternative and natural strategy for the control of bacterial contamination of beer.

  8. Toxic effects of Karenia mikimotoi extracts on mammalian cells

    NASA Astrophysics Data System (ADS)

    Chen, Yang; Yan, Tian; Yu, Rencheng; Zhou, Mingjiang

    2011-07-01

    Karenia is one of the most harmful and representative red tide genus in a temperate zone. Blooms caused by this genus have resulted in massive fish death in the South China Sea and the East China Sea. However, the potential effects of this dinoflagellate on human health through the transfer of toxins via marine food webs, and the mechanisms of toxicity, are still unknown. Therefore, we examined the toxic effects of a strain of K. mikimotoi (isolated from the South China Sea) on the proliferation and morphology of four mammalian cell lines (two normal cell lines and two cancer cell lines). In addition, we carried out a preliminary investigation on the mechanism of toxicity of the alga. The results show that the polar lipid-soluble component of K. mikimotoi significantly inhibited proliferation of the four cell lines, and resulted in the cells becoming spherical, swollen and damaged. The result of Annexin V and PI double-staining confirmed that cell membranes were disrupted. The malonaldehyde (MDA) contents in the medium of the four cell lines treated with the polar-lipid extracts all increased significantly, which indicates that the polar-lipid toxins produced by K. mikimotoi could adversely affect mammalian cells by inducing lipid peroxidation. We conclude that K. mikimotoi is a potential threat to human health, and the comprehensive effect of this dinoflagellate and its mechanisms should be investigated further.

  9. Palmaris brevis spasm: an occupational syndrome.

    PubMed

    Liguori, R; Donadio, V; Di Stasi, V; Cianchi, C; Montagna, P

    2003-05-27

    Described are five patients who developed palmaris brevis (PB) spasm syndrome following prolonged use of a computer mouse and keyboard. Electromyography showed spontaneous activity characterized by irregular discharges of single motor unit potentials and myokymia from PB muscle that did not disappear after ulnar nerve block at the wrist, suggesting a distal lesion.

  10. Brevenal Is a Natural Inhibitor of Brevetoxin Action in Sodium Channel Receptor Binding Assays

    PubMed Central

    Bourdelais, Andrea J.; Campbell, Susan; Jacocks, Henry; Naar, Jerome; Wright, Jeffery L. C.; Carsi, Jigani; Baden, Daniel G.

    2009-01-01

    Summary 1. Florida red tides produce profound neurotoxicity that is evidenced by massive fish kills, neurotoxic shellfish poisoning, and respiratory distress. Red tides vary in potency, potency that is not totally governed by toxin concentration. The purpose of the study was to understand the variable potency of red tides by evaluating the potential for other natural pharmacological agents which could modulate or otherwise reduce the potency of these lethal environmental events. 2. A synaptosome binding preparation with 3-fold higher specific brevetoxin binding was developed to detect small changes in toxin binding in the presence of potential antagonists. Rodent brain labeled in vitro with tritiated brevetoxin shows high specific binding in the cerebellum as evidenced by autoradiography. Synaptosome binding assays employing cerebellum-derived synaptosomes illustrate 3-fold increased specific binding. 3. A new polyether natural product from Florida's red tide dinoflagellate Karenia brevis, has been isolated and characterized. Brevenal, as the nontoxic natural product is known, competes with tritiated brevetoxin for site 5 associated with the voltage-sensitive sodium channel (VSSC). Brevenal displacement of specific brevetoxin binding is purely competitive in nature. 4. Brevenal, obtained from either laboratory cultures or field collections during a red tide, protects fish from the neurotoxic effects of brevetoxin exposure. 5. Brevenal may serve as a model compound for the development of therapeutics to prevent or reverse intoxication in red tide exposures. PMID:15233378

  11. A 1-D Simulation Analysis of the Development and Maintenance of the 2001 Red Tide of the Ichthyotoxic Dinoflagellate Karenia brevis on the West Florida Shelf

    DTIC Science & Technology

    2012-04-26

    square of the correlation coefficient (r2). We utilized this set of quanti- tative metrics for univariate comparison of model results with observations as...standard deviation (RMSE/P), modeling efficiency (MEF) and correlation coefficient (r2). The coefficient of determination measures the tendency of the...modulate seasonal phytoplankton succession after the initial diatom spring bloom, once summer deposition events of iron- laden Saharan dust allow

  12. Solvent tolerance acquired by Brevibacillus brevis during an olive-waste vermicomposting process.

    PubMed

    Moreno, Beatriz; Vivas, Astrid; Nogales, Rogelio; Benitez, Emilio

    2009-11-01

    In this work, a cultivable, Gram-positive, solvent-resistant bacterium was isolated from vermicomposted olive wastes (VOW). The highest 16S rRNA sequence similarity (99%) was found in Brevibacillus brevis. The genome of the isolate, selected for trichloroethylene (TCE)-tolerance, contained a nucleotide sequence encoding a conserved protein domain (ACR_tran) ascribable to the HAE1-RND family. Members of this family are hydrophobic/amphiphilic efflux pumps largely restricted to Gram-negative bacteria. No DNA sequences of HAE1 transporters were detected in the genome of a reference B. brevis strain isolated from natural soil. Since no cultivable solvent-tolerant bacterium was detected in the unvermicomposted olive waste, a transfer of solvent-resistance genes from Gram-negative bacteria during the vermicomposting process could explain the presence of HAE1 transporters in B. brevis isolated from the vermicompost. Under TCE stress conditions, the acquired nucleotide sequence could be translated into proteins, and the tolerance to solvents is conferred to the bacterium. The isolate was designated as strain BEA1 (EF079071).

  13. Lactobacillus brevis strains from fermented aloe vera survive gastroduodenal environment and suppress common food borne enteropathogens.

    PubMed

    Kim, Young-Wook; Jeong, Young-Ju; Kim, Ah-Young; Son, Hyun-Hee; Lee, Jong-Am; Jung, Cheong-Hwan; Kim, Chae-Hyun; Kim, Jaeman

    2014-01-01

    Five novel Lactobacillus brevis strains were isolated from naturally fermented Aloe vera leaf flesh. Each strain was identified by Random Amplified Polymorphic DNA (RAPD) analysis and 16S rRNA sequence comparison. These strains were highly tolerant to acid, surviving in pH2.5 for up to 4 hours, and resistant to 5% bile salts at 37°C for 18 hours. Due to its tolerance to acid and bile salts, one strain passed through the gastric barrier and colonised the intestine after oral administration. All five strains inhibited the growth of many harmful enteropathogens without restraining most of normal commensals in the gut and hence named POAL (Probiotics Originating from Aloe Leaf) strains. Additionally, each strain exhibited discriminative resistance to a wide range of antibiotics. The L. brevis POAL strains, moreover, expressed high levels of the glutamate decarboxylase (GAD) gene which produces a beneficial neurotransmitter, γ-aminobutyric acid (GABA). These characteristics in all suggest that the novel L. brevis strains should be considered as potential food additives and resources for pharmaceutical research.

  14. Lactobacillus brevis Strains from Fermented Aloe vera Survive Gastroduodenal Environment and Suppress Common Food Borne Enteropathogens

    PubMed Central

    Kim, Young-Wook; Jeong, Young-Ju; Kim, Ah-Young; Son, Hyun-Hee; Lee, Jong-Am; Jung, Cheong-Hwan; Kim, Chae-Hyun; Kim, Jaeman

    2014-01-01

    Five novel Lactobacillus brevis strains were isolated from naturally fermented Aloe vera leaf flesh. Each strain was identified by Random Amplified Polymorphic DNA (RAPD) analysis and 16S rRNA sequence comparison. These strains were highly tolerant to acid, surviving in pH2.5 for up to 4 hours, and resistant to 5% bile salts at 37°C for 18 hours. Due to its tolerance to acid and bile salts, one strain passed through the gastric barrier and colonised the intestine after oral administration. All five strains inhibited the growth of many harmful enteropathogens without restraining most of normal commensals in the gut and hence named POAL (Probiotics Originating from Aloe Leaf) strains. Additionally, each strain exhibited discriminative resistance to a wide range of antibiotics. The L. brevis POAL strains, moreover, expressed high levels of the glutamate decarboxylase (GAD) gene which produces a beneficial neurotransmitter, γ-aminobutyric acid (GABA). These characteristics in all suggest that the novel L. brevis strains should be considered as potential food additives and resources for pharmaceutical research. PMID:24598940

  15. Novel bioactive from Lactobacillus brevis DSM17250 to stimulate the growth of Staphylococcus epidermidis: a pilot study.

    PubMed

    Holz, C; Benning, J; Schaudt, M; Heilmann, A; Schultchen, J; Goelling, D; Lang, C

    2017-02-07

    Commensal skin microbiota plays an important role in both influencing the immune response of the skin and acting as a barrier against colonisation of potentially pathogenic microorganisms and overgrowth of opportunistic pathogens. Staphylococcus epidermidis is a key constituent of the normal microbiota on human skin. It balances the inflammatory response after skin injury and produces antimicrobial molecules that selectively inhibit skin pathogens. Here we describe Lactobacillus brevis DSM17250 that was identified among hundreds of Lactobacillus strains to exhibit an anti-inflammatory effect in human keratinocytes in vitro and specific stimulatory impact on the growth of S. epidermidis. The aqueous cell-free extract of L. brevis DSM17250 was used in an ointment formulation and tested in a randomized placebo-controlled double blinded human pilot study. Healthy volunteers with diagnosed dry skin were treated for four weeks. The study data shows that L. brevis DSM17250 extract induces re-colonisation of the skin by protective commensal microorganisms as judged from selective bacterial cultivation of surface-associated skin microorganism of the lower leg. Furthermore, the 4 week administration of the L. brevis DSM17250 extract significantly improved the transepidermal water loss value (TEWL), reduced the xerosis cutis symptoms and stinging. The data shows that daily application of L. brevis DSM17250 extract in a topical product significantly improves the microbial skin microbiota by promoting the growth of species which possess beneficial regulatory and protective properties such as S. epidermidis. Restoring the natural skin microbiota leads to significantly improved skin barrier function (as transepidermal water loss) and decrease of xeroderma (xerosis cutis) symptoms (as measured by dry skin area and severity index, DASI). We propose that improving and stabilizing the natural skin microbiota by specifically stimulating the growth of S. epidermidis is an important and

  16. Tyrosine decarboxylase activity of Lactobacillus brevis IOEB 9809 isolated from wine and L. brevis ATCC 367.

    PubMed

    Moreno-Arribas, V; Lonvaud-Funel, A

    1999-11-01

    Tyramine, a frequent amine in wines, is produced from tyrosine by the tyrosine decarboxylase (TDC) activity of bacteria. The tyramine-producing strain Lactobacillus brevis IOEB 9809 isolated from wine and the reference strain L. brevis ATCC 367 were studied. At the optimum pH, 5.0, K(m) values of IOEB 9809 and ATCC 367 crude extracts for L-tyrosine were 0.58 mM and 0.67 mM, and V(max) was higher for the wine strain (115 U) than the ATCC 367 (66 U). TDC exhibited a preference for L-tyrosine over L-DOPA as substrate. Enzyme activity was pyridoxal-5'-phosphate (PLP)-dependent and it was stabilized by the substrate and coenzyme. In contrast, glycerol and beta-mercaptoethanol strongly inhibited TDC. Tyramine competitively inhibited TDC for both strains. Citric acid, lactic acid and ethanol had an inhibitory effect on cells and crude extracts, but none could inhibit TDC at the usual concentrations in wines.

  17. EMG biofeedback of the abductor pollicis brevis in piano performance.

    PubMed

    Montes, R; Bedmar, M; Sol Martin, M

    1993-06-01

    The aim of the present study was to apply EMG biofeedback as an auxiliary to piano teaching techniques. We studied the changes in integrated electromyographic activity, using the abductor pollicis brevis functioning as an agonist during the teaching of identical selective movements of piano playing in two groups, one with EMG biofeedback and the other following traditional method of instruction. The analysis of variance revealed an increase in the peak amplitude and the relaxation rate values for the biofeedback group. These results have implications for the application of piano playing techniques and reveal EMG biofeedback as an aid in the teaching of thumb attack with the abductor pollicis brevis as agonist.

  18. Identification of Lactobacillus brevis using a species-specific AFLP-derived marker.

    PubMed

    Fusco, Vincenzina; Quero, Grazia Marina; Chieffi, Daniele; Franz, Charles M A P

    2016-09-02

    A simple and specific method for the rapid detection and identification of Lactobacillus brevis was developed. A fAFLP (Fluorescent Amplified Fragment Length Polymorphisms) marker for L. brevis was used to design oligonucleotide primers for a species-specific PCR assay, targeting a 125bp fragment of the gene encoding the aldo/keto reductase of the diketogulonate-reductase family of L. brevis. This assay resulted in 100% inclusivity and exclusivity of assignment of strains to the species L. brevis. The analytical specificity of this assay was successfully tested to identify L. brevis isolates from sourdoughs.

  19. High γ-aminobutyric acid production from lactic acid bacteria: emphasis on Lactobacillus brevis as a functional dairy starter.

    PubMed

    Wu, Qinglong; Shah, Nagendra P

    2016-03-15

    γ-Aminobutyric acid (GABA) and GABA-rich foods have shown anti-hypertensive and anti-depressant activities as the major functions in humans and animals. Hence, high GABA-producing lactic acid bacteria (LAB) could be used as functional starters for manufacturing novel fermented dairy foods. Glutamic acid decarboxylases (GADs) from LAB are highly conserved at the species level based on the phylogenetic tree of GADs from LAB. Moreover, two functionally distinct GADs and one intact gad operon were observed in all the completely sequenced Lactobacillus brevis strains suggesting its common capability to synthesize GABA. Difficulties and strategies for the manufacture of GABA-rich fermented dairy foods have been discussed and proposed, respectively. In addition, a genetic survey on the sequenced LAB strains demonstrated the absence of cell envelope proteinases in the majority of LAB including Lb. brevis, which diminishes their cell viabilities in milk environments due to their non-proteolytic nature. Thus, several strategies have been proposed to overcome the non-proteolytic nature of Lb. brevis in order to produce GABA-rich dairy foods.

  20. Glutamate decarboxylase from Lactobacillus brevis: activation by ammonium sulfate.

    PubMed

    Hiraga, Kazumi; Ueno, Yoshie; Oda, Kohei

    2008-05-01

    In this study, the glutamate decarboxylase (GAD) gene from Lactobacillus brevis IFO12005 (Biosci. Biotechnol. Biochem., 61, 1168-1171 (1997)), was cloned and expressed. The deduced amino acid sequence showed 99.6% and 53.1% identity with GAD of L. brevis ATCC367 and L. lactis respectively. The His-tagged recombinant GAD showed an optimum pH of 4.5-5.0, and 54 kDa on SDS-PAGE. The GAD activity and stability was significantly dependent on the ammonium sulfate concentration, as observed in authentic GAD. Gel filtration showed that the inactive form of the GAD was a dimer. In contrast, the ammonium sulfate-activated form was a tetramer. CD spectral analyses at pH 5.5 revealed that the structures of the tetramer and the dimer were similar. Treatment of the GAD with high concentrations of ammonium sulfate and subsequent dilution with sodium glutamate was essential for tetramer formation and its activation. Thus the biochemical properties of the GAD from L. brevis IFO12005 were significantly different from those from other sources.

  1. Triphenyltin biodegradation and intracellular material release by Brevibacillus brevis.

    PubMed

    Ye, Jinshao; Zhao, Hangjian; Yin, Hua; Peng, Hui; Tang, Litao; Gao, Jiong; Ma, Yujia

    2014-06-01

    Triphenyltin (TPT) is an endocrine disruptor that has polluted the global environment, and thus far, information regarding the mechanisms of TPT biodegradation and intracellular material release is limited. Here, TPT biodegradation was conducted by using Brevibacillus brevis. Degradation affecting factors, metabolite formation, ion and protein release, membrane permeability, and cell viability after degradation were investigated to reveal the biodegradation mechanisms. The results showed that TPT could be degraded simultaneously to diphenyltin and monophenyltin, with diphenyltin further degraded to monophenyltin, and ultimately to inorganic tin. During degradation process, B. brevis metabolically released Cl(-) and Na(+), and passively diffused Ca(2+). Protein release and membrane permeability were also enhanced by TPT exposure. pH ranging from 6.0 to 7.5 and relatively high biomass dosage in mineral salt medium improved TPT degradation. Biodegradation efficiency of 0.5 mg L(-1) TPT by 0.3 g L(-1)B. brevis at 25 °C for 5d was up to 80%.

  2. Interspecific competition and allelopathic interaction between Karenia mikimotoi and Dunaliella salina in laboratory culture

    NASA Astrophysics Data System (ADS)

    He, Dong; Liu, Jiao; Hao, Qiang; Ran, Lihua; Zhou, Bin; Tang, Xuexi

    2016-03-01

    Algal allelopathy is a manifold ecological/physiological phenomenon that is focused on chemical interactions and autotoxicity. We investigated the allelopathic interactions between Karenia mikimotoi and Dunaliella salina in laboratory cultures based on diff erent temperature (15°C, 20°C, and 25°C) and lighting (40, 80, and 160 μmol/(m2·s)) conditions. The growth of D. salina in bi-algae culture (1:1 size/density) was significantly restrained. The results of cell-free filtrate culture indicate that direct cell-tocell contact was not necessary in interspecific competition. Further experimental results demonstrated that allelochemicals released from K. mikimotoi were markedly influenced by both temperature ( P =0.013) and irradiance ( P =0.003), resulting in diff erent growth characteristics of D. salina in filtrate mediums. Compared with the plateau period, K. mikimotoi exudates in the exponential phase had a stronger short-term inhibition effect on D. salina in normal conditions. A clear concentration-dependent relationship was observed in the effect of allelochemicals released from K. mikimotoi with low-promoting and high-repressing effects on D. Salina in a short time-scale. In addition, allelopathic substances remain stable and effective under high temperature and pressure stress. Many flocculent sediments adhering with D. salina cells were observed in all filtrate mediums, while the quantity and color depended on the original culture conditions.

  3. Allelopathic interactions between Prorocentrum micans and Skeletonema costatum or Karenia mikimotoi in laboratory cultures

    NASA Astrophysics Data System (ADS)

    Ji, Xiaoqing; Han, Xiaotian; Zheng, Li; Yang, Baijuan; Yu, Zhiming; Zou, Jingzhong

    2011-07-01

    Algal allelopathy is an ecological/physiological phenomenon that has focused attention on the interactions among algae and the production of algal toxins. We investigated the allelopathic interactions between the dinoflagellate genus Prorocentrum micans and diatom genus Skeletonema costatum and between P. micans and dinoflagellate genus Karenia mikimotoi using bi-algal cultures. Because the effects were species-specific and size-dependent, we evaluated the effect of different initial densities. At low densities of P. micans and high densities of S. costatum inoculated into the same medium, the growth of P. micans was weakly restrained, whereas the growth of S. costatum was significantly suppressed. S. costatum and K. mikimotoi were strongly inhibited by P. micans, in both the bi-algal cultures and enriched filtrates. Direct cell-to-cell contact was not necessary to gain a competitive advantage, thus, our results suggest that P. micans inhibited the growth of S. costatum and K. mikimotoi by the release of allelochemical(s). Last, a mathematical model was used to simulate growth and interactions between P. micans and S. costatum and between P. micans and K. mikimotoi in bi-algal cultures.

  4. Chemical Response of the Toxic Dinoflagellate Karenia mikimotoi Against Grazing by Three Species of Zooplankton.

    PubMed

    Dang, Lin-Xi; Li, Yue; Liu, Fei; Zhang, Yong; Yang, Wei-Dong; Li, Hong-Ye; Liu, Jie-Sheng

    2015-01-01

    We investigated the toxicity of Karenia mikimotoi toward three model grazers, the cladoceran Moina mongolica, the copepod Pseudodiaptomus annandalei, and the crustacean Artemia salina, and explored its chemical response upon zooplankton grazing. An induction experiment, where K. mikimotoi was exposed to grazers or waterborne cues from the mixed cultures revealed that K. mikimotoi might be toxic or nutritionally inadequate toward the three grazers. In general, direct exposure to the three grazers induced the production of hemolytic toxins and the synthesis of eicosapentaenoic acid (EPA). Both EPA and the hemolytic toxins from K. mikimotoi decreased the survival rate of the three grazers. In addition, the survival rates of M. mongolica, P. annandalei, and A. salina in the presence of induced K. mikimotoi that had previously been exposed to a certain grazer were lower than their counterparts caused by fresh K. mikimotoi, suggesting that exposure to some grazers might increase the toxicity of K. mikimotoi. The chemical response and associated increased resistance to further grazing suggested that K. mikimotoi could produce deterrents to protect against grazing by zooplankton and that the substances responsible might be hemolytic toxins and EPA.

  5. Effects of temperature on growth, photophysiology, Rubisco gene expression in Prorocentrum donghaiense and Karenia mikimotoi

    NASA Astrophysics Data System (ADS)

    Shen, Anglu; Ma, Zengling; Jiang, Keji; Li, Daoji

    2016-12-01

    To explore the effects of temperature changes on dinoflagellate bloom succession in the coastal waters of the East China Sea, changes in the growth, photophysiology, and Rubisco gene expression of Prorocentrum donghaiense and Karenia mikimotoi, two harmful algal species, were investigated at different temperatures (16 to 28°C). The maximal specific growth rate and the maximal mRNA expression of Rubisco gene in P. donghaiense and K. mikimotoi occurred at 20 and 24°C, respectively. The photosynthetic activity of P. donghaiense was generally stable, but K. mikimotoi photosynthesis increased when temperatures rose from 16 to 28°C. The effective photochemical efficiency ( F q ' / F m ' ) and the maximal relative electron transfer rate (rETRmax) of K. mikimotoi increased significantly with increasing temperature, and the lowest and highest values occurred at 16 and 28°C, respectively. It seems that P. donghaiense has higher photosynthetic capacity than K. mikimotoi due to its higher F q ' / F m ' , rETRmax, and photosynthetic efficiency (α). However, K. mikimotoi has a higher growth rate than P. donghaiense. These results suggest that the photosynthetic activity and genetic responses of dinoflagellates are species-dependent. It is likely that temperature changes affect species composition during blooms, leading to the observed patterns of bloom succession.

  6. Purification and Characterization of Bacteriocin Produced by Lactobacillus brevis UN Isolated from Dhulliachar: a Traditional Food Product of North East India.

    PubMed

    Gautam, Neha; Sharma, Nivedita; Ahlawat, O P

    2014-06-01

    A bacteriocin producing strain Lactobacillus brevis UN isolated from Dulliachar-a salted pickle and identified by biochemical and molecular methods. L. brevis UN was found to produce bacteriocin with broad spectrum activity against spoilage causing/food borne pathogens viz. L. monocytogenes, C. perfringens, S. aureus, L. mesenteroides, L. plantarum and B. cereus. Bacteriocin production was optimized through classical one variable at a time method. The isolate showed maximum bacteriocin production at early stationary phase, pH 4.0, temperature 35 °C and with an inoculum size of 1.5 OD @ 10 %. Bacteriocin produced by L. brevis UN was purified to homogeneity by single step gel exclusion chromatography and was most active at pH 6.0 and 7.0, stable up to 100 °C and was proteinaceous in nature. The results of NMR revealed the presence of proline, glutamic acid, aspartic acid, leucine, isoleucine and serine in its peptide structure. PCR amplification analysis determined that bacteriocin encoded gene in L. brevis UN was plasmid bound.

  7. Dairy Streptococcus thermophilus improves cell viability of Lactobacillus brevis NPS-QW-145 and its γ-aminobutyric acid biosynthesis ability in milk.

    PubMed

    Wu, Qinglong; Law, Yee-Song; Shah, Nagendra P

    2015-08-06

    Most high γ-aminobutyric acid (GABA) producers are Lactobacillus brevis of plant origin, which may be not able to ferment milk well due to its poor proteolytic nature as evidenced by the absence of genes encoding extracellular proteinases in its genome. In the present study, two glutamic acid decarboxylase (GAD) genes, gadA and gadB, were found in high GABA-producing L. brevis NPS-QW-145. Co-culturing of this organism with conventional dairy starters was carried out to manufacture GABA-rich fermented milk. It was observed that all the selected strains of Streptococcus thermophilus, but not Lactobacillus delbrueckii subsp. bulgaricus, improved the viability of L. brevis NPS-QW-145 in milk. Only certain strains of S. thermophilus improved the gadA mRNA level in L. brevis NPS-QW-145, thus enhanced GABA biosynthesis by the latter. These results suggest that certain S. thermophilus strains are highly recommended to co-culture with high GABA producer for manufacturing GABA-rich fermented milk.

  8. Dairy Streptococcus thermophilus improves cell viability of Lactobacillus brevis NPS-QW-145 and its γ-aminobutyric acid biosynthesis ability in milk

    PubMed Central

    Wu, Qinglong; Law, Yee-Song; Shah, Nagendra P.

    2015-01-01

    Most high γ-aminobutyric acid (GABA) producers are Lactobacillus brevis of plant origin, which may be not able to ferment milk well due to its poor proteolytic nature as evidenced by the absence of genes encoding extracellular proteinases in its genome. In the present study, two glutamic acid decarboxylase (GAD) genes, gadA and gadB, were found in high GABA-producing L. brevis NPS-QW-145. Co-culturing of this organism with conventional dairy starters was carried out to manufacture GABA-rich fermented milk. It was observed that all the selected strains of Streptococcus thermophilus, but not Lactobacillus delbrueckii subsp. bulgaricus, improved the viability of L. brevis NPS-QW-145 in milk. Only certain strains of S. thermophilus improved the gadA mRNA level in L. brevis NPS-QW-145, thus enhanced GABA biosynthesis by the latter. These results suggest that certain S. thermophilus strains are highly recommended to co-culture with high GABA producer for manufacturing GABA-rich fermented milk. PMID:26245488

  9. A Bayesian network approach to determine environmental factors controlling Karenia selliformis occurrences and blooms in the Gulf of Gabès, Tunisia.

    PubMed

    Feki-Sahnoun, Wafa; Hamza, Asma; Njah, Hasna; Barraj, Nouha; Mahfoudi, Mabrouka; Rebai, Ahmed; Hassen, Malika Bel

    2017-03-01

    A Bayesian Network modeling framework is introduced to explore the effect of physical and meteorological factors on the dinoflagellate red tide forming Karenia selliformis in various sampling sites of the national phytoplankton monitoring program. The proposed models took into account the physical environment effects (salinity, temperature and tide amplitude), meteorological constraints (evaporation, air temperature, insolation, rainfall, atmospheric pressure and humidity), sampling months and sites on both Karenia selliformis occurrences and blooms. The models produced plausible results and enabled the identification of the factors that directly impacted on the species occurrences and concentration levels. The sampling sites dominated the species occurrences. The models show that the relationship between salinity and Karenia selliformis is more apparent when the species concentrations are focused on and that the bloom occurrences can be predicted based on salinity. Concentrations up to 10(5) cells L(-1) were recorded when salinity exceeded 42.5 and dominated the shallow and weak water renewal areas.

  10. Antifeedant Activity of Citrus Waste Wax and Its Fractions Against the Dry Wood Termite, Cryptotermes brevis

    PubMed Central

    Sbeghen-Loss, Ana Carolina; Mato, Mauricio; Cesio, Maria Veronica; Frizzo, Caren; de Barros, Neiva Monteiro; Heinzen, Horacio

    2011-01-01

    The wood protective action of citrus wax, a waste from the citrus industry that is a mixture of citrus fruit epicuticular waxes and essential oils, was evaluated against the termite Cryptotermes brevis Walker (Isoptera: Kalotermitidae). The antifeedant index (AI) of the total wax and fractions was calculated. The total citrus wax exhibited an AI50 value of 24.69 mg/cm3, the wax after hydrodistillation showed the strongest antifeedant property (AI50 11.68 mg/cm3). Fractionation of the wax and gas chromatography—mass spectrometric analysis allowed the identification of coumarins and furancoumarins as the active compounds. These results suggest the potential use of these industrial residues as a natural approach to termite control. PMID:22243487

  11. Brevisulcatic acids, marine ladder-frame polyethers from the red tide dinoflagellate Karenia brevisulcata in New Zealand.

    PubMed

    Suzuki, Rina; Irie, Raku; Harntaweesup, Yanit; Tachibana, Kazuo; Holland, Patrick T; Harwood, D Tim; Shi, Feng; Beuzenberg, Veronica; Itoh, Yoshiyuki; Pascal, Steven; Edwards, Patrick J B; Satake, Masayuki

    2014-11-21

    The isolation and structural determination of new marine ladder-frame polyethers, brevisulcatic acids-1 (1) and -4 (2) are reported. Brevisulcatic acids were isolated from the dinoflagellate Karenia brevisulcata, which was identified as the causative species of a major red tide event in New Zealand in 1998. The ether ring composition and a β-hydroxy, γ-methylene valeric acid side chain of 1 and 2 are common, but 2 has a γ-lactone as the 5-membered A-ring while 1 is the seco acid analogue. Compound 2 has structural and bioactivity similarities to brevetoxin A.

  12. [A method for reconstruction of the A1 retinaculum in the flexor pollicis longus sheath with extensor pollicis brevis tendon].

    PubMed

    Chmiel, Z

    1996-01-01

    An original method for A1 retinaculum reconstruction of flexor pollicis longus sheath with extensor pollicis brevis tendon is presented. Reconstructed retinaculum is very strong. Loss of extensor pollicis brevis did not impaired thumb function.

  13. Gramicidin S production by Bacillus brevis in simulated microgravity

    NASA Technical Reports Server (NTRS)

    Fang, A.; Pierson, D. L.; Mishra, S. K.; Koenig, D. W.; Demain, A. L.

    1997-01-01

    In a continuing study of microbial secondary metabolism in simulated microgravity, we have examined gramicidin S (GS) production by Bacillus brevis strain Nagano in NASA High Aspect Rotating Vessels (HARVs), which are designed to simulate some aspects of microgravity. Growth and GS production were found to occur under simulated microgravity. When performance under simulated microgravity was compared with that under normal gravity conditions in the bioreactors, GS production was found to be unaffected by simulated microgravity. The repressive effect of glycerol in flask fermentations was not observed in the HARV. Thus the negative effect of glycerol on specific GS formation is dependent on shear and/or vessel geometry, not gravity.

  14. Coexpression of pyruvate decarboxylase and alcohol dehydrogenase genes in Lactobacillus brevis.

    PubMed

    Liu, Siqing; Dien, Bruce S; Nichols, Nancy N; Bischoff, Kenneth M; Hughes, Stephen R; Cotta, Michael A

    2007-09-01

    Lactobacillus brevis ATCC367 was engineered to express pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) genes in order to increase ethanol fermentation from biomass-derived residues. First, a Gram-positive Sarcina ventriculi PDC gene (Svpdc) was introduced into L. brevis ATCC 367 to obtain L. brevis bbc03. The SvPDC was detected by immunoblot using an SvPDC oligo peptide antiserum, but no increased ethanol was detected in L. brevis bbc03. Then, an ADH gene from L. brevis (Bradh) was cloned behind the Svpdc gene that generated a pdc/adh-coupled ethanol cassette pBBC04. The pBBC04 restored anaerobic growth and conferred ethanol production of Escheirichia coli NZN111 (a fermentative defective strain incapable of growing anaerobically). Approximately 58 kDa (SvPDC) and 28 kDa (BrADH) recombinant proteins were observed in L. brevis bbc04. These results indicated that the Gram-positive ethanol production genes can be expressed in L. brevis using a Gram-positive promoter and pTRKH2 shuttle vector. This work provides evidence that expressing Gram-positive ethanol genes in pentose utilizing L. brevis will further aid manipulation of this microbe toward biomass to ethanol production.

  15. Tea saponin enhanced biodegradation of decabromodiphenyl ether by Brevibacillus brevis.

    PubMed

    Tang, Shaoyu; Bai, Jieqiong; Yin, Hua; Ye, Jinshao; Peng, Hui; Liu, Zehua; Dang, Zhi

    2014-11-01

    Decabromodiphenyl ether (BDE209) is a ubiquitous persistent pollutant and has contaminated the environment worldwide. To accelerate BDE209 elimination and reveal the mechanism concerned, the biosurfactant tea saponin enhanced degradation of BDE209 by Brevibacillus brevis was conducted. The results revealed that tea saponin could efficiently increase the solubility of BDE209 in mineral salts medium and improve its biodegradation. The degradation efficiency of 0.5 mg L(-1) BDE209 by 1 g L(-1) biomass with surfactant was up to 55% within 5d. Contact time was a significant factor for BDE209 biodegradation. BDE209 biodegradation was coupled with bioaccumulation, ion release and utilization, and debromination to lower brominated PBDE metabolites. During the biodegradation process, B. brevis metabolically released Na(+), NH4(+), NO2(-) and Cl(-), and utilized the nutrient ions Mg(2+), PO4(3-) and SO4(2-). GC-MS analysis revealed that the structure of BDE209 changed under the action of strain and nonabromodiphenyl ethers (BDE-208, -207 and -206), octabromodiphenyl ethers (BDE-203, -197 and -196) and heptabromodiphenyl ether (BDE-183) were generated by debromination.

  16. Tyrosine decarboxylase from Lactobacillus brevis: soluble expression and characterization.

    PubMed

    Zhang, Kai; Ni, Ye

    2014-02-01

    Tyrosine decarboxylase (TDC, EC 4.1.1.25) is an enzyme that catalyzes the decarboxylation of l-tyrosine to produce tyramine and CO2. In this study, a 1881-bp tdc gene from Lactobacillus brevis was cloned and heterologously expressed in Escherichia coli BL21 (DE3). Glucose was discovered to play an important role in the soluble expression of rLbTDC. After optimization, recombinant TDC (rLbTDC) was achieved in excellent solubility and a yield of 224mg rLbTDC/L broth. The C-terminal His-Tagged rLbTDC was one-step purified with 90% recovery. Based on SDS-PAGE and gel filtration analysis, rLbTDC is a dimer composed of two identical subunits of approximately 70kDa. Using l-tyrosine as substrate, the specific activity of rLbTDC was determined to be 133.5U/mg in the presence of 0.2mM pyridoxal-5'-phosphate at 40°C and pH 5.0. The Km and Vmax values of rLbTDC were 0.59mM and 147.1μmolmin(-1)mg(-1), respectively. In addition to l-tyrosine, rLbTDC also exhibited decarboxylase activity towards l-DOPA. This study has demonstrated, for the first time, the soluble expression of tdc gene from L. brevis in heterologous host.

  17. Biosorption and biodegradation of triphenyltin by Brevibacillus brevis.

    PubMed

    Ye, Jinshao; Yin, Hua; Peng, Hui; Bai, Jieqiong; Xie, Danping; Wang, Linlin

    2013-02-01

    Triphenyltin (TPT) is an endocrine disruptor highly toxic to non-target organisms, and has contaminated the environment worldwide. To accelerate TPT elimination, the study on the behavior and mechanism of TPT biosorption and biodegradation by Brevibacillus brevis was conducted. The results revealed that TPT and coexisted Cu2+, Cd2+, Pb2+ and Zn2+ in solution could be adsorbed effectively by B. brevis, and TPT was further transformed to diphenyltin, monophenyltin and tin intracellularly. The removal efficiency of 0.5 mg L(-1) TPT after degradation by 0.3 g L(-1) biomass for 5d was about 60%. Suitable kinds and levels of oxygen, nutrient, surfactant and metals obviously improved TPT biodegradation. When concentrations of H2O2, glucose, rhamnolipid, Cu2+ and Zn2+ varied from 1.5 to 6 mmol L(-1), 0.5 to 5 mg L(-1), 5 to 25 mg L(-1), 0.5 to 6 mg L(-1) and 0.5 to 1 mg L(-1), separately, TPT biodegradation efficiencies increased 15-25%.

  18. Detection, partial purification and characterization of bacteriocin produced by Lactobacillus brevis FPTLB3 isolated from freshwater fish: Bacteriocin from Lb. brevis FPTLB3.

    PubMed

    Banerjee, Shiba Prosad; Dora, Krushna Chandra; Chowdhury, Supratim

    2013-02-01

    Lactobacillus brevis FPTLB3 was isolated from freshwater fish, capable of producing bacteriocin that had broad spectrum of inhibition (3200 AU/ml) against Escherichia coli MTCC 1563, Enterococcus faecalis MTCC 2729, Lactobacillus casei MTCC 1423, Lactobacillus sakei ATCC 15521 and Staphylococcus aureus ATCC 25923. The antimicrobial activity of crude supernatant fluid was stable after heating at 121 °C for 60 min and declined thereafter. Stability of antimicrobial activity was observed at pH range of 2.0 to 8.0. Its active principle was proteinaceous in nature since the bacteriocin was inactivated by proteolytic enzymes, but not by other non-proteolytic enzymes. Mitomycin C and UV light did not affect the activity of the bacteriocin, while chloroform extraction completely destroyed their activity. Exposure to surfactant resulted in an increase in titre, except Nonidet P-40, which led to total loss of activity. No bacteriocin adsorption was detected at pH 1 to 2, whereas 100% bacteriocin adsorption was found at pH 6.5. Based on Tricine SDS-PAGE the estimated molecular mass of bacteriocin was 54 kDa. No plasmid was found to present in the isolate.

  19. Gross morphology and ultrastructure of salivary glands of the mute cicada Karenia caelatata Distant (Hemiptera: Cicadoidea).

    PubMed

    Zhong, Hai-ying; Wei, Cong; Zhang, Ya-lin

    2013-02-01

    Salivary glands of the cicada Karenia caelatata Distant were investigated using light microscopy and transmission electron microscopy. The salivary glands are paired structures and consist of principal glands and accessory glands. The principal gland is subdivided into anterior lobe and posterior lobe; the former contains about 34-39 long digitate lobules, while the latter contains approximately 30-33 long digitate lobules and 13-22 short digitate lobules. These short digitate lobules, about one fifth or sixth as long as the long digitate lobules, locate at the base of the long digitate lobules of posterior lobe. All of these digitate lobules vary in size, disposition, length and shape. The anterior lobe and the posterior lobe are connected by an anterior-posterior duct. Two efferent salivary ducts, which connect with the posterior lobe, fuse to form a common duct. The accessory gland is composed of three parts: a greatly tortuous and folded accessory salivary tube, a circlet of gular gland constituting of several acini of the same size, and a non-collapsible accessory salivary duct. The digitate lobules and gular glands possess secretory cells containing abundant secretory granules vary in size, shape, and electron density, as might indicate different materials are synthesized in different secretory regions. The anterior-posterior duct lines with a player of cuticular lining, and cells beneath the cuticular lining lack of basal infoldings, as suggests the duct serves just to transport secretions. The accessory salivary duct is lined with cuticular lining; cells of the duct have well developed basal infoldings associated with abundant mitochondria, as probably suggests the duct is a reabsorptive region of ions. The cells of the accessory salivary tube possess deep basal infoldings and well developed apical dense microvilli, indicating the cells of the tube are secretory in function. Concentric lamellar structures and a peculiar structure with abundant membrane

  20. The Extensor Pollicis Brevis: A Review of Its Anatomy and Variations

    PubMed Central

    Jabir, Shehab; Lyall, Harry; Iwuagwu, Fortune C.

    2013-01-01

    Introduction: The standard anatomical description of the extensor pollicis brevis tendon provided in textbooks of anatomy is at odds with that of published anatomical studies. It is crucial to the hand surgeon that he or she has a clear understanding of its anatomy, including its variations. The aim of this study was to provide a comprehensive review of the current literature on the anatomy and variants of the extensor pollicis brevis. It is hoped that this review will be indispensable to the hand surgeon in informing him or her about the anatomy and variants encountered when dealing with the extensor pollicis brevis. Methods: Inclusion and exclusion criteria were defined and a literature search was carried out on MEDLINE, PubMed, Embase, and Google Scholar from inception to March 2013 for studies on the topic of extensor pollicis brevis anatomy. The following key words were used: “extensor pollicis brevis,” “anatomy,” “anatomic variations,” “cadaveric study,” “clinical study,” “case report,” and “dissection”. Results: The search retrieved a total of 52 studies following removal of duplicates. Forty-five studies were excluded following screening of the title and abstract. Three studies were excluded as they did not meet the eligibility criteria, leaving 4 cadaveric studies for inclusion in the review. Conclusion: We recommend the use of ultrasound scanning to determine anatomy of the extensor pollicis brevis before reconstructive procedures involving the extensor pollicis brevis, as well as in traumatic injuries to the extensor pollicis brevis. There appears to be ethnicity-related variations in the anatomy of the extensor pollicis brevis, and further study into these variations may be indicated. PMID:23882301

  1. Modified Evans peroneus brevis lateral ankle stabilization for balancing varus ankle contracture during total ankle replacement.

    PubMed

    Roukis, Thomas S

    2013-01-01

    Lateral ankle instability is frequently encountered when performing total ankle replacement and remains a challenge. In the present techniques report, I have described a modification of the Evans peroneus brevis tendon lateral ankle stabilization harvested through limited incisions using simple topographic anatomic landmarks. The harvested peroneus brevis is then transferred either to the anterior distal tibia concomitantly with total ankle replacement or through the tibia when performed after total ankle replacement and secured with plate and screw fixation. This modified Evans peroneus brevis tendon is useful in providing lateral ankle stability during or after primary and revision total ankle replacement.

  2. Regulation of the glucose:H+ symporter by metabolite-activated ATP-dependent phosphorylation of HPr in Lactobacillus brevis.

    PubMed Central

    Ye, J J; Neal, J W; Cui, X; Reizer, J; Saier, M H

    1994-01-01

    Lactobacillus brevis takes up glucose and the nonmetabolizable glucose analog 2-deoxyglucose (2DG), as well as lactose and the nonmetabolizable lactose analoge thiomethyl beta-galactoside (TMG), via proton symport. Our earlier studies showed that TMG, previously accumulated in L. brevis cells via the lactose:H+ symporter, rapidly effluxes from L. brevis cells or vesicles upon addition of glucose and that glucose inhibits further accumulation of TMG. This regulation was shown to be mediated by a metabolite-activated protein kinase that phosphorylase serine 46 in the HPr protein. We have now analyzed the regulation of 2DG uptake and efflux and compared it with that of TMG. Uptake of 2DG was dependent on an energy source, effectively provided by intravesicular ATP or by extravesicular arginine which provides ATP via an ATP-generating system involving the arginine deiminase pathway. 2DG uptake into these vesicles was not inhibited, and preaccumulated 2DG did not efflux from them upon electroporation of fructose 1,6-diphosphate or gluconate 6-phosphate into the vesicles. Intravesicular but not extravesicular wild-type or H15A mutant HPr of Bacillus subtilis promoted inhibition (53 and 46%, respectively) of the permease in the presence of these metabolites. Counterflow experiments indicated that inhibition of 2DG uptake is due to the partial uncoupling of proton symport from sugar transport. Intravesicular S46A mutant HPr could not promote regulation of glucose permease activity when electroporated into the vesicles with or without the phosphorylated metabolites, but the S46D mutant protein promoted regulation, even in the absence of a metabolite. The Vmax but not the Km values for both TMG and 2DG uptake were affected. Uptake of the natural, metabolizable substrates of the lactose, glucose, mannose, and ribose permeases was inhibited by wild-type HPr in the presence of fructose 1,6-diphosphate or by S46D mutant HPr. These results establish that HPr serine

  3. Heterologously expressed family 51 alpha-L-arabinofuranosidases from Oenococcus oeni and Lactobacillus brevis.

    PubMed

    Michlmayr, Herbert; Schümann, Christina; Kulbe, Klaus D; del Hierro, Andrés M

    2011-02-01

    Putative α-L-arabinofuranosidases of Oenococcus oeni and Lactobacillus brevis were heterologously expressed and characterized. We report the basic functional properties of the recombinant enzymes in comparison to those of a commercial family 51 arabinosidase of Aspergillus niger.

  4. In vivo expression of the Lactobacillus brevis S-layer gene.

    PubMed Central

    Kahala, M; Savijoki, K; Palva, A

    1997-01-01

    Lactobacillus brevis possesses a surface layer protein (SlpA) with tightly regulated synthesis. The slpA gene is expressed by two adjacent promoters, P1 and P2. The level of P2-derived transcripts was approximately 10 times higher than that of P1-derived transcripts throughout the entire growth of L. brevis. The half-lives of slpA transcripts were shown to be exceptionally long (14 min). PMID:8982011

  5. System identification of evoked mechanomyogram from abductor pollicis brevis muscle in isometric contraction.

    PubMed

    Uchiyama, Takanori; Sakai, Hiroaki

    2013-12-01

    The purpose of this study is to verify the applicability of a sixth-order model to the mechanomyogram (MMG) system of the parallel-fibered muscle, which was identified from the MMG of the pennation muscle. The median nerve was stimulated, and an MMG and torque of the abductor pollicis brevis muscle were measured. The MMGs were detected with either a capacitor microphone or an acceleration sensor. The transfer functions between stimulation and the MMG and between stimulation and torque were identified by the singular value decomposition method. The torque and the MMG, which were detected with a capacitor microphone, DMMG, were approximated with a second- and a third-order model, respectively. The natural frequency of the torque, reflecting longitudinal mechanical characteristics, did not show a significant difference from that of the DMMG. The MMG detected with an acceleration sensor was approximated with a fourth-order model. The natural frequencies of the AMMG reflecting the muscle and subcutaneous tissue in the transverse direction were obtained. Both DMMG and AMMG have to be measured to investigate the model of the MMG system for parallel-fibered muscle. The MMG system of parallel-fibered muscle was also modeled with a sixth-order model.

  6. Characterization of lactose utilization and β-galactosidase in Lactobacillus brevis KB290, the hetero-fermentative lactic acid bacterium.

    PubMed

    Honda, Hiroyuki; Yajima, Nobuhiro; Saito, Tadao

    2012-12-01

    Unlike dairy lactic acid bacteria, Lactobacillus brevis cannot ferment milk. We characterized the lactose utilization by L. brevis KB290. In a carbohydrate fermentation assay using API 50 CHL, we showed during 7 days L. brevis did not ferment lactose. L. brevis grew to the stationary phase in 2 weeks in MRS broth containing lactose as the carbon source. L. brevis slowly consumed the lactose in the medium. L. brevis hydrolyzed lactose and a lactose analog, o-nitrophenyl-β-D-galactopyranoside (ONPGal). This β-galactosidase activity for ONPGal was not repressed by glucose, galactose, fructose, xylose, or maltose showing the microorganism may not have carbon catabolite repression. We purified the L. brevis β-galactosidase using ammonium sulfate precipitation and several chromatographies. The enzyme's molecular weight is estimated at 72 and 37 kDa using SDS-PAGE analysis. The N-terminal amino acid sequence of the larger protein was 90 % similar to the sequence of the putative β-galactosidase (YP_796339) and the smaller protein was identical to the sequence of the putative β-galactosidase (YP_796338) in L. brevis ATCC367. This suggests the enzyme is a heterodimeric β-galactosidase. The specific activity of the purified enzyme for lactose is 55 U/mg. We speculate inhibition of lactose transport delays the lactose utilization in L. brevis KB290.

  7. Topical treatment with probiotic Lactobacillus brevis CD2 inhibits experimental periodontal inflammation and bone loss

    PubMed Central

    Maekawa, Tomoki; Hajishengallis, George

    2014-01-01

    Background and Objective An increasing body of evidence suggests that the use of probiotic bacteria is a promising intervention approach for the treatment of inflammatory diseases with polymicrobial etiology. The objective of this study was to determine whether Lactobacillus brevis CD2 could inhibit periodontal inflammation and bone loss in experimental periodontitis. Materials and Methods Periodontitis was induced by placing a silk ligature around the second maxillary molar of mice treated with L. brevis CD2 (8×105 CFU in 1-mm2 lyopatch) or placebo, which were placed between the gingiva and the buccal mucosa in the vicinity of the ligated teeth. The mice were euthanized after 5 days and bone loss was measured morphometrically, gingival expression of proinflammatory cytokines was determined by quantitative real-time PCR, and CFU counts of periodontitis-associated bacteria were determined after aerobic and anaerobic culture. To determine the role of arginine deiminase released by L. brevis CD2, soluble extracts with or without formamidine (arginine deiminase inhibitor) were tested in in vitro cellular activation assays. Results Mice topically treated with L. brevis CD2 displayed significantly decreased bone loss and lower expression of TNF, IL-1β, IL-6, and IL-17A as compared to placebo-treated mice. Moreover, L. brevis CD2-treated mice displayed lower counts of anaerobic bacteria but higher counts of aerobic bacteria than placebo-treated mice. In in vitro assays, the anti-inflammatory effects of soluble L. brevis CD2 extracts were heavily dependent on the presence of functional arginine deiminase, an enzyme that can inhibit nitric oxide synthesis. Conclusion These data provide proof-of-concept that the probiotic L. brevis CD2 can inhibit periodontitis through modulatory effects on the host response and the periodontal microbiota. PMID:24483135

  8. Characteristics of surface layer proteins from two new and native strains of Lactobacillus brevis.

    PubMed

    Mobarak Qamsari, Elahe; Kasra Kermanshahi, Rouha; Erfan, Mohammad; Ghadam, Parinaz; Sardari, Soroush; Eslami, Neda

    2017-02-01

    In this work, some important characteristics of surface layer (S-layer) proteins extracted from two new and native Lactobacillus strains, L.brevis KM3 and L.brevis KM7, were investigated. The presence of S-layer on the external surface of L.brevis KM3 was displayed by thin sectioning and negative staining. SDS-PAGE analysis were shown same dominant protein bands approximately around 48kDa for both S-layer proteins. Moreover, the S-layer reappeared when LiCl treated cells were allowed to grow again. Protein secondary structure and thermal behavior were evaluated by using circular dichroism (CD) and differential scanning calorimetry (DSC), respectively. Both S-layer proteins had high content of β-sheet and low amount of α-helix. The thermograms of lyophilized S-layer proteins of L.brevis KM3 and L.brevis KM7 showed one transition peak at 67.9°C and 59.14°C, respectively. To determine monodispersity of extracted S-layer proteins, dynamic light scattering (DLS) was used. The results indicated that the main population of S-layer molecules in two tested lactobacillus strains were composed of monomer with an expected diameter close to 10nm. Furthermore, Zeta potential measurements were showed positive potential for both S-layer proteins, as expected. Our results could be used as the basis for biotechnological applications of these two new S-layer proteins.

  9. Extracellular production of an intact and biologically active human growth hormone by the Bacillus brevis system.

    PubMed

    Kajino, T; Saito, Y; Asami, O; Yamada, Y; Hirai, M; Udata, S

    1997-10-01

    The characteristic features of the Bacillus brevis system are very high productivity of heterologous proteins and very low extracellular protease activity. However, degradation of some heterologous proteins, especially mammalian proteins, can be observed and resulted in a lowering of protein productivity. By using a mutant expressing low levels of proteases and the addition of EDTA to the medium, intact human growth hormone (hGH) was successfully produced with the B. brevis system. Signal peptide modification with higher basicity in the amino terminal region and higher hydrophobicity in the middle region brought about a twelve-fold increase in hGH production. The hGH yield was further elevated to 240 mg L-1 by optimization of culture conditions. Thus, biologically active and mature hGH can be efficiently produced directly in the medium with the B. brevis system.

  10. Reverse Evans peroneus brevis medial ankle stabilization for balancing valgus ankle contracture during total ankle replacement.

    PubMed

    Roukis, Thomas S; Prissel, Mark A

    2014-01-01

    Medial ankle instability secondary to deltoid ligament insufficiency is frequently encountered when performing total ankle replacement and remains a challenge. In the present techniques report, we describe a "reverse" Evans peroneus brevis tendon nonanatomic deltoid ligament reconstruction for medial ankle stabilization harvested through limited incisions using simple topographic anatomic landmarks. The harvested peroneus brevis tendon is brought through a drill hole in the talus from laterally to medially, aiming for the junction of the talar neck and body plantar to the midline. The tendon is the brought superiorly and obliquely to the anterior medial aspect of the distal tibia where it is secured under a plate and screw construct. This modified Evans peroneus brevis tendon nonanatomic deltoid ligament reconstruction is useful in providing medial ankle stability during or after primary and revision total ankle replacement.

  11. Effect of Lactobacillus brevis ATCC 8287 as a feeding supplement on the performance and immune function of piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lactobacillus brevis ATCC 8287, a surface (S-layer) strain, possesses a variety of functional properties that make it both a potential probiotic and a good vaccine vector candidate. With this in mind, our aim was to study the survival of L. brevis in the porcine gut and investigate the effect of th...

  12. Effect of various nitrogen conditions on population growth, temporary cysts and cellular biochemical compositions of Karenia mikimotoi

    PubMed Central

    Zhao, Yan; Tang, Xuexi; Zhao, Xiaowei; Wang, You

    2017-01-01

    The harmful algal bloom (HAB)-forming dinoflagellate Karenia mikimotoi was exposed to different nitrogen (N) conditions, in order to study the population growth, temporary cyst production and cellular biochemical compositions in laboratory. The results indicated the population growth of K. mikimotoi was inhibited by different levels of N starvation but showed similar fast recovery after the resupplement of N, and temporary cysts were induced in the period of N starvation. K. mikimotoi grew well in inorganic (NO3-, NO2- and NH4+) and organic (urea) nitrogen sources, but the growth parameters (K, Tp, r) showed differences when simulated by Logistic model regressions. When the cellular organic compounds were measured simultaneously, K. mikimotoi cultured in urea produced more short-chained fatty acids while K. mikimotoi cultured in NH4+ produced more non-fatty acids compounds, indicating the potential change of toxins production cultured by various N sources. We concluded that K. mikimotoi could adapt to fluctuating N environments typical of coastal environments including total N concentration (deficiency or recovery) and relative compositions (different N sources). PMID:28225802

  13. The diet of Enoplus brevis (Nematoda) in a supralittoral salt marsh of the North Sea

    NASA Astrophysics Data System (ADS)

    Hellwig-Armonies, Monika; Armonies, Werner; Lorenzen, Sievert

    1991-09-01

    The gut content of nearly 2000 specimens of Enoplus brevis was quantitatively analysed. E. brevis is an opportunistic omnivore. Main food categories found were cyanobacteria, diatoms, oligochaetes, nematodes, and rotifers. With a few exceptions, the diet of females and males was identical. Predominantly, juveniles fed on cyanobacteria and adults on animal prey. Experiments revealed that living oligochaetes are attacked and preyed upon. The quantities of the food categories eaten by Enoplus varied according to their ambient abundance, both temporarily and spatially on a small scale. At least the nematode prey was strongly selected: some species were significantly preferred and others avoided.

  14. Effect of orally administered Lactobacillus brevis HY7401 in a food allergy mouse model.

    PubMed

    Lee, Jeongmin; Bang, Jieun; Woo, Hee-Jong

    2013-11-28

    We had found that orally administered Lactobacillus species were effective immune modulators in ovalbumin (OVA)-sensitized mice. To validate these findings, we investigated the effects of orally administered Lactobacillus brevis HY7401 in OVA-T cell receptor transgenic mice. This strain showed a tendency to induce Th1 cytokines and inhibit Th2 cytokines. All assayed isotypes of OVA-specific antibody were effectively reduced. Systemic anaphylaxis was also relatively reduced with the probiotic administration. These results reveal that L. brevis HY7401 might be useful to promote anti-allergic processes through oral administration.

  15. S-layer protein gene of Lactobacillus brevis: cloning by polymerase chain reaction and determination of the nucleotide sequence.

    PubMed Central

    Vidgrén, G; Palva, I; Pakkanen, R; Lounatmaa, K; Palva, A

    1992-01-01

    The surface (S)-layer protein of Lactobacillus brevis was isolated, purified, and characterized. The S-layer protein is the major protein of the cell, with an apparent molecular mass of 46 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Immunogold electron microscopy with polyclonal antiserum against the isolated 46-kDa protein was used to confirm the surface location of this protein. N-terminal amino acid sequences of the intact 46-kDa protein and its tryptic peptides were determined. The gene of the S-layer protein was amplified from the genome of L. brevis by polymerase chain reaction with oligonucleotides, synthesized according to the N-terminal amino acid sequences, as primers. The polymerase chain reaction fragments containing the entire S-layer gene and its regulatory regions were sequenced. Nucleic acid sequence analysis revealed one open reading frame with a capacity to encode a protein of 48,159 Da. From the regulatory region of the gene, two subsequent promoters and a ribosome binding site, showing typical features of prokaryotic consensus sequences, were found. The coding region contained a characteristic gram-positive-type signal peptide of 30 amino acids. Removal of the signal peptide results in a polypeptide of 435 amino acids, which is in excellent agreement with the size of the S-layer protein determined by SDS-PAGE. The size and the 5' end analyses of the S-layer transcripts confirmed the monocistronic nature of the S-layer operon and the functionality of the two promoters found. Images PMID:1429463

  16. Mycelial carton galleries of Azteca brevis (Formicidae) as a multi-species network.

    PubMed

    Mayer, Veronika E; Voglmayr, Hermann

    2009-09-22

    Apart from growing fungi for nutrition, as seen in the New World Attini, ants cultivate fungi for reinforcement of the walls of their nests or tunnel-shaped runway galleries. These fungi are grown on organic material such as bark, epiphylls or trichomes, and form stable 'carton structures'. In this study, the carton of the runway galleries built by Azteca brevis (Formicidae, Dolichoderinae) on branches of Tetrathylacium macrophyllum (Flacourtiaceae) is investigated. For the first time, molecular tools are used to address the biodiversity and phylogenetic affinities of fungi involved in tropical ant carton architecture, a previously neglected ant-fungus mutualism. The A. brevis carton involves a complex association of several fungi. All the isolated fungi were unequivocally placed within the Chaetothyriales by DNA sequence data. Whereas five types of fungal hyphae were morphologically distinguishable, our DNA data showed that more species are involved, applying a phylogenetic species concept based on DNA phylogenies and hyphal morphology. In contrast to the New World Attini with their many-to-one (different ant species-one fungal cultivar) pattern, and temperate Lasius with a one-to-two (one ant species-two mutualists) or many-to-one (different ant species share the same mutualist) system, the A. brevis-fungi association is a one-to-many multi-species network. Vertical fungus transmission has not yet been found, indicating that the A. brevis-fungi interaction is rather generalized.

  17. Purification and partial characterization of an antigen specific to Lactobacillus brevis strains with beer spoilage activity.

    PubMed

    Yasui, T; Yoda, K

    1997-06-15

    Certain Lactobacillus brevis strains are resistant to hop-derived compounds such as isohumulone and are able to grow in beer. In this study, we raised an antiserum against our beer spoilage laboratory strain L. brevis 578 which reacted with 23 of 24 beer spoilers and two of 13 non-spoilers in precipitation reactions using 0.5 M NaOH cell extracts. This specific antigen to the beer spoilage L. brevis strains (SABSL) was demonstrated to be located beneath the S-layer proteins by agglutination reactions using S-layer protein-stripped cells obtained by treatment with 0.1 M NaOH. SABSL was purified using an affinity column coupled with an antibody against SABSL. The purified antigen was hydrolyzed with 2 M HCl and the hydrolyzate was analyzed by thin-layer chromatography and enzymatic analysis. The results showed that SABSL contains glycerol, phosphate, glycerophosphate, D-galactose and D-glucose. D-Galactose and D-glucose accounted for 4.7% and 0.1% of the composition, respectively. Melibiose, but not mannose, inhibited the precipitation reaction. Intense precipitation reactions were obtained with fractions which did not bind to the ConA-column. These results indicate that the immunodominant component of the SABSL is galactose and the SABSL determinant is most probably a galactosylated glycerol teichoic acid. The antiserum raised against the beer spoilage strain L. brevis 578 could distinguish between Pediococcus beer spoilers and non-spoilers in precipitation reactions.

  18. Conversion of rice straw to bio-based chemicals: an integrated process using Lactobacillus brevis

    PubMed Central

    Block, David E.; Shoemaker, Sharon P.; Mills, David A.

    2010-01-01

    Commercialization of lignocellulosic biomass as a feedstock for bio-based chemical production is problematic due to the high processing costs of pretreatment and saccharifying enzymes combined with low product yields. Such low product yield can be attributed, in large part, to the incomplete utilization of the various carbohydrate sugars found in the lignocellulosic biomass. In this study, we demonstrate that Lactobacillus brevis is able to simultaneously metabolize all fermentable carbohydrates in acid pre-processed rice straw hydrolysate, thereby allowing complete utilization of all released sugars. Inhibitors present in rice straw hydrolysate did not affect lactic acid production. Moreover, the activity of exogenously added cellulases was not reduced in the presence of growing cultures of L. brevis. These factors enabled the use of L. brevis in a process termed simultaneous saccharification and mixed sugar fermentation (SSMSF). In SSMSF with L. brevis, sugars present in rice straw hydrolysate were completely utilized while the cellulase maintained its maximum activity due to the lack of feedback inhibition from glucose and/or cellobiose. By comparison to a sequential hydrolysis and fermentation process, SSMSF reduced operation time and the amount of cellulase enzyme necessary to produce the same amount of lactic acid. PMID:20084509

  19. Membrane-Bound ATPase Contributes to Hop Resistance of Lactobacillus brevis

    PubMed Central

    Sakamoto, Kanta; van Veen, H. W.; Saito, Hiromi; Kobayashi, Hiroshi; Konings, Wil N.

    2002-01-01

    The activity of the membrane-bound H+-ATPase of the beer spoilage bacterium Lactobacillus brevis ABBC45 increased upon adaptation to bacteriostatic hop compounds. The ATPase activity was optimal around pH 5.6 and increased up to fourfold when L. brevis was exposed to 666 μM hop compounds. The extent of activation depended on the concentration of hop compounds and was maximal at the highest concentration tested. The ATPase activity was strongly inhibited by N,N′-dicyclohexylcarbodiimide, a known inhibitor of FoF1-ATPase. Western blots of membrane proteins of L. brevis with antisera raised against the α- and β-subunits of FoF1-ATPase from Enterococcus hirae showed that there was increased expression of the ATPase after hop adaptation. The expression levels, as well as the ATPase activity, decreased to the initial nonadapted levels when the hop-adapted cells were cultured further without hop compounds. These observations strongly indicate that proton pumping by the membrane-bound ATPase contributes considerably to the resistance of L. brevis to hop compounds. PMID:12406727

  20. Bioconversion of flavones during fermentation in milk containing Scutellaria baicalensis extract by Lactobacillus brevis.

    PubMed

    Xu, Chen; Ji, Geun-Eog

    2013-10-28

    Scutellaria baicalensis (SB), a traditional herb with high pharmacological value, contains more than 10% flavone by weight. To improve the biological activity of flavones in SB, we aimed to enhance the bioconversion of baicalin (BG) to baicalein (B) and wogonoside (WG) to wogonin (W) in SB during fermentation using beta-glucuronidase produced from Lactobacillus brevis RO1. After activation, L. brevis RO1 was cultured in milk containing SB root extract with various carbon or nitrogen sources at 37°C for 72 h. During fermentation, the growth patterns of L. brevis RO1 and changes in the flavone content were assessed using thin-layer chromatography and high-performance liquid chromatography. After 72 h of fermentation, the concentrations of B and W in the control group increased by only 0.15 and 0.12 mM, respectively, whereas they increased by 0.57 and 0.24 mM in the fish peptone group. The production of B and W was enhanced by the addition of 0.4% fish peptone, which not only improved the growth of L. brevis RO1 (p < 0.001) but also enhanced the bioconversion of flavones. In conclusion, the bioconversion of flavones in SB may provide a potential application for the enhancement of the functional components in SB.

  1. Genome Sequence of Rapid Beer-Spoiling Isolate Lactobacillus brevis BSO 464

    PubMed Central

    Bergsveinson, Jordyn; Pittet, Vanessa; Ewen, Emily; Baecker, Nina

    2015-01-01

    The genome of brewery-isolate Lactobacillus brevis BSO 464 was sequenced and assembly produced a chromosome and eight plasmids. This bacterium tolerates dissolved CO2/pressure and can rapidly spoil packaged beer. This genome is useful for analyzing the genetics associated with beer spoilage by lactic acid bacteria. PMID:26634759

  2. Genome Sequence of Rapid Beer-Spoiling Isolate Lactobacillus brevis BSO 464.

    PubMed

    Bergsveinson, Jordyn; Pittet, Vanessa; Ewen, Emily; Baecker, Nina; Ziola, Barry

    2015-12-03

    The genome of brewery-isolate Lactobacillus brevis BSO 464 was sequenced and assembly produced a chromosome and eight plasmids. This bacterium tolerates dissolved CO2/pressure and can rapidly spoil packaged beer. This genome is useful for analyzing the genetics associated with beer spoilage by lactic acid bacteria.

  3. Electrochemical sandwich assay for attomole analysis of DNA and RNA from beer spoilage bacteria Lactobacillus brevis.

    PubMed

    Shipovskov, Stepan; Saunders, Aaron M; Nielsen, Jesper S; Hansen, Majken H; Gothelf, Kurt V; Ferapontova, Elena E

    2012-01-01

    Attomole (10(-18)mol) levels of RNA and DNA isolated from beer spoilage bacterial cells Lactobacillus brevis have been detected by the electrochemical sandwich DNA hybridization assay exploiting enzymatic activity of lipase. DNA sequences specific exclusively to L. brevis DNA and RNA were selected and used for probe and target DNA design. The assay employs magnetic beads (MB) modified with a capture DNA sequence and a reporter DNA probe labeled with the enzyme, both made to be highly specific for L. brevis DNA. Lipase-labeled DNAs captured on MBs in the sandwich assay were collected on gold electrodes modified with a ferrocene (Fc)-terminated SAM formed by aliphatic esters. Lipase hydrolysis of the ester bond released a fraction of the Fc redox active groups from the electrode surface, decreasing the electrochemical signal from the surface-confined Fc. The assay, shown to be efficient for analysis of short synthetic DNA sequences, was ineffective with genomic double stranded bacterial DNA, but it allowed down to 16 amole detection of 1563 nts long RNA, isolated from bacterial ribosomes without the need for PCR amplification, and single DNA strands produced from ribosomal RNA. No interference from E. coli RNA was registered. The assay allowed analysis of 400 L. brevis cells isolated from 1L of beer, which fits the "alarm signal" range (from 1 to 100 cells per 100mL).

  4. Membrane-bound ATPase contributes to hop resistance of Lactobacillus brevis.

    PubMed

    Sakamoto, Kanta; Van Veen, H W; Saito, Hiromi; Kobayashi, Hiroshi; Konings, Wil N

    2002-11-01

    The activity of the membrane-bound H+-ATPase of the beer spoilage bacterium Lactobacillus brevis ABBC45 increased upon adaptation to bacteriostatic hop compounds. The ATPase activity was optimal around pH 5.6 and increased up to fourfold when L. brevis was exposed to 666 microM hop compounds. The extent of activation depended on the concentration of hop compounds and was maximal at the highest concentration tested. The ATPase activity was strongly inhibited by N,N'-dicyclohexylcarbodiimide, a known inhibitor of FoF1-ATPase. Western blots of membrane proteins of L. brevis with antisera raised against the alpha- and beta-subunits of FoF1-ATPase from Enterococcus hirae showed that there was increased expression of the ATPase after hop adaptation. The expression levels, as well as the ATPase activity, decreased to the initial nonadapted levels when the hop-adapted cells were cultured further without hop compounds. These observations strongly indicate that proton pumping by the membrane-bound ATPase contributes considerably to the resistance of L. brevis to hop compounds.

  5. Alternative Reproductive Tactics in the Shell-Brooding Lake Tanganyika Cichlid Neolamprologus brevis

    PubMed Central

    Ota, Kazutaka; Aibara, Mitsuto; Morita, Masaya; Awata, Satoshi; Hori, Michio; Kohda, Masanori

    2012-01-01

    Alternative reproductive tactics (ARTs) are found in several Lake Tanganyika shell-brooding cichlids. Field studies were conducted in the Wonzye population to examine reproductive ecology and ARTs in the Lake Tanganyika shell-brooding cichlid Neolamprologus brevis. We discovered that this fish occurred in both rocky- and sandy-bottom habitats, but in rocky habitats, brood-caring females exclusively occurred in shell-patches that another cichlid species created. All N. brevis of both sexes in the patches were sexually mature, whereas immature males and females with unripe eggs were found frequently in sandy-bottom habitats. Males in sandy-bottom habitats were smaller, but fed more frequently and were in better somatic condition than males in the patches. Similar tendency was found in females. This indicates that N. brevis uses different habitats depending on the stage of its life history, with migration from sandy-bottom habitats to the shell-patches for reproduction. Males in the patches exhibited different behavior patterns: floating above the patches and lying in the patches. The former was larger, more aggressive, and invested less in gonads (relative to body size) than the latter. These results accord with those of other shell-brooding Lake Tanganyika cichlids with ARTs, and they therefore suggest the presence of ARTs in N. brevis. PMID:22888463

  6. Gene cloning, expression, and characterization of phenolic acid decarboxylase from Lactobacillus brevis RM84.

    PubMed

    Landete, José María; Rodríguez, Héctor; Curiel, José Antonio; de las Rivas, Blanca; Mancheño, José Miguel; Muñoz, Rosario

    2010-06-01

    Phenolic acid decarboxylase (PAD) catalyzes the synthesis of vinyl phenols from hydroxycinnamic acids. The gene encoding PAD from Lactobacillus brevis was cloned and expressed as a fusion protein in Escherichia coli. The recombinant PAD enzyme is a heat-labile enzyme that functions optimally at 22 degrees C and pH 6.0. The purified enzyme did not show thermostability at temperatures above 22 degrees C. L. brevis PAD is able to decarboxylate exclusively the hydroxycinnamic acids, such as p-coumaric, caffeic, and ferulic acids, with K (m) values of 0.98, 0.96, and 0.78 mM, respectively. The substrate specificity exhibited by L. brevis PAD is similar to the PAD isolated from Bacillus subtilis and B. pumilus, but different from that of L. plantarum and Pediococcus pentosaceus. As the C-terminal region may be involved in determining PAD substrate specificity and catalytic capacity, amino acid differences among these proteins could explain the differences observed. The substrate specificity shown by L. brevis PAD shows promise for the synthesis of high-added value products from plant wastes.

  7. Comparative proteomic profiling of soleus, extensor digitorum longus, flexor digitorum brevis and interosseus muscles from the mdx mouse model of Duchenne muscular dystrophy

    PubMed Central

    CARBERRY, STEVEN; BRINKMEIER, HEINRICH; ZHANG, YAXIN; WINKLER, CLAUDIA K.; OHLENDIECK, KAY

    2013-01-01

    Duchenne muscular dystrophy is due to genetic abnormalities in the dystrophin gene and represents one of the most frequent genetic childhood diseases. In the X-linked muscular dystrophy (mdx) mouse model of dystrophinopathy, different subtypes of skeletal muscles are affected to a varying degree albeit the same single base substitution within exon 23 of the dystrophin gene. Thus, to determine potential muscle subtype-specific differences in secondary alterations due to a deficiency in dystrophin, in this study, we carried out a comparative histological and proteomic survey of mdx muscles. We intentionally included the skeletal muscles that are often used for studying the pathomechanism of muscular dystrophy. Histological examinations revealed a significantly higher degree of central nucleation in the soleus and extensor digitorum longus muscles compared with the flexor digitorum brevis and interosseus muscles. Muscular hypertrophy of 20–25% was likewise only observed in the soleus and extensor digitorum longus muscles from mdx mice, but not in the flexor digitorum brevis and interosseus muscles. For proteomic analysis, muscle protein extracts were separated by fluorescence two-dimensional (2D) gel electrophoresis. Proteins with a significant change in their expression were identified by mass spectrometry. Proteomic profiling established an altered abundance of 24, 17, 19 and 5 protein species in the dystrophin-deficient soleus, extensor digitorum longus, flexor digitorum brevis and interosseus muscle, respectively. The key proteomic findings were verified by immunoblot analysis. The identified proteins are involved in the contraction-relaxation cycle, metabolite transport, muscle metabolism and the cellular stress response. Thus, histological and proteomic profiling of muscle subtypes from mdx mice indicated that distinct skeletal muscles are differentially affected by the loss of the membrane cytoskeletal protein, dystrophin. Varying degrees of perturbed protein

  8. Comparative proteomic profiling of soleus, extensor digitorum longus, flexor digitorum brevis and interosseus muscles from the mdx mouse model of Duchenne muscular dystrophy.

    PubMed

    Carberry, Steven; Brinkmeier, Heinrich; Zhang, Yaxin; Winkler, Claudia K; Ohlendieck, Kay

    2013-09-01

    Duchenne muscular dystrophy is due to genetic abnormalities in the dystrophin gene and represents one of the most frequent genetic childhood diseases. In the X-linked muscular dystrophy (mdx) mouse model of dystrophinopathy, different subtypes of skeletal muscles are affected to a varying degree albeit the same single base substitution within exon 23 of the dystrophin gene. Thus, to determine potential muscle subtype-specific differences in secondary alterations due to a deficiency in dystrophin, in this study, we carried out a comparative histological and proteomic survey of mdx muscles. We intentionally included the skeletal muscles that are often used for studying the pathomechanism of muscular dystrophy. Histological examinations revealed a significantly higher degree of central nucleation in the soleus and extensor digitorum longus muscles compared with the flexor digitorum brevis and interosseus muscles. Muscular hypertrophy of 20-25% was likewise only observed in the soleus and extensor digitorum longus muscles from mdx mice, but not in the flexor digitorum brevis and interosseus muscles. For proteomic analysis, muscle protein extracts were separated by fluorescence two-dimensional (2D) gel electrophoresis. Proteins with a significant change in their expression were identified by mass spectrometry. Proteomic profiling established an altered abundance of 24, 17, 19 and 5 protein species in the dystrophin-deficient soleus, extensor digitorum longus, flexor digitorum brevis and interosseus muscle, respectively. The key proteomic findings were verified by immunoblot analysis. The identified proteins are involved in the contraction-relaxation cycle, metabolite transport, muscle metabolism and the cellular stress response. Thus, histological and proteomic profiling of muscle subtypes from mdx mice indicated that distinct skeletal muscles are differentially affected by the loss of the membrane cytoskeletal protein, dystrophin. Varying degrees of perturbed protein

  9. Potential impact of an exceptional bloom of Karenia mikimotoi on dissolved oxygen levels in waters off western Ireland.

    PubMed

    O'Boyle, Shane; McDermott, Georgina; Silke, Joe; Cusack, Caroline

    2016-03-01

    In the summer of 2005 an exceptional bloom of the dinoflagellate Karenia mikimotoi occurred along Ireland's Atlantic seaboard and was associated with the mass mortality of both benthic and pelagic marine life. Oxygen depletion, cellular toxicity and physical smothering, are considered to be the main factors involved in mortality. In this paper we use a theoretical approach based on stoichiometry (the Anderson ratio) and an average K. mikimotoi cellular carbon content of 329pgCcell(-1) (n=20) to calculate the carbonaceous and nitrogenous oxygen demand following bloom collapse. The method was validated against measurements of biochemical oxygen demand and K. mikimotoi cell concentration. The estimated potential oxygen utilisation (POU) was in good agreement with field observations across a range of cell concentrations. The magnitude of POU following bloom collapse, with the exception of three coastal areas, was considered insufficient to cause harm to most marine organisms. This indicates that the widespread occurrence of mortality was primarily due to other factors such as cellular toxicity and/or mucilage production, and not oxygen depletion or related phenomena. In Donegal Bay, Kilkieran Bay and inner Dingle Bay, where cell densities were in the order of 10(6)cellsL(-1), estimated POU was sufficient to cause hypoxia. Of the three areas, Donegal Bay is considered to be the most vulnerable due to its hydrographic characteristics (seasonally stratified, weak residual flow) and hypoxic conditions (2.2mgL(-1) O2) were directly observed in the Bay post bloom collapse. Here, depending on the time of bloom collapse, depressed DO levels could persist for weeks and continue to have a potentially chronic impact on the Bay.

  10. Identification of ethylparaben as the antimicrobial substance produced by Brevibacillus brevis FJAT-0809-GLX.

    PubMed

    Jianmei, Che; Bo, Liu; Zheng, Chen; Huai, Shi; Guohong, Liu; Cibin, Ge

    2015-03-01

    In this study, crude antimicrobial extract from the culture supernatant of Brevibacillus brevis FJAT-0809-GLX was extracted, and its antimicrobial activity was investigated with the agar diffusion method. The results showed that the antimicrobial activity of the culture supernatant of B. brevis FJAT-0809-GLX increased with the extension of the incubation time of B. brevis FJAT-0809-GLX. The antimicrobial spectrum assays showed that this crude antimicrobial extract from culture supernatant of B. brevis FJAT-0809-GLX could inhibit the growth of both bacteria and fungi. A heat stability test was performed, and different temperatures (30°C, 50°C and 70°C) did not affect the antibiotic activity of this crude antimicrobial extract. The crude antimicrobial extract was also tolerable to changes in pH levels. Its antibiotic activity against Escherichia coli was stable at pH 1 to pH 11, with zone sizes ranging from 18.46mm to 22.19mm. Almost all of the crude extracts extracted using different solvents showed variable degrees of inhibition zones against E. coli, with zone sizes ranging from 17.29mm to 19.62mm, except petroleum ether and butanol extracts, which were found to be completely inactive. Purification of the antimicrobial components was carried out using a column chromatographic technique with column chromatography grade silica gel and analyzed by an Agilent 7890A Network GC system. The separated compound was identified as ethylparaben, with a retention time of 21.980min and a relative amount of 95.50%. The antimicrobial activity of ethylparaben on different types of bacteria and fungi was investigated, and ethylparaben was shown to inhibit different types of microbes to different extents. To the best of our knowledge, this is the first report demonstrating that the bacterium B. brevis could produce ethylparaben.

  11. Production of gamma-aminobutyric acid by Lactobacillus brevis NCL912 using fed-batch fermentation

    PubMed Central

    2010-01-01

    Background Gamma-aminobutyric acid is a major inhibitory neurotransmitter in mammalian brains, and has several well-known physiological functions. Lactic acid bacteria possess special physiological activities and are generally regarded as safe. Therefore, using lactic acid bacteria as cell factories for gamma-aminobutyric acid production is a fascinating project and opens up a vast range of prospects for making use of GABA and LAB. We previously screened a high GABA-producer Lactobacillus brevis NCL912 and optimized its fermentation medium composition. The results indicated that the strain showed potential in large-scale fermentation for the production of gamma-aminobutyric acid. To increase the yielding of GABA, further study on the fermentation process is needed before the industrial application in the future. In this article we investigated the impacts of pyridoxal-5'-phosphate, pH, temperature and initial glutamate concentration on gamma-aminobutyric acid production by Lactobacillus brevis NCL912 in flask cultures. According to the data obtained in the above, a simple and effective fed-batch fermentation method was developed to highly efficiently convert glutamate to gamma-aminobutyric acid. Results Pyridoxal-5'-phosphate did not affect the cell growth and gamma-aminobutyric acid production of Lb. brevis NCL912. Temperature, pH and initial glutamate concentration had significant effects on the cell growth and gamma-aminobutyric acid production of Lb. brevis NCL912. The optimal temperature, pH and initial glutamate concentration were 30-35°C, 5.0 and 250-500 mM. In the following fed-batch fermentations, temperature, pH and initial glutamate concentration were fixed as 32°C, 5.0 and 400 mM. 280.70 g (1.5 mol) and 224.56 g (1.2 mol) glutamate were supplemented into the bioreactor at 12 h and 24 h, respectively. Under the selected fermentation conditions, gamma-aminobutyric acid was rapidly produced at the first 36 h and almost not produced after then. The gamma

  12. Colicin E2 Expression in Lactobacillus brevis DT24, A Vaginal Probiotic Isolate, against Uropathogenic Escherichia coli.

    PubMed

    Trivedi, Disha; Jena, Prasant Kumar; Seshadri, Sriram

    2014-01-01

    Novel therapeutic approaches are needed to combat the urinary tract infection in women. During menstruation elevated protein concentration and increase in oxygen and carbon dioxide concentrations with decrease in vaginal Lactobacilli all together contribute to urinary tract infections. Lactobacillus species are a predominant member of the vaginal microflora and are critical in the prevention of a number of urogenital diseases. In order to increase antimicrobial potential of vaginal Lactobacilli, bacteriocin colicin E2 which has specific activity against uropathogenic Escherichia coli has been overexpressed in vaginal probiotic Lactobacillus brevis DT24. Recombinant Lactobacillus brevis DT24 expressing colicin E2 showed much higher inhibitory activity against uropathogenic Escherichia coli than wild type L. brevis DT24 in vitro. Efficacy of probiotic Lactobacillus brevis DT24 expressing colicin E2 protein is required for further in vivo evaluation.

  13. Colicin E2 Expression in Lactobacillus brevis DT24, A Vaginal Probiotic Isolate, against Uropathogenic Escherichia coli

    PubMed Central

    Trivedi, Disha

    2014-01-01

    Novel therapeutic approaches are needed to combat the urinary tract infection in women. During menstruation elevated protein concentration and increase in oxygen and carbon dioxide concentrations with decrease in vaginal Lactobacilli all together contribute to urinary tract infections. Lactobacillus species are a predominant member of the vaginal microflora and are critical in the prevention of a number of urogenital diseases. In order to increase antimicrobial potential of vaginal Lactobacilli, bacteriocin colicin E2 which has specific activity against uropathogenic Escherichia coli has been overexpressed in vaginal probiotic Lactobacillus brevis DT24. Recombinant Lactobacillus brevis DT24 expressing colicin E2 showed much higher inhibitory activity against uropathogenic Escherichia coli than wild type L. brevis DT24 in vitro. Efficacy of probiotic Lactobacillus brevis DT24 expressing colicin E2 protein is required for further in vivo evaluation. PMID:24649377

  14. Molecular cloning of a putative divalent-cation transporter gene as a new genetic marker for the identification of Lactobacillus brevis strains capable of growing in beer.

    PubMed

    Hayashi, N; Ito, M; Horiike, S; Taguchi, H

    2001-05-01

    Random amplified polymorphic DNA (RAPD) PCR analysis of Lactobacillus brevis isolates from breweries revealed that one of the random primers could distinguish beer-spoilage strains of L. brevis from nonspoilage strains. The 1.1-kb DNA fragment amplified from all beer-spoilers included one open reading frame, termed hitA (hop-inducible cation transporter), which encodes an integral membrane protein with 11 putative trans-membrane domains and a binding protein-dependent transport signature of a non-ATP binding membrane transporter common to several prokaryotic and eukaryotic transporters. The hitA polypeptide is homologous to the natural resistance-associated macrophage protein (Nramp) family characterized as divalent-cation transport proteins in many prokaryotic and eukaryotic organisms. Northern blot analysis indicated that the hitA transcripts are expressed in cells cultivated in MRS broth supplemented with hop bitter compounds, which act as mobile-carrier ionophores, dissipating the trans-membrane pH gradient in bacteria sensitive to the hop bitter compounds by exchanging H+ for cellular divalent cations such as Mn2+. This suggests that the hitA gene products may play an important role in making the bacteria resistant to hop bitter compounds in beer by transporting metal ions such as Mn2+ into cells that no longer maintain the proton gradient.

  15. Quantification of cyclic dipeptides from cultures of Lactobacillus brevis R2Δ by HRGC/MS using stable isotope dilution assay.

    PubMed

    Axel, Claudia; Zannini, Emanuele; Arendt, Elke K; Waters, Deborah M; Czerny, Michael

    2014-04-01

    Lactic acid bacteria (LAB) play an important role as natural preservatives in fermented food and beverage systems, reducing the application of chemical additives. Thus, investigating their antifungal compounds, such as cyclic dipeptides, has gained prominence. Previous research has primarily focussed on isolation of these compounds. However, their precise quantification will provide further information regarding their antifungal performance in a complex system. To address this, deuterated labelled standards of the cyclic dipeptides cyclo(Leu-Pro), cyclo(Pro-Pro), cyclo(Met-Pro) and cyclo(Phe-Pro) were synthesized, and stable isotope dilution assays were developed, enabling an accurate quantification of cyclo(Leu-Pro), cyclo(Pro-Pro), cyclo(Met-Pro) and cyclo(Phe-Pro) in MRS-broth and wort. Quantitative results showed that, in the Lactobacillus brevis R2Δ fermented MRS-broth, the concentrations of cyclo(Leu-Pro), cyclo(Pro-Pro) and cyclo(Phe-Pro) were significantly higher (P < 0.05), than in wort for cyclo (Leu-Pro) when compared with their controls. This indicates that the formation of these three cyclic dipeptides is related to L. brevis R2Δ metabolism. Furthermore, this represents the first report of cyclic dipeptides quantification using stable isotope dilution assays in LAB cultures both in vitro and in a food system.

  16. Effect of Lactobacillus brevis ATCC 8287 as a feeding supplement on the performance and immune function of piglets.

    PubMed

    Lähteinen, Tanja; Lindholm, Agneta; Rinttilä, Teemu; Junnikkala, Sami; Kant, Ravi; Pietilä, Taija E; Levonen, Katri; von Ossowski, Ingemar; Solano-Aguilar, Gloria; Jakava-Viljanen, Miia; Palva, Airi

    2014-03-15

    Lactobacillus brevis ATCC 8287, a surface (S-layer) strain, possesses a variety of functional properties that make it both a potential probiotic and a good vaccine vector candidate. With this in mind, our aim was to study the survival of L. brevis in the porcine gut and investigate the effect of this strain on the growth and immune function of recently weaned piglets during a feeding trial. For this, 20 piglets were divided evenly into a treatment and a control group. Piglets in the treatment group were fed L. brevis cells (1×10(10)) daily for three weeks, whereas those in the control group were provided an equivalent amount of probiotic-free placebo. For assessing the impact of L. brevis supplementation during the feeding trial, health status and weight gain of the piglets were monitored, pre- and post-trial samples of serum and feces were obtained, and specimens of the small and large intestinal mucosa and digesta were collected at slaughter. The results we obtained indicated that L. brevis-supplemented feeding induced a non-significant increase in piglet body weight and caused no change in the morphology of the intestinal mucosa. L. brevis cells were found to localize mainly in the large intestine, but they could not be isolated from feces. To a lesser extent, L. brevis was detected in the small intestine, although there was no specific attachment to the Peyer's patches. Changes in total serum IgG and IgA concentrations were not caused by supplemented L. brevis and no measurable rise in L. brevis-specific IgG was observed. However, analysis of cytokine gene expression in intestinal mucosa revealed downregulation of TGF-β1 in the ileum and upregulation of IL-6 in the cecum in the L. brevis-supplemented group. Based on the results from this study, we conclude that whereas L. brevis appears to have some intestinal immunomodulatory effects, the ability of this strain to survive and colonize within the porcine gut appears to be limited.

  17. Fructophilic Lactobacillus kunkeei and Lactobacillus brevis isolated from fresh flowers, bees and bee-hives.

    PubMed

    Neveling, Deon P; Endo, Akihito; Dicks, Leon M T

    2012-11-01

    Two-hundred-and-thirty-six isolates were collected from fresh flowers, bees and bee-hives. Of these, 20 isolates preferred D-fructose as carbon source, produced lactic acid and acetic acid but trace amounts of ethanol and were classified as fructophilic. Poor growth was recorded when strains were incubated anaerobically in the presence of D-glucose as sole carbon source. Good growth was, however, recorded when D-glucose was metabolized in the presence of external electron acceptors such as fructose, pyruvate and oxygen. Nineteen of the strains were classified as Lactobacillus kunkeei and one as Lactobacillus brevis based on phenotypic characteristics, 16S rRNA sequences, recA sequences and DNA homology. This is the first description of a fructophilic strain of L. brevis.

  18. 1,3-Propanediol:NAD+ oxidoreductases of Lactobacillus brevis and Lactobacillus buchneri.

    PubMed

    Veiga-da-Cunha, M; Foster, M A

    1992-06-01

    In the cofermentation of glycerol with a sugar by Lactobacillus brevis and Lactobacillus buchneri, a 1,3-propanediol:NAD+ oxidoreductase provides an additional method of NADH disposal. The enzyme has been purified from both L. brevis B22 and L. buchneri B190 and found to have properties very similar to those reported for the enzyme from Klebsiella pneumoniae. The enzymes required Mn2+ and are probably octamers with a molecular mass of 350 kDa. Although not absolutely specific for 1,3-propanediol when tested as dehydrogenases, the enzymes have less than 10% activity with glycerol, ethanol, and 1,2-propanediol. These properties contrast sharply with those of a protein isolated from another Lactobacillus species (L. reuteri) that ferments glycerol with glucose and previously designated a 1,3-propanediol dehydrogenase.

  19. 1,3-Propanediol:NAD+ oxidoreductases of Lactobacillus brevis and Lactobacillus buchneri.

    PubMed Central

    Veiga-da-Cunha, M; Foster, M A

    1992-01-01

    In the cofermentation of glycerol with a sugar by Lactobacillus brevis and Lactobacillus buchneri, a 1,3-propanediol:NAD+ oxidoreductase provides an additional method of NADH disposal. The enzyme has been purified from both L. brevis B22 and L. buchneri B190 and found to have properties very similar to those reported for the enzyme from Klebsiella pneumoniae. The enzymes required Mn2+ and are probably octamers with a molecular mass of 350 kDa. Although not absolutely specific for 1,3-propanediol when tested as dehydrogenases, the enzymes have less than 10% activity with glycerol, ethanol, and 1,2-propanediol. These properties contrast sharply with those of a protein isolated from another Lactobacillus species (L. reuteri) that ferments glycerol with glucose and previously designated a 1,3-propanediol dehydrogenase. Images PMID:1622279

  20. Acute iliopsoas and adductor brevis abscesses presenting with proximal leg muscle weakness.

    PubMed

    Devetag Chalaupka, F

    2006-06-01

    Pyomyositis is a bacterial infection of skeletal muscle. We describe the clinical case of a 77-year-old woman affected by gait disturbance, repetitive falls, low back pain and left thigh and groin pain, but without symptoms of systemic infection. Computed tomography and magnetic resonance imaging of the abdomen and pelvis showed abscesses in the left psoas and adductor brevis muscles. Investigations of urogenital tract and gastrointestinal system were normal. Systemic antibiotic treatment alone was not efficient, while surgical drainage improved the clinical picture. The aetiological organism, isolated from the abscess, was Staphylococcus aureus. We suggest that this patient had a primary pyomyositis rather than a secondary form. This is the first report of concomitant abscesses of psoas and adductor brevis muscles with early neurological involvement.

  1. Optimization of γ-amino butyric acid production in a newly isolated Lactobacillus brevis.

    PubMed

    Binh, Tran Thi Thanh; Ju, Wan-Taek; Jung, Woo-Jin; Park, Ro-Dong

    2014-01-01

    An isolate from kimchi, identified as Lactobacillus brevis, accumulated γ-aminobutyric acid (GABA), a major inhibitory neurotransmitter, in the culture medium. Optimal culture conditions for growth of L. brevis and production of GABA were 6 % (w/v) l-glutamic acid, 4 % (w/v) maltose, 2 % (w/v) yeast extract, 1 % (w/v) NaCl, 1 % (w/v) CaCl2, 2 g Tween 80/l, and 0.02 mM pyridoxal 5′-phosphate at initial pH 5.25 and 37 °C. GABA reached 44.4 g/l after 72 h cultivation with a conversion rate 99.7 %, based on the amount (6 %) of l-glutamic acid added. GABA was purified using ion exchange column chromatography with 70 % recovery and 97 % purity.

  2. Longitudinal split tear of the extensor pollicis brevis tendon: report of 2 cases.

    PubMed

    Kroonen, Leo T; Ferguson, Christopher; Ketschke, Rhett A

    2015-02-01

    Two patients presented with radial-sided wrist pain and longitudinal split tears of the extensor pollicis brevis tendon. Surgical debridement and repair was performed on the first patient with good results. Early diagnosis in the second patient led to successful treatment with immobilization alone. If diagnostic maneuvers for de Quervain tenosynovitis produce pain in a location other than the radial styloid, advanced imaging should be considered to identify other anatomic causes for the pain.

  3. Transcriptional Analysis of Lactobacillus brevis to N-Butanol and Ferulic Acid Stress Responses

    PubMed Central

    Winkler, James; Kao, Katy C.

    2011-01-01

    Background The presence of anti-microbial phenolic compounds, such as the model compound ferulic acid, in biomass hydrolysates pose significant challenges to the widespread use of biomass in conjunction with whole cell biocatalysis or fermentation. Currently, these inhibitory compounds must be removed through additional downstream processing or sufficiently diluted to create environments suitable for most industrially important microbial strains. Simultaneously, product toxicity must also be overcome to allow for efficient production of next generation biofuels such as n-butanol, isopropanol, and others from these low cost feedstocks. Methodology and Principal Findings This study explores the high ferulic acid and n-butanol tolerance in Lactobacillus brevis, a lactic acid bacterium often found in fermentation processes, by global transcriptional response analysis. The transcriptional profile of L. brevis reveals that the presence of ferulic acid triggers the expression of currently uncharacterized membrane proteins, possibly in an effort to counteract ferulic acid induced changes in membrane fluidity and ion leakage. In contrast to the ferulic acid stress response, n-butanol challenges to growing cultures primarily induce genes within the fatty acid synthesis pathway and reduced the proportion of 19∶1 cyclopropane fatty acid within the L. brevis membrane. Both inhibitors also triggered generalized stress responses. Separate attempts to alter flux through the Escherichia coli fatty acid synthesis by overexpressing acetyl-CoA carboxylase subunits and deleting cyclopropane fatty acid synthase (cfa) both failed to improve n-butanol tolerance in E. coli, indicating that additional components of the stress response are required to confer n-butanol resistance. Conclusions Several promising routes for understanding both ferulic acid and n-butanol tolerance have been identified from L. brevis gene expression data. These insights may be used to guide further engineering of

  4. β-Glucuronidase from Lactobacillus brevis useful for baicalin hydrolysis belongs to glycoside hydrolase family 30.

    PubMed

    Sakurama, Haruko; Kishino, Shigenobu; Uchibori, Yoshie; Yonejima, Yasunori; Ashida, Hisashi; Kita, Keiko; Takahashi, Satomi; Ogawa, Jun

    2014-05-01

    Baicalin (baicalein 7-O-β-D-glucuronide) is one of the major flavonoid glucuronides found in traditional herbal medicines. Because its aglycone, baicalein, is absorbed more quickly and shows more effective properties than baicalin, the conversion of baicalin into baicalein by β-glucuronidase (GUS) has drawn the attention of researchers. Recently, we have found that Lactobacillus brevis subsp. coagulans can convert baicalin to baicalein. Therefore, we aimed to identify and characterize the converting enzyme from L. brevis subsp. coagulans. First, we purified this enzyme from the cell-free extracts of L. brevis subsp. coagulans and cloned its gene. Surprisingly, this enzyme was found to be a GUS belonging to glycoside hydrolase (GH) family 30 (designated as LcGUS30), and its amino acid sequence has little similarity with any GUS belonging to GH families 1, 2, and 79 that have been reported so far. We then established a high-level expression and simple purification system of the recombinant LcGUS30 in Escherichia coli. The detailed analysis of the substrate specificity revealed that LcGUS30 has strict specificity toward glycon but not toward aglycones. Interestingly, LcGUS30 prefers baicalin rather than estrone 3-(β-D-glucuronide), one of the human endogenous steroid hormones. These results indicated that L. brevis subsp. coagulans and LcGUS30 should serve as powerful tools for the construction of a safe bioconversion system for baicalin. In addition, we propose that this novel type of GUS forms a new group in subfamily 3 of GH family 30.

  5. Genome Sequence of Lactobacillus brevis Strain D6, Isolated from Smoked Fresh Cheese

    PubMed Central

    Uroić, Ksenija; Hynönen, Ulla; Kos, Blaženka; Šušković, Jagoda

    2016-01-01

    The autochthonous Lactobacillus brevis strain D6, isolated from smoked fresh cheese, carries a 45-kDa S-layer protein. Strain D6 has shown adhesion to extracellular matrix proteins and to Caco-2 intestinal epithelial cells, as well as immunomodulatory potential and beneficial milk technological properties. Hence, it could be used as a potential probiotic starter culture for cheese production. PMID:27056237

  6. [Reconstruction of a chronic Achilles tendon lesion with autologous peroneus brevis graft].

    PubMed

    Estrada-Malacón, Ciro Arturo; García-Estrada, Gustavo Adolfo

    2009-01-01

    The calcaneal tendon lesion is very important due to the role of this tendon on gait performance, therefore a treatment strategy allowing the patient to resume activities of daily living as soon as possible is of the utmost importance. Treatment with a surgical approach involving the lateral peroneus brevis tendon facilitates bipodal support and immediate rehabilitation allowing the patient to resume activities of daily living as soon as possible.

  7. Distribution of the Euryhaline Squid Lolliguncula brevis in Chesapeake Bay: Effects of Selected Abiotic Factors

    DTIC Science & Technology

    2002-01-31

    significant aquatic habitats where cephalopods are poorly represented. One notable squid, the brief squid Lolliguncula brevis, is the only species of... cephalopod frequently found in low-salinity estuaries (Vecchione 1991a), where it tolerates salinities as low as 8.5‰ for brief periods (Laughlin...effects of selected abiotic factors I. K. Bartol1,*, R. Mann2, M. Vecchione3 1Department of Organismic Biology, Ecology, and Evolution , University of

  8. Polyphosphate Derived from Lactobacillus brevis Inhibits Colon Cancer Progression Through Induction of Cell Apoptosis.

    PubMed

    Sakatani, Aki; Fujiya, Mikihiro; Ueno, Nobuhiro; Kashima, Shin; Sasajima, Junpei; Moriichi, Kentaro; Ikuta, Katsuya; Tanabe, Hiroki; Kohgo, Yutaka

    2016-02-01

    Although probiotics are known to have antitumor activity, few bacteria-derived antitumor molecules have been identified. The present study explored an antitumor molecule derived from Lactobacillus brevis SBL8803 (L. brevis 8803) and the mechanisms that underlie its effects. Cell viability and apoptosis were assessed by a sulforhodamine B assay and terminal deoxynucleotidyl transferase dUTP staining, respectively. Phosphorylated extracellular signal-regulated kinase (ERK) and cleaved poly ADP-ribose polymerase (PARP) expression were detected by western blotting. The conditioned medium of L. brevis 8803 inhibited SW620 cells viability and the effect was reduced by the degradation of polyphosphate (poly P) in the conditioned medium. A xenograft model showed that poly P inhibited the growth of SW620 cells. Poly P induced the apoptosis of SW620 cells through activation of the ERK pathway. In contrast, in primary cultured cells derived from normal mouse, poly P did not affect cell viability. Probiotic-derived poly P is expected to be an antitumor drug with fewer adverse effects than conventional drugs.

  9. Identification of ecotype-specific marker genes for categorization of beer-spoiling Lactobacillus brevis.

    PubMed

    Behr, Jürgen; Geissler, Andreas J; Preissler, Patrick; Ehrenreich, Armin; Angelov, Angel; Vogel, Rudi F

    2015-10-01

    The tolerance to hop compounds, which is mainly associated with inhibition of bacterial growth in beer, is a multi-factorial trait. Any approaches to predict the physiological differences between beer-spoiling and non-spoiling strains on the basis of a single marker gene are limited. We identified ecotype-specific genes related to the ability to grow in Pilsner beer via comparative genome sequencing. The genome sequences of four different strains of Lactobacillus brevis were compared, including newly established genomes of two highly hop tolerant beer isolates, one strain isolated from faeces and one published genome of a silage isolate. Gene fragments exclusively occurring in beer-spoiling strains as well as sequences only occurring in non-spoiling strains were identified. Comparative genomic arrays were established and hybridized with a set of L. brevis strains, which are characterized by their ability to spoil beer. As result, a set of 33 and 4 oligonucleotide probes could be established specifically detecting beer-spoilers and non-spoilers, respectively. The detection of more than one of these marker sequences according to a genetic barcode enables scoring of L. brevis for their beer-spoiling potential and can thus assist in risk evaluation in brewing industry.

  10. Localization and Characterization of α-Glucosidase Activity in Lactobacillus brevis

    PubMed Central

    De Cort, S.; Kumara, H. M. C. Shantha; Verachtert, H.

    1994-01-01

    Lactobacillus brevis is found together with the yeast Brettanomyces lambicus during the overattenuation process in spontaneously fermented lambic beer. An isolated L. brevis strain has been shown to produce an α-glucosidase with many similarities to the glucosidase earlier found in B. lambicus. The enzyme was purified by ammonium sulfate precipitation, gel (Sephadex G-150 and Ultrogel AcA-44) filtration, and ion-exchange chromatography (DEAE-Sephadex A-50). The molecular weights of the enzyme, as determined by gel chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were about 50,000 and 60,000, respectively. Optimum catalytic activity was obtained at 40°C and pH 6.0. The enzyme showed a decrease of hydrolysis with an increase in the degree of polymerization of the substrate. The Km values for p-nitrophenyl-α-d-glucopyranoside, maltose, and maltotriose were 0.51, 3.0, and 5.2 mM, respectively. There was lack of inhibition by 0.15 mM acarbose and 0.5 M turanose, but the enzyme was inhibited by Tris (Ki value of 25 mM). The α-glucosidase of L. brevis together with the enzyme of B. lambicus seems to be a key factor in the overattenuation of lambic beer, although the involvement of other lactic acid bacteria (pediococci) cannot be excluded. Images PMID:16349368

  11. Biological valorization of pure and crude glycerol into 1,3-propanediol using a novel isolate Lactobacillus brevis N1E9.3.3.

    PubMed

    Vivek, Narisetty; Pandey, Ashok; Binod, Parameswaran

    2016-08-01

    The aim of the study was to evaluate a novel onsite enrichment approach to isolate a crude glycerol utilizing facultative anaerobic bacteria. An onsite enrichment in natural conditions resulted an isolate, Lactobacillus brevis N1E9.3.3, that can utilize glycerol and produce 1,3-propanediol with a yield of 0.89g1,3-PDO/gGlycerol and productivity of 0.78g1,3-PDO/l/h at pH-8.5 under anaerobic conditions. Batch fermentation experiments with glycerol-glucose co-fermentation strategy was carried out to evaluate the production of 1,3-propanediol and other byproducts. The effect of other carbon sources as co-substrate was also evaluated. At the optimized condition, 18.6g/l 1,3-propanediol was monitored when biodiesel industry generated crude glycerol and 2.5% glucose were used as the substrate.

  12. Contribution of the activated catalase to oxidative stress resistance and γ-aminobutyric acid production in Lactobacillus brevis.

    PubMed

    Lyu, Changjiang; Hu, Sheng; Huang, Jun; Luo, Maiqi; Lu, Tao; Mei, Lehe; Yao, Shanjing

    2016-12-05

    Lactic acid bacteria (LAB) are generally sensitive to H2O2, a compound which can paradoxically produce themselves and lead to the growth arrest and cell death. To counteract the potentially toxic effects of this compound, the gene katE encoding a heme-dependent catalase (CAT) belonging to the family of monofunctional CATs was cloned from Lactobacillus brevis CGMCC1306. The enhanced homologous CAT expression was achieved using the NICE system. L. brevis cells with overexpressed CAT showed 685-fold and 823-fold higher survival when exposed to 30mmol/L of H2O2 and long-term aerated stress (after 72h), respectively, than that of the wild type cells. Furtherly, the effects of activated CAT on GABA production in L. brevis were investigated. A GABA production level of 66.4g/L was achieved using two-step biotransformation that successively employed the growing and resting cells derived from engineering L. brevis CAT. These results demonstrated clearly that overexpression of the KatE gene in L. brevis led to a marked increased survival in oxidizing environment, and shed light on a novel feasible approach to enhance the GABA production level by improving the antioxidative properties.

  13. Characterization of a highly hop-resistant Lactobacillus brevis strain lacking hop transport.

    PubMed

    Behr, Jürgen; Gänzle, Michael G; Vogel, Rudi F

    2006-10-01

    Resistance to hops is a prerequisite for lactic acid bacteria to spoil beer. In this study we analyzed mechanisms of hop resistance of Lactobacillus brevis at the metabolism, membrane physiology, and cell wall composition levels. The beer-spoiling organism L. brevis TMW 1.465 was adapted to high concentrations of hop compounds and compared to a nonadapted strain. Upon adaptation to hops the metabolism changed to minimize ethanol stress. Fructose was used predominantly as a carbon source by the nonadapted strain but served as an electron acceptor upon adaptation to hops, with concomitant formation of acetate instead of ethanol. Furthermore, hop adaptation resulted in higher levels of lipoteichoic acids (LTA) incorporated into the cell wall and altered composition and fluidity of the cytoplasmic membrane. The putative transport protein HitA and enzymes of the arginine deiminase pathway were overexpressed upon hop adaptation. HorA was not expressed, and the transport of hop compounds from the membrane to the extracellular space did not account for increased resistance to hops upon adaptation. Accordingly, hop resistance is a multifactorial dynamic property, which can develop during adaptation. During hop adaptation, arginine catabolism contributes to energy and generation of the proton motive force until a small fraction of the population has established structural improvements. This acquired hop resistance is energy independent and involves an altered cell wall composition. LTA shields the organism from accompanying stresses and provides a reservoir of divalent cations, which are otherwise scarce as a result of their complexation by hop acids. Some of the mechanisms involved in hop resistance overlap with mechanisms of pH resistance and ethanol tolerance and as a result enable beer spoilage by L. brevis.

  14. Surface Display of Foreign Epitopes on the Lactobacillus brevis S-Layer

    PubMed Central

    Åvall-Jääskeläinen, Silja; Kylä-Nikkilä, Kari; Kahala, Minna; Miikkulainen-Lahti, Terhi; Palva, Airi

    2002-01-01

    So far, the inability to establish viable Lactobacillus surface layer (S-layer) null mutants has hampered the biotechnological applications of Lactobacillus S-layers. In this study, we demonstrate the utilization of Lactobacillus brevis S-layer subunits (SlpA) for the surface display of foreign antigenic epitopes. With an inducible expression system, L. brevis strains producing chimeric S-layers were obtained after testing of four insertion sites in the slpA gene for poliovirus epitope VP1, that comprises 10 amino acids. The epitope insertion site allowing the best surface expression was used for the construction of an integration vector carrying the gene region encoding the c-Myc epitopes from the human c-myc proto-oncogene, which is composed of 11 amino acids. A gene replacement system was optimized for L. brevis and used for the replacement of the wild-type slpA gene with the slpA-c-myc construct. A uniform S-layer, displaying on its surface the desired antigen in all of the S-layer protein subunits, was obtained. The success of the gene replacement and expression of the uniform SlpA-c-Myc recombinant S-layer was confirmed by PCR, Southern blotting MALDI-TOF mass spectrometry, whole-cell enzyme-linked immunosorbent assay, and immunofluorescence microscopy. Furthermore, the integrity of the recombinant S-layer was studied by electron microscopy, which indicated that the S-layer lattice structure was not affected by the presence of c-Myc epitopes. To our knowledge, this is the first successful expression of foreign epitopes in every S-layer subunit of a Lactobacillus S-layer while still maintaining the S-layer lattice structure. PMID:12450814

  15. Arabinoxylan oligosaccharide hydrolysis by family 43 and 51 glycosidases from Lactobacillus brevis DSM 20054.

    PubMed

    Michlmayr, Herbert; Hell, Johannes; Lorenz, Cindy; Böhmdorfer, Stefan; Rosenau, Thomas; Kneifel, Wolfgang

    2013-11-01

    Due to their potential prebiotic properties, arabinoxylan-derived oligosaccharides [(A)XOS] are of great interest as functional food and feed ingredients. While the (A)XOS metabolism of Bifidobacteriaceae has been extensively studied, information regarding lactic acid bacteria (LAB) is still limited in this context. The aim of the present study was to fill this important gap by characterizing candidate (A)XOS hydrolyzing glycoside hydrolases (GHs) identified in the genome of Lactobacillus brevis DSM 20054. Two putative GH family 43 xylosidases (XynB1 and XynB2) and a GH family 43 arabinofuranosidase (Abf3) were heterologously expressed and characterized. While the function of XynB1 remains unclear, XynB2 could efficiently hydrolyze xylooligosaccharides. Abf3 displayed high specific activity for arabinobiose but could not release arabinose from an (A)XOS preparation. However, two previously reported GH 51 arabinofuranosidases from Lb. brevis were able to specifically remove α-1,3-linked arabinofuranosyl residues from arabino-xylooligosaccharides (AXHm3 specificity). These results imply that Lb. brevis is at least genetically equipped with functional enzymes in order to hydrolyze the depolymerization products of (arabino)xylans and arabinans. The distribution of related genes in Lactobacillales genomes indicates that GH 43 and, especially, GH 51 glycosidase genes are rare among LAB and mainly occur in obligately heterofermentative Lactobacillus spp., Pediococcus spp., members of the Leuconostoc/Weissella branch, and Enterococcus spp. Apart from the prebiotic viewpoint, this information also adds new perspectives on the carbohydrate (i.e., pentose-oligomer) metabolism of LAB species involved in the fermentation of hemicellulose-containing substrates.

  16. Arabinoxylan Oligosaccharide Hydrolysis by Family 43 and 51 Glycosidases from Lactobacillus brevis DSM 20054

    PubMed Central

    Hell, Johannes; Lorenz, Cindy; Böhmdorfer, Stefan; Rosenau, Thomas; Kneifel, Wolfgang

    2013-01-01

    Due to their potential prebiotic properties, arabinoxylan-derived oligosaccharides [(A)XOS] are of great interest as functional food and feed ingredients. While the (A)XOS metabolism of Bifidobacteriaceae has been extensively studied, information regarding lactic acid bacteria (LAB) is still limited in this context. The aim of the present study was to fill this important gap by characterizing candidate (A)XOS hydrolyzing glycoside hydrolases (GHs) identified in the genome of Lactobacillus brevis DSM 20054. Two putative GH family 43 xylosidases (XynB1 and XynB2) and a GH family 43 arabinofuranosidase (Abf3) were heterologously expressed and characterized. While the function of XynB1 remains unclear, XynB2 could efficiently hydrolyze xylooligosaccharides. Abf3 displayed high specific activity for arabinobiose but could not release arabinose from an (A)XOS preparation. However, two previously reported GH 51 arabinofuranosidases from Lb. brevis were able to specifically remove α-1,3-linked arabinofuranosyl residues from arabino-xylooligosaccharides (AXHm3 specificity). These results imply that Lb. brevis is at least genetically equipped with functional enzymes in order to hydrolyze the depolymerization products of (arabino)xylans and arabinans. The distribution of related genes in Lactobacillales genomes indicates that GH 43 and, especially, GH 51 glycosidase genes are rare among LAB and mainly occur in obligately heterofermentative Lactobacillus spp., Pediococcus spp., members of the Leuconostoc/Weissella branch, and Enterococcus spp. Apart from the prebiotic viewpoint, this information also adds new perspectives on the carbohydrate (i.e., pentose-oligomer) metabolism of LAB species involved in the fermentation of hemicellulose-containing substrates. PMID:23995921

  17. Characterization of a Highly Hop-Resistant Lactobacillus brevis Strain Lacking Hop Transport

    PubMed Central

    Behr, Jürgen; Gänzle, Michael G.; Vogel, Rudi F.

    2006-01-01

    Resistance to hops is a prerequisite for lactic acid bacteria to spoil beer. In this study we analyzed mechanisms of hop resistance of Lactobacillus brevis at the metabolism, membrane physiology, and cell wall composition levels. The beer-spoiling organism L. brevis TMW 1.465 was adapted to high concentrations of hop compounds and compared to a nonadapted strain. Upon adaptation to hops the metabolism changed to minimize ethanol stress. Fructose was used predominantly as a carbon source by the nonadapted strain but served as an electron acceptor upon adaptation to hops, with concomitant formation of acetate instead of ethanol. Furthermore, hop adaptation resulted in higher levels of lipoteichoic acids (LTA) incorporated into the cell wall and altered composition and fluidity of the cytoplasmic membrane. The putative transport protein HitA and enzymes of the arginine deiminase pathway were overexpressed upon hop adaptation. HorA was not expressed, and the transport of hop compounds from the membrane to the extracellular space did not account for increased resistance to hops upon adaptation. Accordingly, hop resistance is a multifactorial dynamic property, which can develop during adaptation. During hop adaptation, arginine catabolism contributes to energy and generation of the proton motive force until a small fraction of the population has established structural improvements. This acquired hop resistance is energy independent and involves an altered cell wall composition. LTA shields the organism from accompanying stresses and provides a reservoir of divalent cations, which are otherwise scarce as a result of their complexation by hop acids. Some of the mechanisms involved in hop resistance overlap with mechanisms of pH resistance and ethanol tolerance and as a result enable beer spoilage by L. brevis. PMID:17021196

  18. Construction of a constitutively expressed homo-fermentative pathway in Lactobacillus brevis.

    PubMed

    Guo, Wei; He, Ronglin; Ma, Lijuan; Jia, Wendi; Li, Demao; Chen, Shulin

    2014-08-01

    Lactobacillus brevis is a promising lactic acid producing strain that simultaneously utilizes glucose and xylose from lignocellulosic hydrolysate without carbon catabolic repression and inhibition. The production of by-products acetic acid and ethanol has been the major drawback of this strain. Two genes, pfkA (fructose-6-phosphate kinase [PFK]) and fbaA (fructose-1,6-biphosphate aldolase [FBA]), that encode the key enzymes of the EMP/glycolytic pathway from Lactobacillus rhamnosus, were fused to the downstream of the strong promoter P32 and expressed in L. brevis s3f4 as a strategy to minimize the formation of by-products. By expressing the two enzymes, a homo-fermentative pathway for lactic acid production was constructed. The lactic acid yields achieved from glucose in the transformants were 1.12 and 1.16 mol/mol, which is higher than that of the native strain (0.74 mol/mol). However, the lactic acid yield from xylose in the transformants stayed the same as that of the native strain. Enzyme assay indicated that the activity of the foreign protein FBA in the transformants was much higher than that of the native strains, but was ten times lower than that in L. rhamnosus. This result was consistent with the metabolic flux analysis, which indicated that the conversion efficiency of the expressed PFK and FBA was somewhat low. Less than 20 % of the carbons accumulated in the form of fructose-6-phosphate were converted into glyceraldehyde-3-phosphate (GAP) by the expressed PFK and FBA. Metabolic flux analysis also indicated that the enzyme phosphoketolase (XPK) played an important role in splitting the carbon flow from the pentose phosphate pathway to the phosphoketolase pathway. This study suggested that the lactic acid yield of L. brevis could be improved by constructing a homo-fermentative pathway.

  19. Surface display of foreign epitopes on the Lactobacillus brevis S-layer.

    PubMed

    Avall-Jääskeläinen, Silja; Kylä-Nikkilä, Kari; Kahala, Minna; Miikkulainen-Lahti, Terhi; Palva, Airi

    2002-12-01

    So far, the inability to establish viable Lactobacillus surface layer (S-layer) null mutants has hampered the biotechnological applications of Lactobacillus S-layers. In this study, we demonstrate the utilization of Lactobacillus brevis S-layer subunits (SlpA) for the surface display of foreign antigenic epitopes. With an inducible expression system, L. brevis strains producing chimeric S-layers were obtained after testing of four insertion sites in the slpA gene for poliovirus epitope VP1, that comprises 10 amino acids. The epitope insertion site allowing the best surface expression was used for the construction of an integration vector carrying the gene region encoding the c-Myc epitopes from the human c-myc proto-oncogene, which is composed of 11 amino acids. A gene replacement system was optimized for L. brevis and used for the replacement of the wild-type slpA gene with the slpA-c-myc construct. A uniform S-layer, displaying on its surface the desired antigen in all of the S-layer protein subunits, was obtained. The success of the gene replacement and expression of the uniform SlpA-c-Myc recombinant S-layer was confirmed by PCR, Southern blotting MALDI-TOF mass spectrometry, whole-cell enzyme-linked immunosorbent assay, and immunofluorescence microscopy. Furthermore, the integrity of the recombinant S-layer was studied by electron microscopy, which indicated that the S-layer lattice structure was not affected by the presence of c-Myc epitopes. To our knowledge, this is the first successful expression of foreign epitopes in every S-layer subunit of a Lactobacillus S-layer while still maintaining the S-layer lattice structure.

  20. Purification and characterization of bacteriocin produced by strain of Lactobacillus brevis MTCC 7539.

    PubMed

    Gautam, Neha; Sharma, Nivedita

    2009-08-01

    Bacteriocin, an antimicrobial agent having potential for food biopreservation was purified from Lactobacillus brevis (a safe food-grade bacteria isolated from Vari Kandal, a traditional fermented food of Himachal Pradesh by adopting a novel repeated washing method. Its purity was confirmed by SDS-PAGE and Native-PAGE. The relative molecular mass of bacteriocin was 93.74 kD, while specific activity and recovery were 35.52 folds and 17.13%, respectively. It showed high thermal stability and was active over wide range of pH and exhibited sensitivity to trypsin.

  1. Cloning of aldB, which encodes alpha-acetolactate decarboxylase, an exoenzyme from Bacillus brevis.

    PubMed Central

    Diderichsen, B; Wedsted, U; Hedegaard, L; Jensen, B R; Sjøholm, C

    1990-01-01

    A gene for alpha-acetolactate decarboxylase (ALDC) was cloned from Bacillus brevis in Escherichia coli and in Bacillus subtilis. The 1.3-kilobase-pair nucleotide sequence of the gene, aldB, encoding ALDC and its flanking regions was determined. An open reading frame of 285 amino acids included a typical N-terminal signal peptide of 24 or 27 amino acids. A B. subtilis strain harboring the aldB gene on a recombinant plasmid processed and secreted ALDC. In contrast, a similar enzyme from Enterobacter aerogenes is intracellular. Images PMID:2198252

  2. Phytoplankton IF-FISH: Species-specific labeling of cellular proteins by immunofluorescence (IF) with simultaneous species identification by fluorescence immunohybridization (FISH).

    PubMed

    Meek, Megan E; Van Dolah, Frances M

    2016-05-01

    Phytoplankton rarely occur as unialgal populations. Therefore, to study species-specific protein expression, indicative of physiological status in natural populations, methods are needed that will both assay for a protein of interest and identify the species expressing it. Here we describe a protocol for IF-FISH, a dual labeling procedure using immunofluorescence (IF) labeling of a protein of interest followed by fluorescence in situ hybridization (FISH) to identify the species expressing that protein. The protocol was developed to monitor expression of the cell cycle marker proliferating cell nuclear antigen (PCNA) in the red tide dinoflagellate, Karenia brevis, using a large subunit (LSU) rRNA probe to identify K. brevis in a mixed population of morphologically similar Karenia species. We present this protocol as proof of concept that IF-FISH can be successfully applied to phytoplankton cells. This method is widely applicable for the analysis of single-cell protein expression of any protein of interest within phytoplankton communities.

  3. Xylan-mediated aggregation of Lactobacillus brevis and its relationship with the surface properties and mucin-mediated aggregation of the bacteria.

    PubMed

    Saito, Katsuichi; Nakamura, Toshihide; Kobayashi, Isao; Ohnishi-Kameyama, Mayumi; Ichinose, Hitomi; Kimura, Keitarou; Funane, Kazumi

    2014-01-01

    Some Lactobacillus brevis strains were found to aggregate upon the addition of xylan after screening for lactic acid bacteria that interact with plant materials. The S-layer proteins of cell surface varied among the strains. The strains that displayed xylan-mediated aggregation retained its ability even after the removal of S-layer proteins. L. brevis had negative zeta potentials. A correlation between the strength of aggregation and zeta potential was not observed. However, partial removal of S-layer proteins resulted in decreases in the electric potential and aggregation ability of some strains. Therefore, xylan-mediated aggregation of L. brevis was considered to be caused by an electrostatic effect between the cells and xylan. L. brevis also aggregated in the presence of mucin, and the strengths of aggregation among the strains were similar to that induced by xylan. Thus, xylan- and mucin-mediated L. brevis aggregation was supposed to be caused by a similar mechanism.

  4. Allosteric regulation of the glucose:H+ symporter of Lactobacillus brevis: cooperative binding of glucose and HPr(ser-P).

    PubMed Central

    Ye, J J; Saier, M H

    1995-01-01

    Lactobacillus brevis transports glucose and the nonmetabolizable glucose analog 2-deoxyglucose via a proton symport mechanism that is allosterically inhibited by the seryl-phosphorylated derivative of HPr, the small phosphocarrier protein of the phosphotransferase system. We have demonstrate that S46DHPr, a mutant analog of HPr which conformationally resembles HPr(ser-P) but not free HPr, specifically binds to membranes derived from glucose-grown L. brevis cells if and only if a substrate of the glucose permease is also present. PMID:7896720

  5. Brevis plant1, a putative inositol polyphosphate 5-phosphatase, is required for internode elongation in maize.

    PubMed

    Avila, Luis M; Cerrudo, Diego; Swanton, Clarence; Lukens, Lewis

    2016-03-01

    In maize (Zea mays L.), as in other grass species, stem elongation occurs during growth and most noticeably upon the transition to flowering. Genes that reduce stem elongation have been important to reduce stem breakage, or lodging. Stem elongation has been mediated by dwarf and brachytic/brevis plant mutants that affect giberellic acid and auxin pathways, respectively. Maize brevis plant1 (bv1) mutants, first identified over 80 years ago, strongly resemble brachytic2 mutants that have shortened internodes, short internode cells, and are deficient in auxin transport. Here, we characterized two novel bv1 maize mutants. We found that an inositol polyphosphate 5-phosphatase orthologue of the rice gene dwarf50 was the molecular basis for the bv1 phenotype, implicating auxin-mediated inositol polyphosphate and/or phosphoinositide signalling in stem elongation. We suggest that auxin-mediated internode elongation involves processes that also contribute to stem gravitropism. Genes misregulated in bv1 mutants included genes important for cell wall synthesis, transmembrane transport, and cytoskeletal function. Mutant and wild-type plants were indistinguishable early in development, responded similarly to changes in light quality, had unaltered flowering times, and had normal flower development. These attributes suggest that breeding could utilize bv1 alleles to increase crop grain yields.

  6. Physiology-Oriented Engineering Strategy to Improve Gamma-Aminobutyrate Production in Lactobacillus brevis.

    PubMed

    Lyu, Chang-Jiang; Zhao, Wei-Rui; Hu, Sheng; Huang, Jun; Lu, Tao; Jin, Zhi-Hua; Mei, Le-He; Yao, Shan-Jing

    2017-02-01

    Gamma-aminobutyrate (GABA) is an important chemical in the pharmaceutical field. GABA-producing lactic acid bacteria (LAB) offer the opportunity of developing this health-oriented product. In this study, the gadA, gadB, gadC, gadCB, and gadCA gene segments of Lactobacillus brevis were cloned into pMG36e, and strain Lb. brevis/pMG36e-gadA was selected for thorough characterization in terms of GABA production after analysis of GAD activities. Subsequently, a physiology-oriented engineering strategy was adopted to construct an FoF1-ATPase deficient strain NRA6 with higher GAD activity. As expected, strain NRA6 could produce GABA at a concentration of 43.65 g/L with a 98.42% GABA conversion rate in GYP fermentation medium, which is 1.22-fold higher than that obtained by the wild-type strain in the same condition. This work demonstrates how the acid stress response mechanisms of LAB can be employed to develop cell factories with improved production efficiency and contributes to research into the development of the physiology-oriented engineering.

  7. In situ examination of Lactobacillus brevis after exposure to an oxidizing disinfectant.

    PubMed

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2014-01-01

    Beer is a hostile environment for most microorganisms, but some lactic acid bacteria can grow in this environment. This is primarily because these organisms have developed the ability to grow in the presence of hops. It has been speculated that hop resistance is inversely correlated to resistance against oxidation, and this would have great impact on the use of various disinfectants in the brewing industry. In this study, we cultivated bacteria under aerobic and anaerobic conditions, and then investigated the in situ outgrowth of individual cells into microcolonies on de Man Rogosa Sharpe (MRS) agar after exposure to the oxidizing agent peracetic acid (PAA). An automated microscope stage allowed us to analyse a much larger number of cells over extended periods of incubation. After PAA treatment, the lag time increased markedly, and extensive variation in morphology, μmax as well as stress resistance was observed between and within the tested Lactobacillus brevis strains. The results suggest that aerobic cultivation increased the oxidative stress tolerance in Lactobacillus brevis. The results also show that dead cells are randomly distributed in a microcolony and the majority of non-growing individual cells do not stain with a membrane impermanent dye (Propidium iodide), which indicates that PAA may not destroy the plasma membrane. In conclusion, the developed microscopic analysis of individual cells on MRS agar can provides faster results and more details of cell physiology compared to the traditional CFU method.

  8. In situ examination of Lactobacillus brevis after exposure to an oxidizing disinfectant

    PubMed Central

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2014-01-01

    Beer is a hostile environment for most microorganisms, but some lactic acid bacteria can grow in this environment. This is primarily because these organisms have developed the ability to grow in the presence of hops. It has been speculated that hop resistance is inversely correlated to resistance against oxidation, and this would have great impact on the use of various disinfectants in the brewing industry. In this study, we cultivated bacteria under aerobic and anaerobic conditions, and then investigated the in situ outgrowth of individual cells into microcolonies on de Man Rogosa Sharpe (MRS) agar after exposure to the oxidizing agent peracetic acid (PAA). An automated microscope stage allowed us to analyse a much larger number of cells over extended periods of incubation. After PAA treatment, the lag time increased markedly, and extensive variation in morphology, μmax as well as stress resistance was observed between and within the tested Lactobacillus brevis strains. The results suggest that aerobic cultivation increased the oxidative stress tolerance in Lactobacillus brevis. The results also show that dead cells are randomly distributed in a microcolony and the majority of non-growing individual cells do not stain with a membrane impermanent dye (Propidium iodide), which indicates that PAA may not destroy the plasma membrane. In conclusion, the developed microscopic analysis of individual cells on MRS agar can provides faster results and more details of cell physiology compared to the traditional CFU method. PMID:25505451

  9. Mycelial carton galleries of Azteca brevis (Formicidae) as a multi-species network

    PubMed Central

    Mayer, Veronika E.; Voglmayr, Hermann

    2009-01-01

    Apart from growing fungi for nutrition, as seen in the New World Attini, ants cultivate fungi for reinforcement of the walls of their nests or tunnel-shaped runway galleries. These fungi are grown on organic material such as bark, epiphylls or trichomes, and form stable ‘carton structures’. In this study, the carton of the runway galleries built by Azteca brevis (Formicidae, Dolichoderinae) on branches of Tetrathylacium macrophyllum (Flacourtiaceae) is investigated. For the first time, molecular tools are used to address the biodiversity and phylogenetic affinities of fungi involved in tropical ant carton architecture, a previously neglected ant–fungus mutualism. The A. brevis carton involves a complex association of several fungi. All the isolated fungi were unequivocally placed within the Chaetothyriales by DNA sequence data. Whereas five types of fungal hyphae were morphologically distinguishable, our DNA data showed that more species are involved, applying a phylogenetic species concept based on DNA phylogenies and hyphal morphology. In contrast to the New World Attini with their many-to-one (different ant species—one fungal cultivar) pattern, and temperate Lasius with a one-to-two (one ant species—two mutualists) or many-to-one (different ant species share the same mutualist) system, the A. brevis–fungi association is a one-to-many multi-species network. Vertical fungus transmission has not yet been found, indicating that the A. brevis–fungi interaction is rather generalized. PMID:19556257

  10. Brevis plant1, a putative inositol polyphosphate 5-phosphatase, is required for internode elongation in maize

    PubMed Central

    Avila, Luis M.; Cerrudo, Diego; Swanton, Clarence

    2016-01-01

    In maize (Zea mays L.), as in other grass species, stem elongation occurs during growth and most noticeably upon the transition to flowering. Genes that reduce stem elongation have been important to reduce stem breakage, or lodging. Stem elongation has been mediated by dwarf and brachytic/brevis plant mutants that affect giberellic acid and auxin pathways, respectively. Maize brevis plant1 (bv1) mutants, first identified over 80 years ago, strongly resemble brachytic2 mutants that have shortened internodes, short internode cells, and are deficient in auxin transport. Here, we characterized two novel bv1 maize mutants. We found that an inositol polyphosphate 5-phosphatase orthologue of the rice gene dwarf50 was the molecular basis for the bv1 phenotype, implicating auxin-mediated inositol polyphosphate and/or phosphoinositide signalling in stem elongation. We suggest that auxin-mediated internode elongation involves processes that also contribute to stem gravitropism. Genes misregulated in bv1 mutants included genes important for cell wall synthesis, transmembrane transport, and cytoskeletal function. Mutant and wild-type plants were indistinguishable early in development, responded similarly to changes in light quality, had unaltered flowering times, and had normal flower development. These attributes suggest that breeding could utilize bv1 alleles to increase crop grain yields. PMID:26767748

  11. Effect of Lactobacillus brevis KB290 on the cell-mediated cytotoxic activity of mouse splenocytes: a DNA microarray analysis.

    PubMed

    Fukui, Yuichiro; Sasaki, Erika; Fuke, Nobuo; Nakai, Yuji; Ishijima, Tomoko; Abe, Keiko; Yajima, Nobuhiro

    2013-11-14

    Lactic acid bacteria confer a variety of health benefits. Here, we investigate the mechanisms by which Lactobacillus brevis KB290 (KB290) enhances cell-mediated cytotoxic activity. Female BALB/c mice aged 9 weeks were fed a diet containing KB290 (3 × 10(9) colony-forming units/g) or starch for 1 d. The resulting cytotoxic activity of splenocytes against YAC-1 cells was measured using flow cytometry and analysed for gene expression using DNA microarray technology. KB290 enhanced the cell-mediated cytotoxic activity of splenocytes. DNA microarray analysis identified 327 up-regulated and 347 down-regulated genes that characterised the KB290 diet group. The up-regulated genes were significantly enriched in Gene Ontology terms related to immunity, and, especially, a positive regulation of T-cell-mediated cytotoxicity existed among these terms. Almost all the genes included in the term encoded major histocompatibility complex (MHC) class I molecules involved in the presentation of antigen to CD8(+) cytotoxic T cells. Marco and Signr1 specific to marginal zone macrophages (MZM), antigen-presenting cells, were also up-regulated. Flow cytometric analysis confirmed that the proportion of MZM was significantly increased by KB290 ingestion. Additionally, the over-represented Kyoto Encyclopedia of Genes and Genomes pathways among the up-regulated genes were those for natural killer (NK) cell-mediated cytotoxicity and antigen processing and presentation. The results for the selected genes associated with NK cells and CD8(+) cytotoxic T cells were confirmed by quantitative RT-PCR. These results suggest that enhanced cytotoxic activity could be caused by the activation of NK cells and/or of CD8(+) cytotoxic T cells stimulated via MHC class I presentation.

  12. Sequential gene expression profiling in the mouse spleen during 14 d feeding with Lactobacillus brevis KB290.

    PubMed

    Fukui, Yuichiro; Sasaki, Erika; Fuke, Nobuo; Nakai, Yuji; Ishijima, Tomoko; Abe, Keiko; Yajima, Nobuhiro

    2014-06-14

    Some lactic acid bacteria play an important role in the immune system with potential benefits to the host. However, detailed mechanisms of immune modulation exerted by probiotics remain to be clarified. Since immune response changes in a time-related manner in some cases, we monitored changes in mRNA levels in the spleen of mice during 14 d feeding with Lactobacillus brevis KB290 (KB290). Female BALB/c mice, aged 9 weeks, commenced a diet containing KB290 (3 × 109 colony-forming units/g) or starch for a period of 1, 4, 7 or 14 d. Cytotoxic activity of the resulting splenocytes against YAC-1 cells was measured using flow cytometry. The activity was found to be significantly higher in the treated group on days 1 and 7. The highest activity appeared on day 4, but was not statistically significantly different. Gene expression profiles were analysed using DNA microarray. Gene Ontology (GO) terms related to the immune process were significantly enriched in the up-regulated gene set on days 1, 4 and 7, and GO terms related to the cellular process were enriched in the down-regulated gene set on days 4 and 7. Although the up-regulated genes involved in antigen processing and presentation for stimulation of CD8+ cytotoxic T cells were not observed on day 14, some genes involved in T-cell and natural killer cell activation remained up-regulated until day 14. For the majority of the genes tested, RT-PCR analysis was used to verify the results obtained from the DNA microarray analysis. The sequential gene expression profiling reflected changes in cytotoxic activity during KB290 feeding.

  13. Evidence of horizontal transfer as origin of strain to strain variation of the tyramine production trait in Lactobacillus brevis.

    PubMed

    Coton, Emmanuel; Coton, Monika

    2009-02-01

    Lactobacillus brevis strains with the ability to decarboxylate tyrosine to tyramine have been described and the involvement of several genes constituting a tyrdc operon at the chromosomal level has been demonstrated in this species. In this study, the existence of Lb. brevis strains unable to form tyramine was observed. In order to evaluate if the tyramine-producing ability was strain-dependent or if it could be correlated to the existence of a new species or subspecies, different isolates were analysed. Analysis by M13-RAPD and sequencing of 16S rDNA, 16S-23S ISR and house-keeping gene recA confirmed that all the isolates belonged to the Lb. brevis species. Analysis of the TyrDC pathway encoding operon region in representative strains indicated the existence of a polymorphism. The genetic differences observed showed that the tyrosine decarboxylating ability is not a Lb. brevis species trait but that it is strain-dependent within this species and suggest that the genes encoding the tyramine-producing pathway constitute a genomic island.

  14. Open-book Splitting of a Distally Based Peroneus Brevis Muscle Flap to Cover Large Leg and Ankle Defects

    PubMed Central

    2015-01-01

    Abstract Background: Large soft-tissue defects in the lower leg and ankle are a major problem for plastic surgeons. Many local flaps that are either proximally or distally based have been previously described to cover small defects. Larger defects may require a distant flap that is either pedicled or free. The peroneus brevis muscle flap is a well-known distally based safe flap that is used to cover a small defect. Methods: Ten distally based peroneus brevis muscle flaps were elevated in 10 patients (8 males and 2 females) with major lower third leg and ankle defects that were 6–12 cm in length and 6–10 cm in width, with open-book splitting of the proximal portion of the muscle to cover these large defects. Results: Flap survival was excellent, and partial skin graft loss in two cases healed with dressing. The average flap length was 10 cm, ranging between 6 and 12 cm. The average flap width was 8 cm, ranging between 6 and 10 cm. The donor site also healed uneventful. Conclusions: Open-book splitting of the distally based peroneus brevis muscle flap is ideally suited for moderate to large defects in the distal third of the lower leg and ankle. This modification of the distally based peroneus brevis muscle flap offers a convincing alternative for covering large defects of up to 12 × 10 cm in the distal leg and ankle region. PMID:26893997

  15. Draft Genome Sequences of Lactobacillus plantarum Strain 90sk and Lactobacillus brevis Strain 15f: Focusing on Neurotransmitter Genes

    PubMed Central

    Yunes, Roman A.; Klimina, Ksenia M.; Emelyanov, Kirill V.; Zakharevich, Natalia V.; Poluektova, Elena U.

    2015-01-01

    The genomes of Lactobacillus plantarum strain 90sk and Lactobacillus brevis strain 15f were isolated from human intestinal microbiota. Both strains synthesize gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter. Detailed genome analyses will help to understand the role of GABA in the interaction of bacteria with human intestinal cells. PMID:25883284

  16. Draft Genome Sequences of Lactobacillus plantarum Strain 90sk and Lactobacillus brevis Strain 15f: Focusing on Neurotransmitter Genes.

    PubMed

    Yunes, Roman A; Klimina, Ksenia M; Emelyanov, Kirill V; Zakharevich, Natalia V; Poluektova, Elena U; Danilenko, Valery N

    2015-04-16

    The genomes of Lactobacillus plantarum strain 90sk and Lactobacillus brevis strain 15f were isolated from human intestinal microbiota. Both strains synthesize gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter. Detailed genome analyses will help to understand the role of GABA in the interaction of bacteria with human intestinal cells.

  17. Spontaneous rupture of the extensor carpi radialis brevis in a 51-year-old man: case report.

    PubMed

    Huffaker, Stephen J; Christoforou, Dimitrios C; Jupiter, Jesse B

    2012-06-01

    Dorsal hand osteophytes are common findings in the general population, frequently presenting with dorsal pain and treated with surgical excision. We report the spontaneous rupture of the extensor carpi radialis brevis in association with a previously asymptomatic dorsal scaphoid spur. Following conservative management, surgical excision of dorsal hand osteophytes should be considered for both resolution of pain and prevention of attritional tendon rupture.

  18. HPLC Analysis and Cytotoxicity of n-Butanol Extract from Glyphaea brevis Roots Against C6 Glioma Cells

    PubMed Central

    Konan, Koffi Marcel; Mamyrbekova-Bekro, Janat Akhanovna; Bakalara, Norbert; Virieux, David; Pirat, Jean-Luc; Bekro, Yves-Alain

    2014-01-01

    The n-butanol extract of the roots of Glyphaea brevis was analysed. HPLC analysis suggested the presence of phenolic compounds like protocatechuic acid (PCA). The extract showed moderate cytotoxic activity against C6 glioma cells (EC50 > 1 mg/ml). PMID:24634849

  19. Probiotic and antioxidant properties of selenium-enriched Lactobacillus brevis LSe isolated from an Iranian traditional dairy product.

    PubMed

    Shakibaie, Mojtaba; Mohammadi-Khorsand, Tayebe; Adeli-Sardou, Mahboubeh; Jafari, Mandana; Amirpour-Rostami, Sahar; Ameri, Alieh; Forootanfar, Hamid

    2017-03-01

    The present study was designed to isolate a highly selenium-tolerant lactobacillus strain from an Iranian traditional dairy product named as Spar. Different criteria such as tolerance to the low pH, simulated gastric juice (SGJ), simulated intestinal juice (SIJ) and bile salts tolerance as well as Caco-2 cell adhesion assay were examined to evaluate the probiotic potentials of the selected isolate. Furthermore, the antioxidant properties of the isolate cultivated in medium containing and free of SeO3(2-) ions were evaluated using DPPH scavenging and reducing power assays. The isolate was identified using conventional identification and 16S rDNA gene sequencing methods as Lactobacillus brevis LSe. The obtained results showed that the isolate was able to tolerate high concentration of sodium selenite (3.16mM). By decreasing the pH of the SGJ from 6 to 3, the survival percent of L. brevis LSe was not significantly changed over the time (p>0.05). In addition, the survival percent of the isolate in the SIJ (pH 6 and pH 8) was not statistically altered after 3h, 6h and 24h of incubation (p>0.05). In the presence of bile salts (0.3% and 0.6%) the survival rate of L. brevis LSe was not significantly decreased (p>0.05).L. brevis LSe also demonstrated the satisfactory ability to adhere to Caco-2 cells which were similar to that of the reference strain L. plantarum. The obtained results of antioxidant evaluation showed that L. brevis LSe containing elemental Se exhibited significantly higher radical scavenging ability (36.5±1.31%) and reducing power (OD700, 0.14) than L. brevis LSe cultured in selenite-free medium (p<0.05). To sum up, further investigations should be conducted to merit the probable potential health benefit of Se-enriched L. brevis LSe and its application as Se-containing supplements or fermented foods.

  20. The role of hydrographic parameters, measured from a ship of opportunity, in bloom formation of Karenia mikimotoi in the English Channel

    NASA Astrophysics Data System (ADS)

    Hartman, S. E.; Hartman, M. C.; Hydes, D. J.; Smythe-Wright, D.; Gohin, F.; Lazure, P.

    2014-12-01

    Unusually high chlorophyll values (~ 14 mg Chl m- 3 at 5 m depth), recorded on a ship of opportunity (SOO) in July 2010, indicated the occurrence of a potential Harmful Algal Bloom (HAB) in the Western approaches of the English Channel. This bloom, located at 49.7°N, 3.2°W was observed via complementary datasets. These included data from samples collected for microscopic phytoplankton identification, information from satellite maps to follow geographical bloom development and in situ data to identify hydrographic factors related to bloom initiation. The relationships between chlorophyll-fluorescence, temperature, salinity and wind speed were examined. The intense summer bloom predominantly consisted of the dinoflagellate Karenia mikimotoi and followed an increase in sea surface temperature (to 18.5 °C). A mid-channel bloom of this magnitude along the SOO route was last seen in 2003. In both years the peak biomass was associated with K. mikimotoi blooms, which occurred at the same location and coincided with the least saline, warmest water and lowest wind speeds. This study demonstrates that ships of opportunity are a useful tool to identify and track HAB events through continuous in situ measurements and for the frequent sampling opportunities that they provide.

  1. Lactic acid production from biomass-derived sugars via co-fermentation of Lactobacillus brevis and Lactobacillus plantarum.

    PubMed

    Zhang, Yixing; Vadlani, Praveen V

    2015-06-01

    Lignocellulosic biomass is an attractive alternative resource for producing chemicals and fuels. Xylose is the dominating sugar after hydrolysis of hemicellulose in the biomass, but most microorganisms either cannot ferment xylose or have a hierarchical sugar utilization pattern in which glucose is consumed first. To overcome this barrier, Lactobacillus brevis ATCC 367 was selected to produce lactic acid. This strain possesses a relaxed carbon catabolite repression mechanism that can use glucose and xylose simultaneously; however, lactic acid yield was only 0.52 g g(-1) from a mixture of glucose and xylose, and 5.1 g L(-1) of acetic acid and 8.3 g L(-1) of ethanol were also formed during production of lactic acid. The yield was significantly increased and ethanol production was significantly reduced if L. brevis was co-cultivated with Lactobacillus plantarum ATCC 21028. L. plantarum outcompeted L. brevis in glucose consumption, meaning that L. brevis was focused on converting xylose to lactic acid and the by-product, ethanol, was reduced due to less NADH generated in the fermentation system. Sequential co-fermentation of L. brevis and L. plantarum increased lactic acid yield to 0.80 g g(-1) from poplar hydrolyzate and increased yield to 0.78 g lactic acid per g of biomass from alkali-treated corn stover with minimum by-product formation. Efficient utilization of both cellulose and hemicellulose components of the biomass will improve overall lactic acid production and enable an economical process to produce biodegradable plastics.

  2. gadA gene locus in Lactobacillus brevis NCL912 and its expression during fed-batch fermentation.

    PubMed

    Li, Haixing; Li, Wenming; Liu, Xiaohua; Cao, Yusheng

    2013-12-01

    Normally, Lactobacillus brevis has two glutamate decarboxylase (GAD) genes; gadA and gadB. Using PCR, we cloned the gadA gene from L. brevis strain NCL912, a high yield strain for the production of gamma-aminobutyric acid (GABA). However, despite using 61 different primer pairs, including degenerate primers from conserved regions, we were unable to use PCR to clone gadB from the NCL912 strain. Furthermore, we could not clone it by genomic walking over 3000 bp downstream of the aldo-keto reductase gene, a single-copy gene that is located 1003 bp upstream of gadB in L. brevis ATCC367. Altogether, the data suggest that L. brevis NCL912 does not contain a gadB gene. By genomic walking, we cloned regions upstream and downstream of the gadA gene to obtain a 4615 bp DNA fragment that included the complete gadA locus. The locus contained the GAD gene (gadA) and the glutamate:GABA antiporter gene (gadC), which appear to be transcribed in an operon (gadCA), and a transcriptional regulator (gadR) of gadCA. During whole fed-batch fermentation, the expression of gadR, gadC and gadA was synchronized and correlated well with GABA production. The gadA locus we cloned from NCL912 has reduced homology compared with gadA loci of other L. brevis strains, and these differences might explain the ability of NCL912 to produce higher levels of GABA in culture.

  3. Strain-specific probiotics properties of Lactobacillus fermentum, Lactobacillus plantarum and Lactobacillus brevis isolates from Brazilian food products.

    PubMed

    Ramos, Cíntia Lacerda; Thorsen, Line; Schwan, Rosane Freitas; Jespersen, Lene

    2013-10-01

    A total of 234 LAB isolates from Brazilian food products were initially screened for their ability to survive at pH 2.0. Fifty one of the isolates survived and were selected. They were characterized by phenotypic methods, rep-PCR and identified using 16S rRNA gene sequencing as Lactobacillus fermentum (34 isolates), Lactobacillus plantarum (10) and Lactobacillus brevis (7). Based on being either highly tolerant to bile, showing an ability for auto-aggregation and/or hydrophobic properties, one L. fermentum (CH58), three L. plantarum (CH3, CH41 and SAU96) and two L. brevis (SAU105 and FFC199) were selected. The highest co-aggregation ability with Escherichia coli was observed to L. plantarum CH41. L. brevis SAU105 and FFC199 and L. fermentum CH58 exhibited antagonistic activity towards the pathogens Listeria monocytogenes and Staphylococcus aureus. L. plantarum CH3 and CH41 and L. brevis FFC199 showed adhesion ability to Caco-2 cells (1.6, 1.1 and 0.9%, respectively) similar to the commercial probiotic, Lactobacillus rhamnosus GG (1.5%). They were able to increase the transepithelial electrical resistance (TEER) of Caco-2 cells over 24 h (p < 0.05). The present work showed that the probiotic characteristics were strain-specific and that the isolates L. plantarum CH3 and CH41 (cocoa) and L. brevis FFC199 (cauim) exhibited potential probiotics properties.

  4. Effects of Brevibacillus brevis FJAT-1501-BPA on growth performance, faecal microflora, faecal enzyme activities and blood parameters of weaned piglets.

    PubMed

    Che, Jianmei; Ye, Shaowen; Liu, Bo; Deng, Yuanyuan; Chen, Qianqian; Ge, Cibin; Liu, Guohong; Wang, Jieping

    2016-12-01

    A feeding expriment was performed to investigate the effects of dietary supplementation with Brevibacillus brevis FJAT-1501-BPA fermentation on the growth performance, faecal microflora, faecal enzyme activities and blood parameters of weaned piglets. A total of 150 weaned piglets were randomly assigned to different treatments groups, which were fed the same basic diet supplemented with 10, 1, 0.1, 0.01 and 0 % B. brevis FJAT-1501-BPA fermentation. The results showed that a diet supplemented with 10 % B. brevis FJAT-1501-BPA fermentation could significantly increase the final body weight (P < 0.05) and decrease feed to gain ratio, which was 37.1 % lower than that of the control group. The addition of B. brevis FJAT-1501-BPA exhibited a trend of reducing the contents of the Escherichia coli, Lactobacillus and Salmonella compared with the control. During the 35 day experimental period, cellulase and protease activities were significantly increased by the dietary inclusion of the B. brevis FJAT-1501-BPA fermentation (P < 0.05). The cellulase activity for piglets fed diet containing 1 % B. brevis FJAT-1501-BPA fermentation, 21.8 U/g, was highest among the different treatments. The protease activity for piglets fed diet containing 10 % B. brevis FJAT-1501-BPA fermentation, 50.4 U/g, was highest among the different treatments. The amylase and hemicellulase activities for piglets fed diet containing 10 % B. brevis FJAT-1501-BPA fermentation were significantly higher than those on the control diet and other treatments (P < 0.05). Moreover, usage of feed dietary supplementation with B. brevis FJAT-1501-BPA had positive effects on levels of enzymes and minerals in blood. The alkaline phosphatase, alanine aminotransferase, Fe and Mg concentrations for weaned piglets fed diet containing B. brevis FJAT-1501-BPA fermentation were significantly higher than for those on the control diet (P < 0.05). Furthermore, concentration of IgG in serum was higher in weaned

  5. Production optimization of invertase by Lactobacillus brevis Mm-6 and its immobilization on alginate beads.

    PubMed

    Awad, Ghada E A; Amer, Hassan; El-Gammal, Eman W; Helmy, Wafaa A; Esawy, Mona A; Elnashar, Magdy M M

    2013-04-02

    A sequential optimization strategy, based on statistical experimental designs, was employed to enhance the production of invertase by Lactobacillus brevis Mm-6 isolated from breast milk. First, a 2-level Plackett-Burman design was applied to screen the bioprocess parameters that significantly influence the invertase production. The second optimization step was performed using fractional factorial design in order to optimize the amounts of variables have the highest positive significant effect on the invertase production. A maximal enzyme activity of 1399U/ml was more than five folds the activity obtained using the basal medium. Invertase was immobilized onto grafted alginate beads to improve the enzyme's stability. Immobilization process increased the operational temperature from 30 to 60°C compared to the free enzyme. The reusability test proved the durability of the grafted alginate beads for 15 cycles with retention of 100% of the immobilized enzyme activity to be more convenient for industrial uses.

  6. A protein disulfide isomerase gene fusion expression system that increases the extracellular productivity of Bacillus brevis.

    PubMed

    Kajino, T; Ohto, C; Muramatsu, M; Obata, S; Udaka, S; Yamada, Y; Takahashi, H

    2000-02-01

    We have developed a versatile Bacillus brevis expression and secretion system based on the use of fungal protein disulfide isomerase (PDI) as a gene fusion partner. Fusion with PDI increased the extracellular production of heterologous proteins (light chain of immunoglobulin G, 8-fold; geranylgeranyl pyrophosphate synthase, 12-fold). Linkage to PDI prevented the aggregation of the secreted proteins, resulting in high-level accumulation of fusion proteins in soluble and biologically active forms. We also show that the disulfide isomerase activity of PDI in a fusion protein is responsible for the suppression of the aggregation of the protein with intradisulfide, whereas aggregation of the protein without intradisulfide was prevented even when the protein was fused to a mutant PDI whose two active sites were disrupted, suggesting that another PDI function, such as chaperone-like activity, synergistically prevented the aggregation of heterologous proteins in the PDI fusion expression system.

  7. Surgical Management of Symptomatic Extensor Digitorum Brevis Manus: A Proposed Algorithm for Treatment.

    PubMed

    Waterman, Brian R; Dunn, John C; Kusnezov, Nicholas; Romano, David; Pirela-Cruz, Miguel A

    2015-10-01

    First described in 1734, the extensor digitorum brevis manus (EDBM) is an anomalous extensor muscle found in the dorsum of the wrist and hand. Extensor muscle variants of the hand are not uncommon, and EDBM has an estimated reported incidence of approximately 2%. Although few extensor muscle variants become clinically significant, there is a paucity of literature discussing these anatomic variants, with most reports arising from cadaveric studies or isolated case series. Similarly, there are few established indications for surgical treatment of EDBM. In this case report, we describe the successful treatment of a young patient with persistently symptomatic anomalous extensor tendon with surgical excision and propose an algorithm for management after failure of conservative measures.

  8. Growth Response of Lactobacillus brevis to Aeration and Organic Catalysts1

    PubMed Central

    Stamer, J. R.; Stoyla, B. O.

    1967-01-01

    Under stationary and anaerobic conditions, greater cell yields of Lactobacillus brevis were obtained from autoclaved than from filter-sterilized glucose media. Fructose, tentatively identified as a product generated by the heating process, served as an excellent catalyst for inducing growth. The addition of micromolar quantities of pentoses or potential pentose precursors to the filter-sterilized medium was equally effective in stimulating growth. These organic catalysts were not essential for growth under aerobic conditions. Upon agitation, similar cell yields were obtained from the autoclaved and filter-sterilized media. The micromolar quantities of lactic acid produced per micromole of carbohydrate fermented appeared to be similar under aerobic and static conditions of incubation. The final concentration of acetic acid increased as the result of agitation. This increase in volatile acidity was accompanied by a significant decrease in ethyl alcohol production. The cell yield was increased nearly 50% under aerobic conditions. PMID:16349721

  9. Lactobacillus brevis G101 inhibits the absorption of monosodium glutamate in mice.

    PubMed

    Jang, Se-Eun; Han, Myung Joo; Kim, Se-Young; Kim, Dong-Hyun

    2014-11-28

    To evaluate the effect of Lactobacillus brevis G-101 on absorption of monosodium glutamate (MSG), we orally administered MSG with or without G-101 in mice and measured the maximum concentration (Cmax) and blood concentration curve (AUC) of MSG and γ- aminobutyric acid (GABA). Oral administration of G-101 (1 × 10(9) CFU/mouse) potently inhibited Cmax and AUC of MSG by 97.8% and 94.3%, respectively (p < 0.05), but increased those of GABA by 32.1% and 67.7%, respectively (p < 0.05). G-101 inhibited the absorption of MSG. These results suggest that G-101 may reduce the side effect of MSG by inhibiting the absorption of MSG.

  10. Microbial ketonization of ginsenosides F1 and C-K by Lactobacillus brevis.

    PubMed

    Jin, Yan; Jung, Sun Young; Kim, Yeon-Ju; Lee, Dae-Young; Min, Jin-Woo; Wang, Chao; Yang, Deok-Chun

    2014-12-01

    Ginsenosides are the major pharmacological components in ginseng. We isolated lactic acid bacteria from Kimchi to identify microbial modifications of ginsenosides. Phylogenetic analysis of 16S rRNA gene sequences indicated that the strain DCY65-1 belongs to the genus Lactobacillus and is most closely related to Lactobacillus brevis. On the basis of TLC and HPLC analysis, we found two metabolic pathways: F1 → 6α,12β-dihydroxydammar-3-one-20(S)-O-β-D-glucopyranoside and C-K → 12β-hydroxydammar-3-one-20(S)-O-β-D-glucopyranoside. These results suggest that strain DCY65-1 is capable of potent ketonic decarboxylation, ketonizing the hydroxyl group at C-3. The F1 metabolite had a more potent inhibitory effect on mushroom tyrosinase than did the substrate. Therefore, the F1 and C-K derivatives may be more pharmacologically active compounds, which should be further characterized.

  11. Tight controlled expression and secretion of Lactobacillus brevis SlpA in Lactococcus lactis.

    PubMed

    Hollmann, Axel; Saviello, Mariano; Delfederico, Lucrecia; Saraiva, Tessália Diniz Luerce; Barh, Debmalya; Jain, Neha; Tiwari, Sandeep; Chandra, Sudha; Gupta, Krishnakant; Zambare, Vasudeo; Kumar, Anil; Christopher, Lew; Misra, Amarendra Narayan; Kumavath, Ranjith N; Azevedo, Vasco; Semorile, Liliana; Miyoshi, Anderson

    2012-07-01

    Prokaryotes commonly present outer cell wall structures composed of a crystalline array of proteinaceous subunits, known as surface layers (S-layers). The ORF encoding the S-layer protein (SlpA) of Lactobacillus brevis was cloned into Lactococcus lactis under the transcriptional control of the xylose-inducible expression system (XIES). SlpA was secreted into the extracellular medium, as determined by immunoblotting, and assays on the kinetics of SlpA production revealed that repression of the system with glucose did not require the depletion of xylose from the medium that allows transitory ORF expression. The successful use of XIES to express S-layer proteins in the versatile and generally recognized as safe species L. lactis opens new possibilities for an efficient production and isolation of SlpA S-layer protein for its various applications in biotechnology and importantly as an antigen-carrying vehicle.

  12. Role of Plasmids in Lactobacillus brevis BSO 464 Hop Tolerance and Beer Spoilage

    PubMed Central

    Bergsveinson, Jordyn; Baecker, Nina; Pittet, Vanessa

    2014-01-01

    Specific isolates of lactic acid bacteria (LAB) can grow in the harsh beer environment, thus posing a threat to brew quality and the economic success of breweries worldwide. Plasmid-localized genes, such as horA, horC, and hitA, have been suggested to confer hop tolerance, a trait required for LAB survival in beer. The presence and expression of these genes among LAB, however, do not universally correlate with the ability to grow in beer. Genome sequencing of the virulent beer spoilage organism Lactobacillus brevis BSO 464 revealed the presence of eight plasmids, with plasmids 1, 2, and 3 containing horA, horC, and hitA, respectively. To investigate the roles that these and the other five plasmids play in L. brevis BSO 464 growth in beer, plasmid curing with novobiocin was used to derive 10 plasmid variants. Multiplex PCRs were utilized to determine the presence or absence of each plasmid, and how plasmid loss affected hop tolerance and growth in degassed (noncarbonated) beer was assessed. Loss of three of the eight plasmids was found to affect hop tolerance and growth in beer. Loss of plasmid 2 (horC and 28 other genes) had the most dramatic effect, with loss of plasmid 4 (120 genes) and plasmid 8 (47 genes) having significant, but smaller, impacts. These results support the contention that genes on mobile genetic elements are essential for bacterial growth in beer and that beer spoilage ability is not dependent solely on the three previously described hop tolerance genes or on the chromosome of a beer spoilage LAB isolate. PMID:25501474

  13. Role of plasmids in Lactobacillus brevis BSO 464 hop tolerance and beer spoilage.

    PubMed

    Bergsveinson, Jordyn; Baecker, Nina; Pittet, Vanessa; Ziola, Barry

    2015-02-01

    Specific isolates of lactic acid bacteria (LAB) can grow in the harsh beer environment, thus posing a threat to brew quality and the economic success of breweries worldwide. Plasmid-localized genes, such as horA, horC, and hitA, have been suggested to confer hop tolerance, a trait required for LAB survival in beer. The presence and expression of these genes among LAB, however, do not universally correlate with the ability to grow in beer. Genome sequencing of the virulent beer spoilage organism Lactobacillus brevis BSO 464 revealed the presence of eight plasmids, with plasmids 1, 2, and 3 containing horA, horC, and hitA, respectively. To investigate the roles that these and the other five plasmids play in L. brevis BSO 464 growth in beer, plasmid curing with novobiocin was used to derive 10 plasmid variants. Multiplex PCRs were utilized to determine the presence or absence of each plasmid, and how plasmid loss affected hop tolerance and growth in degassed (noncarbonated) beer was assessed. Loss of three of the eight plasmids was found to affect hop tolerance and growth in beer. Loss of plasmid 2 (horC and 28 other genes) had the most dramatic effect, with loss of plasmid 4 (120 genes) and plasmid 8 (47 genes) having significant, but smaller, impacts. These results support the contention that genes on mobile genetic elements are essential for bacterial growth in beer and that beer spoilage ability is not dependent solely on the three previously described hop tolerance genes or on the chromosome of a beer spoilage LAB isolate.

  14. Growth characteristics of Lactobacillus brevis KB290 in the presence of bile.

    PubMed

    Kimoto-Nira, Hiromi; Suzuki, Shigenori; Suganuma, Hiroyuki; Moriya, Naoko; Suzuki, Chise

    2015-10-01

    Live Lactobacillus brevis KB290 have several probiotic activities, including immune stimulation and modulation of intestinal microbial balance. We investigated the adaptation of L. brevis KB290 to bile as a mechanism of intestinal survival. Strain KB290 was grown for 5 days at 37 °C in tryptone-yeast extract-glucose (TYG) broth supplemented with 0.5% sodium acetate (TYGA) containing 0.15%, 0.3%, or 0.5% bile. Growth was determined by absorbance at 620 nm or by dry weight. Growth was enhanced as the broth's bile concentration increased. Bile-enhanced growth was not observed in TYG broth or with xylose or fructose as the carbon source, although strain KB290 could assimilate these sugars. Compared with cells grown without bile, cells grown with bile had twice the cell yield (dry weight) and higher hydrophobicity, which may improve epithelial adhesion. Metabolite analysis revealed that bile induced more lactate production by glycolysis, thus enhancing growth efficiency. Scanning electron microscopy revealed that cells cultured without bile for 5 days in TYGA broth had a shortened rod shape and showed lysis and aggregation, unlike cells cultured for 1 day; cells grown with bile for 5 days had an intact rod shape and rarely appeared damaged. Cellular material leakage through autolysis was lower in the presence of bile than in its absence. Thus lysis of strain KB290 cells cultured for extended periods was suppressed in the presence of bile. This study provides new role of bile and sodium acetate for retaining an intact cell shape and enhancing cell yield, which are beneficial for intestinal survival.

  15. Effect of Lactobacillus brevis 119-2 isolated from Tsuda kabu red turnips on cholesterol levels in cholesterol-administered rats.

    PubMed

    Watanabe, Shinobu; Katsube, Takuya; Hattori, Hideki; Sato, Hiromasa; Ishijima, Tomoko; Nakai, Yuji; Abe, Keiko; Sonomoto, Kenji

    2013-07-01

    In a previous in vitro study, we reported that the potential mechanism of the cholesterol-lowering effect of Lactobacillus brevis 119-2 isolated from turnip Tsuda kabu was the incorporation of cholesterol to cell membrane. In this study, we analyzed serum cholesterol and hepatic gene expression of Sprague-Dawley (SD) rats kept on a cholesterol diet with or without L. brevis 119-2 for 2 weeks, to evaluate the cholesterol-lowering effect in vivo. Serum cholesterol levels were significantly reduced in SD rats kept on a diet including L. brevis 119-2 compared with that in SD rats kept on a diet without L. brevis 119-2, and both viable and dead L. brevis 119-2 induced this effect. Hepatic gene analysis by DNA microarray suggested that the potential mechanism of the cholesterol-lowering effect of L. brevis 119-2 in vivo was inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase activity by insulin induced gene (Insig) protein, and induction of catabolism of cholesterol to bile acid by Cyp7a1 (cytochrome P450 a1). In addition, we found that inclusion of L. brevis 119-2 in the diet decreased serum low density lipoprotein (LDL) cholesterol levels by inducing overexpression of the LDL receptor gene. In contrast, Lactobacillus acidophilus ATCC 43121 increased high density lipoprotein cholesterol levels by inducing overexpression of the ATP-binding cassette sub-family. A member 1 (Abca1) and Angiopoietin-like 3 (Angptl3) genes. These results suggest that L. brevis 119-2 decreases the risk of atherosclerosis by lowering serum cholesterol, ameliorating the effect of fatty liver.

  16. High level heterologous protein production in Lactococcus and Lactobacillus using a new secretion system based on the Lactobacillus brevis S-layer signals.

    PubMed

    Savijoki, K; Kahala, M; Palva, A

    1997-02-28

    A secretion cassette, based on the expression and secretion signals of a S-layer protein (SlpA) from Lactobacillus brevis, was constructed. E. coli beta-lactamase (Bla) was used as the reporter protein to determine the functionality of the S-layer signals for heterologous expression and secretion in Lactococcus lactis, Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus gasseri and Lactobacillus casei using a low-copy-number plasmid derived from pGK12. In all hosts tested, the bla gene was expressed under the slpA signals and all Bla activity was secreted to the culture medium. The Lb. brevis S-layer promoters were very efficiently recognized in L. lactis, Lb. brevis and Lb. plantarum, whereas in Lb. gasseri the slpA promoter region appeared to be recognized at a lower level and in Lb. casei the level of transcripts was below the detection limit. The production of Bla was mainly restricted to the exponential phase of growth. The highest yield of Bla was obtained with L. lactis and Lb. brevis. Without pH control, substantial degradation of Bla occurred during prolonged cultivations with all lactic acid bacteria (LAB) tested. When growing L. lactis and Lb. brevis under pH control, the Bla activity could be stabilized also at the stationary phase. L. lactis produced up to 80 mg/l of Bla which to our knowledge represents the highest amount of a heterologous protein secreted by LAB so far. The short production phase implied a very high rate of secretion with a calculated value of 5 x 10(5) Bla molecules/cell per h. Such a high rate was also observed with Lb. plantarum, whereas in Lb. brevis the competition between the wild type slpA gene and the secretion construct probably lowered the rate of Bla production. The results obtained indicate wide applicability of the Lb. brevis slpA signals for efficient protein production and secretion in LAB.

  17. Growth and bile tolerance of Lactobacillus brevis strains isolated from Japanese pickles in artificial digestive juices and contribution of cell-bound exopolysaccharide to cell aggregation.

    PubMed

    Suzuki, Shigenori; Honda, Hiroyuki; Suganuma, Hiroyuki; Saito, Tadao; Yajima, Nobuhiro

    2014-03-01

    Cell-bound exopolysaccharide (EPS) of the aggregable strain Lactobacillus brevis KB290 isolated from traditional Japanese pickles has been reported to protect against the effects of bile. However, there are no reports of bile tolerance mechanisms for other L. brevis strains that have aggregability. To elucidate the mechanism of bile tolerance of L. brevis KB290, we found 8 aggregable L. brevis strains out of 121 L. brevis strains isolated from traditional Japanese fermented pickles. We estimated their growth in artificial digestive juice and the amount of cell-bound EPS. We found 3 types of aggregation for these strains: filiform (<1 mm), medium floc (1-5 mm), or large floc (>5 mm). There was no significant difference in growth between nonaggregable and aggregable strains in the artificial digestive juice. The large floc strains selected from the aggregation strains showed significantly higher growth in the artificial digestive juice than nonaggregable strains. In medium and large floc strains, cell-bound EPS, mainly consisting of glucose, N-acetylglucosamine, and N-acetylmannosamine, were observed. The amount of EPS and each strain's growth index showed a positive correlation. We conclude that aggregable L. brevis strains were also protected by cell-bound EPS.

  18. Individual-based modelling of the development and transport of a Karenia mikimotoi bloom on the North-west European continental shelf.

    PubMed

    Gillibrand, P A; Siemering, B; Miller, P I; Davidson, K

    2016-03-01

    In 2006, a large and prolonged bloom of the dinoflagellate Karenia mikimotoi occurred in Scottish coastal waters, causing extensive mortalities of benthic organisms including annelids and molluscs and some species of fish (Davidson et al., 2009). A coupled hydrodynamic-algal transport model was developed to track the progression of the bloom around the Scottish coast during June-September 2006 and hence investigate the processes controlling the bloom dynamics. Within this individual-based model, cells were capable of growth, mortality and phototaxis and were transported by physical processes of advection and turbulent diffusion, using current velocities extracted from operational simulations of the MRCS ocean circulation model of the North-west European continental shelf. Vertical and horizontal turbulent diffusion of cells are treated using a random walk approach. Comparison of model output with remotely sensed chlorophyll concentrations and cell counts from coastal monitoring stations indicated that it was necessary to include multiple spatially distinct seed populations of K. mikimotoi at separate locations on the shelf edge to capture the qualitative pattern of bloom transport and development. We interpret this as indicating that the source population was being transported northwards by the Hebridean slope current from where colonies of K. mikimotoi were injected onto the continental shelf by eddies or other transient exchange processes. The model was used to investigate the effects on simulated K. mikimotoi transport and dispersal of: (1) the distribution of the initial seed population; (2) algal growth and mortality; (3) water temperature; (4) the vertical movement of particles by diurnal migration and eddy diffusion; (5) the relative role of the shelf edge and coastal currents; (6) the role of wind forcing. The numerical experiments emphasized the requirement for a physiologically based biological model and indicated that improved modelling of future blooms

  19. Small angle X-ray scattering and transmission electron microscopy study of the Lactobacillus brevis S-layer protein

    NASA Astrophysics Data System (ADS)

    Jääskeläinen, Pentti; Engelhardt, Peter; Hynönen, Ulla; Torkkeli, Mika; Palva, Airi; Serimaa, Ritva

    2010-10-01

    The structure of self-assembly domain containing recombinant truncation mutants of Lactobacillus brevis surface layer protein SlpA in aqueous solution was studied using small-angle X-ray scattering and transmission electron microscopy. The proteins were found out to interact with each other forming stable globular oligomers of about 10 monomers. The maximum diameter of the oligomers varied between 75 Å and 435 Å.

  20. Biogenic amine production by the wine Lactobacillus brevis IOEB 9809 in systems that partially mimic the gastrointestinal tract stress

    PubMed Central

    2012-01-01

    Background Ingestion of fermented foods containing high levels of biogenic amines (BA) can be deleterious to human health. Less obvious is the threat posed by BA producing organisms contained within the food which, in principle, could form BA after ingestion even if the food product itself does not initially contain high BA levels. In this work we have investigated the production of tyramine and putrescine by Lactobacillus brevis IOEB 9809, of wine origin, under simulated gastrointestinal tract (GIT) conditions. Results An in vitro model that simulates the normal physiological conditions in the human digestive tract, as well as Caco-2 epithelial human cell lines, was used to challenge L. brevis IOEB 9809, which produced both tyramine and putrescine under all conditions tested. In the presence of BA precursors and under mild gastric stress, a correlation between enhancement of bacterial survival and a synchronous transcriptional activation of the tyramine and putrescine biosynthetic pathways was detected. High levels of both BA were observed after exposure of the bacterium to Caco-2 cells. Conclusions L. brevis IOEB 9809 can produce tyramine and putrescine under simulated human digestive tract conditions. The results indicate that BA production may be a mechanism that increases bacterial survival under gastric stress. PMID:23113922

  1. Genomic Analysis by Deep Sequencing of the Probiotic Lactobacillus brevis KB290 Harboring Nine Plasmids Reveals Genomic Stability

    PubMed Central

    Fukao, Masanori; Oshima, Kenshiro; Morita, Hidetoshi; Toh, Hidehiro; Suda, Wataru; Kim, Seok-Won; Suzuki, Shigenori; Yakabe, Takafumi; Hattori, Masahira; Yajima, Nobuhiro

    2013-01-01

    We determined the complete genome sequence of Lactobacillus brevis KB290, a probiotic lactic acid bacterium isolated from a traditional Japanese fermented vegetable. The genome contained a 2,395,134-bp chromosome that housed 2,391 protein-coding genes and nine plasmids that together accounted for 191 protein-coding genes. KB290 contained no virulence factor genes, and several genes related to presumptive cell wall-associated polysaccharide biosynthesis and the stress response were present in L. brevis KB290 but not in the closely related L. brevis ATCC 367. Plasmid-curing experiments revealed that the presence of plasmid pKB290-1 was essential for the strain's gastrointestinal tract tolerance and tendency to aggregate. Using next-generation deep sequencing of current and 18-year-old stock strains to detect low frequency variants, we evaluated genome stability. Deep sequencing of four periodic KB290 culture stocks with more than 1,000-fold coverage revealed 3 mutation sites and 37 minority variation sites, indicating long-term stability and providing a useful method for assessing the stability of industrial bacteria at the nucleotide level. PMID:23544154

  2. The Mechanism of the Tyrosine Transporter TyrP Supports a Proton Motive Tyrosine Decarboxylation Pathway in Lactobacillus brevis

    PubMed Central

    Wolken, Wout A. M.; Lucas, Patrick M.; Lonvaud-Funel, Aline; Lolkema, Juke S.

    2006-01-01

    The tyrosine decarboxylase operon of Lactobacillus brevis IOEB9809 contains, adjacent to the tyrosine decarboxylase gene, a gene for TyrP, a putative tyrosine transporter. The two genes potentially form a proton motive tyrosine decarboxylation pathway. The putative tyrosine transporter gene of L. brevis was expressed in Lactococcus lactis and functionally characterized using right-side-out membranes. The transporter very efficiently catalyzes homologous tyrosine-tyrosine exchange and heterologous exchange between tyrosine and its decarboxylation product tyramine. Tyrosine-tyramine exchange was shown to be electrogenic. In addition to the exchange mode, the transporter catalyzes tyrosine uniport but at a much lower rate. Analysis of the substrate specificity of the transporter by use of a set of 19 different tyrosine substrate analogues showed that the main interactions between the protein and the substrates involve the amino group and the phenyl ring with the para hydroxyl group. The carboxylate group that is removed in the decarboxylation reaction does not seem to contribute to the affinity of the protein for the substrates significantly. The properties of the TyrP protein are those typical for precursor-product exchangers that operate in proton motive decarboxylation pathways. It is proposed that tyrosine decarboxylation in L. brevis results in proton motive force generation by an indirect proton pumping mechanism. PMID:16513749

  3. Determination of some heavy metal concentrations in razor clam (Solen brevis) from Tanjung Lumpur coastal waters, Pahang, Malaysia.

    PubMed

    Kamaruzzaman, B Y; Zahir, M S; John, B Akbar; Waznah, A Siti; Jalal, K C A; Shahbudin, S; Al-Barwani, S M; Goddard, J S

    2010-12-15

    An effort to analyze selected heavy metal accumulation by the razor clam (Solen brevis) from Tanjung Lumpur was conducted on January to April 2010. A total of fifty individuals of Razor clam Solen brevis were sampled and metals such as Iron (Fe), Zinc (Zn), Copper (Cu), Manganese (Mn), Lead (Pb) and Cadmium (Cd) Concentrations were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Among the metals Fe occurred in elevated concentration in the soft tissue of razor clam followed by Zn. Cd was found to be in least concentration in the sample. Mean concentration of Fe, Zn, Mn, Cu, Cd and Pb in the soft tissue were 415.2 +/- 56.52, 87.74 +/- 11.85, 18.71 +/- 2.10, 8.64 +/- 1.75, 0.67 +/- 0.29 and 1.61 +/- 0.45 microg g(-1) dw, respectively indicating that the bioaccumulation of essential metals in the soft tissue was greater than the non essential heavy metals. Metal accumulation in the soft tissue of razor clam followed Fe > Zn > Mn > Cu > Pb > Cd order in present study. The observed concentration of acute toxicity of metals in Solen brevis (Family: Solenidae) from Tanjung Lumpur Coastal waters was lower than the permissible limit recommended by National and international standards proved that this species could be utilized for human consumption.

  4. Efficient production of artificially designed gelatins with a Bacillus brevis system.

    PubMed

    Kajino, T; Takahashi, H; Hirai, M; Yamada, Y

    2000-01-01

    Artificially designed gelatins comprising tandemly repeated 30-amino-acid peptide units derived from human alphaI collagen were successfully produced with a Bacillus brevis system. The DNA encoding the peptide unit was synthesized by taking into consideration the codon usage of the host cells, but no clones having a tandemly repeated gene were obtained through the above-mentioned strategy. Minirepeat genes could be selected in vivo from a mixture of every possible sequence encoding an artificial gelatin by randomly ligating the mixed sequence unit and transforming it into Escherichia coli. Larger repeat genes constructed by connecting minirepeat genes obtained by in vivo selection were also stable in the expression host cells. Gelatins derived from the eight-unit and six-unit repeat genes were extracellularly produced at the level of 0.5 g/liter and easily purified by ammonium sulfate fractionation and anion-exchange chromatography. The purified artificial gelatins had the predicted N-terminal sequences and amino acid compositions and a solgel property similar to that of the native gelatin. These results suggest that the selection of a repeat unit sequence stable in an expression host is a shortcut for the efficient production of repetitive proteins and that it can conveniently be achieved by the in vivo selection method. This study revealed the possible industrial application of artificially designed repetitive proteins.

  5. Silent periods in the abductor pollicis brevis muscle in patients with Parkinson's disease.

    PubMed

    Nakashima, K; Takahashi, K

    1992-01-01

    Silent periods in the abductor pollicis brevis muscle, produced by electrical stimulation of the median nerve at the wrist or the palmar side of the index finger, were studied in 14 patients with Parkinson's disease (PD) and eight control subjects. Prior to the stimulation, background electromyographic activity showed no differences between normal subjects and patients with PD. Following the H-reflex after median nerve stimulation, two suppressive phases were observed: early (SP1) and late (SP2). Electrical stimulation of the palmar side of the index finger elicited two suppressive phases at almost the same latencies. The latency and duration of SP1 and SP2 and the degree of SP1, produced by electrical stimulation of the median nerve and the palmar side of the index finger in patients with PD, were normal. The degree of SP2 produced by electrical stimulation of the palmar side of the index finger in patients with PD was lower than that in normal subjects, although the degree of SP2 produced by median nerve stimulation in patients with PD did not differ from that in normal subjects. Suppression produced by cutaneous stimulation in the Parkinsonian hand may be low.

  6. Crystallization and preliminary crystallographic analysis of a flavoprotein NADH oxidase from Lactobacillus brevis

    PubMed Central

    Kuzu, Mutlu; Niefind, Karsten; Hummel, Werner; Schomburg, Dietmar

    2005-01-01

    NADH oxidase (NOX) from Lactobacillus brevis is a homotetrameric flavoenzyme composed of 450 amino acids per subunit. The molecular weight of each monomer is 48.8 kDa. The enzyme catalyzes the oxidation of two equivalents of NADH and reduces one equivalent of oxygen to yield two equivalents of water, without releasing hydrogen peroxide after the reduction of the first equivalent of NADH. Crystals of this protein were grown in the presence of 34% polyethylene glycol monomethyl ether 2000, 0.1 M sodium acetate and 0.2 M ammonium sulfate at pH 5.4. They belong to the tetragonal space group P43212, with unit-cell parameters a = 74.8, b = 95.7, c = 116.9 Å, α = γ = 90, β = 103.8°. The current diffraction limit is 4.0 Å. The self-rotation function of the native data set is consistent with a NOX tetramer in the asymmetric unit. PMID:16511087

  7. Steric vs. electronic effects in the Lactobacillus brevis ADH-catalyzed bioreduction of ketones.

    PubMed

    Rodríguez, Cristina; Borzęcka, Wioleta; Sattler, Johann H; Kroutil, Wolfgang; Lavandera, Iván; Gotor, Vicente

    2014-01-28

    Lactobacillus brevis ADH (LBADH) is an alcohol dehydrogenase that is commonly employed to reduce alkyl or aryl ketones usually bearing a methyl, an ethyl or a chloromethyl as a small ketone substituent to the corresponding (R)-alcohols. Herein we have tested a series of 24 acetophenone derivatives differing in their size and electronic properties for their reduction employing LBADH. After plotting the relative activity against the measured substrate volumes we observed that apart from the substrate size other effects must be responsible for the activity obtained. Compared to acetophenone (100% relative activity), other small substrates such as propiophenone, α,α,α-trifluoroacetophenone, α-hydroxyacetophenone, and benzoylacetonitrile had relative activities lower than 30%, while medium-sized ketones such as α-bromo-, α,α-dichloro-, and α,α-dibromoacetophenone presented relative activities between 70% and 550%. Moreover, the comparison between the enzymatic activity and the obtained final conversions using an excess or just 2.5 equiv. of the hydrogen donor 2-propanol, denoted again deviations between them. These data supported that these hydrogen transfer (HT) transformations are mainly thermodynamically controlled. For instance, bulky α-halogenated derivatives could be quantitatively reduced by LBADH even employing 2.5 equiv. of 2-propanol independently of their kinetic values. Finally, we found good correlations between the IR absorption band of the carbonyl groups and the degrees of conversion obtained in these HT processes, making this simple method a convenient tool to predict the success of these transformations.

  8. Efficient bioconversion of L-glutamate to γ-aminobutyric acid by Lactobacillus brevis resting cells.

    PubMed

    Shi, Xiufeng; Chang, Chuanyou; Ma, Shenxi; Cheng, Yibing; Zhang, Jun; Gao, Qiang

    2016-05-07

    This work investigated the efficient bioconversion process of L-glutamate to GABA by Lactobacillus brevis TCCC 13007 resting cells. The optimal bioconversion system was composed of 50 g/L 48 h cultivated wet resting cells, 0.1 mM pyridoxal phosphate in glutamate-containing 0.6 M citrate buffer (pH 4.5) and performed at 45 °C and 180 rpm. By 10 h bioconversion at the ratio of 80 g/L L-glutamic acid to 240 g/L monosodium glutamate, the final titer of GABA reached 201.18 g/L at the molar bioconversion ratio of 99.4 %. This process presents a potential for industrial and commercial applications and also offers a promising feasibility of continuous GABA production coupled with fermentation. Besides, the built kinetics model revealed that the optimum operating conditions were 45 °C and pH 4.5, and the bioconversion kinetics at low ranges of substrate concentration (0 < S < 80 g/L) was assumed to follow the classical Michaelis-Menten equation.

  9. Cell-bound exopolysaccharides of Lactobacillus brevis KB290: protective role and monosaccharide composition.

    PubMed

    Suzuki, Shigenori; Yakabe, Takafumi; Suganuma, Hiroyuki; Fukao, Masanori; Saito, Tadao; Yajima, Nobuhiro

    2013-08-01

    We examined the survivability of Lactobacillus brevis KB290 and derivative strain KB392 in artificial digestive juices and bile salts. The strains have similar membrane fatty acids but different amounts of cell-bound exopolysaccharides (EPS). In artificial digestive juices, KB290 showed significantly higher survivability than KB392, and homogenization, which reduced the amount of EPS in KB290 but not in KB392, reduced the survivability only of KB290. In bile salts, KB290 showed significantly higher survivability than KB392, and cell-bound EPS extraction with EDTA reduced the survivability of only KB290. Transmission electron microscopy showed there to be a greater concentration of cell-bound EPS in KB290 than in either KB392 or EDTA-treated or homogenized KB290. We conclude that KB290's cell-bound EPS (which high performance liquid chromatography showed to be made up of glucose and N-acetylglucosamine) played an important role in bile salt tolerance.

  10. Anti-inflammaging effects of Lactobacillus brevis OW38 in aged mice.

    PubMed

    Jeong, J-J; Kim, K A; Hwang, Y-J; Han, M J; Kim, D-H

    2016-11-30

    In the present study, lactic acid bacteria (LAB) strains were collected from kimchi and were screened to isolate strains that inhibit lipopolysaccharide (LPS) production by Escherichia coli and p16 expression and nuclear factor-kappa B (NF-κB) activation in LPS-stimulated macrophages. Oral administration of Lactobacillus brevis OW38 (1×10(9) cfu/mouse) to aged mice (male, 18 months old) for 8 weeks reduced the LPS level in colon fluid and blood. In addition, OW38 treatment also reduced the ratio of Firmicutes or Proteobacteria to Bacteroidetes, which was significantly higher in aged mice than in young mice. Treatment with OW38 in aged mice inhibited the expression of inflammatory markers, such as myeloperoxidase, tumour necrosis factor (TNF), and interleukin (IL)-1β, and inhibited NF-κB activation. Furthermore, it induced the expression of colonic tight junction proteins zonula occludens-1, occludin, and claudin-1. OW38 treatment also suppressed the expression of senescence markers p16, p53, and SAMHD1 in the colon and the hippocampus of aged mice. In addition, it significantly restored spontaneous alternation as well as the expression of brain-derived neurotrophic factor and doublecortin in aged mice compared to that in young mice (P<0.05). Based on these findings, we conclude that OW38 treatment may ameliorate aging-associated colitis and memory impairment by inhibiting gut microbiota LPS production, NF-κB activation, and p16 expression.

  11. Heterogeneity between and within Strains of Lactobacillus brevis Exposed to Beer Compounds.

    PubMed

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2017-01-01

    This study attempted to investigate the physiological response of six Lactobacillus brevis strains to hop stress, with and without the addition of Mn(2+) or ethanol. Based on the use of different fluorescent probes, cell viability and intracellular pH (pHi) were assessed by fluorescence microscopy combined with flow cytometry, at the single cell level. The combined approach was faster than the traditional colony based method, but also provided additional information about population heterogeneity with regard to membrane damage and cell size reduction, when exposed to hop compounds. Different physiological subpopulations were detected under hop stress in both hop tolerant and sensitive strains. A large proportion of cells were killed in all the tested strains, but a small subpopulation from the hop tolerant strains eventually recovered as revealed by pHi measurements. Furthermore, a short term protection against hop compounds was obtained for both hop tolerant and sensitive strains, by addition of high concentration of Mn(2+). Addition of ethanol in combination with hop compounds caused an additional short term increase in damaged subpopulation, but the subsequent growth suggested that the presence of ethanol provides a slight cross resistance toward hop compounds.

  12. Maltose phosphorylase from Lactobacillus brevis: purification, characterization, and application in a biosensor for ortho-phosphate.

    PubMed

    Hüwel, S; Haalck, L; Conrath, N; Spener, F

    1997-11-01

    With the goal to obtain maltose phosphorylase as a tool to determine ortho-phosphate, the enzyme from Lactobacillus brevis was purified to 98% by an expeditious FPLC-aided procedure which included anion exchange chromatography, gel filtration, and hydroxyapatite chromatography. The native maltose phosphorylase had a molecular mass of 196 kDa and consisted of two 88 kDa subunits. In isoelectric focusing two isoforms with pI values of 4.2 and 4.6 were observed. Maximum enzyme activity was obtained at 36 degrees C and pH 6.5 and was independent of pyridoxal 5'-phosphate. The apparent K(m) values with maltose and phosphate as substrates were 0.9 mmol l-1 and 1.8 mmol l-1, respectively. Maltose phosphorylase could be stored in 10 mM phosphate buffer pH 6.5 at 4 degrees C with a loss of activity of only 7% up to 6 months. The stability of the enzyme at high temperatures was enhanced significantly using additives like phosphate, citrate, and imidazole. The purified maltose phosphorylase was used as key enzyme in a phosphate sensor consisting of maltose phosphorylase and glucose oxidase. A detection limit of 0.1 microM phosphate was observed and the sensor response was linear in the range between 0.5 and 10 microM.

  13. Ecophenotypic Variation and Developmental Instability in the Late Cretaceous Echinoid Micraster brevis (Irregularia; Spatangoida)

    PubMed Central

    Schlüter, Nils

    2016-01-01

    The Late Cretaceous echinoid genus Micraster (irregular echinoids, Spatangoida) is one of the most famous examples of a continuous evolutionary lineage in invertebrate palaeontology. The influence of the environment on the phenotype, however, was not tested so far. This study analyses differences in phenotypical variations within three populations of Micraster (Gibbaster) brevis from the early Coniacian, two from the Münsterland Cretaceous Basin (Germany) and one from the North Cantabrian Basin (Spain). The environments of the Spanish and the German sites differed by their sedimentary characteristics, which are generally a crucial factor for morphological adaptations in echinoids. Most of the major phenotypical variations (position of the ambitus, periproct and development of the subanal fasciole) among the populations can be linked to differences in their host sediments. These phenotypic variations are presumed to be an expression of phenotpic plasticiy, which has not been considered in Micraster in previous studies. Two populations (Erwitte area, Germany; Liencres area, Spain) were tested for stochastic variation (fluctuating asymmetry) due to developmental instability, which was present in all studied traits. However, differences in the amount of fluctuating asymmetry between both populations were recognised only in one trait (amount of pore pairs in the anterior paired petals). The results strengthen previous assumptions on ecophenotypic variations in Micraster. PMID:26849648

  14. Halorientalis brevis sp. nov., Isolated from an Inland Salt Lake of China.

    PubMed

    Yuan, Pan-Pan; Yin, Shuai; Han, Dong; Zhang, Wen-Jiao; Cui, Heng-Lin

    2015-09-01

    Halophilic archaeal strain YC89(T) was isolated from Yuncheng salt lake in Shanxi, China. Cells from strain YC89(T) were short rods, lysed in distilled water, stained Gram-negative and formed red-pigmented colonies on agar plate. Strain YC89(T) was able to grow at 25-50°C (optimum 37°C), at 1.4-4.8 M NaCl (optimum 2.6-3.1 M), at 0-1.0 M MgCl2 (optimum 0.3 M) and at pH 6.0-9.5 (optimum pH 7.5). The major polar lipids are phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, sulfated mannosyl glucosyl diether and two unknown glycolipids. 16S rRNA gene analysis revealed that strain YC89(T) was phylogenetically related to Halorientalis persicus D108(T) (95.6% nucleotide identity) and H. regularis TNN28(T) (95.3% nucleotide identity). The rpoB' gene similarities between strain YC89(T) and H. persicus IBRC-M 10043(T) and H. regularis TNN28(T) were 88.1 and 88.0%, respectively. The DNA G+C content of strain YC89(T) was determined to be 61.3 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain YC89(T) (=CGMCC 1.12125(T) = JCM 18366(T)) represents a new species of Halorientalis, for which the name H. brevis sp. nov. is proposed.

  15. Lateral line analogue aids vision in successful predator evasion for the brief squid, Lolliguncula brevis.

    PubMed

    York, Carly A; Bartol, Ian K

    2014-07-15

    Cephalopods have visual and mechanoreception systems that may be employed to sense and respond to an approaching predator. While vision presumably plays the dominant role, the importance of the lateral line analogue for predator evasion has not been examined in cephalopods. To test the respective roles of vision and the lateral line analogue, brief squid, Lolliguncula brevis, were observed in the presence of summer flounder, Paralichthys dentatus, under light and dark conditions with their lateral line analogue intact and ablated. Hair cell ablation was achieved through a pharmacological technique used for the first time on a cephalopod. The proportion of predator-prey interactions survived was significantly higher in the light non-ablated and light ablated groups compared with the dark ablated group. The mean number of interactions survived varied across treatment groups with the light non-ablated group having significantly more success than the light ablated, dark non-ablated and dark ablated groups. These findings demonstrate that although vision is the primary sense, the lateral line analogue also contributes to predator evasion in squid.

  16. Molecular mechanisms behind the antimicrobial activity of hop iso-α-acids in Lactobacillus brevis.

    PubMed

    Schurr, Benjamin C; Hahne, Hannes; Kuster, Bernhard; Behr, Jürgen; Vogel, Rudi F

    2015-04-01

    The main bittering component in beer, hop iso-α-acids, have been characterised as weak acids, which act as ionophores impairing microbial cells' function under acidic conditions as present in beer. Besides medium pH, divalent cations play a central role regarding the efficacy of the antimicrobial effect. The iso-α-acids' non-bitter derivatives humulinic acids can be found in isomerised hop extracts and can be generated during hop storage. Therefore, they have been under investigation concerning their influence on beer sensory properties. This study sketches the molecular mechanism behind iso-α-acids' antimicrobial activity in Lactobacillus (L.) brevis regarding their ionophore activity versus the dependence of the inhibitory potential on manganese binding, and suggests humulinic acids as novel tasteless food preservatives. We designed and synthesised chemically modified iso-α-acids to enhance the basic understanding of the molecular mechanism of antimicrobial iso-α-acids. It could be observed that a manganese-binding dependent transmembrane redox reaction (oxidative stress) plays a crucial role in inhibition. Privation of an acidic hydroxyl group neither erased ionophore activity, nor did it entirely abolish antimicrobial activity. Humulinic acids proved to be highly inhibitory, even outperforming iso-α-acids.

  17. Neuromuscular manifestations of work-related myalgia in women specific to extensor carpi radialis brevis.

    PubMed

    Green, Howard J; Ranney, Don; Kyle, Natasha; Lounsbury, David; Smith, Ian C; Stewart, Riley; Thomas, Melissa M; Tick, Heather; Tupling, A Russell

    2017-04-01

    This study assessed neuromuscular function in the extensor carpi radialis brevis (ECRB) of female workers diagnosed with work-related myalgia (WRM, n = 14, age 45.2 ± 1.9 years) and the ECRB of healthy controls (CON, n = 10, age 34.6 ± 2.5 years). Groups were compared on voluntary and electrically evoked functional responses at rest (Pre), immediately following a 5 min repetitive task (Post-0) performed at 60% maximal voluntary contraction (MVC), and after 5 min of recovery (Post-5). Despite near complete motor unit activation (MUA) (CON 98% ± 1% vs. WRM 99% ± 1%), at Pre, WRM produced 26% less (P < 0.05) MVC force than CON. Following an MVC, twitch force was increased (P < 0.05) by 94% ± 13% and 54% ± 11% in CON and WRM, respectively (CON vs. WRM; P < 0.05). The peak force and the maximal rates of force development and decline of electrically evoked contractions (10-100 Hz) were generally depressed (P < 0.05) at Post-0 and Post-5 relative to Pre. The response pattern to increasing frequencies of stimulation was not different (P > 0.05) between groups and MUA was not impaired (CON 97% ± 1% vs. WRM 97% ± 1%; P > 0.05). In conclusion, the peripheral weakness observed in the ECRB in WRM at rest does not result in abnormal fatigue or recovery responses after performing a task controlled for relative demand (60% MVC).

  18. Using DNA barcoding to link cystacanths and adults of the acanthocephalan Polymorphus brevis in central Mexico.

    PubMed

    Alcántar-Escalera, F J; García-Varela, M; Vázquez-Domínguez, E; Pérez-Ponce de León, G

    2013-11-01

    In parasitic organisms, particularly helminths, the usage of the mitochondrial cytochrome c oxidase subunit I gene as the standard DNA barcoding region for species identification and discovery has been very limited. Here, we present an integrated study, based on both DNA barcoding and morphological analyses, for acanthocephalans belonging to the genus Polymorphus, whose larvae (cystacanths) are commonly found in the mesentery of freshwater fishes, while adults are found in the intestine of fish-eating birds. The alpha taxonomy of parasitic helminths is based on adult morphological traits, and because of that larval forms cannot be identified to species level based on morphology alone. DNA barcoding offers an alternative tool for linking larval stages of parasitic organisms to known adults. We sequenced cystacanths collected from freshwater fishes in localities across central Mexico and adults obtained from fish-eating birds, to determine whether they were conspecific. To corroborate the molecular results, we conducted a morphometric analysis with 'Proboscis profiler', which is a software tool developed to detect heterogeneity in morphologically similar acanthocephalans based on the multivariate statistical analysis of proboscis hook dimensions. Both sources of information indicate that cystacanths infecting freshwater fishes in central Mexico belong to a single species, Polymorphus brevis.

  19. Heterogeneity between and within Strains of Lactobacillus brevis Exposed to Beer Compounds

    PubMed Central

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2017-01-01

    This study attempted to investigate the physiological response of six Lactobacillus brevis strains to hop stress, with and without the addition of Mn2+ or ethanol. Based on the use of different fluorescent probes, cell viability and intracellular pH (pHi) were assessed by fluorescence microscopy combined with flow cytometry, at the single cell level. The combined approach was faster than the traditional colony based method, but also provided additional information about population heterogeneity with regard to membrane damage and cell size reduction, when exposed to hop compounds. Different physiological subpopulations were detected under hop stress in both hop tolerant and sensitive strains. A large proportion of cells were killed in all the tested strains, but a small subpopulation from the hop tolerant strains eventually recovered as revealed by pHi measurements. Furthermore, a short term protection against hop compounds was obtained for both hop tolerant and sensitive strains, by addition of high concentration of Mn2+. Addition of ethanol in combination with hop compounds caused an additional short term increase in damaged subpopulation, but the subsequent growth suggested that the presence of ethanol provides a slight cross resistance toward hop compounds. PMID:28261191

  20. Extensor Pollicis Brevis tendon damage presenting as de Quervain’s disease following kettlebell training

    PubMed Central

    2013-01-01

    Kettlebell exercises are more efficient for an athlete to increase his or her muscle strength. However it carries the risk of injury especially in the beginners. A 39 year old gentleman came to our clinic with radial sided wrist pain following kettlebell exercises. Clinically patient had swelling and tenderness over the tendons in the first dorsal wrist compartment, besides Finklesten test was positive. Patient had a decreased excursion of the thumb when compared to the opposite side. Ultrasound/MRI scan revealed asymmetric thickening of the 1st compartment extensors extending from the base of the thumb to the wrist joint. Besides injury to the Extensor Pollicis Brevis (EPB) tendon by repetitive impact from kettlebell, leading to its split was identified. Detailed history showed that the injury might be due to off-centre handle holding during triceps strengthening exercises. Our report stresses the fact that kettlebell users should be taught about problems of off-center handle holding to avoid wrist injuries. Also, in Kettlebell users with De Quervains disease clinical and radiological evaluation should be done before steroid injection as this might lead to complete tendon rupture. PMID:23731737

  1. Extensor Pollicis Brevis tendon damage presenting as de Quervain's disease following kettlebell training.

    PubMed

    Karthik, Karuppaiah; Carter-Esdale, Charles William; Vijayanathan, Sanjay; Kochhar, Tony

    2013-06-03

    Kettlebell exercises are more efficient for an athlete to increase his or her muscle strength. However it carries the risk of injury especially in the beginners. A 39 year old gentleman came to our clinic with radial sided wrist pain following kettlebell exercises. Clinically patient had swelling and tenderness over the tendons in the first dorsal wrist compartment, besides Finklesten test was positive. Patient had a decreased excursion of the thumb when compared to the opposite side. Ultrasound/MRI scan revealed asymmetric thickening of the 1st compartment extensors extending from the base of the thumb to the wrist joint. Besides injury to the Extensor Pollicis Brevis (EPB) tendon by repetitive impact from kettlebell, leading to its split was identified. Detailed history showed that the injury might be due to off-centre handle holding during triceps strengthening exercises. Our report stresses the fact that kettlebell users should be taught about problems of off-center handle holding to avoid wrist injuries. Also, in Kettlebell users with De Quervains disease clinical and radiological evaluation should be done before steroid injection as this might lead to complete tendon rupture.

  2. Oral administration of heat-killed Lactobacillus brevis SBC8803 ameliorates alcoholic liver disease in ethanol-containing diet-fed C57BL/6N mice.

    PubMed

    Segawa, Shuichi; Wakita, Yoshihisa; Hirata, Hiroshi; Watari, Junji

    2008-12-10

    We examined the effect of heat-killed Lactobacillus brevis (L. brevis) SBC8803 on the development of alcoholic liver disease using ethanol-containing diet-fed mice. Heat-killed L. brevis was orally administered at a dose of 100 or 500 mg/kg once a day for 35 days. Alcoholic liver injury was examined by measuring the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in a serum, and the alcoholic fatty liver was assessed from the content of triglyceride (TG) and total cholesterol in the liver. Quantitative RT-PCR was used to examine mRNA expression of tumor necrosis factor (TNF)-alpha, sterol regulatory element-binding protein (SREBP)-1, SREBP-2, and peroxisome proliferator-activated receptor alpha (PPARalpha) in the liver, as well as E-cadherin, Zonula occludens 1 (ZO-1), and heat shock protein (Hsp) 25 in the small intestine. Oral administration of L. brevis significantly inhibited an increase in the level of serum ALT and AST, as well as the content of TG and total cholesterol in the liver caused by ethanol intake. L. brevis supplementation suppressed the overexpression of TNF-alpha, SREBP-1, and SREBP-2 mRNA in the liver induced by ethanol intake and up-regulated the expression of Hsp25 mRNA in the small intestine. These results suggest that L. brevis ameliorated the ethanol-induced liver injury and the fatty liver by suppressing the up-regulation of TNF-alpha and SREBPs in the liver. We speculate that the inhibition of TNF-alpha and SREBPs up-regulation by L. brevis is due to the inhibition of gut-derived endotoxin migration into the liver through the enhancement of intestinal barrier function by the induction of cytoprotective Hsps.

  3. Common Distribution of gad Operon in Lactobacillus brevis and its GadA Contributes to Efficient GABA Synthesis toward Cytosolic Near-Neutral pH

    PubMed Central

    Wu, Qinglong; Tun, Hein Min; Law, Yee-Song; Khafipour, Ehsan; Shah, Nagendra P.

    2017-01-01

    Many strains of lactic acid bacteria (LAB) and bifidobacteria have exhibited strain-specific capacity to produce γ-aminobutyric acid (GABA) via their glutamic acid decarboxylase (GAD) system, which is one of amino acid-dependent acid resistance (AR) systems in bacteria. However, the linkage between bacterial AR and GABA production capacity has not been well established. Meanwhile, limited evidence has been provided to the global diversity of GABA-producing LAB and bifidobacteria, and their mechanisms of efficient GABA synthesis. In this study, genomic survey identified common distribution of gad operon-encoded GAD system in Lactobacillus brevis for its GABA production among varying species of LAB and bifidobacteria. Importantly, among four commonly distributed amino acid-dependent AR systems in Lb. brevis, its GAD system was a major contributor to maintain cytosolic pH homeostasis by consuming protons via GABA synthesis. This highlights that Lb. brevis applies GAD system as the main strategy against extracellular and intracellular acidification demonstrating its high capacity of GABA production. In addition, the abundant GadA retained its activity toward near-neutral pH (pH 5.5–6.5) of cytosolic acidity thus contributing to efficient GABA synthesis in Lb. brevis. This is the first global report illustrating species-specific characteristic and mechanism of efficient GABA synthesis in Lb. brevis. PMID:28261168

  4. The Synergic Anti-inflammatory Impact of Gleditsia sinensis Lam. and Lactobacillus brevis KY21 on Intestinal Epithelial Cells in a DSS-induced Colitis Model.

    PubMed

    Kim, Younghoon; Koh, Ji Hoon; Ahn, Young Jun; Oh, Sejong; Kim, Sea Hun

    2015-01-01

    We investigated the synergic anti-inflammatory activity of Gleditsia sinensis Lam. (GS) extract and Lactobacillus brevis KY21 both in vitro and in vivo. Western blot analysis and immunostaining showed that AKT phosphorylation that increased by the exposure of LPS were significantly decreased by the presence of either GS extract or L. brevis KY21. In addition, p65 intracellular transport was critically inhibited by GS extract and L. brevis KY21. We further studied these effects using an in vivo dextran sulfate sodium (DSS)-induced mouse model. Body weight, food intake, and clinical scores were dramatically decreased after treatment with DSS, whereas these effects were palliated by the addition of GS extract and L. brevis KY21. Importantly, transcription of genes encoding pro-inflammatory cytokines including IL-1β, TNF-α, and IFN-γ in mesenteric lymph nodes (MLN) and the spleen were increased by DSS treatment, whereas they were inhibited by the presence of GS extract and L. brevis KY21.

  5. Common Distribution of gad Operon in Lactobacillus brevis and its GadA Contributes to Efficient GABA Synthesis toward Cytosolic Near-Neutral pH.

    PubMed

    Wu, Qinglong; Tun, Hein Min; Law, Yee-Song; Khafipour, Ehsan; Shah, Nagendra P

    2017-01-01

    Many strains of lactic acid bacteria (LAB) and bifidobacteria have exhibited strain-specific capacity to produce γ-aminobutyric acid (GABA) via their glutamic acid decarboxylase (GAD) system, which is one of amino acid-dependent acid resistance (AR) systems in bacteria. However, the linkage between bacterial AR and GABA production capacity has not been well established. Meanwhile, limited evidence has been provided to the global diversity of GABA-producing LAB and bifidobacteria, and their mechanisms of efficient GABA synthesis. In this study, genomic survey identified common distribution of gad operon-encoded GAD system in Lactobacillus brevis for its GABA production among varying species of LAB and bifidobacteria. Importantly, among four commonly distributed amino acid-dependent AR systems in Lb. brevis, its GAD system was a major contributor to maintain cytosolic pH homeostasis by consuming protons via GABA synthesis. This highlights that Lb. brevis applies GAD system as the main strategy against extracellular and intracellular acidification demonstrating its high capacity of GABA production. In addition, the abundant GadA retained its activity toward near-neutral pH (pH 5.5-6.5) of cytosolic acidity thus contributing to efficient GABA synthesis in Lb. brevis. This is the first global report illustrating species-specific characteristic and mechanism of efficient GABA synthesis in Lb. brevis.

  6. The Synergic Anti-inflammatory Impact of Gleditsia sinensis Lam. and Lactobacillus brevis KY21 on Intestinal Epithelial Cells in a DSS-induced Colitis Model

    PubMed Central

    Kim, Younghoon; Oh, Sejong

    2015-01-01

    We investigated the synergic anti-inflammatory activity of Gleditsia sinensis Lam. (GS) extract and Lactobacillus brevis KY21 both in vitro and in vivo. Western blot analysis and immunostaining showed that AKT phosphorylation that increased by the exposure of LPS were significantly decreased by the presence of either GS extract or L. brevis KY21. In addition, p65 intracellular transport was critically inhibited by GS extract and L. brevis KY21. We further studied these effects using an in vivo dextran sulfate sodium (DSS)-induced mouse model. Body weight, food intake, and clinical scores were dramatically decreased after treatment with DSS, whereas these effects were palliated by the addition of GS extract and L. brevis KY21. Importantly, transcription of genes encoding pro-inflammatory cytokines including IL-1β, TNF-α, and IFN-γ in mesenteric lymph nodes (MLN) and the spleen were increased by DSS treatment, whereas they were inhibited by the presence of GS extract and L. brevis KY21. PMID:26761887

  7. Expression and Characterization of a Novel 1,3-Propanediol Dehydrogenase from Lactobacillus brevis.

    PubMed

    Qi, Xianghui; Yun, Junhua; Qi, Yilin; Zhang, Huanhuan; Wang, Fei; Guo, Qi; Cao, Zheng

    2016-07-01

    1,3-Propanediol dehydrogenase (PDOR) is important in the biosynthesis of 1,3-propanediol. In the present study, the dhaT gene encoding PDOR was cloned from Lactobacillus brevis 6239 and expressed in Escherichia coli for the first time. Sequence analysis revealed that PDOR containing two Fe(2+)-binding motifs and a cofactor motif belongs to the type III alcohol dehydrogenase. The purified recombinant PDOR exhibited a single band of 42 kDa according to SDS-PAGE. Optimal temperatures and pH values of this dehydrogenase are 37 °C, 7.5 for reduction and 25 °C, 9.5 for oxidation, respectively. We found that PDOR was more stable in acid buffer than in alkaline condition, and 60 % of its relative activity still remained after a 2-h incubation at 37 °C. The activity of PDOR can be enhanced in the presence of Mn(2+) or Fe(2+) iron and inhibited by EDTA or PMSF by different degrees. The K m and V max of this dehydrogenase are 1.25 mM, 64.02 μM min(-1) mg(-1) for propionaldehyde and 2.26 mM, 35.05 μM min(-1) mg(-1) for 1,3-PD, respectively. Substrate specificity analysis showed that PDOR has a broad range of substrate specificities. The modeling superposition indicated that the structural differences may account for the diversity of PDORs' properties. Thus, our PDOR is a potential candidate for facilitating the 1,3-PD biosynthesis.

  8. Polyphosphate, an active molecule derived from probiotic Lactobacillus brevis, improves the fibrosis in murine colitis.

    PubMed

    Kashima, Shin; Fujiya, Mikihiro; Konishi, Hiroaki; Ueno, Nobuhiro; Inaba, Yuhei; Moriichi, Kentaro; Tanabe, Hiroki; Ikuta, Katsuya; Ohtake, Takaaki; Kohgo, Yutaka

    2015-08-01

    Inflammatory bowel disease frequently causes intestinal obstruction because of extensive fibrosis. This study investigated whether polyphosphate (poly P), an active molecule derived from Lactobacillus brevis, could improve the fibrosis in a model of chronic colitis. In this study, dextran sodium sulfate (DSS)-induced chronic colitis models and trinitrobenzene sulfonic acid (TNBS)-induced colitis models were used as models of fibrosis. To clarify the mechanism responsible for the observed effects, Caco-2/brush border epithelial (BBE) and naive T helper lymphocyte (THP)-1 cells were treated with lipopolysaccharide (LPS) to induce inflammation. Non-cancer human colon fibroblast (CCD-18) cells were treated with transforming growth factor beta 1 (TGF-β1) to induce fibrosis. The expression levels of fibrosis- and inflammation-associated molecules were evaluated by both a Western blotting analysis and reverse transcriptase-polymerase chain reaction (RT-PCR). The histologic inflammation and fibrosis were significantly improved in the group administered poly P in both the DSS and TNBS colitis models. The levels of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) were significantly decreased by poly P treatment. The expression levels of TGF-β1 and collagens in the colitis mice were decreased by poly P. The LPS-induced expressions of IL-1β and TGF-β1 in Caco-2/BBE cells and of TNF-α in THP-1 cells were reduced by poly P treatment. Poly P did not affect the expression of collagens and connective tissue growth factor in the CCD-18 cells. In conclusion, poly P suppresses intestinal inflammation and fibrosis by downregulating the expression of inflammation- and fibrosis-associated molecules in the intestinal epithelium. The administration of poly P is therefore a novel option to treat fibrosis because of chronic intestinal inflammation.

  9. Allosteric modulation of neurotoxin binding to voltage-sensitive sodium channels by Ptychodiscus brevis toxin 2.

    PubMed

    Sharkey, R G; Jover, E; Couraud, F; Baden, D G; Catterall, W A

    1987-03-01

    The effects of Ptychodiscus brevis toxin 2 (PbTx-2) on the binding of neurotoxins at four different neurotoxin receptor sites on voltage-sensitive sodium channels in rat brain synaptosomes were examined. Binding of saxitoxin at neurotoxin receptor site 1 and Leiurus quinquestriatus alpha-scorpion toxin (LqTx) at neurotoxin receptor site 3 was unaffected. PbTx-2 enhanced binding of batrachotoxinin A 20-alpha-benzoate (BTX-B) to neurotoxin receptor site 2 and Centruroides suffusus suffusus beta-scorpion toxin (CsTx II) to site 4 on sodium channels. These results support the proposal that PbTx-2 and related toxins act at a new receptor site (site 5) that has not been previously analyzed in binding experiments. Half-maximal effects of PbTx-2 were observed in the range of 20-50 nM PbTx-2. The enhancement of BTX-B binding was reduced by depolarization. Saturating concentrations of PbTx-2 reduced KD values for binding of BTX-B and CsTx-II 2.9-fold and 2.6-fold, respectively. The effects of PbTx-2 and LqTx in enhancing BTX-B binding were synergistic. A model involving both preferential binding of BTX-B, PbTx-2, LqTx, and CsTx II to active states of sodium channels and allosteric interactions among the four receptor sites at which these toxins act accommodates these and previous results.

  10. A comparative study of an intensive malolactic transformation of cider using Lactobacillus brevis and Oenococcus oeni in a membrane bioreactor.

    PubMed

    Jung, I S; Lovitt, R W

    2010-07-01

    The aim of this study was to investigate the secondary fermentation of alcoholic green cider by Lactobacillus brevis and Oenococcus oeni in a membrane bioreactor so as to compare the performance of the two organisms to rapidly carry out the malolactic fermentation (MLF), an important step in reducing acidity and enhancing the flavor characteristics of the beverages. First, the growth of both organisms was intensified by using perfusion culture in a membrane bioreactor (MBR). O. oeni and L. brevis were grown up to 12.8 g dry cell weight (DCW) l(-1) and 15.5 g DCW l(-1) in the MBR. Secondly, the resultant cells were then used for the malolactic transformation of green cider in the MBR. The influences of the residence time in the MBR and the ethanol concentration of the green cider on the organic acid transformation were investigated. Both organisms showed a good tolerance against the acidic conditions (pH 3.0-4.0) and ethanol (90 g l(-1)). Good levels of malate removal in the MBR were achieved by both organisms but O. oeni was more tolerant to high ethanol concentrations and was capable of growth and malate removal in 130 g ethanol l(-1) green cider. L. brevis malate removal was significantly inhibited above 110 g ethanol l(-1). The MBR allowed the development of high concentrations of active cells capable of rapid MLF and could be achieved over a prolonged period and over a wide range of conditions thus allowing the control of malate transformation rate. Organism selection for the transformation will be governed by the desired beverage characteristics. There is considerable scope to optimize the process further both with the choice of organisms and the design and operation of the reactor. Rapid beverage maturation on a commercial scale may be possible using MBR and pure cultures of MLF lactic acid bacteria.

  11. ATP-dependent phosphorylation of serine-46 in the phosphocarrier protein HPr regulates lactose/H+ symport in Lactobacillus brevis.

    PubMed Central

    Ye, J J; Reizer, J; Cui, X; Saier, M H

    1994-01-01

    Lactobacillus brevis takes up lactose and the nonmetabolizable lactose analogue thiomethyl beta-galactoside (TMG) by a permease-catalyzed lactose/H+ symport mechanism. Earlier studies have shown that TMG, previously accumulated in L. brevis cells, rapidly effluxes from the cells upon addition of glucose, and that glucose inhibits further uptake of TMG. We have developed a vesicular system to analyze this regulatory mechanism and have used electroporation to shock proteins and membrane-impermeant metabolites into the vesicles. Uptake of TMG was dependent on an energy source, effectively provided by intravesicular ATP or extravesicular arginine. TMG uptake into these vesicles was not inhibited, and preaccumulated TMG did not efflux from them upon addition of glucose. Intravesicular but not extravesicular wild-type phosphocarrier protein HPr of Bacillus subtilis restored regulation. Glucose could be replaced by intravesicular (but not extravesicular) fructose 1,6-bisphosphate, gluconate 6-phosphate, or 2-phosphoglycerate, but not by other phosphorylated metabolites, in agreement with the allosteric activating effects of these compounds on HPr(Ser) kinase measured in vitro. Intravesicular serine-46-->alanine mutant HPr cold not promote regulation of lactose permease activity when electroporated into the vesicles with or without glucose or the various phosphorylated metabolites, but the serine-46-->aspartate mutant HPr promoted regulation, even in the absence of glucose or a metabolite. HPr(Ser-P) appears to convert the lactose/H+ symporter into a sugar uniporter. These results establish that HPr serine phosphorylation by the ATP-dependent metabolite-activated HPr kinase regulates lactose permease activity in L. brevis. A direct allosteric mechanism is proposed. Images PMID:8159711

  12. Genes Involved in Control of Galactose Uptake in Lactobacillus brevis and Reconstitution of the Regulatory System in Bacillus subtilis

    PubMed Central

    Djordjevic, Gordana M.; Tchieu, Jason H.; Saier, Milton H.

    2001-01-01

    The heterofermentative lactic acid bacterium Lactobacillus brevis transports galactose and the nonmetabolizable galactose analogue thiomethyl-β-galactoside (TMG) by a permease-catalyzed sugar:H+ symport mechanism. Addition of glucose to L. brevis cells loaded with [14C]TMG promotes efflux and prevents accumulation of the galactoside, probably by converting the proton symporter into a uniporter. Such a process manifests itself physiologically in phenomena termed inducer expulsion and exclusion. Previous evidence suggested a direct allosteric mechanism whereby the phosphocarrier protein, HPr, phosphorylated at serine-46 [HPr(Ser-P)], binds to the galactose:H+ symporter to uncouple sugar transport from proton symport. To elucidate the molecular mechanism of inducer control in L. brevis, we have cloned the genes encoding the HPr(Ser) kinase, HPr, enzyme I, and the galactose:H+ symporter. The sequences of these genes were determined, and the relevant phylogenetic trees are presented. Mutant HPr derivatives in which the regulatory serine was changed to either alanine or aspartate were constructed. The cloned galP gene was integrated into the chromosome of Bacillus subtilis, and synthesis of the mutant HPr proteins in this organism was shown to promote regulation of GalP, as expected for a direct allosteric mechanism. We have thus reconstituted inducer control in an organism that does not otherwise exhibit this phenomenon. These results are consistent with the conclusion that inducer exclusion and expulsion in L. brevis operates via a multicomponent signal transduction mechanism wherein the presence of glycolytic intermediates such as fructose 1,6-bisphosphate (the intracellular effector), derived from exogenous glucose (the extracellular effector), activates HPr(Ser) kinase (the sensor) to phosphorylate HPr on Ser-46 (the messenger), which binds to the galactose:H+ symporter (the target), resulting in uncoupling of sugar transport from proton symport (the response

  13. Induction of Red Color Formation in Cabbage Juice by Lactobacillus brevis and Its Relationship to Pink Sauerkraut1

    PubMed Central

    Stamer, J. R.; Hrazdina, G.; Stoyla, B. O.

    1973-01-01

    Membrane-filtered cabbage juice, when fermented by Lactobacillus brevis under conditions of controlled pH, frequently produced a water-soluble red pigment. The pigment, presumably responsible for imparting a highly objectionable discoloration to sauerkraut, was formed during the post logarithmic phase of growth. Color development is pH dependent (5.2 to 6.3) and can be suppressed by chemical reductants or anaerobic conditions of growth. The compound responsible for discoloration was purified and partially characterized. PMID:16349964

  14. Morphostructural investigation of the female reproductive system and molecular evidence for Wolbachia in Balclutha brevis Lindberg 1954 (Hemiptera, Cicadellidae).

    PubMed

    Pappalardo, A M; D'Urso, V; Viscuso, R; Ferrito, V; Giunta, M C; Cupani, S; Vitale, D G M

    2016-02-01

    Balclutha brevis Lindberg 1954 (Homoptera, Cicadellidae) is an allochthonous species that is rapidly spreading in Sicily and in mainland Europe due to the wide spread of its host plant and therefore could also compete with populations of native species. Considering these ecological implications, based on the lacking ultrastructural data about the reproductive systems of the Auchenorrhyncha and since previous investigations on the male reproductive system of B. brevis have shown some interesting features, we carried out morphostructural investigations on the female reproductive system of this alien leafhopper. Moreover, given the high interest in literature on Wolbachia entomoparasite and based on our previous studies, we provided a contribution to further investigations in applied sciences. For this aim we performed a molecular analysis on males and females of B. brevis to detect the possible presence of strains of the bacterium known to alter host reproductive biology. The female reproductive system has a morphological organization comparable to the general anatomical features of most of the Auchenorrhyncha species; however, comparing our data with the literature, some considerations are discussed. As for the histological and ultrastructural investigations, our results show a secretory activity of the various examined structures. In the spermatheca of B. brevis, in particular, the secretory activity is more marked in the sac-shaped tract, where histochemical investigations showed a lipid component of the secretion; possible origin of this component is discussed. Moreover, mainly free spermatozoa are found in the sac-shaped tract of the spermatheca and in the common oviduct. As for the latter, an interesting findings is the lack of cuticular intima on the epithelial surface of the common oviduct; furthermore, the observed features and the literature in this regards led us to review the significance of the structure called as spermatheca. The molecular screening

  15. Magnetic resonance histology: in situ single cell imaging of receptor cells in an invertebrate (Lolliguncula brevis, Cephalopoda) sense organ.

    PubMed

    Gozansky, Elliott K; Ezell, Edward L; Budelmann, Bernd U; Quast, Michael J

    2003-11-01

    Utilizing contrast-enhanced MR histology, individual cell bodies were identified in situ and compared one-to-one with conventional histology. The squid Lolliguncula brevis served as a model where the receptor cells of the proprioceptive neck receptor organ were labeled with paramagnetic cobalt(II) ions by conventional cobalt iontophoresis. Stimulated echo images were obtained using a 9.4 T magnet and followed by conventional histologic treatment and light microscopy. Images obtained from both these techniques match well and validate MR histology.

  16. Efficient synthesis and secretion of a thermophilic alpha-amylase by protein-producing Bacillus brevis 47 carrying the Bacillus stearothermophilus amylase gene.

    PubMed Central

    Tsukagoshi, N; Iritani, S; Sasaki, T; Takemura, T; Ihara, H; Idota, Y; Yamagata, H; Udaka, S

    1985-01-01

    Bacillus subtilis and Bacillus brevis 47-5, carrying the Bacillus stearothermophilus alpha-amylase gene on pUB110 (pBAM101), synthesized the same alpha-amylase as the donor strain as determined by the enzyme's thermal stability and NH2-terminal amino acid sequence. Regardless of the host, the 34-amino acid signal peptide of the enzyme was processed at exactly the same site between two alanine residues. B. brevis 47-5(pBAM101) secreted the enzyme most efficiently of the hosts examined, 100, 15, and 5 times more than B. stearothermophilus, Escherichia coli HB101(pH1301), and B. subtilis 1A289(pBAM101), respectively. The efficient secretion of the enzyme in B. brevis 47-5(pBAM101) was suggested to be due to the unique properties of the cell wall of this organism. Images PMID:2999073

  17. Impact of Lactic Acid and Hydrogen Ion on the Simultaneous Fermentation of Glucose and Xylose by the Carbon Catabolite Derepressed Lactobacillus brevis ATCC 14869.

    PubMed

    Jeong, Kyung Hun; Israr, Beenish; Shoemaker, Sharon P; Mills, David A; Kim, Jaehan

    2016-07-28

    Lactobacillus brevis ATCC 14869 exhibited a carbon catabolite de-repressed (CCR) phenotype which has ability to consume fermentable sugar simultaneously with glucose. To evaluate this unusual phenotype under harsh conditions during fermentation, the effect of lactic acid and hydrogen ion concentrations on L. brevis ATCC 14869 were examined. Kinetic equations describing the relationship between specific cell growth rate and lactic acid or hydrogen ion concentration has been reduced. The change of substrate utilization and product formation according to lactic acid and hydrogen ion concentration in the media were quantitatively described. Moreover; utilization of other compounds were also observed along with hydrogen ion and lactic acid concentration simultaneously. It has been found that substrate preference changes significantly regarding to utilization of compounds in media. That could result into formation of two-carbon products. In particular, acetic acid present in the media as sodium acetate were consumed by L. brevis ATCC 14869 under extreme pH of both acid and alkaline conditions.

  18. Influence of GABA and GABA-producing Lactobacillus brevis DPC 6108 on the development of diabetes in a streptozotocin rat model.

    PubMed

    Marques, T M; Patterson, E; Wall, R; O'Sullivan, O; Fitzgerald, G F; Cotter, P D; Dinan, T G; Cryan, J F; Ross, R P; Stanton, C

    2016-06-01

    The aim of this study was to investigate if dietary administration of γ-aminobutyric acid (GABA)-producing Lactobacillus brevis DPC 6108 and pure GABA exert protective effects against the development of diabetes in streptozotocin (STZ)-induced diabetic Sprague Dawley rats. In a first experiment, healthy rats were divided in 3 groups (n=10/group) receiving placebo, 2.6 mg/kg body weight (bw) pure GABA or L. brevis DPC 6108 (~10(9)microorganisms). In a second experiment, rats (n=15/group) were randomised to five groups and four of these received an injection of STZ to induce type 1 diabetes. Diabetic and non-diabetic controls received placebo [4% (w/v) yeast extract in dH2O], while the other three diabetic groups received one of the following dietary supplements: 2.6 mg/kg bw GABA (low GABA), 200 mg/kg bw GABA (high GABA) or ~10(9) L. brevis DPC 6108. L. brevis DPC 6108 supplementation was associated with increased serum insulin levels (P<0.05), but did not alter other metabolic markers in healthy rats. Diabetes induced by STZ injection decreased body weight (P<0.05), increased intestinal length (P<0.05) and stimulated water and food intake. Insulin was decreased (P<0.05), whereas glucose was increased (P<0.001) in all diabetic groups, compared with non-diabetic controls. A decrease (P<0.01) in glucose levels was observed in diabetic rats receiving L. brevis DPC 6108, compared with diabetic-controls. Both the composition and diversity of the intestinal microbiota were affected by diabetes. Microbial diversity in diabetic rats supplemented with low GABA was not reduced (P>0.05), compared with non-diabetic controls while all other diabetic groups displayed reduced diversity (P<0.05). L. brevis DPC 6108 attenuated hyperglycaemia induced by diabetes but additional studies are needed to understand the mechanisms involved in this reduction.

  19. Crystal structure of a folate energy-coupling factor transporter from Lactobacillus brevis.

    PubMed

    Xu, Ke; Zhang, Minhua; Zhao, Qin; Yu, Fang; Guo, Hui; Wang, Chengyuan; He, Fangyuan; Ding, Jianping; Zhang, Peng

    2013-05-09

    ATP-binding cassette (ABC) transporters, composed of importers and exporters, form one of the biggest protein superfamilies that transport a variety of substrates across the membrane, powered by ATP hydrolysis. Most ABC transporters are composed of two transmembrane domains and two cytoplasmic nucleotide-binding domains. Also, importers from prokaryotes usually have extra solute-binding proteins in the periplasm that are responsible for the binding of substrates. Structures of importers have been reported that suggested a two-state model for the transport mechanism. Energy-coupling factor (ECF) transporters belong to a new class of ATP-binding cassette importers. Each ECF transporter comprises an energy-coupling module consisting of a transmembrane T protein (EcfT), two nucleotide-binding proteins (EcfA and EcfA'), and another transmembrane substrate-specific binding S protein (EcfS). Despite the similarities with ABC transporters, ECF transporters have different organizational and functional properties. The lack of solute-binding proteins in ECF transporters differentiates them clearly from the canonical ABC importers. Previously reported structures of the EcfS proteins RibU and ThiT clearly demonstrated the binding site of substrate riboflavin and thiamine, respectively. However, the organization of the four different components and the transport mechanism of ECF transporters remain unknown. Here we present the structure of an intact folate ECF transporter from Lactobacillus brevis at a resolution of 3 Å. This structure was captured in an inward-facing, nucleotide-free conformation with no bound substrate. The folate-binding protein FolT is nearly parallel to the membrane and is bound almost entirely by EcfT, which adopts an L shape and connects to EcfA and EcfA' through two coupling helices. Two conserved XRX motifs from the coupling helices of EcfT have a vital role in energy coupling by docking into EcfA-EcfA'. We propose a transport model that involves a

  20. Agroecosystem development of industrial fermentation waste -- characterization of aroma-active compounds from the cultivation medium of Lactobacillus brevis.

    PubMed

    Ono, Toshirou; Usami, Atsushi; Nakaya, Satoshi; Shinpuku, Hideto; Yonejima, Yasunori; Ikeda, Atsushi; Miyazawa, Mitsuo

    2015-01-01

    Volatile oils obtained from both the liquid medium after incubation (MAI) and liquid medium before incubation (MBI) during the cultivation process of Lactobacillus brevis were isolated by hydrodistillation (HD) and analyzed to determine the utility of the liquid waste. The composition of the volatile oils was analyzed by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). In total, 55 and 36 compounds were detected in the volatile oils from MAI (MAI oil) and MBI (MBI oil), respectively. The principle components of MAI oil were N-containing compounds, including 2,3-dimethylpyrazine (16, 37.1 %), methylpyrazine (4, 17.1 %). The important aroma-active compounds in the oils were detected by GC-Olfactometry (GC-O), and their intensity of aroma were measured by aroma extract dilution analysis (AEDA). Expressly, pyrazine compounds were determined as key aroma components; in particular, 2,5-dimethylpyrazine and 2,3-dimethylpyrazine were the most primary aroma-active compound in MAI oil. These results imply that the waste medium after incubation of L. brevis may be utilized as a source of volatile oils.

  1. Cellular fatty acid composition and exopolysaccharide contribute to bile tolerance in Lactobacillus brevis strains isolated from fermented Japanese pickles.

    PubMed

    Suzuki, Shigenori; Kimoto-Nira, Hiromi; Suganuma, Hiroyuki; Suzuki, Chise; Saito, Tadao; Yajima, Nobuhiro

    2014-04-01

    Bile tolerance is a fundamental ability of probiotic bacteria. We examined this property in 56 Lactobacillus brevis strains isolated from Japanese pickles and also evaluated cellular fatty acid composition and cell-bound exopolysaccharide (EPS-b) production. The bile tolerance of these strains was significantly lower in modified de Man - Rogosa - Sharpe (MRS) medium (without Tween 80 or sodium acetate) than in standard MRS medium. Aggregating strains showed significantly higher bile tolerance than nonaggregating strains in MRS medium, but there was no significant difference in the modified MRS media. The relative octadecenoic acid (C18:1) content of the 3 most tolerant aggregating and nonaggregating strains was significantly higher when bile was added to MRS. In MRS without Tween 80, the relative C18:1 content was only marginally affected by addition of bile. In MRS without sodium acetate, only the 3 most tolerant nonaggregating strains increased their relative C18:1 content in the presence of bile. Meanwhile, culture in MRS without sodium acetate reduced EPS-b production in aggregating strains. In conclusion, both EPS-b and cellular fatty acid composition play important roles in bile tolerance of pickle-derived L. brevis.

  2. Detection of acid and hop shock induced responses in beer spoiling Lactobacillus brevis by MALDI-TOF MS.

    PubMed

    Schurr, Benjamin C; Behr, Jürgen; Vogel, Rudi F

    2015-04-01

    Due to the harsh environment, microorganisms encounter in beer, spoilage bacteria must be able to customise their metabolism and physiology in an order to master various kinds of perturbations. Proteomic approaches have been used to examine differences between various beer spoilage bacteria and between different stress conditions, such as acid and hop (Humulus lupulus) stress. However, these investigations cannot detect changes in low molecular weight (lmw) proteins (<150 amino acids). Therefore, for the first time, we herein present data from a proteomic study of lmw proteins for two Lactobacillus (L.) brevis strains exposed to acid stress or, respectively, two different qualities of hop induced stress. We used MALDI-TOF MS as analytical tool for the detection of lmw stress response proteins due to its high sensitivity and low throughput times. Comparing a hop-sensitive and a hop-tolerant strain, detection of the fatty acid biosynthesis-associated acyl carrier protein varied between different stress conditions and incubation times. The findings coincide with previous studies of our group regarding the fatty acid cell membrane composition of beer spoiling L. brevis. It is demonstrated that MALDI-TOF MS is a fast tool to detect and characterise stress situations in beer spoiling bacteria along the lmw sub-proteome.

  3. Effect of ethanol and low pH on citrulline and ornithine excretion and arc gene expression by strains of Lactobacillus brevis and Pediococcus pentosaceus.

    PubMed

    Araque, Isabel; Bordons, Albert; Reguant, Cristina

    2013-02-01

    The accumulation of citrulline and ornithine in wine or beer as a result of the arginine catabolism of some lactic acid bacteria (LAB) species increases the risk of ethyl carbamate and putrescine formation, respectively. Several LAB species, which are found as spoilage bacteria in alcoholic beverages, have been reported to be arginine degrading. This study evaluates the effect of ethanol content and low pH on the excretion of citrulline and ornithine by two strains belonging to the potential contaminant species Lactobacillus brevis and Pediococcus pentosaceus. In the conditions that most affected cell viability, arginine consumption per cell increased noticeably, indicating that arginine utilization may be a stress responsive mechanism. L. brevis showed a higher accumulation of ornithine in the media than P. pentosaceus. In the presence of ethanol, a higher expression of the arcC gene was found in P. pentosaceus, which resulted in a lower excretion of citrulline and ornithine than in L. brevis. This suggests that L. brevis is more likely to produce these amino acids, which are precursors of ethyl carbamate and putrescine.

  4. Identification of an anaerobically induced phosphoenolpyruvate-dependent fructose-specific phosphotransferase system and evidence for the Embden-Meyerhof glycolytic pathway in the heterofermentative bacterium Lactobacillus brevis.

    PubMed Central

    Saier, M H; Ye, J J; Klinke, S; Nino, E

    1996-01-01

    Heterofermentative gram-positive bacteria are believed to metabolize sugars exclusively via the pentose phosphoketolase pathway following uptake via sugar:cation symport. Here we show that anaerobic growth of one such bacterium, Lactobacillus brevis, in the presence of fructose induces the synthesis of a phosphotransferase system and glycolytic enzymes that allow fructose to be metabolized via the Embden-Meyerhof pathway. PMID:8550437

  5. Differentiation of Lactobacillus brevis strains using Matrix-Assisted-Laser-Desorption-Ionization-Time-of-Flight Mass Spectrometry with respect to their beer spoilage potential.

    PubMed

    Kern, Carola C; Vogel, Rudi F; Behr, Jürgen

    2014-06-01

    Lactobacillus (L.) brevis is one of the most frequently encountered bacteria in beer-spoilage incidents. As the species Lactobacillus brevis comprises strains showing varying ability to grow in beer, ranging from growth in low hopped wheat to highly hopped pilsner beer, differentiation and classification of L. brevis with regard to their beer-spoiling ability is of vital interest for the brewing industry. Matrix-Assisted-Laser-Desorption-Ionization-Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) has been shown as a powerful tool for species and sub-species differentiation of bacterial isolates and is increasingly used for strain-level differentiation. Seventeen L. brevis strains, representative of different spoilage types, were characterized according to their tolerance to iso-alpha-acids and their growth in wheat-, lager- and pilsner beer. MALDI-TOF MS spectra were acquired to perform strain-level identification, cluster analysis and biomarker detection. Strain-level identification was achieved in 90% out of 204 spectra. Misidentification occurred nearly exclusively among strains belonging to the same spoilage type. Though spectra of strongly beer-spoiling strains showed remarkable similarity, no decisive single markers were detected to be present in all strains of one group. However, MALDI-TOF MS spectra can be reliably assigned to the corresponding strain and thus allow to track single strains and connect them to their physiological properties.

  6. Cooperative binding of lactose and the phosphorylated phosphocarrier protein HPr(Ser-P) to the lactose/H+ symport permease of Lactobacillus brevis.

    PubMed Central

    Ye, J J; Saier, M H

    1995-01-01

    Lactobacillus brevis accumulates lactose and nonmetabolizable lactose analogues via sugar/H+ symport, but addition of glucose to the extracellular medium results in rapid efflux of the free sugar from the cells due to the uncoupling of sugar transport from proton transport. By using vesicles of L. brevis cells, we recently showed that these regulatory/effects could be attributed to the metabolite-activated ATP-dependent protein kinase-catalyzed phosphorylation of serine-46 in the phosphocarrier protein HPr [HPr(Ser-P)] of the phosphotransferase system and that a mutant form of HPr with the serine-46-->aspartate replacement ([S46D]HPr) is apparently locked in the seryl phosphorylated conformation. We here demonstrate that [S46D]HPr binds directly to inside-out membrane vesicles of L. brevis that contain the lactose permease. Sugar substrates of the permease markedly and specifically stimulate binding of [S46D]HPr to the membranes while certain transport inhibitors such as N-ethylmaleimide block binding. The pH dependency for binding follows that for transport. Wild-type HPr and the [S46A]HPr mutant protein did not appreciably compete with [S46D]HPr for binding to the permease. These results provide evidence for the direct interaction of HPr(Ser-P) with an allosteric site on the lactose/proton symporter of L. brevis for the purpose of regulating sugar accumulation in response to the metabolic needs of the cell. PMID:7831302

  7. The Effect Of Peroneus Brevis Tendon Anatomy On Stability Of Fractures At The Fifth Metatarsal Base

    PubMed Central

    Farrow, Lutul D.; Morris, Parisa M.; Francois, Annie G.; Marcus, Randall E.

    2014-01-01

    Objectives: Fractures of the fifth metatarsal base are not uncommon. Both fracture management and outcomes can differ greatly depending on fracture location. The purpose of the present study is to evaluate the influence of the peroneus brevis (PB) tendon on proximal fifth metatarsal fracture stability. We hypothesize that proximal fifth metatarsal fractures distal to the PB tendon footprint are inherently less stable than more proximal fractures. Methods: We utilized 5 matched pairs of fresh-frozen cadaveric specimens. We carefully exposed the 5th metatarsal and PB tendon. We measured the length of the PB insertion at the base of the fifth metatarsal with calipers. The PB and Achilles tendons were then whip-stitched proximally to facilitate loading. A custom leg holder was fabricated to allow loading and fluoroscopic evaluation. Two conditions were utilized for biomechanical testing; (1) a simulated fracture distal to the PB insertion (Jones equivalent) and (2) a simulated fracture within the footprint of the PB insertion (avulsion equivalent). All fractures were carefully created with a narrow osteotome. Following fracture creation, the plantar flexed foot was statically loaded through the Achilles and PB tendons. Oblique images with and without loading and digital measurements were performed to evaluate for fracture separation. We utilized a paired student T test and intraclass correlation coefficient (ICC) for all statistical analysis. Results: The average length of the PB footprint was 15.2 mm. Compared to fractures within the PB footprint, fractures distal to the PB tendon insertion demonstrated greater fracture widening following loading of the PB tendon. Fractures within the PB footprint widened 0.4 mm on loading (Figure 1A to 1B) compared to 1.1 mm of widening in the fractures distal to the PB insertion (Figure 1C to 1D). This difference was significant (p = 0.02). Intraobserver reliability for all radiographic measurements showed substantial agreement

  8. Imaging of Lactobacillus brevis single cells and microcolonies without a microscope by an ultrasensitive chemiluminescent enzyme immunoassay with a photon-counting television camera.

    PubMed Central

    Yasui, T; Yoda, K

    1997-01-01

    An ultrasensitive chemiluminescent enzyme immunoassay (CLEIA) was developed for the rapid detection and quantification of Lactobacillus brevis contaminants in beer and pitching yeast (Saccharomyces cerevisiae slurry collected for reinoculation). L. brevis cells trapped on a 47-mm nucleopore membrane (0.4-micron pore size) were reacted with a peroxidase-labelled Lactobacillus group E antibody and then subjected to an enhanced CLEIA analysis with 4-iodophenol as the enhancer. The combination of a nucleopore membrane with low background characteristics that enables the antigen-antibody reaction to proceed through the pores of the membrane and a labelled antibody prepared by the maleimide hinge method with minimal nonspecific binding characteristics was essential to minimize background in the detection of single cells. An ultrahigh sensitive charge-coupled device (CCD) camera equipped with a fiber optics image intensifier permitted the imaging of single cells. A clear correlation existed between the number of luminescent spots observed and the plate count [y (CLEIA) = 0.990x (plate count) + 15.9, where n = 7, r = 0.993, and P < 0.001]. Microscopic observation confirmed that the luminescent spots were produced by single cells. This assay could be used to detect approximately 20 L. brevis cells in 633 ml of beer within 4 h. Our ultrasensitive CLEIA could also be used to detect microcolonies approximately 20 microns in diameter which had formed on a membrane after 15 to 18 h of incubation. This method, which we called the microcolony immunoluminescence (MIL) method, increased the signal-to-noise ratio dramatically. The MIL method could be used to detect a 10(0) level of L. brevis contamination in 633 ml of beer and a 1/10(8) level of L. brevis contamination in pitching yeast within 1 day (15 to 18 h to form microcolonies and 2 h for CLEIA). PMID:9361439

  9. Selenium nanoparticle-enriched Lactobacillus brevis causes more efficient immune responses in vivo and reduces the liver metastasis in metastatic form of mouse breast cancer

    PubMed Central

    2013-01-01

    Background and the purpose of the study Selenium enriched Lactobacillus has been reported as an immunostimulatory agent which can be used to increase the life span of cancer bearing animals. Lactic acid bacteria can reduce selenium ions to elemental selenium nanoparticles (SeNPs) and deposit them in intracellular spaces. In this strategy two known immunostimulators, lactic acid bacteria (LAB) and SeNPs, are concomitantly administered for enhancing of immune responses in cancer bearing mice. Methods Forty five female inbred BALB/c mice were divided into three groups of tests and control, each containing 15 mice. Test mice were orally administered with SeNP-enriched Lactobacillus brevis or Lactobacillus brevis alone for 3 weeks before tumor induction. After that the administration was followed in three cycles of seven days on/three days off. Control group received phosphate buffer saline (PBS) at same condition. During the study the tumor growth was monitored using caliper method. At the end of study the spleen cell culture was carried out for both NK cytotoxicity assay and cytokines measurement. Delayed type hypersensitivity (DTH) responses were also assayed after 72h of tumor antigen recall. Serum lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels were measured, the livers of mice were removed and prepared for histopathological analysis. Results High level of IFN-γ and IL-17 besides the significant raised in NK cytotoxicity and DTH responses were observed in SeNP-enriched L. brevis administered mice and the extended life span and decrease in the tumor metastasis to liver were also recorded in this group compared to the control mice or L.brevis alone administered mice. Conclusion Our results suggested that the better prognosis could be achieved by oral administration of SeNP-enriched L. brevis in highly metastatic breast cancer mice model. PMID:23631392

  10. Isolation and basic characterization of a β-glucosidase from a strain of Lactobacillus brevis isolated from a malolactic starter culture

    PubMed Central

    Michlmayr, H.; Schümann, C.; da Silva, N.M. Barreira Braz; Kulbe, K.D.; del Hierro, A.M.

    2011-01-01

    Aims To study glycosidase activities of a Lactobacillus brevis strain and to isolate an intracellular β-glucosidase from this strain. Methods and Results Lactic acid bacteria isolated from a commercially available starter culture preparation for MLF were tested for β-glycosidase activities. A strain of L .brevis showing high intracellular β-d-glucosidase, β-d-xylosidase and α-l-arabinosidase activities was selected for purification and characterization of its β-glucosidase. The pure glucosidase from L. brevis has also side activites of xylosidase, arabinosidase and cellobiosidase. It is a homo-tetramer of 330 kDa and has an isoelectric point at pH 3.5.The Km for p-nitrophenyl-β-d-glucopyranoside and p-nitrophenyl-β-d-xylopyranoside is 0.22 mM and 1.14 mM, respectively. The β-glucosidase activity was strongly inhibited by gluconic acid δ-lactone, partially by glucose and gluconate, but not by fructose. Ethanol and methanol were found to increase the activity up to two fold. The free enzyme was stable at pH 7.0 (t1/2 = 50 d) but not at pH 4.0 (t1/2 = 4 d). Conclusions The β-glucosidase from L. brevis is widely different to that characterized from Lactobacillus casei (Coulon et al. 1998) and Lactobacillus plantarum (Sestelo et al. 2004). The high tolerance to fructose and ethanol, the low inhibitory effect of glucose on the enzyme activity and the good long-term stability could be of great interest for the release of aroma compounds during winemaking. Significance and Impact of the study Although the release of aroma compounds by LAB has been demonstrated by several authors, little information exists on the responsible enzymes. This study contains the first characterization of an intracellular β-glucosidase isolated from a wine related strain of L. brevis. PMID:19702863

  11. Imaging of Lactobacillus brevis single cells and microcolonies without a microscope by an ultrasensitive chemiluminescent enzyme immunoassay with a photon-counting television camera.

    PubMed

    Yasui, T; Yoda, K

    1997-11-01

    An ultrasensitive chemiluminescent enzyme immunoassay (CLEIA) was developed for the rapid detection and quantification of Lactobacillus brevis contaminants in beer and pitching yeast (Saccharomyces cerevisiae slurry collected for reinoculation). L. brevis cells trapped on a 47-mm nucleopore membrane (0.4-micron pore size) were reacted with a peroxidase-labelled Lactobacillus group E antibody and then subjected to an enhanced CLEIA analysis with 4-iodophenol as the enhancer. The combination of a nucleopore membrane with low background characteristics that enables the antigen-antibody reaction to proceed through the pores of the membrane and a labelled antibody prepared by the maleimide hinge method with minimal nonspecific binding characteristics was essential to minimize background in the detection of single cells. An ultrahigh sensitive charge-coupled device (CCD) camera equipped with a fiber optics image intensifier permitted the imaging of single cells. A clear correlation existed between the number of luminescent spots observed and the plate count [y (CLEIA) = 0.990x (plate count) + 15.9, where n = 7, r = 0.993, and P < 0.001]. Microscopic observation confirmed that the luminescent spots were produced by single cells. This assay could be used to detect approximately 20 L. brevis cells in 633 ml of beer within 4 h. Our ultrasensitive CLEIA could also be used to detect microcolonies approximately 20 microns in diameter which had formed on a membrane after 15 to 18 h of incubation. This method, which we called the microcolony immunoluminescence (MIL) method, increased the signal-to-noise ratio dramatically. The MIL method could be used to detect a 10(0) level of L. brevis contamination in 633 ml of beer and a 1/10(8) level of L. brevis contamination in pitching yeast within 1 day (15 to 18 h to form microcolonies and 2 h for CLEIA).

  12. Oral administration of heat-killed Lactobacillus brevis SBC8803 ameliorates the development of dermatitis and inhibits immunoglobulin E production in atopic dermatitis model NC/Nga mice.

    PubMed

    Segawa, Shuichi; Hayashi, Atsushi; Nakakita, Yasukazu; Kaneda, Hirotaka; Watari, Junji; Yasui, Hisako

    2008-05-01

    We have previously shown that the oral administration of heat-killed Lactobacillus brevis (L. brevis) SBC8803 strain inhibits IgE production in ovalbumin (OVA)-sensitized BALB/c mice through improvement of the type-1 helper T (Th1)/Th2 balance toward Th1 dominance. Atopic dermatitis is one of the most common skin diseases and is frequently associated with elevated immunoglobulin E (IgE) antibodies against many kinds of allergens. In this study, we investigated the inhibitory effect of oral administration of L. brevis SBC8803 on the development of dermatitis and IgE elevation using the NC/Nga atopic dermatitis model mice. Male 8-week-old NC/Nga mice were sensitized by the topical application of picryl chloride to foot pads and shaved abdomen. These mice were boosted with picryl chloride by topical application onto the ears once a week for 9 weeks. The mice (n=10 per group) were fed a diet containing 0%, 0.05% or 0.5% of heat-killed L. brevis SBC8803 from 2 weeks before the first sensitization to the end of the study. Total IgE concentration in serum, clinical score, and ear thickness were periodically examined throughout the study. Finally, cytokine (interleukin (IL)-4, IL-5, IL-6, IL-10, IL-12, IFN-gamma and transforming growth factor (TGF)-beta) productions from splenocytes and Peyer's patch (PP) cells of mice were measured. Oral administration of L. brevis SBC8803 significantly inhibited IgE production and ear swelling, and suppressed the development of dermatitis in a dose-dependent manner. Immunosuppressive cytokines such as IL-10 and TGF-beta production from PP cells significantly increased in the 0.5% group compared to the control group although Th1-type and Th2-type cytokines production was not affected.

  13. Lactobacillus brevis strain 1E1 administered to piglets through milk supplementation prior to weaning maintains intestinal integrity after the weaning event.

    PubMed

    Gebert, S; Davis, E; Rehberger, T; Maxwell, C V

    2011-03-01

    Early colonisation in the gastrointestinal tract by commensal microbes influences the progressive development and maturity of digestive and immune system functionality in the neonate. Application of strategically selected direct-fed microbials to neonatal pigs may provide an opportunity to dictate a portion of the intestinal microbial community and exert a beneficial influence on these developmental processes. Experiments were conducted to determine the effects of early administration of Lactobacillus brevis strain 1E1 to neonatal piglets (n=224) via a milk supplement system on gastrointestinal microbial counts, villous architecture, and immune cell phenotypes during the lactation phase and after weaning. Pigs administered the direct-fed microbial had lower Escherichia coli counts in the jejunum and ileum (P<0.05), and lower coliform counts in the jejunum compared to unsupplemented pigs (P<0.05). The villous height:crypt depth ratio was greater in the ileum at 9 days of age when pigs were provided L. brevis 1E1 compared to unsupplemented pigs (P<0.05), as well as in the duodenum of pigs supplemented with L. brevis 1E1 at 22 days of age (P<0.05). The number of leukocytes expressing CD2 (P<0.05), CD4 (P=0.07) and MHC-II (P=0.07) was lower in the jejunum of pigs administered L. brevis 1E1 compared to unsupplemented pigs, however direct-fed microbial treatment had no effect on the number of leukocytes expressing CD8, CD25 or SWC3. These data demonstrate that early colonisation of the porcine gastrointestinal tract with L. brevis strain 1E1 during the lactation phase influences the progression of intestinal structure, immune system development, and pathogen establishment, indicating a relationship between early microbial colonisation and development of intestinal maturity and integrity.

  14. Variations in abductor pollicis longus and extensor pollicis brevis tendons in the Quervain syndrome: a surgical and anatomical study.

    PubMed

    Kulthanan, Teerawat; Chareonwat, Boonsong

    2007-01-01

    Eighty-two wrists of Thai cadavers and the wrists of 66 patients with de Quervain syndrome were studied, and the variation in the number of tendons and the fibro-osseous tunnel in the first extensor compartment were recorded. The abductor pollicis longus had more than one tendon in 73 of the cadavers (89%) and in 32 of the patients (49%) (p <0.001). The extensor pollicis brevis was a single tendon in 80 (98%) and 62 (94%) of cadavers and patients, respectively. There was division with the septum that made a fibro-osseous tunnel in the first extensor compartment in 30/82 (37%) cadavers and in 38/66 (58%) patients with de Quervain syndrome (p = 0.01). The results indicate that the number of fibro-osseous tunnels and multiple compartments in the first extensor compartment may be associated with a predisposition to de Quervain syndrome.

  15. Organophosphorus hydrolase (OpdB) of Lactobacillus brevis WCP902 from kimchi is able to degrade organophosphorus pesticides.

    PubMed

    Islam, Shah Md Asraful; Math, Renukaradhya K; Cho, Kye Man; Lim, Woo Jin; Hong, Su Young; Kim, Jong Min; Yun, Myoung Geun; Cho, Ji Joong; Yun, Han Dae

    2010-05-12

    Lactobacillus brevis WCP902 that is capable of biodegrading chlorpyrifos was isolated from kimchi. The opdB gene cloned from this strain revealed 825 bp, encoding 274 aa, and an enzyme molecular weight of about 27 kDa. OpdB contains the same Gly-X-Ser-X-Gly motif found in most bacterial and eukaryotic esterase, lipase, and serine hydrolases, yet it is a novel member of the GDSVG family of esterolytic enzymes. Its conserved serine residue, Ser82, is significantly involved with enzyme activity that may have application for removing some pesticides. Optimum organophosphorus hydrolase (OpdB) activity appeared at pH 6.0 and 35 degrees C and during degradation of chlorpyrifos, coumaphos, diazinon, methylparathion, and parathion.

  16. Effects of Phenylglyoxal and N-ethylmaleimide Concentration on Mycophenolic Acid Production by Penicillium brevi-compactum ATCC16024

    PubMed Central

    Ardestani, Fatemeh

    2016-01-01

    Mycophenolic acid is a secondary extracellular metabolite of Penicillium strains with numerous pharmaceutical properties such as antibiotic and immunosuppressive uses. The aim of this work is the survey of the effect of phenylglyoxal and n-ethylmaleimide concentration in culture medium on mycophenolic acid production by Penicillium brevi-compactum ATCC16024 was investigated. Batch submerged fermentation was performed in 250 mL shake flasks at 24 °C and 200 rpm in a rotary shaker for 300 h using a basic culture medium containing different concentrations of phenylglyoxal and n-ethylmaleimide ranged from 0 to 20 mg. L-1. For the basic medium without any amounts of phenylglyoxal and n-ethylmaleimide (control), maximum MPA production, product yield and productivity of process was in order, 1.5042 g. L-1, 20.3 mg. g-1 consumed glucose and 5.37 mg. L-1h-1. Maximum produced MPA of 2.9032 g. L-1, MPA yield of 39.23 mg. g-1 of consumed glucose, productivity of 10.37 mg. L-1 h-1 and total enhancement of 93.11% was obtained when the culture medium was contained 18 mg. L-1 of phenylglyoxal, represented more than 93% raising in compare to control. Maximum MPA concentration, yield and productivity in order was obtained 3.1123 g. L-1, 42.06 mg. g-1 of consumed glucose and 11.11 mg. L-1 h-1, with using 6 mg. L-1 of n-ethylmaleimide. N-ethylmaleimide was caused to 2.138 folds (106.89%) increase in MPA production by P. brevi-compactum ATCC16024. PMID:28243291

  17. A dual role of the transcriptional regulator TstR provides insights into cyanide detoxification in Lactobacillus brevis

    PubMed Central

    Pagliai, Fernando A.; Murdoch, Caitlin C.; Brown, Sara M.; Gonzalez, Claudio F.; Lorca, Graciela L.

    2014-01-01

    Summary In this study we uncover two genes in Lactobacillus brevis ATCC367, tstT and tstR, encoding for a rhodanese and a transcriptional regulator involved in cyanide detoxification. TstT (LVIS_0852) belongs to a new class of thiosulfate:cyanide sulfurtransferases. We found that TstR (LVIS_0853) modulates both the expression and the activity of the downstream-encoded tstT. The TstR binding site was identified at −1 to +33, from tstR transcriptional start site. EMSA revealed that sulfite, a product of the reaction catalyzed by TstT, improved the interaction between TstR:PtstR, while Fe(III) disrupted this interaction. Site-directed mutagenesis in TstR identified M64 as a key residue in sulfite recognition, while residues H136-H139-C167-M171 formed a pocket for ferric iron coordination. In addition to its role as a transcriptional repressor, TstR is also involved in regulating the thiosulfate:cyanide sulfurtransferase activity of TstT. A 3-fold increase in TstT activity was observed in the presence of TstR, which was enhanced by the addition of Fe(III). Overexpression of the tstRT operon was found to increase the cyanide tolerance of L. brevis and Escherichia coli. The protein-protein interaction between TstR and TstT described herein represents a novel mechanism for regulation of enzymatic activity by a transcriptional regulator. PMID:24684290

  18. Effects of probiotic Lactobacillus brevis KB290 on incidence of influenza infection among schoolchildren: an open-label pilot study

    PubMed Central

    Waki, N; Matsumoto, M; Fukui, Y; Suganuma, H

    2014-01-01

    Abstract We investigated the efficacy of dietary consumption of Lactobacillus brevis KB290 (KB290) against influenza in humans by a preliminary intervention study on elementary schoolchildren, using a commercially available probiotic drink. Subjects were divided into Groups A and B, and an open-label, parallel-group trial was conducted in two 8-week periods at a 1-month interval in winter 2013/2014. Group A was provided with a bottle of the test drink containing KB290 (about 6 billion colony-forming units) every school day in the first period and had no treatment in the second period, and vice versa for Group B. Epidemic influenza was not observed during the first period and only two of 1783 subjects were diagnosed. In the second period, the incidence of influenza in Groups A (no treatment) and B (provided the test drink) was 23·9 and 15·7%, respectively, and the difference was statistically significant (P < 0·001). The reduction in the incidence of influenza by KB290 consumption was especially remarkable in unvaccinated individuals. This is believed to be the first study to show a probiotic food reducing the incidence of influenza in schoolchildren, although further studies are needed to confirm the effectiveness of the probiotic strain KB290. Significance and Impact of the Study We demonstrated a reduction in the incidence of influenza in 1089 schoolchildren by continual intake of a probiotic drink containing Lactobacillus brevis KB290 (KB290), isolated from a traditional Japanese pickle ‘Suguki’. The effect was especially evident in subjects not inoculated with influenza vaccine. This is believed to be the first report to show reduced incidence of influenza in schoolchildren taking a probiotic food. Further studies are needed to confirm the effectiveness of the probiotic strain KB290, which may be useful in the development of potential anti-influenza agents derived from common foods. PMID:25294223

  19. Enumeration of Carnobacterium divergens V41, Carnobacterium piscicola V1 and Lactobacillus brevis LB62 by in situ hybridization-flow cytometry.

    PubMed

    Connil, N; Dousset, X; Onno, B; Pilet, M F; Breuil, M F; Montel, M C

    1998-11-01

    The specific detection and enumeration of Lactobacillus brevis LB62, Carnobacterium divergens V14 and Carnobacterium piscicola VI were studied by in situ hybridization-flow cytometry. The method was performed on the exponential growth phase with three probes targeting 16S rRNA labelled with fluorescein isothicyanate (FITC): EUB338 probe universal for Eubacteria, Lb probe specific for Lact. brevis and Cb probe specific for the genus Carnobacterium. EUB338 was used to determine the permeabilization and hybridization conditions for the cells. The Lb probe gave no hybridization signal whereas the Cb probe allowed the detection and quantification by flow cytometry at 520 nm of the two Carnobacterium strains in pure culture or in mixtures with Listeria innocua F.

  20. Enhanced Production of Gamma-Aminobutyric Acid by Optimizing Culture Conditions of Lactobacillus brevis HYE1 Isolated from Kimchi, a Korean Fermented Food.

    PubMed

    Lim, Hee Seon; Cha, In-Tae; Roh, Seong Woon; Shin, Hae-Hun; Seo, Myung-Ji

    2017-03-28

    This study evaluated the effects of culture conditions, including carbon and nitrogen sources, L-monosodium glutamate (MSG), and initial pH, on gamma-aminobutyric acid (GABA) production by Lactobacillus brevis HYE1 isolated from kimchi, a Korean traditional fermented food. L. brevis HYE1 was screened by the production analysis of GABA and genetic analysis of the glutamate decarboxylase gene, resulting in 14.64 mM GABA after 48 h of cultivation in MRS medium containing 1% (w/v) MSG. In order to increase GABA production by L. brevis HYE1, the effects of carbon and nitrogen sources on GABA production were preliminarily investigated via one-factor-at-a-time optimization strategy. As the results, 2% maltose and 3% tryptone were determined to produce 17.93 mM GABA in modified MRS medium with 1% (w/v) MSG. In addition, the optimal MSG concentration and initial pH were determined to be 1% and 5.0, respectively, resulting in production of 18.97 mM GABA. Thereafter, response surface methodology (RSM) was applied to determine the optimal conditions of the above four factors. The results indicate that pH was the most significant factor for GABA production. The optimal culture conditions for maximum GABA production were also determined to be 2.14% (w/v) maltose, 4.01% (w/v) tryptone, 2.38% (w/v) MSG, and an initial pH of 4.74. In these conditions, GABA production by L. brevis HYE1 was predicted to be 21.44 mM using the RSM model. The experiment was performed under these optimized conditions, resulting in GABA production of 18.76 mM. These results show that the predicted and experimental values of GABA production are in good agreement.

  1. Description of a new species of Oligosita Walker (Chalcidoidea: Trichogrammatidae), egg parasitoid of Balclutha brevis Lindberg (Homoptera: Cicadellidae) living on Pennisetum setaceum, from Italy.

    PubMed

    Bella, Salvatore; Cupani, Sebastiano; D'urso, Vera; Laudonia, Stefania; Sinno, Martina; Viggiani, Gennaro

    2015-11-06

    A new species of Oligosita Walker (Chalcidoidea: Trichogrammatidae), O. balcluthae Viggiani et Laudonia n. sp., is described as a parasitoid of the eggs of Balclutha brevis Lindberg (Homoptera: Cicadellidae) associated with crimson fountain grass, Pennisetum setaceum (Poaceae) in Italy. Morphological features and biology of the new species are discussed and illustrated. The 28S-D2 and ITS2 regions were successfully amplified and sequenced.

  2. HPTLC fingerprint profile, in vitro antioxidant and evaluation of antimicrobial compound produced from Brevibacillus brevis-EGS9 against multidrug resistant Staphylococcus aureus.

    PubMed

    Arumugam, T; Senthil Kumar, P; Gopinath, K P

    2017-01-01

    In the present study, in vitro antimicrobial activity of Brevibacillus brevis EGS9 against multi drug resistant Staphylococcus aureus (MDRSA) and to investigate the antimicrobial, antioxidant activity and HPTLC finger print profile of Brevibacillus brevis EGS9. Primary screening was done using by cross streak method against multi drug resistant Staphylococcus aureus. The bioactive metabolites were extracted from Brevibacillus brevis EGS9 using ethyl acetate extraction. Ethyl acetate extract showed significant antimicrobial activity against Escherichia coli (20.2 ± 0.1) mm, Candida albicans (19.2 ± 0.3) mm and Bacillus cereus (18.6 ± 0.2) mm respectively. Forty three UTI bacterial strains were isolated from mid-urine samples of 50 males and 50 females. Escherichia coli were more predominant (48%) followed by Klebsilla pneumonia (29%), Pseudomonas aeruginosa (17%), Staphylococcus aureus (4%) and Enterobacter faecalis (6%). The ethyl acetate extract was examined to evaluate antibacterial properties against isolated UTIs bacterial pathogens. The results were revealed that the maximum zone was measured in Escherichia coli (18.1 ± 0.4) mm and minimum zone of inhibition was shown against Pseudomonas aeruginosa (10.6 ± 0.3) mm. Based on the results obtained, the extract of Brevibacillus brevis EGS9 exhibited dose dependent manner of antioxidant activity. The DPPH scavenging activity of lowest concentration at 25 μg/ml and high concentration at 1000 μg/ml was measured at 2.4% and 39.5% respectively. HPTLC finger print profile was showed the active compounds present in crude extract, which may responsible for the antioxidant prospective. These results showed that, the significant antimicrobial properties against pathogen; this work will be helpful to explore the active compound identification in the field of pharmaceutical research and able to produce new drug molecules against pathogens.

  3. Differentiation of species in the Bacillus brevis group and the Bacillus aneurinolyticus group based on the electrophoretic whole-cell protein pattern.

    PubMed

    Shida, O; Takagi, H; Kadowaki, K; Yano, H; Komagata, K

    1996-07-01

    Ninety strains of eleven Bacillus species in the Bacillus brevis group and the Bacillus aneurinolyticus group were compared with the electrophoretic whole-cell protein pattern. The strains were separated into two clusters at the similarity of 55%. One cluster (cluster 1) was consisted of strains from the B. brevis group, and another cluster (cluster 2) was composed of strains from the B. aneurinolyticus group. The cluster 1 was separated into eight subclusters. Out of eight subclusters, seven subclusters contain strains from B. brevis, B. laterosporus, B. agri, B. reuszeri, B. choshinensis, B. formosus, and B. borstelensis. Another subcluster was further separated into two related clusters, which corresponded to B. centrosporus and B. parabrevis, and they were fused at the similarity of 76%. Cluster 2 was separated into two subclusters, which corresponded to B. aneurinolyticus and B. migulanus. The above eleven species showed characteristic patterns distinct from one another, and this correlated well with the published DNA relatedness data. The comparison of the electrophoretic whole-cell protein pattern proved to be useful for evaluation of taxonomic relationships among these taxa.

  4. Multi-Sensor Approach for the Monitoring of Halitosis Treatment via Lactobacillus brevis (CD2)-Containing Lozenges--A Randomized, Double-Blind Placebo-Controlled Clinical Trial.

    PubMed

    Marchetti, Enrico; Tecco, Simona; Santonico, Marco; Vernile, Chiara; Ciciarelli, Daniele; Tarantino, Ester; Marzo, Giuseppe; Pennazza, Giorgio

    2015-08-10

    The aim of this randomized clinical trial was to evaluate whether a recently described multi-sensor approach called BIONOTE(®) is accurate enough to verify the efficacy of treatment of patients with halitosis. A treatment with Lactobacillus brevis (CD2)-containing lozenges, compared with placebo was tested. The BIONOTE(®) was compared with traditional techniques used to detect halitosis: OralChroma™ and two calibrated odor judges enrolled for the organoleptic assessments. Twenty patients (10 treated and 10 placebo), suffering from active phase halitosis were included in the study. Treatment consisted of Lactobacillus brevis (CD2)-containing lozenges or placebo, 4 tablets/day for 14 days. t0 was before the beginning of the study; t1 was day 7 and t2 was day 14. The effectiveness of treatment was assessed through: (1) Rosenberg score; (2) Winkel tongue coating index (WTCI) anterior and posterior; (2) OralChroma™; (3) the new developed multi-sensor approach, called BIONOTE(®) (test technique). Only the WTCI anterior revealed statistically significant changes between t0 and t2 data (p = 0.014) in the treated group. Except for the WTCI anterior, all diagnostic methods revealed the lack of effectiveness for halitosis of a 14-days treatment with Lactobacillus brevis (CD2)-containing lozenges. The BIONOTE(®) multisensor system seems accurate in addition to OralChroma™ to assess the initial condition of halitosis and its mitigation during treatment.

  5. Molecular Cloning and Functional Expression in Lactobacillus plantarum 80 of xylT, Encoding the d-Xylose–H+ Symporter of Lactobacillus brevis

    PubMed Central

    Chaillou, Stéphane; Bor, Yeou-Cherng; Batt, Carl A.; Postma, Pieter W.; Pouwels, Peter H.

    1998-01-01

    A 3-kb region, located downstream of the Lactobacillus brevis xylA gene (encoding d-xylose isomerase), was cloned in Escherichia coli TG1. The sequence revealed two open reading frames which could code for the d-xylulose kinase gene (xylB) and another gene (xylT) encoding a protein of 457 amino acids with significant similarity to the d-xylose–H+ symporters of E. coli, XylE (57%), and Bacillus megaterium, XylT (58%), to the d-xylose–Na+ symporter of Tetragenococcus halophila, XylE (57%), and to the l-arabinose–H+ symporter of E. coli, AraE (60%). The L. brevis xylABT genes showed an arrangement similar to that of the B. megaterium xylABT operon and the T. halophila xylABE operon. Southern hybridization performed with the Lactobacillus pentosus xylR gene (encoding the d-xylose repressor protein) as a probe revealed the existence of a xylR homologue in L. brevis which is not located with the xyABT locus. The existence of a functional XylR was further suggested by the presence of xylO sequences upstream of xylA and xylT and by the requirement of d-xylose for the induction of d-xylose isomerase, d-xylulose kinase, and d-xylose transport activities in L. brevis. When L. brevis was cultivated in a mixture of d-glucose and d-xylose, the d-xylose isomerase and d-xylulose kinase activities were reduced fourfold and the d-xylose transport activity was reduced by sixfold, suggesting catabolite repression by d-glucose of d-xylose assimilation. The xylT gene was functionally expressed in Lactobacillus plantarum 80, a strain which lacks proton motive force-linked d-xylose transport activity. The role of the XylT protein was confirmed by the accumulation of d-xylose in L. plantarum 80 cells, and this accumulation was dependent on the proton motive force generated by either malolactic fermentation or by the metabolism of d-glucose. The apparent affinity constant of XylT for d-xylose was approximately 215 μM, and the maximal initial velocity of transport was 35 nmol/min per

  6. Effects of oral intake of heat-killed Lactobacillus brevis SBC8803 (SBL88™) on dry skin conditions: A randomized, double-blind, placebo-controlled study.

    PubMed

    Ogawa, Masahiro; Saiki, Asako; Matsui, Yuuta; Tsuchimoto, Norihiko; Nakakita, Yasukazu; Takata, Yoshihiro; Nakamura, Takeshi

    2016-12-01

    Lactobacilli are important in intestinal homeostasis, which involves the regulation of immune function, digestive health, cholesterol absorption and intestinal tumor growth amongst others. Our previous investigations have suggested that oral intake of heat-killed Lactobacillus brevis (L. brevis) SBC8803 (SBL88™) suppresses dermatitis by modulating the immune function in an atopic dermatitis mouse model. The aim of the present study was to investigate the effect of heat-killed L. brevis SBC8803 intake on skin hydration conditions in humans. A randomized, double-blind, placebo-controlled study was conducted with volunteers with slightly higher levels of transepidermal water loss (TEWL) on the forearm. The subjects (126 people aged between 21 and 59 years) were randomly allocated to three groups so that the level of TEWL and the age were distributed equally among the groups. The subjects took placebo or heat-killed L. brevis SBC8803 at a daily dose of 25 or 50 mg for 12 weeks. Following the exclusion of eight subjects for plausible reasons (two withdrawals from the study, two for study violations, one for not meeting exclusion criteria and three due to their physical condition), 118 subjects were subjected to the analysis. The results of the present study revealed that following the analysis of the whole populations, marginal differences were observed in TEWL (for example, suppression of skin water loss) at the neck in the 25 mg/day group at week 8 and at the lower eye region in the 50 mg/day group at week 4 (P=0.05 and 0.09, respectively, compared with the placebo group analyzed by Dunnett's test). A significant increase in corneal hydration was also observed at the neck in the 25 mg/day group at week 12 (P=0.06, as compared with the placebo group as analyzed by Dunnett's test). In the analysis of the subpopulations whose habitual frequency of taking lactic fermentation products was less than once per week, the levels of corneal hydration at the neck (in the 50 mg

  7. Isolation of Three New Surface Layer Protein Genes (slp) from Lactobacillus brevis ATCC 14869 and Characterization of the Change in Their Expression under Aerated and Anaerobic Conditions

    PubMed Central

    Jakava-Viljanen, Miia; Åvall-Jääskeläinen, Silja; Messner, Paul; Sleytr, Uwe B.; Palva, Airi

    2002-01-01

    Two new surface layer (S-layer) proteins (SlpB and SlpD) were characterized, and three slp genes (slpB, slpC, and slpD) were isolated, sequenced, and studied for their expression in Lactobacillus brevis neotype strain ATCC 14869. Under different growth conditions, L. brevis strain 14869 was found to form two colony types, smooth (S) and rough (R), and to express the S-layer proteins differently. Under aerobic conditions R-colony type cells produced SlpB and SlpD proteins, whereas under anaerobic conditions S-colony type cells synthesized essentially only SlpB. Anaerobic and aerated cultivations of ATCC 14869 cells in rich medium also resulted in S-layer protein patterns similar to those of the S- and R-colony type cells, respectively. Electron microscopy suggested the presence of only a single S-layer with an oblique structure on the cells of both colony forms. The slpB and slpC genes were located adjacent to each other, whereas the slpD gene was not closely linked to the slpB-slpC gene region. Northern analyses confirmed that both slpB and slpD formed a monocistronic transcription unit and were effectively expressed, but slpD expression was induced under aerated conditions. slpC was a silent gene under the growth conditions tested. The amino acid contents of all the L. brevis ATCC 14869 S-layer proteins were typical of S-layer proteins, whereas their sequence similarities with other S-layer proteins were negligible. The interspecies identity of the L. brevis S-layer proteins was mainly restricted to the N-terminal regions of those proteins. Furthermore, Northern analyses, expression of a PepI reporter protein under the control of the slpD promoter, and quantitative real-time PCR analysis of slpD expression under aerated and anaerobic conditions suggested that, in L. brevis ATCC 14869, the variation of S-layer protein content involves activation of transcription by a soluble factor rather than DNA rearrangements that are typical for most of the S-layer phase

  8. Effects of oral intake of heat-killed Lactobacillus brevis SBC8803 (SBL88™) on dry skin conditions: A randomized, double-blind, placebo-controlled study

    PubMed Central

    Ogawa, Masahiro; Saiki, Asako; Matsui, Yuuta; Tsuchimoto, Norihiko; Nakakita, Yasukazu; Takata, Yoshihiro; Nakamura, Takeshi

    2016-01-01

    Lactobacilli are important in intestinal homeostasis, which involves the regulation of immune function, digestive health, cholesterol absorption and intestinal tumor growth amongst others. Our previous investigations have suggested that oral intake of heat-killed Lactobacillus brevis (L. brevis) SBC8803 (SBL88™) suppresses dermatitis by modulating the immune function in an atopic dermatitis mouse model. The aim of the present study was to investigate the effect of heat-killed L. brevis SBC8803 intake on skin hydration conditions in humans. A randomized, double-blind, placebo-controlled study was conducted with volunteers with slightly higher levels of transepidermal water loss (TEWL) on the forearm. The subjects (126 people aged between 21 and 59 years) were randomly allocated to three groups so that the level of TEWL and the age were distributed equally among the groups. The subjects took placebo or heat-killed L. brevis SBC8803 at a daily dose of 25 or 50 mg for 12 weeks. Following the exclusion of eight subjects for plausible reasons (two withdrawals from the study, two for study violations, one for not meeting exclusion criteria and three due to their physical condition), 118 subjects were subjected to the analysis. The results of the present study revealed that following the analysis of the whole populations, marginal differences were observed in TEWL (for example, suppression of skin water loss) at the neck in the 25 mg/day group at week 8 and at the lower eye region in the 50 mg/day group at week 4 (P=0.05 and 0.09, respectively, compared with the placebo group analyzed by Dunnett's test). A significant increase in corneal hydration was also observed at the neck in the 25 mg/day group at week 12 (P=0.06, as compared with the placebo group as analyzed by Dunnett's test). In the analysis of the subpopulations whose habitual frequency of taking lactic fermentation products was less than once per week, the levels of corneal hydration at the neck (in the 50 mg

  9. Characterization and Mutational Analysis of a Two-Polypeptide Bacteriocin Produced by Citrus Iyo-Derived Lactobacillus brevis 174A.

    PubMed

    Noda, Masafumi; Miyauchi, Rumi; Danshiitsoodol, Narandalai; Higashikawa, Fumiko; Kumagai, Takanori; Matoba, Yasuyuki; Sugiyama, Masanori

    2015-01-01

    In the present study, we isolated a lactic acid bacterium (LAB) from a citrus iyo fruit and identified it as Lactobacillus brevis. This plant-derived LAB strain, designated 174A, produces bacteriocin consisting of two polypeptides designated brevicin 174A-β and 174A-γ. Although each polypeptide itself displays antibacterial activity, the ability is enhanced 100 fold by mixing both polypeptides at a 1 : 1 ratio. Significantly, brevicin 174A inhibits even the growth of several pathogenic bacteria that are more resistant to a lantibiotic bacteriocin, nisin A, which is commonly utilized as a preservative added to foodstuffs. Structural analysis of the 174A bacteriocin using a program that predicts secondary structure suggests that both component polypeptides have a positively charged N-terminal region, as well as two cysteine residues in both the N- and C-terminals. Judging from a mutational analysis of the antibacterial polypeptides, these unique amino acid sequences of 174A-β might be important for the expression of the synergistic activity that occurs in the presence of the two polypeptides combined.

  10. The serotonin receptor mediates changes in autonomic neurotransmission and gastrointestinal transit induced by heat-killed Lactobacillus brevis SBC8803.

    PubMed

    Horii, Y; Nakakita, Y; Misonou, Y; Nakamura, T; Nagai, K

    2015-01-01

    Lactobacilli exhibit several health benefits in mammals, including humans. Our previous reports established that heat-killed Lactobacillus brevis SBC8803 (SBC8803) increased both efferent gastric vagal nerve activity and afferent intestinal vagal nerve activity in rats. We speculated that this strain could be useful for the treatment of gastrointestinal (GI) disorders. In this study, we examined the effects of SBC8803 on peristalsis and the activity of the efferent celiac vagal nerve innervating the intestine in rats. First, we examined the effects of intraduodenal (ID) administration of SBC8803 on efferent celiac vagal nerve activity (efferent CVNA) in urethane-anesthetised rats using electrophysiological studies. The effects of intravenous injection of the serotonin 5-HT3 receptor antagonist granisetron on changes in efferent CVNA due to ID administration of SBC8803 were also investigated. Finally, the effects of oral gavage of SBC8803 on GI transit were analysed using the charcoal propulsion method in conscious rats treated with or without granisetron. ID administration of SBC8803 increased efferent CVNA. Pretreatment with granisetron eliminated SBC8803-dependent changes in efferent CVNA. Furthermore, oral gavage of SBC8803 significantly accelerated GI transit, while pretreatment with granisetron inhibited GI transit. Our findings suggested that SBC8803 increased efferent CVNA and GI transit of charcoal meal via 5-HT3 receptors. Moreover, SBC8803 enhanced the activity of efferent vagal nerve innervating the intestine and promoted peristalsis via 5-HT3 receptors.

  11. Xylooligosaccharides from hardwood and cereal xylans produced by a thermostable xylanase as carbon sources for Lactobacillus brevis and Bifidobacterium adolescentis.

    PubMed

    Falck, Peter; Precha-Atsawanan, Suthsiri; Grey, Carl; Immerzeel, Peter; Stålbrand, Henrik; Adlercreutz, Patrick; Karlsson, Eva Nordberg

    2013-07-31

    To compare xylans from forestry with agricultural origins, hardwood xylan (birch) and cereal arabinoxylan (rye) were hydrolyzed using two variants of the xylanase RmXyn10A, full-length enzyme and catalytic module only, from Rhodothermus marinus . Cultivations of four selected bacterial species, using the xylooligosaccharide (XOS) containing hydrolysates as carbon source, showed selective growth of Lactobacillus brevis DSMZ 1264 and Bifidobacterium adolescentis ATCC 15703. Both strains were confirmed to utilize the XOS fraction (DP 2-5), whereas putative arabinoxylooligosaccharides from the rye arabinoxylan hydrolysate were utilized by only B. adolescentis. Escherichia coli did not grow, despite its capability to grow on the monosaccharides arabinose and xylose. It was also shown that Pediococcus parvulus strain 2.6 utilized neither xylose nor XOS for growth. In summary, RmXyn10A or its catalytic module proved suitable for high-temperature hydrolysis of hardwood xylan and cereal arabinoxylan, producing XOS that could qualify as prebiotics for use in functional food products.

  12. Different fibre populations distinguished by their calcium transient characteristics in enzymatically dissociated murine flexor digitorum brevis and soleus muscles.

    PubMed

    Calderón, Juan C; Bolaños, Pura; Torres, Sonia H; Rodríguez-Arroyo, Greta; Caputo, Carlo

    2009-01-01

    Enzymatically dissociated flexor digitorum brevis (FDB) and soleus fibres from mouse were used to compare the kinetics of electrically elicited Ca2+ transients of slow and fast skeletal muscle fibres, using the fast Ca2+ dye MagFluo4-AM, at 20-22 degrees C. For FDB two Ca2+ transient morphologies, types I (MT-I, 11 fibres, 19%) and II (MT-II, 47 fibres, 81%), were found, the kinetic parameters (amplitude, rise time, half width, decay time, and time constants of decay) being statistically different. For soleus (n = 20) only MT-I was found, with characteristics similar to MT-I from FDB. Correlations with histochemically determined mATPase, reduced nicotinamide adenine dinucleotide diaphorase and alpha-glycerophosphate dehydrogenase activities, as well as immunostaining and myosin heavy chain electrophoretic analysis of both muscles suggest that signals classified as MT-I may correspond to slow type I and fast IIA fibres while those classified as MT-II may correspond to fast IIX/D fibres. The results point to the importance of Ca2+ signaling for characterization of muscle fibres, but also to its possible role in determining fibre function.

  13. Effect of the Refrigerator Storage Time on the Potency of Botox for Human Extensor Digitorum Brevis Muscle Paralysis

    PubMed Central

    Ahn, Ki Young

    2013-01-01

    Background and Purpose It is recommended that Botox be used within 5 hours of reconstitution, which results in substantial quantities being discarded. This is not only uneconomic, but also inconvenient for treating patients. The aim of this study was to determine the potencies of Botox used within 2 hours of reconstitution with unpreserved saline, the same Botox refrigerated (at +4℃) 72 hours after reconstitution, and during the next 4 consecutive weeks (weeks 1, 2, 3, and 4). This comparison was used to determine the length of refrigeration time during which reconstituted Botox will maintain the same efficacy as freshly reconstituted toxin. Methods Individual paralysis rates in the extensor digitorum brevis (EDB) compound muscle action potential (CMAP) amplitude and area were measured 1 week after injecting fresh reconstituted 2.5 MU of Botox on one side of the foot, and when the same quantity of Botox that had been refrigerated for a designated time (i.e., 72 h, or 1, 2, 3, or 4 weeks) into the other side of the foot. The EDB CMAP amplitude and area at 12 and 16 weeks postinjection were also measured to compare the efficacy durations in all five comparative groups. Results Ninety-four volunteers were divided into five groups according to the refrigerator storage time of the second Botox injection. The paralysis of the EDBs was significant for each injection of Botox, both fresh and refrigerated, with no statistically significant differences between them, regardless of the refrigeration time. There was a tendency toward increased CMAP amplitude and area at 12 or 16 weeks postinjection (p<0.0001). The duration of effective muscle paralysis did not differ significantly throughout the 16-week follow-up period between all five groups. Conclusions The potency of reconstituted Botox is not degraded by subsequent refrigeration for 4 weeks. However, there are definite concerns regarding its sterility, and hence its safety, since multiple withdrawals from the same vial

  14. The structure of Lactobacillus brevis surface layer reassembled on liposomes differs from native structure as revealed by SAXS.

    PubMed

    Kontro, Inkeri; Wiedmer, Susanne K; Hynönen, Ulla; Penttilä, Paavo A; Palva, Airi; Serimaa, Ritva

    2014-08-01

    The reassembly of the S-layer protein SlpA of Lactobacillus brevis ATCC 8287 on positively charged liposomes was studied by small angle X-ray scattering (SAXS) and zeta potential measurements. SlpA was reassembled on unilamellar liposomes consisting of 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-3-trimethylammonium-propane, prepared by extrusion through membranes with pore sizes of 50nm and 100nm. Similarly extruded samples without SlpA were used as a reference. The SlpA-containing samples showed clear diffraction peaks in their SAXS intensities. The lattice constants were calculated from the diffraction pattern and compared to those determined for SlpA on native cell wall fragments. Lattice constants for SlpA reassembled on liposomes (a=9.29nm, b=8.03nm, and γ=84.9°) showed a marked change in the lattice constants b and γ when compared to those determined for SlpA on native cell wall fragments (a=9.41nm, b=6.48nm, and γ=77.0°). The latter are in good agreement with values previously determined by electron microscopy. This indicates that the structure formed by SlpA is stable on the bacterial cell wall, but SlpA reassembles into a different structure on cationic liposomes. From the (10) reflection, the lower limit of crystallite size of SlpA on liposomes was determined to be 92nm, corresponding to approximately ten aligned lattice planes.

  15. Surface Location of Individual Residues of SlpA Provides Insight into the Lactobacillus brevis S-Layer▿

    PubMed Central

    Vilen, Heikki; Hynönen, Ulla; Badelt-Lichtblau, Helga; Ilk, Nicola; Jääskeläinen, Pentti; Torkkeli, Mika; Palva, Airi

    2009-01-01

    Bacterial surface layer (S-layer) proteins are excellent candidates for in vivo and in vitro nanobiotechnological applications because of their ability to self-assemble into two-dimensional lattices that form the outermost layer of many Eubacteria and most Archaea species. Despite this potential, knowledge about their molecular architecture is limited. In this study, we investigated SlpA, the S-layer protein of the potentially probiotic bacterium Lactobacillus brevis ATCC 8287 by cysteine-scanning mutagenesis and chemical modification. We generated a series of 46 mutant proteins by replacing single amino acids with cysteine, which is not present in the wild-type protein. Most of the replaced amino acids were located in the self-assembly domain (residues 179 to 435) that likely faces the outer surface of the lattice. As revealed by electron microscopy, all the mutant proteins were able to form self-assembly products identical to that of the wild type, proving that this replacement does not dramatically alter the protein conformation. The surface accessibility of the sulfhydryl groups introduced was studied with two maleimide-containing marker molecules, TMM(PEG)12 (molecular weight [MW], 2,360) and AlexaFluor488-maleimide (MW = 720), using both monomeric proteins in solution and proteins allowed to self-assemble on cell wall fragments. Using the acquired data and available domain information, we assigned the mutated residues into four groups according to their location in the protein monomer and lattice structure: outer surface of the lattice (9 residues), inner surface of the lattice (9), protein interior (12), and protein-protein interface/pore regions (16). This information is essential, e.g., in the development of therapeutic and other health-related applications of Lactobacillus S-layers. PMID:19304849

  16. A dual role of the transcriptional regulator TstR provides insights into cyanide detoxification in Lactobacillus brevis.

    PubMed

    Pagliai, Fernando A; Murdoch, Caitlin C; Brown, Sara M; Gonzalez, Claudio F; Lorca, Graciela L

    2014-05-01

    In this study we uncover two genes in Lactobacillus brevis ATCC 367, tstT and tstR, encoding for a rhodanese and a transcriptional regulator involved in cyanide detoxification. TstT (LVIS_0852) belongs to a new class of thiosulphate:cyanide sulphurtransferases. We found that TstR (LVIS_0853) modulates both the expression and the activity of the downstream-encoded tstT. The TstR binding site was identified at -1 to +33, from tstR transcriptional start site. EMSA revealed that sulphite, a product of the reaction catalysed by TstT, improved the interaction between TstR:P(tstR), while Fe(III) disrupted this interaction. Site-directed mutagenesis in TstR identified M64 as a key residue in sulphite recognition, while residues H136-H139-C167-M171 formed a pocket for ferric iron co-ordination. In addition to its role as a transcriptional repressor, TstR is also involved in regulating the thiosulphate:cyanide sulphurtransferase activity of TstT. A threefold increase in TstT activity was observed in the presence of TstR, which was enhanced by the addition of Fe(III). Overexpression of the tstRT operon was found to increase the cyanide tolerance of L. brevis and Escherichia coli. The protein-protein interaction between TstR and TstT described herein represents a novel mechanism for regulation of enzymatic activity by a transcriptional regulator.

  17. Cu Nanoparticles Have Different Impacts in Escherichia coli and Lactobacillus brevis than Their Microsized and Ionic Analogues.

    PubMed

    Kaweeteerawat, Chitrada; Chang, Chong Hyun; Roy, Kevin R; Liu, Rong; Li, Ruibin; Toso, Daniel; Fischer, Heidi; Ivask, Angela; Ji, Zhaoxia; Zink, Jeffrey I; Zhou, Z Hong; Chanfreau, Guillaume Francois; Telesca, Donatello; Cohen, Yoram; Holden, Patricia Ann; Nel, Andre E; Godwin, Hilary A

    2015-07-28

    Copper formulations have been used for decades for antimicrobial and antifouling applications. With the development of nanoformulations of copper that are more effective than their ionic and microsized analogues, a key regulatory question is whether these materials should be treated as new or existing materials. To address this issue, here we compare the magnitude and mechanisms of toxicity of a series of Cu species (at concentration ranging from 2 to 250 μg/mL), including nano Cu, nano CuO, nano Cu(OH)2 (CuPro and Kocide), micro Cu, micro CuO, ionic Cu(2+) (CuCl2 and CuSO4) in two species of bacteria (Escherichia coli and Lactobacillus brevis). The primary size of the particles studied ranged from 10 nm to 10 μm. Our results reveal that Cu and CuO nanoparticles (NPs) are more toxic than their microsized counterparts at the same Cu concentration, with toxicities approaching those of the ionic Cu species. Strikingly, these NPs showed distinct differences in their mode of toxicity when compared to the ionic and microsized Cu, highlighting the unique toxicity properties of materials at the nanoscale. In vitro DNA damage assays reveal that both nano Cu and microsized Cu are capable of causing complete degradation of plasmid DNA, but electron tomography results show that only nanoformulations of Cu are internalized as intact intracellular particles. These studies suggest that nano Cu at the concentration of 50 μg/mL may have unique genotoxicity in bacteria compared to ionic and microsized Cu.

  18. Cambial Growth Season of Brevi-Deciduous Brachystegia spiciformis Trees from South Central Africa Restricted to Less than Four Months

    PubMed Central

    Trouet, Valérie; Mukelabai, Mukufute; Verheyden, Anouk; Beeckman, Hans

    2012-01-01

    We investigate cambial growth periodicity in Brachystegia spiciformis, a dominant tree species in the seasonally dry miombo woodland of southern Africa. To better understand how the brevi-deciduous (experiencing a short, drought-induced leaf fall period) leaf phenology of this species can be linked to a distinct period of cambial activity, we applied a bi-weekly pinning to six trees in western Zambia over the course of one year. Our results show that the onset and end of cambial growth was synchronous between trees, but was not concurrent with the onset and end of the rainy season. The relatively short (three to four months maximum) cambial growth season corresponded to the core of the rainy season, when 75% of the annual precipitation fell, and to the period when the trees were at full photosynthetic capacity. Tree-ring studies of this species have found a significant relationship between annual tree growth and precipitation, but we did not observe such a correlation at intra-annual resolution in this study. Furthermore, a substantial rainfall event occurring after the end of the cambial growth season did not induce xylem initiation or false ring formation. Low sample replication should be taken into account when interpreting the results of this study, but our findings can be used to refine the carbon allocation component of process-based terrestrial ecosystem models and can thus contribute to a more detailed estimation of the role of the miombo woodland in the terrestrial carbon cycle. Furthermore, we provide a physiological foundation for the use of Brachystegia spiciformis tree-ring records in paleoclimate research. PMID:23071794

  19. Cambial growth season of brevi-deciduous Brachystegia spiciformis trees from south central Africa restricted to less than four months.

    PubMed

    Trouet, Valérie; Mukelabai, Mukufute; Verheyden, Anouk; Beeckman, Hans

    2012-01-01

    We investigate cambial growth periodicity in Brachystegia spiciformis, a dominant tree species in the seasonally dry miombo woodland of southern Africa. To better understand how the brevi-deciduous (experiencing a short, drought-induced leaf fall period) leaf phenology of this species can be linked to a distinct period of cambial activity, we applied a bi-weekly pinning to six trees in western Zambia over the course of one year. Our results show that the onset and end of cambial growth was synchronous between trees, but was not concurrent with the onset and end of the rainy season. The relatively short (three to four months maximum) cambial growth season corresponded to the core of the rainy season, when 75% of the annual precipitation fell, and to the period when the trees were at full photosynthetic capacity. Tree-ring studies of this species have found a significant relationship between annual tree growth and precipitation, but we did not observe such a correlation at intra-annual resolution in this study. Furthermore, a substantial rainfall event occurring after the end of the cambial growth season did not induce xylem initiation or false ring formation. Low sample replication should be taken into account when interpreting the results of this study, but our findings can be used to refine the carbon allocation component of process-based terrestrial ecosystem models and can thus contribute to a more detailed estimation of the role of the miombo woodland in the terrestrial carbon cycle. Furthermore, we provide a physiological foundation for the use of Brachystegia spiciformis tree-ring records in paleoclimate research.

  20. Attenuating effect of Lactobacillus brevis G101 on the MSG symptom complex in a double-blind, placebo-controlled study

    PubMed Central

    Kim, Dong-Hyun; Choi, Yeji; Park, Sun-Sung; Kim, Se-Young

    2015-01-01

    BACKGROUND/OBJECTIVES Lactobacillus brevis G101 suppresses the absorption of monosodium glutamate (MSG) from the intestine into the blood in mice. Therefore, the attenuating effect of orally administered G101 on monosodium glutamate (MSG) symptom complex was investigated in humans. MATERIALS/METHODS Capsules (300 mg) containing Lactobacillus brevis G101 (1×1010 CFU/individual) or maltodextrin (placebo) was orally administered in 30 respondents with self-recognized monosodium glutamate (MSG) symptom complex for 5 days and the rice with black soybean sauce containing 6 g MSG (RBSM) was ingested 30 min after the final administration. Thereafter, the MSG symptom complex (rated on a 5-point scale: 1, none; 5, strong) was investigated in a double blind placebo controlled study. The intensity of the MSG symptom complex was significantly reduced in respondents of the G101 intake group (2.87 ± 0.73) compared to that in those treated with the placebo (3.63 ± 1.03) (P = 0.0016). Respondents in the placebo group exhibited more of the various major conditions of the MSG symptom complex than in the G101 intake group. Although there was no significant difference in the appearance time of the MSG symptom complex between subjects orally administered G101 and those administered the placebo, its disappearance in < 3 h was observed in 69.9% of subjects in the G101 treatment group and in 38.0% of subjects in the placebo group (P = 0.0841). CONCLUSIONS Oral administration of Lactobacillus brevis G101 may be able to reduce the intensity of the MSG symptom complex. PMID:26634058

  1. Characterization of the Production of Biogenic Amines and Gamma-Aminobutyric Acid in the Soybean Pastes Fermented by Aspergillus oryzae and Lactobacillus brevis.

    PubMed

    Kim, Nam Yeun; Ji, Geun Eog

    2015-04-01

    The production of gamma-aminobutyric acid (GABA) using GABA-producing lactic acid bacteria (LAB) has been considered to be an attractive strategy. However, some LAB may produce biogenic amines (BA), which may be of concern from the safety viewpoint. The aim of the present study was to characterize the production of GABA and BA in the soybean pastes fermented by Aspergillus oryzae (A. oryzae) FMB S46471 and GABA-producing Lactobacillus brevis (L. brevis) GABA 100. After a ripening period of 90 days, the levels of BA (putrescine, cadaverine, histamine, and tyramine) and GABA in the fermented soybean were assessed by highperformance liquid chromatography. The soybean pastes fermented by A. oryzae and L. brevis showed a range of 7,130-11,592 mg/kg for GABA, 178-305 mg/kg for tyramine, 139-163 mg/kg for putrescine, 7.4-10.8 mg/kg for histamine, and 7.1-7.9 mg/kg for cadaverine, whereas the soybean pastes fermented by A. oryzae only showed a range of 30-1,671 mg/kg for GABA, 0.8-189 mg/kg for tyramine, 1.3-85 mg/kg for putrescine, up to 3.6 mg/kg for histamine, and 0.2-2.4 mg/kg for cadaverine. The results showed that the production of GABA was accompanied by the increase in the production of BA, even though the production levels of histamine and cadaverine were very low. This is the first study to simultaneously characterize the production of BA and GABA in GABA-enriched fermented soybean pastes, and warrants further study to minimize the production of BA while optimizing the production of GABA.

  2. Identification and characterization of domains responsible for self-assembly and cell wall binding of the surface layer protein of Lactobacillus brevis ATCC 8287

    PubMed Central

    Åvall-Jääskeläinen, Silja; Hynönen, Ulla; Ilk, Nicola; Pum, Dietmar; Sleytr, Uwe B; Palva, Airi

    2008-01-01

    Background Lactobacillus brevis ATCC 8287 is covered by a regular surface (S-) layer consisting of a 435 amino acid protein SlpA. This protein is completely unrelated in sequence to the previously characterized S-layer proteins of Lactobacillus acidophilus group. Results In this work, the self-assembly and cell wall binding domains of SlpA were characterized. The C-terminal self-assembly domain encompassed residues 179–435 of mature SlpA, as demonstrated by the ability of N-terminally truncated recombinant SlpA to form a periodic structure indistinguishable from that formed by full length SlpA. Furthermore, a trypsin degradation analysis indicated the existence of a protease resistant C-terminal domain of 214 amino acids. By producing a set of C-terminally truncated recombinant SlpA (rSlpA) proteins the cell wall binding region was mapped to the N-terminal part of SlpA, where the first 145 amino acids of mature SlpA alone were sufficient for binding to isolated cell wall fragments of L. brevis ATCC 8287. The binding of full length rSlpA to the cell walls was not affected by the treatment of the walls with 5% trichloroacetic acid (TCA), indicating that cell wall structures other than teichoic acids are involved, a feature not shared by the Lactobacillus acidophilus group S-layer proteins characterized so far. Conserved carbohydrate binding motifs were identified in the positively charged N-terminal regions of six Lactobacillus brevis S-layer proteins. Conclusion This study identifies SlpA as a two-domain protein in which the order of the functional domains is reversed compared to other characterized Lactobacillus S-layer proteins, and emphasizes the diversity of potential cell wall receptors despite similar carbohydrate binding sequence motifs in Lactobacillus S-layer proteins. PMID:18828902

  3. Transcriptome analysis of beer-spoiling Lactobacillus brevis BSO 464 during growth in degassed and gassed beer.

    PubMed

    Bergsveinson, Jordyn; Friesen, Vanessa; Ziola, Barry

    2016-10-17

    Lactobacillus brevis BSO 464 (Lb464) is a beer-spoilage-related (BSR) isolate of interest given its unique physiological attributes; specifically, it is highly hop-tolerant and exhibits very rapid growth in pressurized/gassed beer. RNA sequencing was performed on Lb464 grown in pressurized and non-pressurized beer to determine important genetic mechanisms for growth in these environments. The data generated were compared against data in a previous transcriptional study of another lactic acid bacterium (LAB) during growth in beer, namely, Pediococcus claussenii ATCC BAA-344(T) (Pc344). Results revealed that the most important genetic elements for Lb464 growth in beer are related to biogenic amine metabolism, membrane transport and fortification, nutrient scavenging, and efficient transcriptional regulation. Comparison with the previous transcriptional study of Pc344 indicated that the total coding capacity (plasmid profile and genome size) of a LAB isolate allows for beer-spoilage virulence and adaptation to different beer environments, i.e., the ability to grow in degassed beer (during production) or gassed beer (packaged product). Further, differences in gene expression of Lb464 and Pc344 during mid-exponential growth in beer may dictate how rapidly each isolate exhausts particular carbon sources during. The presence of headspace pressure/dissolved CO2 was found to drive Lb464 transcription during mid-exponential growth in beer towards increasing cell wall and membrane modification, transport, osmoregulation, and DNA metabolism and transposition events. This transcriptional activity resembles transcriptional patterns or signatures observed in a viable, but non-culturable state established by non-related organisms, suggesting that Lb464 overall uses complex cellular regulation to maintain cell division and growth in the stressful beer environment. Additionally, increased expression of several hypothetical proteins, the hop-tolerance gene horC, and DNA repair and

  4. The effect of Lactobacillus brevis KB290 against irritable bowel syndrome: a placebo-controlled double-blind crossover trial

    PubMed Central

    2012-01-01

    Background Irritable bowel syndrome (IBS) is a functional disorder of the digestive tract that causes chronic abdominal symptoms. We evaluated the effects of Lactobacillus brevis KB290 (KB290), which has been demonstrated to be effective at improving bowel movements and the composition of intestinal microflora, on IBS symptoms. Methods We performed a placebo control double-blind cross matched trial. Thirty-five males and females (aged 6 years and above) who had been diagnosed with IBS according to the Rome III criteria were divided into 2 groups, and after a 4-week pre-trial observation period, they were administered test capsules containing KB290 or placebo for 4 weeks (consumption period I). Then, the capsule administration was suspended for 4 weeks in both groups (washout period), before the opposite capsules were administered for a further 4 weeks (consumption period II). Fecal samples were collected on the first day of the pre-consumption observation period, the last day of consumption period I, the last day of the washout period, and the last day of consumption period II. In addition, the subjects’ IBS symptoms and quality of life (QOL) and any adverse events that they experienced were evaluated. Results No significant difference in IBS symptoms was noted among the various periods. However, the mean QOL scores were improved during the test capsule consumption. The frequencies of watery and mushy feces were significantly lower in the test capsule consumption period than during the pre-consumption observation period, and the frequency of abdominal pain was significantly reduced in the test capsule consumption period compared with the other periods. The frequency of the genus Bifidobacterium was significantly higher, and that of the genus Clostridium was significantly lower, after the test capsule consumption than after the placebo consumption. The frequencies of the genera Lactobacillus, Bacteroides, and Enterococcus were also investigated, but no differences

  5. Molecular cloning of the dnaK locus, and purification and characterization of a DnaK protein from Bacillus brevis HPD31.

    PubMed

    Tokunaga, H; Yamakawa, M; Mizukami, M; Takagi, H; Tokunaga, M

    1998-09-08

    Using part of the dnaK gene from Bacillus subtilis as a probe, a 4. 4-kbp SacI-BglII fragment of chromosomal DNA of Bacillus brevis, a protein-hypersecreting bacterium, was cloned. Nucleotide sequencing revealed 3 open reading frames in the order of grpE-dnaK-dnaJ homologues. We purified DnaK protein to homogeneity from B. brevis HPD31 harboring a multi-copy dnaK expression plasmid. Purified DnaK showed ATPase activity which was synergistically stimulated 14-fold by the addition of glutathione S-transferase-DnaJ and glutathione S-transferase-GrpE fusion proteins. DnaK hydrolyzed not only ATP but also CTP, UTP, and GTP at about 40% of the efficiency of ATP. The specific activity of DnaK-ATPase was 7.25x10-3 unit/mg protein (the turnover number against ATP was 0.47 min-1) under our assay conditions. The DnaK dimers dissociated into monomers on addition of ATP, GTP, CTP, UTP and ATPgammaS, but not ADP or AMP. DnaK formed a stable complex with permanently unfolded carboxymethylated alpha-lactalbumin but not with native alpha-lactalbumin, and this complex was dissociated by addition of ATP/Mg. Formation of this complex was inhibited in the presence of inorganic phosphate.

  6. Hop resistance in the beer spoilage bacterium Lactobacillus brevis is mediated by the ATP-binding cassette multidrug transporter HorA.

    PubMed

    Sakamoto, K; Margolles, A; van Veen, H W; Konings, W N

    2001-09-01

    Lactobacillus brevis is a major contaminant of spoiled beer. The organism can grow in beer in spite of the presence of antibacterial hop compounds that give the beer a bitter taste. The hop resistance in L. brevis is, at least in part, dependent on the expression of the horA gene. The deduced amino acid sequence of HorA is 53% identical to that of LmrA, an ATP-binding cassette multidrug transporter in Lactococcus lactis. To study the role of HorA in hop resistance, HorA was functionally expressed in L. lactis as a hexa-histidine-tagged protein using the nisin-controlled gene expression system. HorA expression increased the resistance of L. lactis to hop compounds and cytotoxic drugs. Drug transport studies with L. lactis cells and membrane vesicles and with proteoliposomes containing purified HorA protein identified HorA as a new member of the ABC family of multidrug transporters.

  7. Improvement of mannitol production by Lactobacillus brevis mutant 3-A5 based on dual-stage pH control and fed-batch fermentations.

    PubMed

    Yue, Min; Cao, Hailong; Zhang, Jianping; Li, Shuguang; Meng, Yanyu; Chen, Wei; Huang, Lishuxin; Du, Yuguang

    2013-10-01

    Lactobacillus brevis 3-A5 was isolated and expected to produce mannitol efficiently by regulating pH in batch and fed-batch fermentations. In 48 h batch fermentations with free and constant pH, the optimal pH for cell growth and mannitol production in the first 24 h of incubation was 5.5, whereas that for mannitol production in the second 24 h of incubation was 4.5. To achieve high cell density and mannitol yield simultaneously, a dual-stage pH control strategy was proposed based on the kinetic analysis of mannitol production. The pH value was controlled at 5.5 for the first 12 h of fermentation and subsequently shifted to 4.5 until the fermentation was completed. Under dual-stage pH control fermentation, a 103 g/L yield of mannitol with a volumetric production rate of 3.7 g/L/h was achieved after 28 h. The dual-stage pH control fed-batch fermentation strategy was further developed to improve mannitol yield, wherein the yield increased by 109 % to 215 g/L after 98 h of fermentation. This value is the highest yield of mannitol ever reported using L. brevis.

  8. Effect of the gastrointestinal environment on pH homeostasis of Lactobacillus plantarum and Lactobacillus brevis cells as measured by real-time fluorescence ratio-imaging microscopy.

    PubMed

    Ramos, Cíntia Lacerda; Thorsen, Line; Ryssel, Mia; Nielsen, Dennis S; Siegumfeldt, Henrik; Schwan, Rosane Freitas; Jespersen, Lene

    2014-04-01

    In the present work, an in vitro model of the gastrointestinal tract (GIT) was developed to obtain real-time observations of the pH homeostasis of single cells of probiotic Lactobacillus spp. strains as a measure of their physiological state. Changes in the intracellular pH (pHi) were determined using fluorescence ratio imaging microscopy (FRIM) for potential probiotic strains of Lactobacillus plantarum UFLA CH3 and Lactobacillus brevis UFLA FFC199. Heterogeneous populations were observed, with pHi values ranging from 6.5 to 7.5, 3.5 to 5.6 and 6.5 to 8.0 or higher during passage of saliva (pH 6.4), gastric (pH 3.5) and intestinal juices (pH 6.4), respectively. When nutrients were added to gastric juice, the isolate L. brevis significantly decreased its pH(i) closer to the extracellular pH (pH(ex)) than in gastric juice without nutrients. This was not the case for L. plantarum. This study is the first to produce an in vitro GIT model enabling real-time monitoring of pH homeostasis of single cells in response to the wide range of pH(ex) of the GIT. Furthermore, it was possible to observe the heterogeneous response of single cells. The technique can be used to determine the survival and physiological conditions of potential probiotics and other microorganisms during passage through the GIT.

  9. Inactivation of Escherichia coli, Saccharomyces cerevisiae, and Lactobacillus brevis in Low-fat Milk by Pulsed Electric Field Treatment: A Pilot-scale Study.

    PubMed

    Lee, Gun Joon; Han, Bok Kung; Choi, Hyuk Joon; Kang, Shin Ho; Baick, Seung Chun; Lee, Dong-Un

    2015-01-01

    We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 μs were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The inactivation curves of the test microorganisms were biphasic with an initial lag phase (or shoulder) followed by a phase of rapid inactivation. PEF treatments with a total pulse energy of 200 kJ/L resulted in a 4.5-log reduction in E. coli, a 4.4-log reduction in L. brevis, and a 6.0-log reduction in S. cerevisiae. Total pulse energies of 200 and 250 kJ/L resulted in greater than 5-log reductions in microbial counts in stored PEF-treated milk, and the growth of surviving microorganisms was slow during storage for 15 d at 4℃. PEF treatment did not change milk physical properties such as pH, color, or particle-size distribution (p<0.05). These results indicate that a relatively low electric-field strength of 10 kV/cm can be used to pasteurize low-fat milk.

  10. Hop Resistance in the Beer Spoilage Bacterium Lactobacillus brevis Is Mediated by the ATP-Binding Cassette Multidrug Transporter HorA

    PubMed Central

    Sakamoto, Kanta; Margolles, Abelardo; van Veen, Hendrik W.; Konings, Wil N.

    2001-01-01

    Lactobacillus brevis is a major contaminant of spoiled beer. The organism can grow in beer in spite of the presence of antibacterial hop compounds that give the beer a bitter taste. The hop resistance in L. brevis is, at least in part, dependent on the expression of the horA gene. The deduced amino acid sequence of HorA is 53% identical to that of LmrA, an ATP-binding cassette multidrug transporter in Lactococcus lactis. To study the role of HorA in hop resistance, HorA was functionally expressed in L. lactis as a hexa-histidine-tagged protein using the nisin-controlled gene expression system. HorA expression increased the resistance of L. lactis to hop compounds and cytotoxic drugs. Drug transport studies with L. lactis cells and membrane vesicles and with proteoliposomes containing purified HorA protein identified HorA as a new member of the ABC family of multidrug transporters. PMID:11514522

  11. Inactivation of Escherichia coli, Saccharomyces cerevisiae, and Lactobacillus brevis in Low-fat Milk by Pulsed Electric Field Treatment: A Pilot-scale Study

    PubMed Central

    Han, Bok Kung; Choi, Hyuk Joon; Kang, Shin Ho; Baick, Seung Chun

    2015-01-01

    We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 μs were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The inactivation curves of the test microorganisms were biphasic with an initial lag phase (or shoulder) followed by a phase of rapid inactivation. PEF treatments with a total pulse energy of 200 kJ/L resulted in a 4.5-log reduction in E. coli, a 4.4-log reduction in L. brevis, and a 6.0-log reduction in S. cerevisiae. Total pulse energies of 200 and 250 kJ/L resulted in greater than 5-log reductions in microbial counts in stored PEF-treated milk, and the growth of surviving microorganisms was slow during storage for 15 d at 4℃. PEF treatment did not change milk physical properties such as pH, color, or particle-size distribution (p<0.05). These results indicate that a relatively low electric-field strength of 10 kV/cm can be used to pasteurize low-fat milk. PMID:26877640

  12. Spectrum of Ultrasound Pathologies of Achilles Tendon, Plantar Aponeurosis and Flexor Digiti Brevis Tendon Heel Entheses in Patients with Clinically Suspected Enthesitis

    PubMed Central

    Sudoł-Szopińska, Iwona; Zaniewicz-Kaniewska, Katarzyna; Kwiatkowska, Brygida

    2014-01-01

    Summary Background Enthesitis is considered a characteristic presentation of the second most common group of rheumatoid disorders, i.e. spondyloarthropathies (SpAs), particularly peripheral spondyloarthropathies. At the initial stages, enthesitis may be the only symptom of SpA, particularly in patients lacking the HLA-B27 receptor. Material/Methods In light of diagnostic difficulties with detecting enthesitis in clinical examinations and laboratory investigations, many studies point out the high specificity of imaging studies, and particularly ultrasonography. Results A total of 20% Achilles tendon entheses, 45% plantar aponeurosis entheses and 89.5% of flexor digiti brevis tendon entheses were unremarkable. In the remaining cases, the presentation of pathological lesions was not specific to enthesitis and might more likely correspond to degeneration or microinjuries of the entheses, beside the most obvious cases of achillobursitis or Kager’s fat pad inflammation. Conclusions The studies demonstrated that ultrasound scans rarely confirm the clinical diagnosis of enthesitis. PMID:25674194

  13. Musculoskeletal Management of a Patient With a History of Chronic Ankle Sprains: Identifying Rupture of Peroneal Brevis and Peroneal Longus With Diagnostic Ultrasonography

    PubMed Central

    Bruin, Dick B.; von Piekartz, Harry

    2014-01-01

    Objective The purpose of this case report is to describe the use of mobilization and eccentric exercise training for a patient with ankle pain and a history of chronic ankle sprains and discuss the course of diagnostic decision making when the patient did not respond to care. Clinical Features A 48-year-old police officer who had sustained multiple ankle sprains throughout his life presented with pain and restriction in his ability to walk, run, and work. The Global Rating of Change Scale score was − 6, the Numeric Pain Rating Scale score was 7/10, and the Lower Extremity Functional Scale score was − 33. Palpation of the peroneus longus and brevis muscles and inversion with overpressure reproduced the chief concern (Numeric Pain Rating Scale 7/10). The patient was initially diagnosed with chronic peroneal tendinopathy. Intervention and Outcome Treatment included lateral translation mobilization of the talocrural joint combined with eccentric exercise using an elastic band for the peroneal muscles. The patient reported improvement in pain and function during the course of intervention but not as rapidly as expected. Therefore, follow-up ultrasonographic imaging and radiography were performed. These studies revealed partial rupture of the peroneal brevis muscle and total rupture of the peroneal longus muscle. Conclusion A patient with long-term concerns of the foot complex with a diagnosis of peroneal tendinopathy showed slight improvement with eccentric exercises combined with manual therapy of the talocrural joint. After a course of treatment but minimal response, a diagnosis of tendon rupture was confirmed with diagnostic ultrasonography. Clinicians should be aware that when injuries do not improve with care, tendon rupture should be considered. PMID:25225470

  14. Biosynthesis of 3-hydroxypropionic acid from glycerol in recombinant Escherichia coli expressing Lactobacillus brevis dhaB and dhaR gene clusters and E. coli K-12 aldH.

    PubMed

    Kwak, Suryang; Park, Yong-Cheol; Seo, Jin-Ho

    2013-05-01

    3-Hydroxypropionic acid (3-HP) is a value-added chemical for polymer synthesis. For biosynthesis of 3-HP from glycerol, two dhaB and dhaR clusters encoding glycerol dehydratase and its reactivating factor, respectively, were cloned from Lactobacillus brevis KCTC33069 and expressed in Escherichia coli. Coexpression of dhaB and dhaR allowed the recombinant E. coli to convert glycerol to 3-hydroxypropionaldehyde, an intermediate of 3-HP biosynthesis. To produce 3-HP from glycerol, fed-batch fermentation with a two-step feeding strategy was designed to separate the cell growth from the 3-HP production stages. Finally, E. coli JHS00947 expressing L .brevis dhaB and dhaR, and E. coli aldH produced 14.3g/L 3-HP with 0.26 g/L-h productivity, which were 14.6 and 8.53 times higher than those of the batch culture. In conclusion, overexpression of L. brevis dhaB and dhaR clusters and E. coli aldH, and implementation of the two-step feeding strategy enabled recombinant E. coli to convert glycerol to 3-HP efficiently.

  15. Multi-Sensor Approach for the Monitoring of Halitosis Treatment via Lactobacillus brevis (CD2)—Containing Lozenges—A Randomized, Double-Blind Placebo-Controlled Clinical Trial

    PubMed Central

    Marchetti, Enrico; Tecco, Simona; Santonico, Marco; Vernile, Chiara; Ciciarelli, Daniele; Tarantino, Ester; Marzo, Giuseppe; Pennazza, Giorgio

    2015-01-01

    The aim of this randomized clinical trial was to evaluate whether a recently described multi-sensor approach called BIONOTE® is accurate enough to verify the efficacy of treatment of patients with halitosis. A treatment with Lactobacillus brevis (CD2)–containing lozenges, compared with placebo was tested. The BIONOTE® was compared with traditional techniques used to detect halitosis: OralChroma™ and two calibrated odor judges enrolled for the organoleptic assessments. Twenty patients (10 treated and 10 placebo), suffering from active phase halitosis were included in the study. Treatment consisted of Lactobacillus brevis (CD2)—containing lozenges or placebo, 4 tablets/day for 14 days. t0 was before the beginning of the study; t1 was day 7 and t2 was day 14. The effectiveness of treatment was assessed through: (1) Rosenberg score; (2) Winkel tongue coating index (WTCI) anterior and posterior; (2) OralChroma™; (3) the new developed multi-sensor approach, called BIONOTE® (test technique). Only the WTCI anterior revealed statistically significant changes between t0 and t2 data (p = 0.014) in the treated group. Except for the WTCI anterior, all diagnostic methods revealed the lack of effectiveness for halitosis of a 14-days treatment with Lactobacillus brevis (CD2)–containing lozenges. The BIONOTE® multisensor system seems accurate in addition to OralChroma™ to assess the initial condition of halitosis and its mitigation during treatment. PMID:26266414

  16. Effect of dietary heat-killed Lactobacillus brevis SBC8803 (SBL88™) on sleep: a non-randomised, double blind, placebo-controlled, and crossover pilot study.

    PubMed

    Nakakita, Y; Tsuchimoto, N; Takata, Y; Nakamura, T

    2016-09-01

    We previously reported that dietary heat-killed Lactobacillus brevis SBC8803 affects sleep rhythms in mice. The present study evaluated the effect of consumption of heat-killed SBC8803 on sleep architecture in humans. A non-randomised, placebo-controlled, double blind, and crossover pilot study was conducted using volunteers who scored at a slightly high level (i.e. ≥6) on the Athens Insomnia Scale (AIS). Male subjects (n=17; age 41-69 y) consumed placebo or SBC8803 capsules (25 mg/day of heat-killed SBC8803) for 10 days. Electroencephalograms (EEG) were recorded using a mobile, one-channel system, providing objective data on sleep. Subjects' sleep journals and administration of the AIS provided subjective data on sleep. Three subjects were excluded from the statistical analysis. Analysis of the remaining 14 volunteers revealed no significant differences between placebo and SBC8803 consumption in either the AIS or the sleep EEG. The sleep journals revealed an improvement in 'waking' for the SBC8803 consumption periods (P=0.047), and there was a marginally significant effect on 'drowsiness during the following day' (P=0.067). Effects on the EEG delta power value (μV(2)/min) were revealed by a stratified analysis based on age, AIS, and the Beck Depression Inventory (BDI). Specifically, effects were found among subjects in their 40s who consumed the SBC8803 capsules (P=0.049) and among subjects with a BDI score less than the all-subjects average (13.3) (P=0.045). A marginally significant effect was found among subjects with an AIS score less than the all-subjects average (11.6) (P=0.065). The delta power value of 5 subjects with both BDI and AIS scores less than the average increased significantly (P=0.017). While the number of subjects was limited, a beneficial effect on sleep due to consumption of heat-killed L. brevis SBC8803 was found in subjects with slightly challenged sleep.

  17. Influence of Lactobacillus brevis 15 and Lactobacillus plantarum 13 on blood glucose and body weight in rats after high-fructose diet.

    PubMed

    Yakovlieva, M; Tacheva, T; Mihaylova, S; Tropcheva, R; Trifonova, K; Toleкova, A; Danova, S; Vlaykova, T

    2015-01-01

    In recent years, many authors have investigated the possible antidiabetic effect of lactic acid bacteria. Lactobacillus species constitute a major part of the lactic acid bacteria group and have been found to exhibit beneficial effects on the development of diabetes and its complications. In the current study, we investigated the effects of newly characterised Bulgarian Lactobacillus strains, Lactobacillus brevis 15 and Lactobacillus plantarum 13, on blood glucose levels and body weight of rats fed a fructose-enriched diet. An experiment was conducted over a period of 8 weeks with 24 2-month-old Wistar rats randomly assigned to receive a standard diet (Con, control group), fructose-enriched diet (Fr group), standard diet with probiotics given twice a week (Pro group), and fructose-enriched diet with probiotics given twice a week (Pro+Fr group). At the end of the experimental period, a statistically significant increase in body weight was observed in all experimental groups (P<0.0001). The highest rise was seen in the fructose group (Fr, 169±19 g), followed by the Pro+Fr group (153±15 g), Pro group (149±13 g), and Con group (141±5 g). Moreover, the final blood glucose levels had risen significantly in the groups receiving fructose either without (Fr; P<0.0001) or with lactobacilli (Pro+Fr; P=0.002), while the rise was insignificant in the group of rats given probiotic supplementation only (Pro, P=0.071) and inexistent in the Con group (P=0.999). The highest elevation of blood glucose levels was observed in the Fr group (3.18 mmol/l), followed by the Pro+Fr group (2.00 mmol/l) whereas the Pro group showed the lowest levels (0.60 mmol/l). The results of our study suggest that the newly characterised Bulgarian Lactobacillus strains, L. brevis 15 and L. plantarum 13, could be considered as possible probiotics and might be able to prevent some metabolic disturbances.

  18. Identification by Flagellum Display of an Epithelial Cell- and Fibronectin-Binding Function in the SlpA Surface Protein of Lactobacillus brevis

    PubMed Central

    Hynönen, Ulla; Westerlund-Wikström, Benita; Palva, Airi; Korhonen, Timo K.

    2002-01-01

    Depletion of the SlpA protein from the bacterial surface greatly reduced the adhesion of Lactobacillus brevis ATCC 8287 to the human intestinal cell lines Caco-2 and Intestine 407, the endothelial cell line EA-hy926, and the urinary bladder cell line T24, as well as immobilized fibronectin. For functional analysis of the SlpA surface protein, different regions of the slpA gene were expressed as internal in-frame fusions in the variable region of the fliCH7 gene of Escherichia coli. The resulting chimeric flagella carried inserts up to 275 amino acids long from the mature S-layer protein, which is 435 amino acids in size. The expression of the SlpA fragments on the chimeric flagella was assessed by immunoelectron microscopy and Western blotting using anti-SlpA antibodies, and their binding to human cells was assessed by indirect immunofluorescence. Chimeric flagella harboring inserts that represented the N-terminal part of the S-layer protein bound to the epithelial cell lines, whereas the C-terminal part of the S-layer protein did not confer binding on the flagella. The shortest S-layer peptide capable of detectable binding was 81 amino acid residues in size and represented residues 96 through 176 in the unprocessed S-layer protein. The bacteria and the chimeric flagella did not show detectable binding to erythrocytes, whereas the SlpA-expressing ATCC 8287 cells as well as the chimeric SlpA 96-245/FliC flagella bound to immobilized fibronectin. The N-terminal SlpA peptide 96-176 or 96-200 fused to FliC was not recognized in Western blotting or immunoelectron microscopy by a polyclonal serum raised against the S-layer protein; the antiserum, however, reacted in immunofluorescence with the ATCC 8287 cells. In contrast, an antiserum raised against the His-tagged peptide 96-245 of SlpA bound to the hybrid flagella with the N-terminal SlpA inserts but did not react with ATCC 8287 cells. The results identify the S-layer of L. brevis ATCC 8287 as an adhesin with affinity

  19. Sympathetic and sensory innervations are heterogeneously distributed in relation to the blood vessels at the extensor carpi radialis brevis muscle origin of man.

    PubMed

    Ljung, B O; Forsgren, S; Fridén, J

    1999-01-01

    By using immunohistochemistry and antibodies to a general nerve marker, protein gene product (PGP) 9.5, the overall innervation at the extensor carpi radialis brevis (ECRB) muscle origin was investigated in patients with tennis elbow and in healthy controls. The autonomic innervation was studied by using antibodies to neuropeptide Y (NPY), tyrosine hydroxylase (TH), and vasoactive intestinal peptide (VIP). The sensory innervation was visualized by using antibodies to substance P and calcitonin gene-related peptide. PGP 9.5 immunoreactions were detected in association with small blood vessels and arteries and within nerve bundles. There was, however, heterogeneity in the perivascular nerve fiber distribution since some blood vessels exhibited a high degree of PGP 9.5 innervation and some negligible or no such innervation at all. There was marked TH/NPY innervation in the walls of a subpopulation of the arteries, basically no VIP-containing nerves, and sensory innervation restricted to the small blood vessels. These observations show that the ECRB muscle origin is supplied with heterogeneously distributed sympathetic and sensory innervations and, furthermore, that there appears to be an imbalance between the vasoconstrictor and vasodilator innervations along the vascular tree in this region.

  20. Enhanced survival of shrimp, Penaeus (Marsupenaeus) japonicus from white spot syndrome disease after oral administration of recombinant VP28 expressed in Brevibacillus brevis.

    PubMed

    Caipang, Christopher Marlowe A; Verjan, Noel; Ooi, Ei Lin; Kondo, Hidehiro; Hirono, Ikuo; Aoki, Takashi; Kiyono, Hiroshi; Yuki, Yoshikazu

    2008-09-01

    White spot syndrome virus (WSSV) disease is a major threat to shrimp culture worldwide. Here, we assessed the efficacy of the oral administration of purified recombinant VP28, an envelope protein of WSSV, expressed in a Gram-positive bacterium, Brevibacillus brevis, in providing protection in shrimp, Penaeus japonicus, upon challenge with WSSV. Juvenile shrimp (2-3g in body weight) fed with pellets containing purified recombinant VP28 (50microg/shrimp) for 2 weeks showed significantly higher survival rates than control groups when challenged with the virus at 3 days after the last day of feeding. However, when shrimp were challenged 2 weeks after the last day of feeding, survival rates decreased (33.4% and 24.93%, respectively). Survival rate was dose-dependent, increasing from 60.7 to 80.3% as the dose increased from 1 to 50microg/shrimp. At a dose of 50microg/shrimp, the recombinant protein provided protection as soon as 1 day after feeding (72.5% survival). Similar results were obtained with larger-sized shrimp. These results show that recombinant VP28 expressed in a Gram-positive bacterium is a potential oral vaccine against WSSV.

  1. Amelioration of Citrobacter rodentium proliferation in early stage of infection in mice by pre-treatment with Lactobacillus brevis KB290 and verification using in vivo bioluminescence imaging.

    PubMed

    Waki, Naoko; Kuwabara, Yuki; Yoshikawa, Yuko; Suganuma, Hiroyuki; Koide, Hiroyuki; Oku, Naoto; Ohashi, Norio

    2016-11-10

    Bioluminescent imaging (BLI) has become a useful tool for monitoring bacterial infections in real time. Citrobacter rodentium and its BLI are widely used as a murine model of enteropathogenic and enterohaemorrhagic Escherichia coli infection. In this study, we evaluated the protective effects of the probiotic Lactobacillus brevis KB290 against C. rodentium infection by the BLI approach. First, we examined several solutions for making the suspension of bioluminescent C. rodentium for an oral inoculation to establish a stable intestinal infection. Three percent NaHCO 3 solution was found to be the best. Subsequently, mice were orally administered KB290 once daily for 7 days before inoculation with bioluminescent C. rodentium and for 8 days after infection. The bioluminescence intensity of mice fed with KB290 was significantly lower than that of unfed mice on days 1-3 post-infection . The mRNA levels of tumour necrosis factor-α and interferon-γ in the distal colon from KB290-fed mice were shown to be significantly higher than those from unfed mice on day 3 post-infection. The results suggested that KB290 intake partially inhibited the proliferation of C. rodentium , especially in the early stages of infection, via the moderate enhancement of tumour necrosis factor-α and interferon-γ production in the colon.

  2. Cloning and Characterization of Ginsenoside-Hydrolyzing β-Glucosidase from Lactobacillus brevis That Transforms Ginsenosides Rb1 and F2 into Ginsenoside Rd and Compound K.

    PubMed

    Zhong, Fei-Liang; Ma, Rui; Jiang, Mingliang; Dong, Wei-Wei; Jiang, Jun; Wu, Songquan; Li, Donghao; Quan, Lin-Hu

    2016-10-28

    The ginsenoside-hydrolyzing β-glucosidase gene (bgy2) was cloned from Lactobacillus brevis. We expressed this gene in Escherichia coli BL21(DE3), isolated the resulting protein, and then utilized the enzyme for the biotransformation of ginsenosides. The bgy2 gene contains 2,223 bp, and encodes a protein of 741 amino acids that is a member of glycosyl hydrolase family 3. β-Glucosidase (Bgy2) cleaved the outer glucose moieties of ginsenosides at the C-20 position, and the inner glucose at the C-3 position. Under optimal conditions (pH 7.0, 30°C), we used 0.1 mg/ml Bgy2 in 20 mM sodium phosphate buffer (PBS) for enzymatic studies. In these conditions, 1.0 mg/ml ginsenoside Rb1 and ginsenoside F2 were converted into 0.59 mg/ml ginsenoside Rd and 0.72mg/ml compound K, with molar conversion productivities of 69% and 91%, respectively. In pharmaceutical and commercial industries, this recombinant Bgy2 would be suitable for producting ginsenoside Rd and compound K.

  3. 2-Pyrrolidone synthesis from γ-aminobutyric acid produced by Lactobacillus brevis under solid-state fermentation utilizing toxic deoiled cottonseed cake.

    PubMed

    Grewal, Jasneet; Khare, S K

    2017-01-01

    There is an increasing demand of γ-aminobutyric acid (GABA) as drug and food additive, as well as feedstock to produce 2-pyrrolidone, a precursor for the synthesis of nylon 4. 2-Pyrrolidone is a petrochemical and depleting reserve which raises concern for its bio-based production. The study herein describes bio-based economical GABA production from Lactobacillus brevis by solid-state fermentation (SSF) using toxic deoiled cottonseed cake (CSC) as substrate. In general, the use of cottonseed cake remains restricted due to the presence of toxic gossypols. Thus, simultaneous detoxification observed during fermentation also widens the scope of utilization of this residual seedcake for feed use vis-a-vis production of other value added chemicals. The SSF conditions were optimized for maximum GABA production, viz., 19.7 mg/g, CSC of GABA was obtained at 6th day of fermentation with 70 % degradation of gossypols simultaneously. The potential of this bio-based GABA as a platform chemical is demonstrated in the synthesis of 2-pyrrolidone. Thus, a simple and cost-effective strategy for utilizing toxic biomass has been developed as an alternate to chemical synthetic route.

  4. Partial Purification and Characterization of a Bacteriocin DT24 Produced by Probiotic Vaginal Lactobacillus brevis DT24 and Determination of its Anti-Uropathogenic Escherichia coli Potential.

    PubMed

    Trivedi, Disha; Jena, Prasant Kumar; Patel, Jignesh Kumar; Seshadri, Sriram

    2013-06-01

    The emergence of antibiotic resistance has increased the interest for finding new antimicrobials in the past decade. Probiotic Lactic acid bacteria producing antimicrobial proteins like bacteriocin can be excellent agents for development as novel therapeutic agents and complement to conventional antibiotic therapy. Uropathogenic Escherichia coli, most causative agent of Urinary tract infection, has developed resistance to various antibiotics. In the present investigation, antibacterial substance like bacteriocin (Bacteriocin DT24) produced by probiotic Lactobacillus brevis DT24 from vaginal sample of healthy Indian woman was partially purified and characterized. It was efficiently working against various pathogens, that is, Uropathogenic E. coli, Enterococcus faecium, Enterococcus faecalis and Staphylococcus aureus. The antimicrobial peptide was relatively heat resistant and also active over a broad range of pH 2-10. It has been partially purified by ammonium sulfate precipitation and gel filtration chromatography and checked on reverse-phase high-performance liquid chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of bacteriocin DT24 was approximately 7-kDa protein. The peptide is inactivated by proteolytic enzymes, trypsin and lipase but not when treated with catalase, α-amylase and pepsin. It showed bacteriostatic mode of action against uropathogenic E. coli. Such characteristics indicate that this bacteriocin-producing probiotic may be a potential candidate for alternative agents to control urinary tract infections and other pathogens.

  5. Anti-inflammatory effects of Lactobacillus brevis K65 on RAW 264.7 cells and in mice with dextran sulphate sodium-induced ulcerative colitis.

    PubMed

    Liu, Y-W; Ong, W-K; Su, Y-W; Hsu, C-C; Cheng, T-H; Tsai, Y-C

    2016-06-01

    Lactic acid bacteria (LAB) with anti-inflammatory effects may be beneficial to the prevention or treatment for inflammation-related diseases, such as inflammatory bowel diseases. In an in vitro assay, heat-killed Lactobacillus brevis K65 (K65) reduced lipopolysaccharide-induced production of nitric oxide, tumour necrosis factor (TNF)-α and prostaglandin E2 in RAW 264.7 cells. In RAW 264.7 cells stably expressing an ind=ucible nitric oxide synthase (iNOS) reporter, viable K65 showed greater inhibition of iNOS production than its heat-killed form. In order to further examine the in vivo anti-inflammatory effect of K65, viable K65 was orally administered to BALB/c mice before and during the period of dextran sulphate sodium (DSS)-induced ulcerative colitis (UC). K65 improved UC symptoms, including reduced the levels of the pro-inflammatory cytokines, TNF-α, interleukin (IL)-6 and IL-1β, and lowered the activity of myeloperoxidase. Furthermore, K65 inhibited TNF-α, cyclo-oxygenase 2, forkhead box P3, and Toll-like receptor 4 mRNA expression in the colonic tissue of DSS-induced UC mice. Taken together, K65, a LAB with in vitro anti-inflammatory activity showed preventive effects on mice with DSS-induced UC by lowering the expression of inflammatory molecules.

  6. Characterization and immobilization on nickel-chelated Sepharose of a glutamate decarboxylase A from Lactobacillus brevis BH2 and its application for production of GABA.

    PubMed

    Lee, Ji-Yeon; Jeon, Sung-Jong

    2014-01-01

    A gene encoding glutamate decarboxylase A (GadA) from Lactobacillus brevis BH2 was expressed in a His-tagged form in Escherichia coli cells, and recombinant protein exists as a homodimer consisting of identical subunits of 53 kDa. GadA was absolutely dependent on the ammonium sulfate concentration for catalytic activity and secondary structure formation. GadA was immobilized on the metal affinity resin with an immobilization yield of 95.8%. The pH optima of the immobilized enzyme were identical with those of the free enzyme. However, the optimum temperature for immobilized enzyme was 5 °C higher than that for the free enzyme. The immobilized GadA retained its relative activity of 41% after 30 reuses of reaction within 30 days and exhibited a half-life of 19 cycles within 19 days. A packed-bed bioreactor with immobilized GadA showed a maximum yield of 97.8% GABA from 50 mM l-glutamate in a flow-through system under conditions of pH 4.0 and 55 °C.

  7. Rapid identification of the three major species of dairy obligate heterofermenters Lactobacillus brevis, Lactobacillus fermentum and Lactobacillus parabuchneri by species-specific duplex PCR.

    PubMed

    Coton, Monika; Berthier, Françoise; Coton, Emmanuel

    2008-07-01

    In this study, the biodiversity of 154 strains of lactic acid bacteria, including 112 dairy product isolates presumptively identified as obligately heterofermentative lactobacilli (OHL) by classical microbiological tests, as well as 23 OHL-type strains, was investigated by PCR-based methods and gene sequencing. Using these techniques, 51% of the cheese isolates were actually identified as OHL. The non-OHL isolates were identified to the Leuconostoc, Lactobacillus, Weisella, Pediococcus or Streptococcus genera. Among the OHL cheese isolates, five species were directly identified including three of the most frequently isolated species -Lactobacillus fermentum, Lactobacillus parabuchneri and Lactobacillus brevis- and two rarely isolated species - Lactobacillus diolivorans and Lactobacillus reuteri. A sixth group made up of two dairy isolates was also identified and according to 16S rRNA gene and intergenic spacer region (ISR) sequencing data corresponded to Lactobacillus sp. and may constitute a new species. Species-specific primers were designed for the rapid and reliable detection of the three most frequently isolated species by species-specific duplex PCR.

  8. Highly active β-xylosidases of glycoside hydrolase family 43 operating on natural and artificial substrates.

    PubMed

    Jordan, Douglas B; Wagschal, Kurt; Grigorescu, Arabela A; Braker, Jay D

    2013-05-01

    The hemicellulose xylan constitutes a major portion of plant biomass, a renewable feedstock available for conversion to biofuels and other bioproducts. β-xylosidase operates in the deconstruction of the polysaccharide to fermentable sugars. Glycoside hydrolase family 43 is recognized as a source of highly active β-xylosidases, some of which could have practical applications. The biochemical details of four GH43 β-xylosidases (those from Alkaliphilus metalliredigens QYMF, Bacillus pumilus, Bacillus subtilis subsp. subtilis str. 168, and Lactobacillus brevis ATCC 367) are examined here. Sedimentation equilibrium experiments indicate that the quaternary states of three of the enzymes are mixtures of monomers and homodimers (B. pumilus) or mixtures of homodimers and homotetramers (B. subtilis and L. brevis). k cat and k cat/K m values of the four enzymes are higher for xylobiose than for xylotriose, suggesting that the enzyme active sites comprise two subsites, as has been demonstrated by the X-ray structures of other GH43 β-xylosidases. The K i values for D-glucose (83.3-357 mM) and D-xylose (15.6-70.0 mM) of the four enzymes are moderately high. The four enzymes display good temperature (K t (0.5) ∼ 45 °C) and pH stabilities (>4.6 to <10.3). At pH 6.0 and 25 °C, the enzyme from L. brevis ATCC 367 displays the highest reported k cat and k cat/K m on natural substrates xylobiose (407 s(-1), 138 s(-1) mM(-1)), xylotriose (235 s(-1), 80.8 s(-1) mM(-1)), and xylotetraose (146 s(-1), 32.6 s(-1) mM(-1)).

  9. Hydrodynamics of pulsed jetting in juvenile and adult brief squid Lolliguncula brevis: evidence of multiple jet 'modes' and their implications for propulsive efficiency.

    PubMed

    Bartol, Ian K; Krueger, Paul S; Stewart, William J; Thompson, Joseph T

    2009-06-01

    The dynamics of pulsed jetting in squids throughout ontogeny is not well understood, especially with regard to the development of vortex rings, which are common features of mechanically generated jet pulses (also known as starting jets). Studies of mechanically generated starting jets have revealed a limiting principle for vortex ring formation characterized in terms of a ;formation number' (F), which delineates the transition between the formation of isolated vortex rings and vortex rings that have; pinched off' from the generating jet. Near F, there exists an optimum in pulse-averaged thrust with (potentially) low energetic cost, raising the question: do squids produce vortex rings and if so, do they fall near F, where propulsive benefits presumably occur? To better understand vortex ring dynamics and propulsive jet efficiency throughout ontogeny, brief squid Lolliguncula brevis ranging from 3.3 to 9.1 cm dorsal mantle length (DML) and swimming at speeds of 2.43-22.2 cms(-1) (0.54-3.50 DMLs(-1)) were studied using digital particle image velocimetry (DPIV). A range of jet structures were observed but most structures could be classified as variations of two principal jet modes: (1) jet mode I, where the ejected fluid rolled up into an isolated vortex ring; and (2) jet mode II, where the ejected fluid developed into a leading vortex ring that separated or ;pinched off' from a long trailing jet. The ratio of jet length [based on the vorticity extent (L(omega))] to jet diameter [based on peak vorticity locations (D(omega))] was <3.0 for jet mode I and >3.0 for jet mode II, placing the transition between modes in rough agreement with F determined in mechanical jet studies. Jet mode II produced greater time-averaged thrust and lift forces and was the jet mode most heavily used whereas jet mode I had higher propulsive efficiency, lower slip, shorter jet periods and a higher frequency of fin activity associated with it. No relationship between L(omega)/D(omega) and speed

  10. Biochemical and Molecular Characterization of a Serine Keratinase from Brevibacillus brevis US575 with Promising Keratin-Biodegradation and Hide-Dehairing Activities

    PubMed Central

    Jaouadi, Nadia Zaraî; Rekik, Hatem; Badis, Abdelmalek; Trabelsi, Sahar; Belhoul, Mouna; Yahiaoui, Amina Benkiar; Aicha, Houda Ben; Toumi, Abdessatar; Bejar, Samir; Jaouadi, Bassem

    2013-01-01

    Dehairing is one of the highly polluting operations in the leather industry. The conventional lime-sulfide process used for dehairing produces large amounts of sulfide, which poses serious toxicity and disposal problems. This operation also involves hair destruction, a process that leads to increased chemical oxygen demand (COD), biological oxygen demand (BOD), and total suspended solid (TSS) loads in the effluent. With these concerns in mind, enzyme-assisted dehairing has often been proposed as an alternative method. The main enzyme preparations so far used involved keratinases. The present paper reports on the purification of an extracellular keratinase (KERUS) newly isolated from Brevibacillus brevis strain US575. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis revealed that the purified enzyme was a monomer with a molecular mass of 29121.11 Da. The sequence of the 27 N-terminal residues of KERUS showed high homology with those of Bacillus keratinases. Optimal activity was achieved at pH 8 and 40°C. Its thermoactivity and thermostability were upgraded in the presence of 5 mM Ca2+. The enzyme was completely inhibited by phenylmethanesulfonyl fluoride (PMSF) and diiodopropyl fluorophosphates (DFP), which suggests that it belongs to the serine protease family. KERUS displayed higher levels of hydrolysis, substrate specificity, and catalytic efficiency than NUE 12 MG and KOROPON® MK EG keratinases. The enzyme also exhibited powerful keratinolytic activity that made it able to accomplish the entire feather-biodegradation process on its own. The kerUS gene encoding KERUS was cloned, sequenced, and expressed in Escherichia coli. The biochemical properties of the extracellular purified recombinant enzyme (rKERUS) were similar to those of native KERUS. Overall, the findings provide strong support for the potential candidacy of this enzyme as an effective and eco-friendly alternative to the conventional chemicals used

  11. Enhancement of γ-aminobutyric acid production in recombinant Corynebacterium glutamicum by co-expressing two glutamate decarboxylase genes from Lactobacillus brevis.

    PubMed

    Shi, Feng; Jiang, Junjun; Li, Yongfu; Li, Youxin; Xie, Yilong

    2013-11-01

    γ-Aminobutyric acid (GABA), a non-protein amino acid, is a bioactive component in the food, feed and pharmaceutical fields. To establish an effective single-step production system for GABA, a recombinant Corynebacterium glutamicum strain co-expressing two glutamate decarboxylase (GAD) genes (gadB1 and gadB2) derived from Lactobacillus brevis Lb85 was constructed. Compared with the GABA production of the gadB1 or gadB2 single-expressing strains, GABA production by the gadB1-gadB2 co-expressing strain increased more than twofold. By optimising urea supplementation, the total production of L-glutamate and GABA increased from 22.57 ± 1.24 to 30.18 ± 1.33 g L⁻¹, and GABA production increased from 4.02 ± 0.95 to 18.66 ± 2.11 g L⁻¹ after 84-h cultivation. Under optimal urea supplementation, L-glutamate continued to be consumed, GABA continued to accumulate after 36 h of fermentation, and the pH level fluctuated. GABA production increased to a maximum level of 27.13 ± 0.54 g L⁻¹ after 120-h flask cultivation and 26.32 g L⁻¹ after 60-h fed-batch fermentation. The conversion ratio of L-glutamate to GABA reached 0.60-0.74 mol mol⁻¹. By co-expressing gadB1 and gadB2 and optimising the urea addition method, C. glutamicum was genetically improved for de novo biosynthesis of GABA from its own accumulated L-glutamate.

  12. Long-term effects of oral tea polyphenols and Lactobacillus brevis M8 on biochemical parameters, digestive enzymes, and cytokines expression in broilers.

    PubMed

    Li, Hua-li; Li, Zong-jun; Wei, Zhong-shan; Liu, Ting; Zou, Xiao-zuo; Liao, Yong; Luo, Yu

    2015-12-01

    This study investigates the long-term effects of oral tea polyphenols (TPs) and Lactobacillus brevis M8 (LB) on biochemical parameters, digestive enzymes, and cytokines expression in broilers. In experiment 1, 240 broiler chickens were selected to investigate the effects of 0.06 g/kg body weight (BW) TP and 1.0 ml/kg BW LB on broilers; in experiment 2, 180 broiler chickens were assigned randomly to three groups to investigate the effects of different dosages of TP (0.03, 0.06, and 0.09 g/kg BW) combined with 1.0 ml/kg BW LB on broilers; in experiment 3, 180 broiler chickens were assigned randomly to three groups to investigate the effects of different dosages of LB (0.5, 1.0, and 1.5 ml/kg BW) combined with 0.06 g/kg BW TP on broilers. The results showed that TP and LB affected serum biochemical parameters, and TP reduced serum cholesterol (CHO) and low-density lipoprotein cholesterol (LDL-C) abundances in a dosage-dependent manner (P<0.05) on Day 84. Meanwhile, broilers fed a diet supplemented with TP or LB had a lower intestinal lipase activity on Day 84 compared with the control group (P<0.05). Middle and high dosages of TP increased pancreatic lipase and proventriculus pepsin activities (P<0.05). Also middle and high dosages of LB significantly enhanced pancreatic lipase activity (P<0.05), while high LB supplementation inhibited intestinal trypsase (P<0.05) on Day 84. Furthermore, both TP and LB reduced intestinal cytokine expression and nuclear factor-κ B (NF-κB) mRNA level on Days 56 and 84. In conclusion, long-term treatment of TP and LB improved lipid metabolism and digestive enzymes activities, and affected intestinal inflammatory status, which may be associated with the NF-κB signal.

  13. RT-qPCR analysis of putative beer-spoilage gene expression during growth of Lactobacillus brevis BSO 464 and Pediococcus claussenii ATCC BAA-344(T) in beer.

    PubMed

    Bergsveinson, Jordyn; Pittet, Vanessa; Ziola, Barry

    2012-10-01

    Lactic acid bacteria (LAB) contamination of beer presents a continual economic threat to brewers. Interestingly, only certain isolates of LAB can grow in the hostile beer environment (e.g., as studied here, Lactobacillus brevis BSO 464 (Lb464) and a non-ropy isolate of Pediococcus claussenii ATCC BAA-344(T) (Pc344NR)), indicating that significant genetic specialization is required. The genes hitA, horA, horB, horC, and bsrA, which have been proposed to confer beer-spoiling ability to an organism, are suspected of counteracting the antimicrobial effects of hops. However, these genes are not present in the same combination (if at all) across beer-spoiling organisms. As such, we sought to investigate the extent to which these genes participate during Lb464 and Pc344NR mid-logarithmic growth in beer through reverse transcription quantitative PCR analysis. We first determined the optimal reference gene set needed for data normalization and, for each bacterium, established that two genes were needed for accurate assessment of gene expression. Following this, we found that horA expression was induced for Pc344NR, but not for Lb464, during growth in beer. Instead, horC expression was dramatically increased in Lb464 when growing in beer, whereas no change was detected for the other putative beer-spoilage-related genes. This indicates that HorC may be one of the principle mediators enabling growth of Lb464 in beer, whereas in Pc344NR, this may be attributable to HorA. These findings not only reveal that Lb464 and Pc344NR are unique in their beer-specific genetic expression profile but also indicate that a range of genetic specialization exists among beer-spoilage bacteria.

  14. Surface Display of the Receptor-Binding Region of the Lactobacillus brevis S-Layer Protein in Lactococcus lactis Provides Nonadhesive Lactococci with the Ability To Adhere to Intestinal Epithelial Cells

    PubMed Central

    Åvall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi

    2003-01-01

    Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactococcus lactis NZ9000. Western blot assay of lactococcal cell wall extracts with anti-SlpA antibodies confirmed that the SlpA adhesion domain of the fusion protein was expressed and located within the cell wall layer. Whole-cell enzyme-linked immunosorbent assay and immunofluorescence microscopy verified that the SlpA adhesion-mediating region was accessible on the lactococcal cell surface. In vitro adhesion assays with the human intestinal epithelial cell line Intestine 407 indicated that the recombinant lactococcal cells had gained an ability to adhere to Intestine 407 cells significantly greater than that of wild-type L. lactis NZ9000. Serum inhibition assay further confirmed that adhesion of recombinant lactococci to Intestine 407 cells was indeed mediated by the N terminus-encoding part of the slpA gene. The ability of the receptor-binding region of SlpA to adhere to fibronectin was also confirmed with this lactococcal surface display system. These results show that, with the aid of the receptor-binding region of the L. brevis SlpA protein, the ability to adhere to gut epithelial cells can indeed be transferred to another, nonadhesive, lactic acid bacterium. PMID:12676705

  15. Surface display of the receptor-binding region of the Lactobacillus brevis S-layer protein in Lactococcus lactis provides nonadhesive lactococci with the ability to adhere to intestinal epithelial cells.

    PubMed

    Avall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi

    2003-04-01

    Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactococcus lactis NZ9000. Western blot assay of lactococcal cell wall extracts with anti-SlpA antibodies confirmed that the SlpA adhesion domain of the fusion protein was expressed and located within the cell wall layer. Whole-cell enzyme-linked immunosorbent assay and immunofluorescence microscopy verified that the SlpA adhesion-mediating region was accessible on the lactococcal cell surface. In vitro adhesion assays with the human intestinal epithelial cell line Intestine 407 indicated that the recombinant lactococcal cells had gained an ability to adhere to Intestine 407 cells significantly greater than that of wild-type L. lactis NZ9000. Serum inhibition assay further confirmed that adhesion of recombinant lactococci to Intestine 407 cells was indeed mediated by the N terminus-encoding part of the slpA gene. The ability of the receptor-binding region of SlpA to adhere to fibronectin was also confirmed with this lactococcal surface display system. These results show that, with the aid of the receptor-binding region of the L. brevis SlpA protein, the ability to adhere to gut epithelial cells can indeed be transferred to another, nonadhesive, lactic acid bacterium.

  16. Long-term effects of oral tea polyphenols and Lactobacillus brevis M8 on biochemical parameters, digestive enzymes, and cytokines expression in broilers

    PubMed Central

    Li, Hua-li; Li, Zong-jun; Wei, Zhong-shan; Liu, Ting; Zou, Xiao-zuo; Liao, Yong; Luo, Yu

    2015-01-01

    This study investigates the long-term effects of oral tea polyphenols (TPs) and Lactobacillus brevis M8 (LB) on biochemical parameters, digestive enzymes, and cytokines expression in broilers. In experiment 1, 240 broiler chickens were selected to investigate the effects of 0.06 g/kg body weight (BW) TP and 1.0 ml/kg BW LB on broilers; in experiment 2, 180 broiler chickens were assigned randomly to three groups to investigate the effects of different dosages of TP (0.03, 0.06, and 0.09 g/kg BW) combined with 1.0 ml/kg BW LB on broilers; in experiment 3, 180 broiler chickens were assigned randomly to three groups to investigate the effects of different dosages of LB (0.5, 1.0, and 1.5 ml/kg BW) combined with 0.06 g/kg BW TP on broilers. The results showed that TP and LB affected serum biochemical parameters, and TP reduced serum cholesterol (CHO) and low-density lipoprotein cholesterol (LDL-C) abundances in a dosage-dependent manner (P<0.05) on Day 84. Meanwhile, broilers fed a diet supplemented with TP or LB had a lower intestinal lipase activity on Day 84 compared with the control group (P<0.05). Middle and high dosages of TP increased pancreatic lipase and proventriculus pepsin activities (P<0.05). Also middle and high dosages of LB significantly enhanced pancreatic lipase activity (P<0.05), while high LB supplementation inhibited intestinal trypsase (P<0.05) on Day 84. Furthermore, both TP and LB reduced intestinal cytokine expression and nuclear factor-κ B (NF-κB) mRNA level on Days 56 and 84. In conclusion, long-term treatment of TP and LB improved lipid metabolism and digestive enzymes activities, and affected intestinal inflammatory status, which may be associated with the NF-κB signal. PMID:26642185

  17. Coexpression of Lactobacillus brevis ADH with GDH or G6PDH in Arxula adeninivorans for the synthesis of 1-(R)-phenylethanol.

    PubMed

    Rauter, Marion; Prokoph, Alexandra; Kasprzak, Jakub; Becker, Karin; Baronian, Keith; Bode, Rüdiger; Kunze, Gotthard; Vorbrodt, H- Matthias

    2015-06-01

    The yeast Arxula adeninivorans was used for the overexpression of an ADH gene of Lactobacillus brevis coding for (R)-specific alcohol dehydrogenase (LbADH) to synthesise enantiomerically pure 1-(R)-phenylethanol. Glucose dehydrogenase gene from Bacillus megaterium (BmGDH) or glucose 6-phosphate dehydrogenase of Bacillus pumilus (BpG6PDH) were coexpressed in Arxula to regenerate the cofactor NADPH by oxidising glucose or glucose 6-phosphate. The yeast strain expressing LbADH and BpG6PDH produced 5200 U l(-1) ADH and 370 U l(-1) G6PDH activity, whereas the strain expressing LbADH and BmGDH produced 2700 U l(-1) ADH and 170 U l(-1) GDH activity. However, the crude extract of both strains reduced 40 mM acetophenone to pure 1-(R)-phenylethanol with an enantiomeric excess (ee) of >99 % in 60 min without detectable by-products. An increase in yield was achieved using immobilised crude extracts (IEs), Triton X-100 permeabilised cells (PCs) and permeabilised immobilised cells (PICs) with PICs being most stable with GDH regeneration over 52 cycles. Even though the activity and synthesis rate of 1-(R)-phenylethanol with the BpG6PDH and LbADH coexpressing strain was higher, the BmGDH-LbADH strain was more stable over successive reaction cycles. This, combined with its higher total turnover number (TTN) of 391 mol product per mole NADP(+), makes it the preferred strain for continuous reaction systems. The initial non-optimised semi-continuous reaction produced 9.74 g l(-1) day(-1) or 406 g kg(-1) dry cell weight (dcw) day(-1) isolated 1-(R)-phenylethanol with an ee of 100 % and a TTN of 206 mol product per mole NADP(+). In conclusion, A. adeninivorans is a promising host for LbADH and BpG6PDH or BmGDH production and offers a simple method for the production of enantiomerically pure alcohols.

  18. Directed evolution and mutagenesis of glutamate decarboxylase from Lactobacillus brevis Lb85 to broaden the range of its activity toward a near-neutral pH.

    PubMed

    Shi, Feng; Xie, Yilong; Jiang, Junjun; Wang, Nannan; Li, Yongfu; Wang, Xiaoyuan

    2014-01-01

    Glutamate decarboxylase (GAD) transforms l-glutamate into γ-aminobutyric acid (GABA) with the consumption of a proton. GAD derived from lactic acid bacteria exhibits optimum activity at pH 4.0-5.0 and significantly loses activity at near-neutral pH. To broaden the active range of the GAD GadB1 from Lactobacillus brevis Lb85 toward a near-neutral pH, irrational design using directed evolution and rational design using site-specific mutagenesis were performed. For directed evolution of GadB1, a sensitive high-throughput screening strategy based on a pH indicator was established. One improved mutant, GadB1(T17I/D294G/Q346H), was selected from 800 variants after one round of EP-PCR. It exhibited 3.9- and 25.0-fold increase in activity and catalytic efficiency, respectively at pH 6.0. Through site-specific mutagenesis, several improved mutants were obtained, with GadB1(E312S) being the best one. The combined mutant GadB1(T17I/D294G/E312S/Q346H) showed even higher catalytic efficiency, 13.1- and 43.2-fold that of wild-type GadB1 at pH 4.6 and 6.0, respectively. The amount of GABA produced in gadB1(T17I/D294G/Q346H)-, gadB1(E312S)- and gadB1(T17I/D294G/E312S/Q346H)-expressing Corynebacterium glutamicum ATCC 13032 from endogenous l-glutamate increased by 9.6%, 20.3% and 63.9%, respectively. These results indicate that these mutations have beneficial effects on expanding the active pH range and on GABA biosynthesis, suggesting these GadB1 variants as potent candidates for GABA production.

  19. Atomic resolution structures of R-specific alcohol dehydrogenase from Lactobacillus brevis provide the structural bases of its substrate and cosubstrate specificity.

    PubMed

    Schlieben, Nils Helge; Niefind, Karsten; Müller, Jörg; Riebel, Bettina; Hummel, Werner; Schomburg, Dietmar

    2005-06-17

    The R-specific alcohol dehydrogenase (RADH) from Lactobacillus brevis is an NADP-dependent, homotetrameric member of the extended enzyme family of short-chain dehydrogenases/reductases (SDR) with a high biotechnological application potential. Its preferred in vitro substrates are prochiral ketones like acetophenone with almost invariably a small methyl group as one substituent and a bulky (often aromatic) moiety as the other. On the basis of an atomic-resolution structure of wild-type RADH in complex with NADP and acetophenone, we designed the mutant RADH-G37D, which should possess an improved cosubstrate specificity profile for biotechnological purposes, namely, a preference for NAD rather than NADP. Comparative kinetic measurements with wild-type and mutant RADH showed that this aim was achieved. To characterize the successful mutant structurally, we determined several, partly atomic-resolution, crystal structures of RADH-G37D both as an apo-enzyme and as ternary complex with NAD or NADH and phenylethanol. The increased affinity of RADH-G37D for NAD(H) depends on an interaction between the adenosine ribose moiety of NAD and the inserted aspartate side-chain. A structural comparison between RADH-G37D as apo-enzyme and as a part of a ternary complex revealed significant rearrangements of Ser141, Glu144, Tyr189 and Met205 in the vicinity of the active site. This plasticity contributes to generate a small hydrophobic pocket for the methyl group typical for RADH substrates, and a hydrophobic coat for the second, more variable and often aromatic, substituent. Around Ser141 we even found alternative conformations in the backbone. A structural adaptability in this region, which we describe here for the first time for an SDR enzyme, is probably functionally important, because it concerns Ser142, a member of the highly conserved catalytic tetrad typical for SDR enzymes. Moreover, it affects an extended proton relay system that has been identified recently as a critical

  20. γ-Aminobutyric Acid (GABA) Production and Angiotensin-I Converting Enzyme (ACE) Inhibitory Activity of Fermented Soybean Containing Sea Tangle by the Co-Culture of Lactobacillus brevis with Aspergillus oryzae.

    PubMed

    Jang, Eun Kyeong; Kim, Nam Yeun; Ahn, Hyung Jin; Ji, Geun Eog

    2015-08-01

    To enhance the γ-aminobutyric acid (GABA) content, the optimized fermentation of soybean with added sea tangle extract was evaluated at 30°C and pH 5.0. The medium was first inoculated with Aspergillus oryzae strain FMB S46471 and fermented for 3 days, followed by the subsequent inoculation with Lactobacillus brevis GABA 100. After fermentation for 7 days, the fermented soybean showed approximately 1.9 g/kg GABA and exhibited higher ACE inhibitory activity than the traditional soybean product. Furthermore, several peptides in the fraction containing the highest ACE inhibitory activity were identified. The novel fermented soybean enriched with GABA and ACE inhibitory components has great pharmaceutical and functional food values.

  1. Natural Xanthones

    NASA Astrophysics Data System (ADS)

    Denisova-Dyatlova, O. A.; Glyzin, V. I.

    1982-10-01

    The available information on the abundance of natural xanthones in nature and the methods for the determination of their structure, biogenesis, and pharmacological properties is surveyed and described systematically. The bibliography includes 151 references.

  2. Matematica Natural.

    ERIC Educational Resources Information Center

    Lozano, Patricia; Medearis, Linda

    Matematica Natural (Natural Mathematics) is a mathematics curriculum for young children based on the assumption that they learn mathematics through concrete, real life, relevant experiences and that educational differences rather than cultural differences influence math achievement. The curriculum uses hands-on materials and activities to teach…

  3. Natural Beauty

    ERIC Educational Resources Information Center

    Coy, Mary

    2006-01-01

    In this article, the author describes how her art class students were able to create, in just four class periods, clay relief plaques depicting nature. A lesson on texture speeds up the completion of such a project. Seeing that clay is a natural material with its own unique texture, it seemed fitting that the final product should depict a variety…

  4. Firsthand Nature

    ERIC Educational Resources Information Center

    Gostev, Moses; Weiss, Francesca Michaelides

    2007-01-01

    It's no secret that many school programs don't give children enough opportunity to explore the natural world--i.e., to "mess about" and to have firsthand experience with nature and animals. Not so at the Muscota New School in New York City! This innovative public elementary school actively promotes inquiry-based learning and encourages…

  5. Nature Detectives

    ERIC Educational Resources Information Center

    Harr, Natalie; Lee, Richard E.; Jr.

    2010-01-01

    Richard Louv's "Last Child in the Woods" (2008) added to a growing consensus to get children outside and experiencing nature. Using ideas from place-based education, the authors present a simple year-long project that brings science, nature, and other curriculum standards to life right in your school yard. With a focus on journaling, this project…

  6. The Nature of Natural Languages.

    ERIC Educational Resources Information Center

    Pierce, Joe E.

    A variety of types of evidence are examined to help determine the true nature of "deep structure" and what, if any, implications this has for linguistic theory as well as culture theory generally. The evidence accumulated over the past century on the nature of phonetic and phonemic systems is briefly discussed, and the following areas of…

  7. Natural disasters.

    PubMed

    Cullen, J M

    1980-09-01

    This presentation covers the various types of natural disasters which are faced by investigators throughout the world. Each geophysical substance is discussed, including earth, air and water, and secondary effects including fire. Additionally, four myths associated with disasters are reviewed.

  8. [Natural disasters].

    PubMed

    Smolka, A

    1988-07-01

    The attempt is made to illustrate the role played by natural disasters in the history of the earth and mankind by examples of past catastrophes. Subsequently, the earthquake of Tangshan/China in 1976 and the hypothetical scenario of a repeat of the 1906 San Francisco earthquake in a modern setting serve as a basis for discussion of the significance of natural disasters in modern times.

  9. Initial Evaluation of the Effects of Aerosolized Florida Red Tide Toxins (Brevetoxins) in Persons with Asthma

    PubMed Central

    Fleming, Lora E.; Kirkpatrick, Barbara; Backer, Lorraine C.; Bean, Judy A.; Wanner, Adam; Dalpra, Dana; Tamer, Robert; Zaias, Julia; Cheng, Yung Sung; Pierce, Richard; Naar, Jerome; Abraham, William; Clark, Richard; Zhou, Yue; Henry, Michael S.; Johnson, David; Van De Bogart, Gayl; Bossart, Gregory D.; Harrington, Mark; Baden, Daniel G.

    2005-01-01

    Florida red tides annually occur in the Gulf of Mexico, resulting from blooms of the marine dinoflagellate Karenia brevis. K. brevis produces highly potent natural polyether toxins, known as brevetoxins, that activate voltage-sensitive sodium channels. In experimental animals, brevetoxins cause significant bronchoconstriction. A study of persons who visited the beach recreationally found a significant increase in self-reported respiratory symptoms after exposure to aerosolized Florida red tides. Anecdotal reports indicate that persons with underlying respiratory diseases may be particularly susceptible to adverse health effects from these aerosolized toxins. Fifty-nine persons with physician-diagnosed asthma were evaluated for 1 hr before and after going to the beach on days with and without Florida red tide. Study participants were evaluated with a brief symptom questionnaire, nose and throat swabs, and spirometry approved by the National Institute for Occupational Safety and Health. Environmental monitoring, water and air sampling (i.e., K. brevis, brevetoxins, and particulate size distribution), and personal monitoring (for toxins) were performed. Brevetoxin concentrations were measured by liquid chromatography mass spectrometry, high-performance liquid chromatography, and a newly developed brevetoxin enzyme-linked immunosorbent assay. Participants were significantly more likely to report respiratory symptoms after Florida red tide exposure. Participants demonstrated small but statistically significant decreases in forced expiratory volume in 1 sec, forced expiratory flow between 25 and 75%, and peak expiratory flow after exposure, particularly those regularly using asthma medications. Similar evaluation during nonexposure periods did not significantly differ. This is the first study to show objectively measurable adverse health effects from exposure to aerosolized Florida red tide toxins in persons with asthma. Future studies will examine the possible chronic

  10. Effects of Enteric-coated Lactoferrin Tablets Containing Lactobacillus brevis subsp. coagulans on Fecal Properties, Defecation Frequency and Intestinal Microbiota of Japanese Women with a Tendency for Constipation: a Randomized Placebo-controlled Crossover Study

    PubMed Central

    SUZUKI, Noriyuki; MURAKOSHI, Michiaki; ONO, Tomoji; MORISHITA, Satoru; KOIDE, Misao; BAE, Min Jung; TOTSUKA, Mamoru; SHIMIZU, Makoto; SUGIYAMA, Keikichi; NISHINO, Hoyoku; IIDA, Norio

    2013-01-01

    The effects of oral administration of enteric-coated tablets containing lactoferrin (LF; 100 mg/tablet) and heat-killed Lactobacillus brevis subsp. coagulans FREM BP-4693 (LB; 6×109 bacteria/tablet) on fecal properties were examined in 32 Japanese women (20–60 years of age) with a tendency for constipation (defecation frequency at equal to or less than 10 times/2 weeks) by a double-blind placebo-controlled crossover design. A significant increase in defecation days per week was obserbed in the subjects who ingested the tablets containing LF and LB compared with the placebo group. The number of bifidobacteria in feces also significantly increased compared with the placebo group. In an in vitro study, LF and tryptic hydrolysate of LF, but not peptic hydrolysate of LF, upregulated the growth of Bifidobacterium longum ATCC15707 when added to the culture. These results demonstrate the capability of the enteric-coated tablets containing LF and LB in improving intestinal function and suggest that they have a growth promoting function for bifidobacteria. PMID:24936358

  11. Nature's Palette

    ERIC Educational Resources Information Center

    McBride, Brooke B.; Brewer, Carol A.

    2010-01-01

    Flower petals, acorn hats, exoskeletons of beetles, and lichens are just a few of the objects students may find in a surprising array of vivid colors. These tiny examples from nature's palette can be discovered in a school yard, a park, or even along the edges of a paved sidewalk...it simply takes careful observation! This article describes a…

  12. Natural restoration

    SciTech Connect

    Kamlet, K.S.

    1993-02-01

    After a company pays millions of dollars to clean up contaminated site, its liability may not be over. It may have to spend tens of millions more to restore damaged natural resources under an oft-overlooked Superfund program. Examples of liability are cited in this report from the Exxon Valdez oil spill and a pcb leak which contaminated a harbor.

  13. Uranium, natural

    Integrated Risk Information System (IRIS)

    Uranium , natural ; CASRN 7440 - 61 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  14. Natural ecosystems

    USGS Publications Warehouse

    Fleishman, Erica; Belnap, Jayne; Cobb, Neil; Enquist, Carolyn A.F.; Ford, Karl; MacDonald, Glen; Pellant, Mike; Schoennagel, Tania; Schmit, Lara M.; Schwartz, Mark; van Drunick, Suzanne; Westerling, Anthony LeRoy; Keyser, Alisa; Lucas, Ryan

    2013-01-01

    Natural Ecosystems analyzes the association of observed changes in climate with changes in the geographic distributions and phenology (the timing of blossoms or migrations of birds) for Southwestern ecosystems and their species, portraying ecosystem disturbances—such as wildfires and outbreaks of forest pathogens—and carbon storage and release, in relation to climate change.

  15. Nature Watch

    ERIC Educational Resources Information Center

    Sterling, Donna R.

    2010-01-01

    Children are naturally curious about the world in which they live. To focus this sense of wonder, have your students investigate their local habitat as it changes over the year. This multiseason study will build connections and add relevance to the habitats that children learn about. This series of activities for grades 4-6 explores the changing…

  16. Harmful Algal Blooms of the West Florida Shelf and Campeche Bank: Visualization and Quantification using Remote Sensing Methods

    NASA Astrophysics Data System (ADS)

    Soto Ramos, Inia Mariel

    Harmful Algal Blooms (HABs) in the Gulf of Mexico (GOM) are natural phenomena that can have negative impacts on marine ecosystems on which human health and the economy of some Gulf States depends. Many of the HABs in the GOM are dominated by the toxic dinoflagellate Karenia brevis. Non-toxic phytoplankton taxa such as Scrippsiella sp. also form intense blooms off the Mexican coast that result in massive fish mortality and economic losses, particularly as they may lead to anoxia. The main objectives of this dissertation were to (1) evaluate and improve the techniques developed for detection of Karenia spp. blooms on the West Florida Shelf (WFS) using satellite remote sensing methods, (2) test the use of these methods for waters in the GOM, and (3) use the output of these techniques to better understand the dynamics and evolution of Karenia spp. blooms in the WFS and off Mexico. The first chapter of this dissertation examines the performance of several Karenia HABs detection techniques using Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images and historical ground truth observations collected on the WFS from August 2002 to December 2011. A total of 2323 in situ samples collected by the Florida Fish and Wildlife Research Institute to test for Karenia spp. matched pixels with valid ocean color satellite observations over this period. This dataset was used to systematically optimize variables and coefficients used in five published HAB detection methods. Each technique was tested using a set of metrics that included the F-Measure (FM). Before optimization, the average FM for all techniques was 0.47. After optimization, the average FM increased to 0.59, and false positives decreased ~50%. The addition of a Fluorescence Line Height (FLH) criterion improved the performance of every method. A new practical method was developed using a combination of FLH and Remote Sensing Reflectance at 555 nm (Rrs555-FLH). The new method resulted in an FM of 0.62 and 3

  17. Brevetoxin, the Dinoflagellate Neurotoxin, Localizes to Thylakoid Membranes and Interacts with the Light-Harvesting Complex II (LHCII) of Photosystem II.

    PubMed

    Cassell, Ryan T; Chen, Wei; Thomas, Serge; Liu, Li; Rein, Kathleen S

    2015-05-04

    The brevetoxins are neurotoxins that are produced by the "Florida red tide" dinoflagellate Karenia brevis. They bind to and activate the voltage-gated sodium channels in higher organisms, specifically the Nav 1.4 and Nav 1.5 channel subtypes. However, the native physiological function that the brevetoxins perform for K. brevis is unknown. By using fluorescent and photoactivatable derivatives, brevetoxin was shown to localize to the chloroplast of K. brevis where it binds to the light-harvesting complex II (LHCII) and thioredoxin. The LHCII is essential to non-photochemical quenching (NPQ), whereas thioredoxins are critical to the maintenance of redox homeostasis within the chloroplast and contribute to the scavenging of reactive oxygen. A culture of K. brevis producing low levels of toxin was shown to be deficient in NPQ and produced reactive oxygen species at twice the rate of the toxic culture, implicating a role in NPQ for the brevetoxins.

  18. Metabolomics and proteomics reveal impacts of chemically mediated competition on marine plankton

    PubMed Central

    Poulson-Ellestad, Kelsey L.; Jones, Christina M.; Roy, Jessie; Viant, Mark R.; Fernández, Facundo M.; Kubanek, Julia; Nunn, Brook L.

    2014-01-01

    Competition is a major force structuring marine planktonic communities. The release of compounds that inhibit competitors, a process known as allelopathy, may play a role in the maintenance of large blooms of the red-tide dinoflagellate Karenia brevis, which produces potent neurotoxins that negatively impact coastal marine ecosystems. K. brevis is variably allelopathic to multiple competitors, typically causing sublethal suppression of growth. We used metabolomic and proteomic analyses to investigate the role of chemically mediated ecological interactions between K. brevis and two diatom competitors, Asterionellopsis glacialis and Thalassiosira pseudonana. The impact of K. brevis allelopathy on competitor physiology was reflected in the metabolomes and expressed proteomes of both diatoms, although the diatom that co-occurs with K. brevis blooms (A. glacialis) exhibited more robust metabolism in response to K. brevis. The observed partial resistance of A. glacialis to allelopathy may be a result of its frequent exposure to K. brevis blooms in the Gulf of Mexico. For the more sensitive diatom, T. pseudonana, which may not have had opportunity to evolve resistance to K. brevis, allelopathy disrupted energy metabolism and impeded cellular protection mechanisms including altered cell membrane components, inhibited osmoregulation, and increased oxidative stress. Allelopathic compounds appear to target multiple physiological pathways in sensitive competitors, demonstrating that chemical cues in the plankton have the potential to alter large-scale ecosystem processes including primary production and nutrient cycling. PMID:24889616

  19. Metabolomics and proteomics reveal impacts of chemically mediated competition on marine plankton.

    PubMed

    Poulson-Ellestad, Kelsey L; Jones, Christina M; Roy, Jessie; Viant, Mark R; Fernández, Facundo M; Kubanek, Julia; Nunn, Brook L

    2014-06-17

    Competition is a major force structuring marine planktonic communities. The release of compounds that inhibit competitors, a process known as allelopathy, may play a role in the maintenance of large blooms of the red-tide dinoflagellate Karenia brevis, which produces potent neurotoxins that negatively impact coastal marine ecosystems. K. brevis is variably allelopathic to multiple competitors, typically causing sublethal suppression of growth. We used metabolomic and proteomic analyses to investigate the role of chemically mediated ecological interactions between K. brevis and two diatom competitors, Asterionellopsis glacialis and Thalassiosira pseudonana. The impact of K. brevis allelopathy on competitor physiology was reflected in the metabolomes and expressed proteomes of both diatoms, although the diatom that co-occurs with K. brevis blooms (A. glacialis) exhibited more robust metabolism in response to K. brevis. The observed partial resistance of A. glacialis to allelopathy may be a result of its frequent exposure to K. brevis blooms in the Gulf of Mexico. For the more sensitive diatom, T. pseudonana, which may not have had opportunity to evolve resistance to K. brevis, allelopathy disrupted energy metabolism and impeded cellular protection mechanisms including altered cell membrane components, inhibited osmoregulation, and increased oxidative stress. Allelopathic compounds appear to target multiple physiological pathways in sensitive competitors, demonstrating that chemical cues in the plankton have the potential to alter large-scale ecosystem processes including primary production and nutrient cycling.

  20. Nature's pumps

    NASA Astrophysics Data System (ADS)

    Vogel, Steven

    1994-10-01

    Although diverse in both form and function, the fluid-forcing devices in organisms have many of the capabilities and limitations of pumps of human design. Nature's pumps certainly look quite different from those of our technology, but all of them perform the same task. The author examines a few of these with an eye toward technological parallels and the two functional classes -- positive-displacement pumps and fluid-dynamic pumps.

  1. Satellite (Natural)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    In its most general sense, any celestial object in orbit around a similar larger object. Thus, for example, the Magellanic Clouds are satellite galaxies of our own Milky Way galaxy. Without qualification, the term is used to mean a body in orbit around a planet; an alternative term is moon. The term natural satellite distinguishes these bodies from artificial satellites—spacecraft placed in orbi...

  2. Natural inflation

    SciTech Connect

    Frieman, J.A.

    1991-02-01

    A pseduo-Nambu-Goldstone boson, with a potential of the form V({phi}) = {Lambda}{sup 4}(1 {plus minus} cos({phi}/f)), can naturally give rise to an epoch of inflation in the early universe. Successful inflation can be achieved if f {approximately} m{sub pl} and {Lambda} {approximately} m{sub GUT}. Such mass scales arise in particle physics models with a gauge group that becomes strongly interacting a the GUT scale, e.g., as is expected to happen in the hidden sector of superstring theories. The density fluctuation spectrum is a non-scale-invariant power law, with extra power on large scales. 12 refs., 3 figs.

  3. Natural Strain

    NASA Technical Reports Server (NTRS)

    Freed, Alan D.

    1995-01-01

    The purpose of this paper is to present a consistent and thorough development of the strain and strain-rate measures affiliated with Hencky. Natural measures for strain and strain-rate, as I refer to them, are first expressed in terms of of the fundamental body-metric tensors of Lodge. These strain and strain-rate measures are mixed tensor fields. They are mapped from the body to space in both the Eulerian and Lagrangian configurations, and then transformed from general to Cartesian fields. There they are compared with the various strain and strain-rate measures found in the literature. A simple Cartesian description for Hencky strain-rate in the Lagrangian state is obtained.

  4. Natural relaxation

    NASA Astrophysics Data System (ADS)

    Marzola, Luca; Raidal, Martti

    2016-11-01

    Motivated by natural inflation, we propose a relaxation mechanism consistent with inflationary cosmology that explains the hierarchy between the electroweak scale and Planck scale. This scenario is based on a selection mechanism that identifies the low-scale dynamics as the one that is screened from UV physics. The scenario also predicts the near-criticality and metastability of the Standard Model (SM) vacuum state, explaining the Higgs boson mass observed at the Large Hadron Collider (LHC). Once Majorana right-handed neutrinos are introduced to provide a viable reheating channel, our framework yields a corresponding mass scale that allows for the seesaw mechanism as well as for standard thermal leptogenesis. We argue that considering singlet scalar dark matter extensions of the proposed scenario could solve the vacuum stability problem and discuss how the cosmological constant problem is possibly addressed.

  5. The social nature of natural childbirth.

    PubMed

    Mansfield, Becky

    2008-03-01

    This paper aims to develop a better understanding of what proponents of natural childbirth mean by "natural." Using a biosocial approach to birth that posits that all birth is both social and natural, the paper investigates how proponents represent the relationship between nature and society. The study asks about what kinds of nature-society relationships are expressed in proponents' representations of natural childbirth. The study examines how natural childbirth is represented by proponents in popular non-fictional English language books written for pregnant women. Claims in these books are not taken as reality, but are analyzed as ideas about nature-society relations. The central finding is that these authors simultaneously emphasize the naturalness of birth and showcase three types of social practices that they describe as being integral to natural childbirth: (1) activity during birth, (2) preparation before birth, and (3) social support, both in an individual and in a broader socio-cultural sense. At least for these authors, it is these social practices that allow natural childbirth to be natural. These findings on the social nature of natural childbirth challenge current social science scholarship, in which natural childbirth is characterized as an essentializing and nostalgic attempt to return to nature.

  6. Review of Florida Red Tide and Human Health Effects.

    PubMed

    Fleming, Lora E; Kirkpatrick, Barbara; Backer, Lorraine C; Walsh, Cathy J; Nierenberg, Kate; Clark, John; Reich, Andrew; Hollenbeck, Julie; Benson, Janet; Cheng, Yung Sung; Naar, Jerome; Pierce, Richard; Bourdelais, Andrea J; Abraham, William M; Kirkpatrick, Gary; Zaias, Julia; Wanner, Adam; Mendes, Eliana; Shalat, Stuart; Hoagland, Porter; Stephan, Wendy; Bean, Judy; Watkins, Sharon; Clarke, Tainya; Byrne, Margaret; Baden, Daniel G

    2011-01-01

    This paper reviews the literature describing research performed over the past decade on the known and possible exposures and human health effects associated with Florida red tides. These harmful algal blooms are caused by the dinoflagellate, Karenia brevis, and similar organisms, all of which produce a suite of natural toxins known as brevetoxins. Florida red tide research has benefited from a consistently funded, long term research program, that has allowed an interdisciplinary team of researchers to focus their attention on this specific environmental issue-one that is critically important to Gulf of Mexico and other coastal communities. This long-term interdisciplinary approach has allowed the team to engage the local community, identify measures to protect public health, take emerging technologies into the field, forge advances in natural products chemistry, and develop a valuable pharmaceutical product. The Review includes a brief discussion of the Florida red tide organisms and their toxins, and then focuses on the effects of these toxins on animals and humans, including how these effects predict what we might expect to see in exposed people.

  7. Applications of satellite ocean color sensors for monitoring and predicting harmful algal blooms

    USGS Publications Warehouse

    Stumpf, Richard P.

    2001-01-01

    The new satellite ocean color sensors offer a means of detecting and monitoring algal blooms in the ocean and coastal zone. Beginning with SeaWiFS (Sea Wide Field-of-view Sensor) in September 1997, these sensors provide coverage every 1 to 2 days with 1-km pixel view at nadir. Atmospheric correction algorithms designed for the coastal zone combined with regional chlorophyll algorithms can provide good and reproducible estimates of chlorophyll, providing the means of monitoring various algal blooms. Harmful algal blooms (HABs) caused by Karenia brevis in the Gulf of Mexico are particularly amenable to remote observation. The Gulf of Mexico has relatively clear water and K. brevis, in bloom conditions, tends to produce a major portion of the phytoplankton biomass. A monitoring program has begun in the Gulf of Mexico that integrates field data from state monitoring programs with satellite imagery, providing an improved capability for the monitoring of K. brevis blooms.

  8. Further insights into brevetoxin metabolism by de novo radiolabeling.

    PubMed

    Calabro, Kevin; Guigonis, Jean-Marie; Teyssié, Jean-Louis; Oberhänsli, François; Goudour, Jean-Pierre; Warnau, Michel; Bottein, Marie-Yasmine Dechraoui; Thomas, Olivier P

    2014-06-10

    The toxic dinoflagellate Karenia brevis, responsible for early harmful algal blooms in the Gulf of Mexico, produces many secondary metabolites, including potent neurotoxins called brevetoxins (PbTx). These compounds have been identified as toxic agents for humans, and they are also responsible for the deaths of several marine organisms. The overall biosynthesis of these highly complex metabolites has not been fully ascertained, even if there is little doubt on a polyketide origin. In addition to gaining some insights into the metabolic events involved in the biosynthesis of these compounds, feeding studies with labeled precursors helps to discriminate between the de novo biosynthesis of toxins and conversion of stored intermediates into final toxic products in the response to environmental stresses. In this context, the use of radiolabeled precursors is well suited as it allows working with the highest sensitive techniques and consequently with a minor amount of cultured dinoflagellates. We were then able to incorporate [U-¹⁴C]-acetate, the renowned precursor of the polyketide pathway, in several PbTx produced by K. brevis. The specific activities of PbTx-1, -2, -3, and -7, identified by High-Resolution Electrospray Ionization Mass Spectrometer (HRESIMS), were assessed by HPLC-UV and highly sensitive Radio-TLC counting. We demonstrated that working at close to natural concentrations of acetate is a requirement for biosynthetic studies, highlighting the importance of highly sensitive radiolabeling feeding experiments. Quantification of the specific activity of the four, targeted toxins led us to propose that PbTx-1 and PbTx-2 aldehydes originate from oxidation of the primary alcohols of PbTx-7 and PbTx-3, respectively. This approach will open the way for a better comprehension of the metabolic pathways leading to PbTx but also to a better understanding of their regulation by environmental factors.

  9. The human health effects of Florida red tide (FRT) blooms: an expanded analysis.

    PubMed

    Hoagland, Porter; Jin, Di; Beet, Andrew; Kirkpatrick, Barbara; Reich, Andrew; Ullmann, Steve; Fleming, Lora E; Kirkpatrick, Gary

    2014-07-01

    Human respiratory and digestive illnesses can be caused by exposures to brevetoxins from blooms of the marine alga Karenia brevis, also known as Florida red tide (FRT). K. brevis requires macro-nutrients to grow; although the sources of these nutrients have not been resolved completely, they are thought to originate both naturally and anthropogenically. The latter sources comprise atmospheric depositions, industrial effluents, land runoffs, or submerged groundwater discharges. To date, there has been only limited research on the extent of human health risks and economic impacts due to FRT. We hypothesized that FRT blooms were associated with increases in the numbers of emergency room visits and hospital inpatient admissions for both respiratory and digestive illnesses. We sought to estimate these relationships and to calculate the costs of associated adverse health impacts. We developed environmental exposure-response models to test the effects of FRT blooms on human health, using data from diverse sources. We estimated the FRT bloom-associated illness costs, using extant data and parameters from the literature. When controlling for resident population, a proxy for tourism, and seasonal and annual effects, we found that increases in respiratory and digestive illnesses can be explained by FRT blooms. Specifically, FRT blooms were associated with human health and economic effects in older cohorts (≥55 years of age) in six southwest Florida counties. Annual costs of illness ranged from $60,000 to $700,000 annually, but these costs could exceed $1.0 million per year for severe, long-lasting FRT blooms, such as the one that occurred during 2005. Assuming that the average annual illness costs of FRT blooms persist into the future, using a discount rate of 3%, the capitalized costs of future illnesses would range between $2 and 24 million.

  10. Sublethal red tide toxin exposure in free-ranging manatees (Trichechus manatus) affects the immune system through reduced lymphocyte proliferation responses, inflammation, and oxidative stress.

    PubMed

    Walsh, Catherine J; Butawan, Matthew; Yordy, Jennifer; Ball, Ray; Flewelling, Leanne; de Wit, Martine; Bonde, Robert K

    2015-04-01

    The health of many Florida manatees (Trichechus manatus latirostris) is adversely affected by exposure to blooms of the toxic dinoflagellate, Karenia brevis. K. brevis blooms are common in manatee habitats of Florida's southwestern coast and produce a group of cyclic polyether toxins collectively referred to as red tide toxins, or brevetoxins. Although a large number of manatees exposed to significant levels of red tide toxins die, several manatees are rescued from sublethal exposure and are successfully treated and returned to the wild. Sublethal brevetoxin exposure may potentially impact the manatee immune system. Lymphocyte proliferative responses and a suite of immune function parameters in the plasma were used to evaluate effects of brevetoxin exposure on health of manatees rescued from natural exposure to red tide toxins in their habitat. Blood samples were collected from rescued manatees at Lowry Park Zoo in Tampa, FL and from healthy, unexposed manatees in Crystal River, FL. Peripheral blood leukocytes (PBL) isolated from whole blood were stimulated with T-cell mitogens, ConA and PHA. A suite of plasma parameters, including plasma protein electrophoresis profiles, lysozyme activity, superoxide dismutase (SOD) activity, and reactive oxygen/nitrogen (ROS/RNS) species, was also used to assess manatee health. Significant decreases (p<0.05) in lymphocyte proliferation were observed in ConA and PHA stimulated lymphocytes from rescued animals compared to non-exposed animals. Significant correlations were observed between oxidative stress markers (SOD, ROS/RNS) and plasma brevetoxin concentrations. Sublethal exposure to brevetoxins in the wild impacts some immune function components, and thus, overall health, in the Florida manatee.

  11. Bacillus species isolated from tungrymbai and bekang, naturally fermented soybean foods of India.

    PubMed

    Chettri, Rajen; Tamang, Jyoti Prakash

    2015-03-16

    Tungrymbai and bekang are naturally fermented soybean foods commonly consumed in Meghalaya and Mizoram states of India. A total of 39 samples of tungrymbai and 43 samples of bekang were collected from different villages and markets of Meghalaya and Mizoram, respectively and were analysed for microbial load. In both tungrymbai and bekang, the average population of Bacillus spp. was 8.2±0.1 log cfu/g. A total of 428 isolates of Bacillus were isolated from tungrymbai (211) and bekang (217) for detailed identification. On the basis of a combination of phenotypic and molecular characterisation using ARDRA, ITS-PCR and RAPD-PCR techniques, species of Bacillus isolated from tungrymbai were identified as Bacillus licheniformis (25.5%), Bacillus pumilus (19.5%) and Bacillus subtilis (55%), and species of Bacillus from bekang were Bacillus brevis (2%), Bacillus circulans (7.5%), Bacillus coagulans (6.5%), B. licheniformis (16.5%), B. pumilus (9.1%), Bacillus sphaericus (4.6%), B. subtilis (51.8%), and Lysinibacillus fusiformis (2%). The most dominant bacterium in both products was B. subtilis.

  12. Toxic and harmful marine phytoplankton and microalgae (HABs) in Mexican Coasts.

    PubMed

    Hernández-Becerril, David U; Alonso-Rodríguez, Rosalba; Alvarez-Góngora, Cynthia; Barón-Campis, Sofia A; Ceballos-Corona, Gerardo; Herrera-Silveira, Jorge; Meave Del Castillo, María E; Juárez-Ruíz, Norma; Merino-Virgilio, Fanny; Morales-Blake, Alejandro; Ochoa, José L; Orellana-Cepeda, Elizabeth; Ramírez-Camarena, Casimiro; Rodríguez-Salvador, Raciel

    2007-08-01

    Harmful Algal Blooms (HABs) are becoming an increasing problem to human health and environment (including effects on natural and cultured resources, tourism and ecosystems) all over the world. In Mexico a number of human fatalities and important economic losses have occurred in the last 30 years because of these events. There are about 70 species of planktonic and non-planktonic microalgae considered harmful in Mexican coasts. The most important toxin-producing species are the dinoflagellates Gymnodinium catenatum and Pyrodinium bahamense var. compressum, in the Mexican Pacific, and Karenia brevis in the Gulf of Mexico, and consequently the poisonings documented in Mexico are Paralytic Shellfish Poisoning (PSP) and Neurotoxic Shellfish Poisoning (NSP). Although there is evidence that Amnesic Shellfish Poisoning (ASP), Diarrhetic Shellfish Poisoning (DSP) and Ciguatera Fish Poisoning (CFP) also occur in Mexico, these problems are reported less frequently. The type of phytoplankton and epiphytic microalgae, their toxins and harmful effects as well as current methodology used to study these phenomena are presented in this paper. As an experienced group of workers, we include descriptions of monitoring and mitigation programs, our proposals for collaborative projects and perspectives on future research.

  13. Natural Language Processing.

    ERIC Educational Resources Information Center

    Chowdhury, Gobinda G.

    2003-01-01

    Discusses issues related to natural language processing, including theoretical developments; natural language understanding; tools and techniques; natural language text processing systems; abstracting; information extraction; information retrieval; interfaces; software; Internet, Web, and digital library applications; machine translation for…

  14. Determination of brevetoxin in recent marine sediments.

    PubMed

    Mendoza, Wilson G; Mead, Ralph N; Brand, Larry E; Shea, Damian

    2008-11-01

    Harmful algal blooms (HAB) of Karenia brevis (K. brevis) produce a suite of lipid soluble polyether brevetoxins, known to cause environmental, health and economic ill effects. There is evidence that K. brevis has increased in abundance over the past 50 years, but the dataset is incomplete. The objective of this paper was to analyze sediment from an area where K. brevis blooms have occurred and investigate if these compounds are incorporated into the underlying sediment, thus potentially allowing the use of brevetoxins as an indicator of past K. Brevis blooms. The results from LC-ESI-MS-MS analyses of brevetoxin analogs detected in surficial sediments from three sites (Fort Meyers Beach [FMB], Big Hickory Pass [BHP] and Big Carlos Pass [BCP]) along the Southwest Florida coastline with prior HAB history are promising. The analogs detected from BHP sediments were PbTx-2 and PbTx-3 with values of 0.81 and 3.1 ng g(-1) dry sediment, respectively. The detected PbTx-2 from BCP was 3.6 ng g(-1) dry sediment, while the detected PbTx-3 from BCP was 9.7 ng g(-1) dry sediment. PbTx-3 was only detected at the FMB site (2.7 ng g(-1) dry sediment). The detection of brevetoxins in recent sediments where K. brevis have occurred indicates brevetoxin incorporation into marine sediments.

  15. The nature and ethics of natural experiments.

    PubMed

    Dawson, Angus; Sim, Julius

    2015-10-01

    Natural experiments are an important methodology often used to answer research questions that would, otherwise, be impossible to address, or employed because of ethical concerns about the use of randomisation to interventions that carry known risks. The UK Medical Research Council (MRC) recently produced an extremely useful document discussing the nature and significance of natural experiments within medical and public health research. In this paper, however, we suggest that the MRC document's definition of the term 'natural experiment' is insufficiently precise. In response, we offer a taxonomy of different types of natural experiments and related methods, and explore the ethical implications of these different types. We argue that while the ethical issues that may arise within natural experiments in relation to risks of harm or informed consent may differ from those within the randomised controlled trial, they are not thereby less pressing. The implications of the argument are explored and recommendations made for those involved in research governance.

  16. Naturally occurring chemical carcinogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural products are chemicals found in nature which have unique pharmacological effects. Humans are exposed to many of these bioactive naturally occurring chemicals via the air breathed, the water drunk and the food eaten. Exposure also occurs in clinical settings. Naturally occurring chemicals ...

  17. Engaging Nature Aesthetically

    ERIC Educational Resources Information Center

    Kupfer, Joseph H.

    2003-01-01

    For the most part, most people appreciate nature as spectators. Some portion of a natural scene is viewed as if it were a painting or photograph. However, thinking of nature solely or chiefly as an aesthetic scene to be observed is unnecessarily limiting. Regarding natural phenomena as material for detached, pictorial observation overlooks the…

  18. The Nature of Natural Hazards Communication (Invited)

    NASA Astrophysics Data System (ADS)

    Kontar, Y. Y.

    2013-12-01

    Some of the many issues of interest to natural hazards professionals include the analysis of proactive approaches to the governance of risk from natural hazards and approaches to broaden the scope of public policies related to the management of risks from natural hazards, as well as including emergency and environmental management, community development and spatial planning related to natural hazards. During the talk we will present results of scientific review, analysis and synthesis, which emphasize same new trends in communication of the natural hazards theories and practices within an up-to-the-minute context of new environmental and climate change issues, new technologies, and a new focus on resiliency. The presentation is divided into five sections that focus on natural hazards communication in terms of education, risk management, public discourse, engaging the public, theoretical perspectives, and new media. It includes results of case studies and best practices. It delves into natural hazards communication theories, including diffusion, argumentation, and constructivism, to name a few. The presentation will provide information about: (1) A manual of natural hazards communication for scientists, policymakers, and media; (2) An up-to-the-minute context of environmental hazards, new technologies & political landscape; (3) A work by natural hazards scientists for geoscientists working with social scientists and communication principles; (4) A work underpinned by key natural hazards communication theories and interspersed with pragmatic solutions; (5) A work that crosses traditional natural hazards boundaries: international, interdisciplinary, theoretical/applied. We will further explore how spatial planning can contribute to risk governance by influencing the occupation of natural hazard-prone areas, and review the central role of emergency management in risk policy. The goal of this presentation is to contribute to the augmentation of the conceptual framework

  19. A Natural Love of Natural Products

    PubMed Central

    2008-01-01

    Recent research on the chemistry of natural products from the author’s group that led to the receipt of the ACS Ernest Guenther Award in the Chemistry of Natural Products is reviewed. REDOR NMR and synthetic studies established the T-taxol conformation as the bioactive tubulin-binding conformation, and these results were confirmed by the synthesis of compounds which clearly owed their activity or lack of activity to whether or not they could adopt the T-taxol conformation. Similar studies with the epothilones suggest that the current tubulin-binding model needs to be modified. Examples of natural products discovery and biodiversity conservation in Suriname and Madagascar are also presented, and it is concluded that natural products chemistry will continue to make significant contributions to drug discovery. PMID:18459734

  20. Nature's Nature: Ideas of Nature in Curricula for Environmental Education

    ERIC Educational Resources Information Center

    St Maurice, Henry

    2006-01-01

    Two contrasting sets of ideas about nature in environmental education are described. An analytical framework is developed from inter-disciplinary histories of ideas and used in evaluating a specific curriculum. In conclusion, some general implications are suggested for curricula in environmental education. [This article was reprinted from…

  1. Demonstrating Natural Selection

    ERIC Educational Resources Information Center

    Hinds, David S.; Amundson, John C.

    1975-01-01

    Describes laboratory exercises with chickens selecting their food from dyed and natural corn kernels as a method of demonstrating natural selection. The procedure is based on the fact that organisms that blend into their surroundings escape predation. (BR)

  2. Natural Gas Monthly

    EIA Publications

    2017-01-01

    Highlights activities, events, and analyses associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer related activities and underground storage data are also reported.

  3. Natural gas annual 1996

    SciTech Connect

    1997-09-01

    This document provides information on the supply and disposition of natural gas to a wide audience. The 1996 data are presented in a sequence that follows natural gas from it`s production to it`s end use.

  4. Fine Arts through Nature.

    ERIC Educational Resources Information Center

    Gentry, Carol

    1986-01-01

    Describes how high school students are involved in using natural materials found in the local environment for art projects. The materials used include wood, clay, and natural fibers. Provides photographs of ten students' projects. (JDH)

  5. Colours From Nature

    ERIC Educational Resources Information Center

    Simon, Wilma

    1974-01-01

    In reference to American Indian ceremonial art, the importance of using natural pigments is emphasized, since the superior color values of natural dyes better reflect religious and philosophical depth and meaning. (JC)

  6. Natural gas annual 1994

    SciTech Connect

    1995-11-17

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1994 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1990 to 1994 for each Census Division and each State. Annual historical data are shown at the national level.

  7. Natural gas annual 1995

    SciTech Connect

    1996-11-01

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1995 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1991 to 1995 for each Census Division and each State. Annual historical data are shown at the national level.

  8. Natural Gas Basics

    SciTech Connect

    2016-06-01

    Natural gas powers about 150,000 vehicles in the United States and roughly 22 million vehicles worldwide. Natural gas vehicles (NGVs) are a good choice for high-mileage fleets -- such as buses, taxis, and refuse vehicles -- that are centrally fueled or operate within a limited area or along a route with natural gas fueling stations. This brochure highlights the advantages of natural gas as an alternative fuel, including its domestic availability, established distribution network, relatively low cost, and emissions benefits.

  9. Natural Gas Basics

    SciTech Connect

    2016-06-08

    Natural gas powers about 150,000 vehicles in the United States and roughly 22 million vehicles worldwide. Natural gas vehicles (NGVs) are a good choice for high-mileage fleets -- such as buses, taxis, and refuse vehicles -- that are centrally fueled or operate within a limited area or along a route with natural gas fueling stations. This brochure highlights the advantages of natural gas as an alternative fuel, including its domestic availability, established distribution network, relatively low cost, and emissions benefits.

  10. Simple and rapid direct cloning and heterologous expression of natural product biosynthetic gene cluster in Bacillus subtilis via Red/ET recombineering

    PubMed Central

    Liu, Qingshu; Shen, Qiyao; Bian, Xiaoying; Chen, Hanna; Fu, Jun; Wang, Hailong; Lei, Ping; Guo, Zhaohui; Chen, Wu; Li, Dingjun; Zhang, Youming

    2016-01-01

    Heterologous expression of biosynthetic pathways is an important way to research and discover microbial natural products. Bacillus subtilis is a suitable host for the heterologous production of natural products from bacilli and related Firmicutes. Existing technologies for heterologous expression of large biosynthetic gene clusters in B. subtilis are complicated. Herein, we present a simple and rapid strategy for direct cloning based heterologous expression of biosynthetic pathways in B. subtilis via Red/ET recombineering, using a 5.2 kb specific direct cloning vector carrying homologous sequences to the amyE gene in B. subtilis and CcdB counterselection marker. Using a two-step procedure, two large biosynthetic pathways for edeine (48.3 kb) and bacillomycin (37.2 kb) from Brevibacillus brevis X23 and B. amyloliquefaciens FZB42, respectively, were directly cloned and subsequently integrated into the chromosome of B. subtilis within one week. The gene cluster for bacillomycin was successfully expressed in the heterologous host, although edeine production was not detectable. Compared with similar technologies, this method offers a simpler and more feasible system for the discovery of natural products from bacilli and related genera. PMID:27687863

  11. Learning in Nature

    ERIC Educational Resources Information Center

    Brody, Michael

    2005-01-01

    This paper traces the evolution of a theory of learning in nature in order to explain how people learn in natural settings. The intellectual roots of the theory in informal learning, cognition, affective development, experiential and meaningful learning are described and the synthesis into a comprehensive theory of learning in nature are…

  12. Nature in the City.

    ERIC Educational Resources Information Center

    Ferbert, Mary Lou

    1981-01-01

    Describes a science program developed by the Cleveland Museum of Natural History, "Nature in the City," in which students and teachers learn together about the natural community surrounding their school. Includes program's rationale, list of "adventures," and methods. Discusses strategies of Sherlock Holmes'"adventure" focusing on animal tracks…

  13. On nature and bioethics.

    PubMed

    Peterson, Paul Silas

    2010-01-01

    The account of nature and humanity's relationship to nature are of central importance for bioethics. The Scientific Revolution was a critical development in the history of this question and many contemporary accounts of nature find their beginnings here. While the innovative approach to nature going out of the seventeenth century was reliant upon accounts of nature from the early modern period, the Middle Ages, late-antiquity and antiquity, it also parted ways with some of the understandings of nature from these epochs. Here I analyze this development and suggests that some of the insights from older understandings of nature may be helpful for bioethics today, even if there can be no simple return to them.

  14. Natural gas annual 1997

    SciTech Connect

    1998-10-01

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1997 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1993 to 1997 for each Census Division and each State. Annual historical data are shown at the national level. 27 figs., 109 tabs.

  15. Natural gas monthly

    SciTech Connect

    Not Available

    1983-08-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. The NGM replaces three EIA reports previously published annually: Underground Natural Gas Storage in the United States; US Imports and Exports of Natural Gas; Main Line Sales of Natural Gas to Industrial Users. Some of the highlights are: marketed production of natural gas during June 1983 was estimated at 1307 billion cubic feet (Bcf), 178 Bcf (12.0 percent) below the June 1982 level; consumption of natural gas during June 1983 was an estimated 1060 Bcf, a decrease of 55 Bcf (4.9 percent) compared to June 1982 consumption; natural gas consumption in May 1983, compared to the previous May, was up 14.0 percent in the residential sector, up 7.9 percent in the commercial sector, and up 14.2 percent in the industrial sector; the volume of working gas in underground storage reservoirs at the end of June 1983 was 3.1 percent above the June 30, 1982 level; the average wellhead price of natural gas in April 1983 was $2.63 per thousand cubic feet (Mcf) compared to $2.35 per Mcf for April 1982; in June 1983, the US city average residential price for 100 therms of natural gas was $64.70 ($6.63 per Mcf), the comparable price in June 1982 was $54.80 ($5.62 per Mcf); the average wellhead (first sale) price for natural gas purchases projected for July 1983 by selected interstate pipeline companies was $2.72 per Mcf, in July 1982 the average price was $2.45 per Mcf.

  16. Island Natural Science School.

    ERIC Educational Resources Information Center

    Toronto Board of Education (Ontario).

    Prepared for students in grade six attending the Island Natural Science School, Toronto, Ontario, Canada, this booklet offers information and suggests activities in the areas of ecology, conservation, natural resources, and outdoor recreation. Introductory material describes island lore, its formation and significant features, followed by units of…

  17. Nature's Advice Book

    ERIC Educational Resources Information Center

    Mahlin, Kathryn; Robertson, Amy

    2005-01-01

    What do can people learn from the world around them? Can a tree really teach something about life? Many times teachers provide students with facts about nature but fail to consider what one can learn from the natural world around them. After many months of exploring various ecosystems such as the prairie, rain forest, and desert, one of the…

  18. Natural Resources Bibliography.

    ERIC Educational Resources Information Center

    Hoadley, Irene Braden

    This bibliography presents a modern definition of the conceptual framework from which to view natural resources, and affords access to information which examines resources from the social scientists point of view. It presents five broad divisions of activity or variables which include (1) Natural and Human Resources, (2) Epistomological and…

  19. Natural Language Information Retrieval.

    ERIC Educational Resources Information Center

    Strzalkowski, Tomek

    1995-01-01

    Describes an information retrieval system in which advanced natural language processing is used to enhance the effectiveness of term-based document retrieval by preprocessing the documents; discovering interterm dependencies and build a conceptual hierarchy specific to database domain; and processing the user's natural language requests into…

  20. Natural Language Sourcebook

    DTIC Science & Technology

    1990-01-01

    Discussion Lemon has two meanings. In (1) it means a poorly made car. In (2) it means a small, sour , yellow fruit. Usually a frame or script is used... dough " has different meanings in the cooking and bank robbery frames. front end: a natural language system that accepts natural language input and/or

  1. On Teaching Natural Law.

    ERIC Educational Resources Information Center

    Forte, David F.

    1978-01-01

    A brief look at Columbia, Harvard, and Notre Dame law schools shows that the American tradition in teaching natural law has not been strong. The value of teaching natural law is discussed, a separate course or seminar is seen as the most effective option, and a selection of available sources for such a course is appended. (JMD)

  2. Modeling Natural Selection

    ERIC Educational Resources Information Center

    Bogiages, Christopher A.; Lotter, Christine

    2011-01-01

    In their research, scientists generate, test, and modify scientific models. These models can be shared with others and demonstrate a scientist's understanding of how the natural world works. Similarly, students can generate and modify models to gain a better understanding of the content, process, and nature of science (Kenyon, Schwarz, and Hug…

  3. Introduction to Exploring Nature

    ERIC Educational Resources Information Center

    Early Childhood Today, 2006

    2006-01-01

    Children are fascinated with the world of nature. From the tiniest of seeds to the highest of birds, they wonder "Why?" "How?" and "What can I do with it?" This paper provides intriguing nature activities that provide a solid starting point for expanding children's thinking and learning. Through these activities, children will be building skills…

  4. Birds. Nature Discovery I.

    ERIC Educational Resources Information Center

    Stone, Sally F.

    The birds of New England and their particular habitats are explored in this guide which is part of a series of Nature Discovery publications. The materials are designed to directly supplement the natural science curricula and to complement other subject areas including social studies, language arts, music, and art. The program is designed for…

  5. Nature of Science Is...

    ERIC Educational Resources Information Center

    Lederman, Judith Sweeney; Lederman, Norman G.

    2005-01-01

    The phrase "nature of science" refers to the characteristics of scientific knowledge that necessarily result from the scientific investigations that scientists conduct to develop knowledge. Yet, these characteristics are assumed by many to be "difficult" to teach. Not so. Many important aspects of nature of science can be directly linked to…

  6. Nature Foil Reliefs

    ERIC Educational Resources Information Center

    Lane, Shaw J.

    2012-01-01

    Nature has always been a source of inspiration for artists across the centuries. Artists such as Leonardo da Vinci, Georgia O'Keeffe, Ansel Adams, and Andy Goldsworthy all drew inspiration for their work from nature. Seeds come from the dried pods, which when planted and cared for, bear fruit. In this article, the author describes how her…

  7. Natural gas monthly

    SciTech Connect

    Not Available

    1982-12-01

    This report presents data on the supply and disposition of natural gas in the USA during August 1982, as well as data on production, storage, imports, exports, and consumption. Selected data are also presented on the activities of the major interstate pipeline companies. Marketed production of natural gas decreased 18.2% during August 1982, compared to August 1981, from 1706 billion cubic feet (Bcf) to 1471 Bcf. Consumption during the same period declined as well, from 1314 Bcf to 1153 Bcf. Commencing with this issue of the Natural Gas Monthly (NGM), estimates of marketed production are provided for two more recent months, September and October. Volumes of natural gas in storage continue to run slightly ahead of year-ago levels. The volume of natural gas purchased from producers and imported by major interstate natural gas pipeline companies continues to decline. In August 1981, 864 Bcf were purchased from producers, compared to 793 Bcf in August 1982. Imports during the same period declined from 62 Bcf to 46 Bcf. Applications for determination of a maximum lawful price under the Natural Gas Policy Act (NGPA) showed a significant increase between September and October 1982. The increase occurred principally for Section 103 classification wells (new onshore production wells), and for Section 107 classification wells (high-cost natural gas).

  8. Natural gas monthly

    SciTech Connect

    Not Available

    1983-04-01

    This document highlights activities, events, and analysis results of interest to public and private sector organizations associated with natural gas industry operations. Data highlights: (1) Marketed production of natural gas during February 1983 was estimated at 1387 billion cubic feet (Bcf), 178 Bcf (11.4 percent) below the February 1982 level; (2) Consumption of natural gas during February 1983 was an estimated 1709 Bcf, a decrease of 258 Bcf (13.1 percent) compared to February 1982 consumption; (3) Consumption declined in all market sectors in January 1983 compared to January 1982; (4) The volume of working gas in underground storage reservoirs at the end of February 1983 was 31.7 percent above the February 28, 1982 level; (5) The average wellhead price of natural gas in December 1982 was $2.56 per thousand cubic feet (Mcf). In December 1981 the average was $2.16 per Mcf; (6) In February 1983, the US city average residential price for 100 therms of natural gas was $59.99; and (7) The average wellhead (first sale) price for natural gas purchases projected for March 1983 by selected interstate pipeline companies was $2.79 per Mcf. The feature article in this issue is entitled Recent Trends in Natural Gas Well Costs. Information is presented under the headings: industry overview, explanatory notes, data sources, and selected recurring natural gas and related reports. 5 figures, 24 tables. (DMC)

  9. Nature Experience and Education

    ERIC Educational Resources Information Center

    Rathunde, Kevin

    2013-01-01

    Kevin Rathunde turns his research lens to the task of finding out the relevance of the natural world, its impact on adolescent motivation, and its positive sustaining of concentration and focus. He cites "disembodiment and denaturing" as needing to be countered by contact with nature, leading to higher creativity, less drudgery, and more…

  10. Naturally occurring insecticides.

    PubMed Central

    Soloway, S B

    1976-01-01

    Naturally occurring insecticides are abundant and varied in their effects, though but a few are articles of commerce. Even for these, pyrethrum, nicotine, rotenone, hellebore, ryania, and sabadilla, there is a paucity of information on mammalian toxicology and environmental effects. In general, these materials are characterized favorably by low acute toxicity and ready dissipation in nature. Unfavorable aspects of natural insecticides are the contained mixture of active and inactive components and the low active ingredient content on a crop yield basis pointing to a high unit cost. Natural insecticides can serve additionally as leads to unnatural mimics, of which the commercially successful synthetic pyrethroids are prime examples. The chemical nature, relationship of insecticidal activity to chemical structure, occurrence, production, and utilization, registered uses, metabolism, and insect and mammalian toxicity are reviewed. PMID:789058

  11. Thermoacoustic natural gas liquefier

    SciTech Connect

    Swift, G.; Gardner, D.; Hayden, M.; Radebaugh, R.; Wollan, J.

    1996-07-01

    This is the final report of a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project sought to develop a natural-gas-powered natural-gas liquefier that has absolutely no moving parts and requires no electrical power. It should have high efficiency, remarkable reliability, and low cost. The thermoacoustic natural-gas liquefier (TANGL) is based on our recent invention of the first no-moving-parts cryogenic refrigerator. In short, our invention uses acoustic phenomena to produce refrigeration from heat, with no moving parts. The required apparatus comprises nothing more than heat exchangers and pipes, made of common materials, without exacting tolerances. Its initial experimental success in a small size lead us to propose a more ambitious application: large-energy liquefaction of natural gas, using combustion of natural gas as the energy source. TANGL was designed to be maintenance-free, inexpensive, portable, and environmentally benign.

  12. Agriculture: Natural Events and Disasters

    EPA Pesticide Factsheets

    Natural Events and DiasastersInformation on Natural Events and Disasters. Every year natural disasters, such as hurricanes, floods, fires, earthquakes, and tornadoes, challenge agricultural production.

  13. On nature's scaling effects

    NASA Technical Reports Server (NTRS)

    Wilkins, Dick J.

    1994-01-01

    This presentation afforded the opportunity to look back in the literature to discover scaling effects in nature that might be relevant to composites. Numerous examples were found in nature's approaches to wood, teeth, horns, leaves, eggs, feathers, etc. Nature transmits tensile forces rigidly with cohesive bonds, while dealing with compression forces usually through noncompressible hydraulics. The optimum design scaling approaches for aircraft were also reviewed for comparison with similitude laws. Finally, some historical evidence for the use of Weibull scaling in composites was reviewed.

  14. Living in cities, naturally.

    PubMed

    Hartig, Terry; Kahn, Peter H

    2016-05-20

    Natural features, settings, and processes in urban areas can help to reduce stress associated with urban life. In this and other ways, public health benefits from, street trees, green roofs, community gardens, parks and open spaces, and extensive connective pathways for walking and biking. Such urban design provisions can also yield ecological benefits, not only directly but also through the role they play in shaping attitudes toward the environment and environmental protection. Knowledge of the psychological benefits of nature experience supports efforts to better integrate nature into the architecture, infrastructure, and public spaces of urban areas.

  15. Is image steganography natural?

    PubMed

    Martín, Alvaro; Sapiro, Guillermo; Seroussi, Gadiel

    2005-12-01

    Steganography is the art of secret communication. Its purpose is to hide the presence of information, using, for example, images as covers. We experimentally investigate if stego-images, bearing a secret message, are statistically "natural." For this purpose, we use recent results on the statistics of natural images and investigate the effect of some popular steganography techniques. We found that these fundamental statistics of natural images are, in fact, generally altered by the hidden "nonnatural" information. Frequently, the change is consistently biased in a given direction. However, for the class of natural images considered, the change generally falls within the intrinsic variability of the statistics, and, thus, does not allow for reliable detection, unless knowledge of the data hiding process is taken into account. In the latter case, significant levels of detection are demonstrated.

  16. Make a Nature Trail

    ERIC Educational Resources Information Center

    Johnson, Janice K.

    1973-01-01

    Discusses the planning, construction, use, and maintenance of a nature trail. Ideal for demonstrating interrelationships between plants and animals, conservation practices, wildlife management, plant succession, forestry, geologic features and other scientific phenomena. (JR)

  17. Natural radioactivity. Proceedings

    SciTech Connect

    de Bettencourt, A.O.; Galvao, J.P.; Lowder, W.; Olast, M.; Sinnaeve, J.

    1988-12-31

    This volume provides the Proceedings of the Fourth International Symposium on the Natural Radiation Environment held in Lisbon, Portugal December 7--11, 1987. Individual papers of the symposium are abstracted and indexed for the database.

  18. Web life: Ask Nature

    NASA Astrophysics Data System (ADS)

    2012-11-01

    Ask Nature is a site devoted to biomimicry, an interdisciplinary field in which practitioners study how animals and plants solve problems, and then use those solutions to develop better human technologies.

  19. Tifft Farm Nature Preserve.

    ERIC Educational Resources Information Center

    Benjamin, Thomas B.; Gannon, David J.

    1980-01-01

    Described are the creation, development, activities, and programs of Tifft Farm, a 264-acre nature preserve and environmental education center in Buffalo, New York, constructed on a sanitary landfill. (BT)

  20. Lesson "Balance in Nature

    NASA Astrophysics Data System (ADS)

    Chapanova, V.

    2012-04-01

    Lesson "Balance in Nature" This simulation game-lesson (Balance in Nature) gives an opportunity for the students to show creativity, work independently, and to create models and ideas. It creates future-oriented thought connected to their experience, allowing them to propose solutions for global problems and personal responsibility for their activities. The class is divided in two teams. Each team chooses questions. 1. Question: Pollution in the environment. 2. Question: Care for nature and climate. The teams work on the chosen tasks. They make drafts, notes and formulate their solutions on small pieces of paper, explaining the impact on nature and society. They express their points of view using many different opinions. This generates alternative thoughts and results in creative solutions. With the new knowledge and positive behaviour defined, everybody realizes that they can do something positive towards nature and climate problems and the importance of individuals for solving global problems is evident. Our main goal is to recover the ecological balance, and everybody explains his or her own well-grounded opinions. In this work process the students obtain knowledge, skills and more responsible behaviour. This process, based on his or her own experience, dialogue and teamwork, helps the participant's self-development. Making the model "human↔ nature" expresses how human activities impact the natural Earth and how these impacts in turn affect society. Taking personal responsibility, we can reduce global warming and help the Earth. By helping nature we help ourselves. Teacher: Veselina Boycheva-Chapanova " Saint Patriarch Evtimii" Scholl Str. "Ivan Vazov"-19 Plovdiv Bulgaria

  1. Natural Resource Management Plan

    SciTech Connect

    Green, T.; Schwager, K.

    2016-10-01

    This comprehensive Natural Resource Management Plan (NRMP) for Brookhaven National Laboratory (BNL) was built on the successful foundation of the Wildlife Management Plan for BNL, which it replaces. This update to the 2003 plan continues to build on successes and efforts to better understand the ecosystems and natural resources found on the BNL site. The plan establishes the basis for managing the varied natural resources located on the 5,265-acre BNL site, setting goals and actions to achieve those goals. The planning of this document is based on the knowledge and expertise gained over the past 15 years by the Natural Resources management staff at BNL in concert with local natural resource agencies including the New York State Department of Environmental Conservation, Long Island Pine Barrens Joint Planning and Policy Commission, The Nature Conservancy, and others. The development of this plan works toward sound ecological management that not only benefits BNL’s ecosystems but also benefits the greater Pine Barrens habitats in which BNL is situated. This plan applies equally to the Upton Ecological and Research Reserve (Upton Reserve). Any difference in management between the larger BNL area and the Upton Reserve are noted in the text.

  2. Blackouts and natural risks

    NASA Astrophysics Data System (ADS)

    Danihelka, P.; Paldusová, E.; Dobeš, P.

    2009-04-01

    "Blackout" has become the common definition for the situation when electricity supply and demand are not balanced and security of supply fails. These failures have many impacts besides the lights going out, but this term is used commonly. Blackouts have drastic impacts for the society on whole and its citizens and some of them can influence big areas and last for long period, so the consequences are catastrophic. Even if at the European scale, the large extend blackouts are supposed to be exceptional, real frequency is relatively high, approximately once per two years. According to statistics, blackouts are often caused by natural causes, especially lightning. An example of lightning caused blackout is New York blackout 1977, leading to the stand-by of nuclear power plant Indian Point and with overall cost more than 300 mil. USD. There is a clear a distinction between those blackouts caused by nature and those that were caused by other faults. Usually, the nature-caused disturbances as Canada 1988, Sweden 2005 and France 1999, stay inside one country. However, their duration can extend to several weeks, and thus the costs of the interruptions and social impacts are high. Blackouts of only technologic and/or anthropogenic origin are frequently shorter, but may concern more end-users, when cascading from one country to another. Lightning is not the only natural event causing blackouts. Eighteen various case studies of blackout caused by natural events different then lightning were studied and following natural phenomenon found as a root causes: 1x forest fire, 1x snow calamity, 1x ice storm, 1x landslide, 1x high temperature, 1x geomagnetic storm, 2x earthquake, 2x inundation, 2x contact of line with trees, 6x storm (wind, hurricane…). We can conclude, that natural event are frequent cause of blackout of medium or large extend and this phenomena should be studied more in details. This contribution was supported by Ministry of Environment of the Czech Republic.

  3. Natural Dietary Phytosterols.

    PubMed

    Racette, Susan B; Lin, Xiaobo; Ma, Lina; Ostlund, Richard E

    2015-01-01

    Most clinical phytosterol studies are performed by adding purified supplements to smaller phytosterol amounts present in the natural diet. However, natural dietary phytosterols themselves may also have important effects on cholesterol metabolism. Epidemiological work using food frequency questionnaires to estimate dietary intake suggest that extremes of normal consumption may be associated with 3-14% changes in LDL cholesterol. Standardized food databases do not have enough phytosterol values to allow calculation of phytosterol intake for individuals outside of specialized studies. Natural diets contain phytosterol amounts ranging from less than 60 mg/2000 kcal to over 500 mg/2000 kcal. Physiological studies in which whole body cholesterol metabolism is investigated show large effects of natural dietary phytosterols on cholesterol absorption efficiency, cholesterol biosynthesis and cholesterol excretion which exceed the magnitude of changes in LDL cholesterol. The dual effects of natural phytosterols on both LDL-C and whole body cholesterol metabolism need to be considered in relating them to potential protection from coronary heart disease risk.

  4. Natural competence for transformation.

    PubMed

    Blokesch, Melanie

    2016-11-07

    While most molecular biologists are familiar with the artificial transformation of bacteria in the context of laboratory cloning experiments, natural competence for transformation refers to a specific physiological state in which prokaryotes are able to take up genetic material from their surroundings. Occasionally, such absorbed DNA is recombined into the organism's own genome, resulting in natural transformation (Figure 1). As a consequence, natural competence for transformation is considered a primary mode of horizontal gene transfer (HGT) in prokaryotes, together with conjugation (direct cell to cell transfer of DNA via a specialized conjugal pilus) and phage transduction (DNA transfer mediated by viruses). HGT plays a major role in bacterial evolution, and past research has demonstrated that HGT, including natural competence for transformation, contributes to the emergence of pathogens and the spread of virulence factors. Indeed, Frederick Griffith discovered natural competence for transformation in 1928 while he was investigating the exchange of pathogenic traits in pneumococci. Due to the increase in the abundance and spread of multidrug-resistant microbes, research on HGT is even more important today than ever before.

  5. Natural flow wing

    NASA Technical Reports Server (NTRS)

    Wood, Richard M. (Inventor); Bauer, Steven X. S. (Inventor)

    1992-01-01

    The invention is a natural flow wing and a method for constructing the same. The method comprises contouring a three-dimensional upper surface and a three-dimensional lower surface of the natural flow wing independently of one another into a prescribed shape. Experimental data and theoretical analysis show that flow and pressure-loading over an upper surface of a wing tend to be conical about an apex of the wing, producing favorable and unfavorable regions of performance based on drag. The method reduces these unfavorable regions by shaping the upper surface such that the maximum thickness near a tip of the natural flow wing moves aft, thereby, contouring the wing to coincide more closely with the conical nature of the flow on the upper surface. Nearly constant compressive loading characterizes the flow field over a lower surface of the conventional wing. Magnitude of these compressive pressures on the lower surface depends on angle of attack and on a streamwise curvature of the lower surface of the wing and not on a cross-sectional spanwise curvature. The method, thereby, shapes the lower surface to create an area as large as possible with negative slopes. Any type of swept wing may be used to obtain the final, shaped geometry of the upper and lower surfaces of the natural flow wing.

  6. Natural photonic crystals

    NASA Astrophysics Data System (ADS)

    Vigneron, Jean Pol; Simonis, Priscilla

    2012-10-01

    Photonic structures appeared in nature several hundred millions years ago. In the living world, color is used for communication and this important function strongly impacts the individual chances of survival as well as the chances to reproduce. This has a statistical influence on species populations. Therefore, because they are involved in evolution, natural color-generating structures are - from some point of view - highly optimized. In this short review, a survey is presented of the development of natural photonic crystal-type structures occurring in insects, spiders, birds, fishes and other marine animals, in plants and more, from the standpoint of light-waves propagation. One-, two-, and three-dimensional structures will be reviewed with selected examples.

  7. Nature/culture/seawater.

    PubMed

    Helmreich, Stefan

    2011-01-01

    Seawater has occupied an ambiguous place in anthropological categories of "nature" and "culture." Seawater as nature appears as potentiality of form and uncontainable flux; it moves faster than culture - with culture frequently figured through land-based metaphors - even as culture seeks to channel water's (nature's) flow. Seawater as culture manifests as a medium of pleasure, sustenance, travel, disaster. I argue that, although seawater's qualities in early anthropology were portrayed impressionistically, today technical, scientific descriptions of water's form prevail. For example, processes of globalization - which may also be called "oceanization" - are often described as "currents," "flows," and "circulations." Examining sea-set ethnography, maritime anthropologies, and contemporary social theory, I propose that seawater has operated as a “theory machine” for generating insights about human cultural organization. I develop this argument with ethnography from the Sargasso Sea and in the Sea Islands. I conclude with a critique of appeals to water's form in social theory.

  8. Natural environment analysis

    NASA Technical Reports Server (NTRS)

    Frost, W.

    1985-01-01

    The influence of terrain features on wind loading of the space shuttle while on the launch pad, or during early liftoff, was investigated both qualitatively and quantitatively. The climatology and meteorology producing macroscale wind patterns and characteristics for the Vandenburg Air Force Base launch site are described. Field test data are analyzed, and the nature and characteristic of flow disturbances due to the various terrain features, both natural and man-made, are reviewed. The magnitude of these wind loads are estimated. Finally, effects of turbulence are discussed. It is concluded that the influence of complex terrain can create significant wind loading on the vehicle.

  9. Natural language modeling

    SciTech Connect

    Sharp, J.K.

    1997-11-01

    This seminar describes a process and methodology that uses structured natural language to enable the construction of precise information requirements directly from users, experts, and managers. The main focus of this natural language approach is to create the precise information requirements and to do it in such a way that the business and technical experts are fully accountable for the results. These requirements can then be implemented using appropriate tools and technology. This requirement set is also a universal learning tool because it has all of the knowledge that is needed to understand a particular process (e.g., expense vouchers, project management, budget reviews, tax, laws, machine function).

  10. Natural Cycles, Gases

    NASA Technical Reports Server (NTRS)

    Douglass, Anne R.; Jackman, Charles H.; Rood, R. B.; Aikin, A. C.; Stolarski, R. S.; Mccormick, M. P.; Fahey, David W.

    1992-01-01

    The major gaseous components of the exhaust of stratospheric aircraft are expected to be the products of combustion (CO2 and H2O), odd nitrogen (NO, NO2 HNO3), and products indicating combustion inefficiencies (CO and total unburned hydrocarbons). The species distributions are produced by a balance of photochemical and transport processes. A necessary element in evaluating the impact of aircraft exhaust on the lower stratospheric composition is to place the aircraft emissions in perspective within the natural cycles of stratospheric species. Following are a description of mass transport in the lower stratosphere and a discussion of the natural behavior of the major gaseous components of the stratospheric aircraft exhaust.

  11. Enhance Nature Exploration with Technology

    ERIC Educational Resources Information Center

    Holloway, Patricia; Mahan, Carol

    2012-01-01

    Kids and nature seem like a natural combination, but what was natural a generation ago is different today. Children are spending less time outdoors but continue to need nature for their physical, emotional, and mental development. This fact has led author Richard Louv to suggest that today's children are suffering from "nature-deficit disorder"…

  12. Nature as Inspiration

    ERIC Educational Resources Information Center

    Tank, Kristina; Moore, Tamara; Strnat, Meg

    2015-01-01

    This article describes the final lesson within a seven-day STEM and literacy unit that is part of the Picture STEM curriculum (pictureSTEM. org) and uses engineering to integrate science and mathematics learning in a meaningful way (Tank and Moore 2013). For this engineering challenge, students used nature as a source of inspiration for designs to…

  13. Picturing the Natural Environment

    ERIC Educational Resources Information Center

    Johnson, Phyllis Scott

    2011-01-01

    Around Scout Island Education Center, a site used by schools in Fresno County to explore the area's natural environment, a total of 200 cylinder-shaped concrete stools display tiles representing small mammals, flying insects, birds, wildflowers, and more. Twenty sets have been created by elementary, middle, and high-school art students as part of…

  14. Demystifying Nature of Science

    ERIC Educational Resources Information Center

    Lederman, Judith; Bartels, Selina; Lederman, Norman; Gnanakkan, Dionysius

    2014-01-01

    With the emergence of the "Next Generation Science Standards" ("NGSS"; NGSS Lead States 2013), it is apparent that teaching and learning about nature of science (NOS) continues to be an important goal of science education for all K-12 students. With this emphasis on NOS, early childhood teachers are asking how to design…

  15. Nature, Education and Things

    ERIC Educational Resources Information Center

    Rømer, Thomas Aastrup

    2013-01-01

    In this essay it is argued that the educational philosophy of John Dewey gains in depth and importance by being related to his philosophy of nature, his metaphysics. The result is that any experiental process is situated inside an event, an existence, a thing, and I try to interpret this "thing" as schools or major cultural events such…

  16. The Nature of Atoms.

    ERIC Educational Resources Information Center

    Holden, Alan

    This monograph was written for the purpose of presenting physics to college students who are not preparing for careers in physics. It deals with the nature of atoms, and treats the following topics: (1) the atomic hypothesis, (2) the chemical elements, (3) models of an atom, (4) a particle in a one-dimensional well, (5) a particle in a central…

  17. Natural Resources Education Notebook.

    ERIC Educational Resources Information Center

    Weber, Eldon C.

    This notebook was developed cooperatively by the United States Soil Conservation Service and Iowa State University to be used by teachers in providing instruction regarding certain aspects of natural resources. It includes four sections which provide: (1) an instructional plan about the conservation provisions of the 1985 Food Security Act; (2) an…

  18. Designing Nature's Way

    ERIC Educational Resources Information Center

    Fisher, Diane

    2005-01-01

    In the case of cars and other engineered objects, humans go about the design process in a very intentional way. They pretty much know what they are aiming for. The activity described in this article demonstrates how a computer can simulate biological evolution and the laws of natural selection. The article is divided into the following sections:…

  19. Nitrogen and nature.

    PubMed

    Vitousek, Peter M; Hättenschwiler, Stephan; Olander, Lydia; Allison, Steven

    2002-03-01

    Anthropogenic changes to the global N cycle are important in part because added N alters the composition, productivity, and other properties of many natural ecosystems substantially. Why does added N have such a large impact? Why is N in short supply in so many natural ecosystems? Processes that slow the cycling of N relative to other elements and processes that control ecosystem-level inputs and outputs of N could cause N supply to limit the dynamics of ecosystems. We discuss stoichiometric differences between terrestrial plants and other organisms, the abundance of protein-precipitating plant defenses, and the nature of the C-N bond in soil organic matter as factors that can slow N cycling. For inputs, the energetic costs of N fixation and their consequences, the supply of nutrients other than N, and preferential grazing on N-fixers all could constrain the abundance and/or activity of biological N-fixers. Together these processes drive and sustain N limitation in many natural terrestrial ecosystems.

  20. The Natural Learning Process

    ERIC Educational Resources Information Center

    Criss, Ellen

    2008-01-01

    Teacher-educator and researcher Daniel L. Kohut suggests in "Musical Performance: Learning Theory and Pedagogy" that there are many problems that result from the way music teachers often teach. Most teachers focus on the process, not the goal. The Natural Learning Process that Kohut advocates is the same process that young children use when they…

  1. Reinventing Natural Selection

    ERIC Educational Resources Information Center

    Geraedts, Caspar L.; Boersma, Kerst Th.

    2006-01-01

    Although many research studies report students' Lamarckian misconceptions, only a few studies present learning and teaching strategies that focus on the successful development of the concept of natural selection. The learning and teaching strategy for upper secondary students (aged 15-16) presented in this study conducted in The Netherlands is…

  2. Natural Resources Management Program

    DTIC Science & Technology

    1989-01-24

    Program, activity, or opportunity dependent on the natural environment. Examples are hunting, fishing, trapping, picnick- ing, birdwatching , off-road...fair market value. d. Planned forest products sales shall continue on land reported as excess until actual disposal or transfer occurs. When forested

  3. Natural generalized mirage mediation

    NASA Astrophysics Data System (ADS)

    Baer, Howard; Barger, Vernon; Serce, Hasan; Tata, Xerxes

    2016-12-01

    In the supersymmetric scenario known as mirage mediation (MM), the soft supersymmetry (SUSY) breaking terms receive comparable anomaly-mediation and moduli-mediation contributions leading to the phenomenon of mirage unification. The simplest MM SUSY breaking models which are consistent with the measured Higgs mass and sparticle mass constraints are strongly disfavored by fine-tuning considerations. However, while MM makes robust predictions for gaugino masses, the scalar sector is quite sensitive to specific mechanisms for moduli stabilization and potential uplifting. We suggest here a broader setup of generalized mirage mediation (GMM), where heretofore discrete parameters are allowed as continuous to better parametrize these other schemes. We find that natural SUSY spectra consistent with both the measured value of mh as well as LHC lower bounds on superpartner masses are then possible. We explicitly show that models generated from natural GMM may be beyond the reach of even high-luminosity LHC searches. In such a case, the proposed International Linear e+e- Collider will be required for natural SUSY discovery via higgsino pair production reactions. We also outline prospects for detection of higgsino-like WIMPs from natural GMM.

  4. A Natural Integration

    ERIC Educational Resources Information Center

    Coskie, Tracy; Hornof, Michelle; Trudel, Heidi

    2007-01-01

    A five-week study taught students how to write a field guide that identified the plants in a small wooded area they passed through on their way to their school playground. By creating this authentic genre of science writing, students came to understand and care for the natural world in their immediate environment. They also developed important…

  5. The Nature of Evolution

    ERIC Educational Resources Information Center

    Alles, David L.

    2005-01-01

    The nature of evolution, the historical change in the universe, and the change that is caused by the workings of the dynamic processes at the smallest and largest scales are studied. It is viewed that the cumulative change in the historical systems is caused by evolution, which is a type of causal relationship and evolutionary processes could be…

  6. Natural Language Generation,

    DTIC Science & Technology

    1986-02-01

    modified with adverbs or adjectives, or elaborated by subordinated clauses. The natural recourse in this situation is to use a phrasal lexicon. This notion...Representation of Grammatical Relations, MIT Press, Cambridge, Mass., 1984. 171 G. Brown, Some Problems in German to English Machine Translation, MIT LCS TR 142

  7. The Nature of Diamonds

    NASA Astrophysics Data System (ADS)

    Harlow, George E.

    1997-10-01

    The paragon of physical perfection and a sparkling example of Earth's forces at work, the diamond has fascinated all realms of society, from starlets to scientists. The Nature of Diamonds is a comprehensive look at nature's most coveted gem. A handsome, large-format book, The Nature of Diamonds is an authoritative and richly-illustrated tribute to the diamond. Leading geologists, gemologists, physicists, and cultural observers cover every facet of the stone, from its formation in the depths of the Earth, its ascent to the surface, and its economic, regal, social, and technological roles. Cutting-edge research takes the reader to the frontiers of diamond exploration and exploitation, from the Arctic wastes to the laboratories where diamonds are created for massive road shredders that rip up and then re-create superhighways. Here also is an overview of cutting, from the rough stones in Roman rings to the highly-faceted stones we see today, and a glimpse into the business of diamonds. Finally, The Nature of Diamonds chronicles scientific and cultural history and explores the diamond as both a sacred and a social symbol, including a picture history of betrothal rings. Wide-ranging illustrations explain the geology of diamonds, chart the history of mining from its origins in India and Brazil through the diamond rush in South Africa and today's high-tech enterprises, and capture the brilliance and beauty of this extraordinary gem. _

  8. Radioactivity: A Natural Phenomenon.

    ERIC Educational Resources Information Center

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  9. Natural fracture systems studies

    SciTech Connect

    Lorenz, J.C.; Warpinski, N.R.

    1992-09-01

    The objectives of this program are (1) to develop a basinal-analysis methodology for natural fracture exploration and exploitation, and (2) to determine the important characteristics of natural fracture systems for use in completion, stimulation, and production operations. Natural-fracture basinal analysis begins with studies of fractures in outcrop, core and logs in order to determine the type of fracturing and the relationship of the fractures to the lithologic environment. Of particular interest are the regional fracture systems that are pervasive in western US tight sand basins. A Methodology for applying this analysis is being developed, with the goal of providing a structure for rationally characterizing natural fracture systems basin-wide. Such basin-wide characterizations can then be expanded and supplemented locally, at sites where production may be favorable. Initial application of this analysis is to the Piceance basin where there is a wealth of data from the Multiwell Experiment (MWX), DOE cooperative wells, and other basin studies conducted by Sandia, CER Corporation, and the USGS (Lorenz and Finley, 1989, Lorenz et aI., 1989, and Spencer and Keighin, 1984). Such a basinal approach has been capable of explaining the fracture characteristics found throughout the southern part of the Piceance basin and along the Grand Hogback.

  10. Picturing the Natural World

    ERIC Educational Resources Information Center

    Salia, Hannah

    2011-01-01

    How is the natural environment in the neighborhood representative of the larger biosphere in which people live? Studying the local birds and flora of the Pacific Northwest in the context of the local parks and ponds provided a rich opportunity for third-grade students at St. Thomas School in Medina, Washington, to explore and learn about…

  11. Gaia and natural selection

    NASA Astrophysics Data System (ADS)

    Lenton, Timothy M.

    1998-07-01

    Evidence indicates that the Earth self-regulates at a state that is tolerated by life, but why should the organisms that leave the most descendants be the ones that contribute to regulating their planetary environment? The evolving Gaia theory focuses on the feedback mechanisms, stemming from naturally selected traits of organisms, that could generate such self-regulation.

  12. Nature's engines: active matter

    NASA Astrophysics Data System (ADS)

    Yeomans, Julia M.

    2017-03-01

    Active materials, bacteria, molecular motors, and self-propelled colloids, continuously transform chemical energy from the environment to mechanical work. Dense active matter, from layers of cells to flocks of birds, self-assembles into intricate patterns. Nature's engines are complex and efficient, and we would like to exploit her ideas to fabricate nano-machines.

  13. A Natural Hazards Workbook.

    ERIC Educational Resources Information Center

    Kohler, Fred

    This paper discusses the development of and provides examples of exercises from a student workbook for a college-level course about natural hazards. The course is offered once a year to undergraduates at Western Illinois University. Students are introduced to 10 hazards (eight meteorological plus earthquakes and volcanoes) through slides, movies,…

  14. Natural Gas Annual

    EIA Publications

    2016-01-01

    Provides information on the supply and disposition of natural gas in the United States. Production, transmission, storage, deliveries, and price data are published by state for the current year. Summary data are presented for each state for the previous 5 years.

  15. A Biospheric Natural History.

    ERIC Educational Resources Information Center

    Thomashow, Mitchell

    2001-01-01

    A group of Maine birdwatchers recognizes that the presence or absence of migrating songbirds is related to complex biospheric patterns. For schoolchildren, community groups, and environmental scientists, such local natural history observations can be a pathway to perceiving and understanding global ecological change and then to developing…

  16. Saving Natural Inflation

    SciTech Connect

    Croon, Djuna; Sanz, Verónica E-mail: v.sanz@sussex.ac.uk

    2015-02-01

    Slow-roll inflation requires the inflaton field to have an exceptionally flat potential, which combined with measurements of the scale of inflation demands some degree of fine-tuning. Alternatively, the flatness of the potential could be due to the inflaton's origin as a pseudo-Goldstone boson, as in Natural Inflation. Alas, consistency with Planck data places the original proposal of Natural Inflation in a tight spot, as it requires a trans-Planckian excursion of the inflaton. Although one can still tune the renormalizable potential to sub-Planckian values, higher order corrections from quantum gravity or sources of breaking of the Goldstone symmetry would ruin the predictivity of the model. In this paper we show how in more realistic models of Natural Inflation one could achieve inflation without a trans-Planckian excursion of the field. We show how a variant of Extra-natural inflation with bulk fermions can achieve the desired goal and discuss its four-dimensional duals. We also present a new type of four dimensional models inspired in Little Higgs and Composite Higgs models which can lead to sub-Planckian values of the inflaton field.

  17. Natural hazards science strategy

    USGS Publications Warehouse

    Holmes, Jr., Robert R.; Jones, Lucile M.; Eidenshink, Jeffery C.; Godt, Jonathan W.; Kirby, Stephen H.; Love, Jeffrey J.; Neal, Christina A.; Plant, Nathaniel G.; Plunkett, Michael L.; Weaver, Craig S.; Wein, Anne; Perry, Suzanne C.

    2012-01-01

    The mission of the U.S. Geological Survey (USGS) in natural hazards is to develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation. The costs and consequences of natural hazards can be enormous, and each year more people and infrastructure are at risk. USGS scientific research - founded on detailed observations and improved understanding of the responsible physical processes - can help to understand and reduce natural hazard risks and to make and effectively communicate reliable statements about hazard characteristics, such as frequency, magnitude, extent, onset, consequences, and where possible, the time of future events. To accomplish its broad hazard mission, the USGS maintains an expert workforce of scientists and technicians in the earth sciences, hydrology, biology, geography, social and behavioral sciences, and other fields, and engages cooperatively with numerous agencies, research institutions, and organizations in the public and private sectors, across the Nation and around the world. The scientific expertise required to accomplish the USGS mission in natural hazards includes a wide range of disciplines that this report refers to, in aggregate, as hazard science. In October 2010, the Natural Hazards Science Strategy Planning Team (H-SSPT) was charged with developing a long-term (10-year) Science Strategy for the USGS mission in natural hazards. This report fulfills that charge, with a document hereinafter referred to as the Strategy, to provide scientific observations, analyses, and research that are critical for the Nation to become more resilient to natural hazards. Science provides the information that decisionmakers need to determine whether risk management activities are worthwhile. Moreover, as the agency with the perspective of geologic time, the USGS is uniquely positioned to extend the collective experience of society to prepare for events outside current memory. The USGS has critical statutory

  18. Natural hazards science strategy

    USGS Publications Warehouse

    Holmes, Jr., Robert R.; Jones, Lucile M.; Eidenshink, Jeffery C.; Godt, Jonathan W.; Kirby, Stephen H.; Love, Jeffrey J.; Neal, Christina A.; Plant, Nathaniel G.; Plunkett, Michael L.; Weaver, Craig S.; Wein, Anne; Perry, Suzanne C.

    2012-01-01

    The mission of the U.S. Geological Survey (USGS) in natural hazards is to develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation. The costs and consequences of natural hazards can be enormous, and each year more people and infrastructure are at risk. USGS scientific research—founded on detailed observations and improved understanding of the responsible physical processes—can help to understand and reduce natural hazard risks and to make and effectively communicate reliable statements about hazard characteristics, such as frequency, magnitude, extent, onset, consequences, and where possible, the time of future events.To accomplish its broad hazard mission, the USGS maintains an expert workforce of scientists and technicians in the earth sciences, hydrology, biology, geography, social and behavioral sciences, and other fields, and engages cooperatively with numerous agencies, research institutions, and organizations in the public and private sectors, across the Nation and around the world. The scientific expertise required to accomplish the USGS mission in natural hazards includes a wide range of disciplines that this report refers to, in aggregate, as hazard science.In October 2010, the Natural Hazards Science Strategy Planning Team (H–SSPT) was charged with developing a long-term (10-year) Science Strategy for the USGS mission in natural hazards. This report fulfills that charge, with a document hereinafter referred to as the Strategy, to provide scientific observations, analyses, and research that are critical for the Nation to become more resilient to natural hazards. Science provides the information that decisionmakers need to determine whether risk management activities are worthwhile. Moreover, as the agency with the perspective of geologic time, the USGS is uniquely positioned to extend the collective experience of society to prepare for events outside current memory. The USGS has critical statutory

  19. Design, science and naturalism

    NASA Astrophysics Data System (ADS)

    Deming, David

    2008-09-01

    The Design Argument is the proposition that the presence of order in the universe is evidence for the existence of God. The Argument dates at least to the presocratic Greek philosophers, and is largely based on analogical reasoning. Following the appearance of Aquinas' Summa Theologica in the 13th century, the Christian Church in Europe embraced a Natural Theology based on observation and reason that allowed it to dominate the entire world of knowledge. Science in turn advanced itself by demonstrating that it could be of service to theology, the recognized queen of the sciences. During the heyday of British Natural Theology in the 17th and 18th centuries, the watchmaker, shipbuilder, and architect analogies were invoked reflexively by philosophers, theologians, and scientists. The Design Argument was not systematically and analytically criticized until David Hume wrote Dialogues on Natural Religion in the 1750s. After Darwin published Origin of Species in 1859, Design withered on the vine. But in recent years, the Argument has been resurrected under the appellation "intelligent design," and been the subject of political and legal controversy in the United States. Design advocates have argued that intelligent design can be formulated as a scientific hypothesis, that new scientific discoveries validate a design inference, and that naturalism must be removed as a methodological requirement in science. If science is defined by a model of concentric epistemological zonation, design cannot be construed as a scientific hypothesis because it is inconsistent with the core aspects of scientific methodology: naturalism, uniformity, induction, and efficient causation. An analytical examination of claims by design advocates finds no evidence of any type to support either scientific or philosophical claims that design can be unambiguously inferred from nature. The apparent irreducible complexity of biological mechanisms may be explained by exaptation or scaffolding. The argument

  20. Natural light illumination system.

    PubMed

    Whang, Allen Jong-Woei; Chen, Yi-Yung; Yang, Shu-Hua; Pan, Po-Hsuan; Chou, Kao-Hsu; Lee, Yu-Chi; Lee, Zong-Yi; Chen, Chi-An; Chen, Cheng-Nan

    2010-12-10

    In recent years, green energy has undergone a lot of development and has been the subject of many applications. Many research studies have focused on illumination with sunlight as a means of saving energy and creating healthy lighting. Natural light illumination systems have collecting, transmitting, and lighting elements. Today, most daylight collectors use dynamic concentrators; these include Sun tracking systems. However, this design is too expensive to be cost effective. To create a low-cost collector that can be easily installed on a large building, we have designed a static concentrator, which is prismatic and cascadable, to collect sunlight for indoor illumination. The transmission component uses a large number of optical fibers. Because optical fibers are expensive, this means that most of the cost for the system will be related to transmission. In this paper, we also use a prismatic structure to design an optical coupler for coupling n to 1. With the n-to-1 coupler, the number of optical fibers necessary can be greatly reduced. Although this new natural light illumination system can effectively guide collected sunlight and send it to the basement or to other indoor places for healthy lighting, previously there has been no way to manage the collected sunlight when lighting was not desired. To solve this problem, we have designed an optical switch and a beam splitter to control and separate the transmitted light. When replacing traditional sources, the lighting should have similar characteristics, such as intensity distribution and geometric parameters, to those of traditional artificial sources. We have designed, simulated, and optimized an illumination lightpipe with a dot pattern to redistribute the collected sunlight from the natural light illumination system such that it equals the qualities of a traditional lighting system. We also provide an active lighting module that provides lighting from the natural light illumination system or LED auxiliary

  1. Naturally selecting solutions

    PubMed Central

    Manning, Timmy; Sleator, Roy D; Walsh, Paul

    2013-01-01

    For decades, computer scientists have looked to nature for biologically inspired solutions to computational problems; ranging from robotic control to scheduling optimization. Paradoxically, as we move deeper into the post-genomics era, the reverse is occurring, as biologists and bioinformaticians look to computational techniques, to solve a variety of biological problems. One of the most common biologically inspired techniques are genetic algorithms (GAs), which take the Darwinian concept of natural selection as the driving force behind systems for solving real world problems, including those in the bioinformatics domain. Herein, we provide an overview of genetic algorithms and survey some of the most recent applications of this approach to bioinformatics based problems. PMID:23222169

  2. Clathrate hydrates in nature.

    PubMed

    Hester, Keith C; Brewer, Peter G

    2009-01-01

    Scientific knowledge of natural clathrate hydrates has grown enormously over the past decade, with spectacular new findings of large exposures of complex hydrates on the sea floor, the development of new tools for examining the solid phase in situ, significant progress in modeling natural hydrate systems, and the discovery of exotic hydrates associated with sea floor venting of liquid CO2. Major unresolved questions remain about the role of hydrates in response to climate change today, and correlations between the hydrate reservoir of Earth and the stable isotopic evidence of massive hydrate dissociation in the geologic past. The examination of hydrates as a possible energy resource is proceeding apace for the subpermafrost accumulations in the Arctic, but serious questions remain about the viability of marine hydrates as an economic resource. New and energetic explorations by nations such as India and China are quickly uncovering large hydrate findings on their continental shelves.

  3. Natural convective mixing flows

    NASA Astrophysics Data System (ADS)

    Ramos, Eduardo; de La Cruz, Luis; del Castillo, Luis

    1998-11-01

    Natural convective mixing flows. Eduardo Ramos and Luis M. de La Cruz, National University of Mexico and Luis Del Castillo San Luis Potosi University. The possibility of mixing a fluid with a natural convective flow is analysed by solving numerically the mass, momentum and energy equations in a cubic container. Two opposite vertical walls of the container are assumed to have temperatures that oscillate as functions of time. The phase of the oscillations is chosen in such a way that alternating corrotating vortices are formed in the cavity. The mixing efficiency of this kind of flow is examined with a Lagrangian tracking technique. This work was partially financed by CONACyT-Mexico project number GE0044

  4. Mysteries of nature.

    PubMed

    Molnar, Michael

    2011-01-01

    This article examines a group photograph of the Psychiatry and Neurology section of the 66th Meeting of the Society of German Natural Scientists and Doctors in Vienna, 24-30 September 1894 which Sigmund Freud attended. The society's origins in Naturphilosophie are indicated and a number of the participants are identified on the photo. They and the events at the conference are related to Sigmund Freud's work at the time and to his gradual abandonment of anatomy and of heredity and degeneration as significant aetiological factors in the neuroses. Philosophical problems, such as how phenomena should be described and how 'nature' is conceptualized, are also considered in the light of their implications for Freud's life and thought at that period.

  5. Hybrid Natural Inflation

    NASA Astrophysics Data System (ADS)

    Ross, Graham G.; Germán, Gabriel; Vázquez, J. Alberto

    2016-05-01

    We construct two simple effective field theory versions of Hybrid Natural Inflation (HNI) that illustrate the range of its phenomenological implications. The resulting inflationary sector potential, V = Δ4(1 + acos( ϕ/f)), arises naturally, with the inflaton field a pseudo-Nambu-Goldstone boson. The end of inflation is triggered by a waterfall field and the conditions for this to happen are determined. Also of interest is the fact that the slow-roll parameter ɛ (and hence the tensor r) is a non-monotonic function of the field with a maximum where observables take universal values that determines the maximum possible tensor to scalar ratio r. In one of the models the inflationary scale can be as low as the electroweak scale. We explore in detail the associated HNI phenomenology, taking account of the constraints from Black Hole production, and perform a detailed fit to the Planck 2015 temperature and polarisation data.

  6. Notes on natural inflation

    NASA Astrophysics Data System (ADS)

    Yonekura, Kazuya

    2014-10-01

    In the so-called natural inflation, an axion-like inflaton is assumed to have a cosine-type periodic potential. This is not the case in a very simple model in which the axion-like inflaton is coupled to an SU(N) (or other) pure Yang-Mills, at least in the large N limit as pointed out by Witten. It has a multi-valued potential, which is effectively quadratic, i.e., there is only a mass term in the large N limit. Thanks to this property, chaotic inflation can be realized more naturally with the decay constant of the axion-like inflaton less than the Planck scale. We demonstrate these points explicitly by using softly broken Script N=1 Super-Yang-Mills which allows us to treat finite N. This analysis also suggests that moderately large gauge groups such as E8 are good enough with a Planck scale decay constant.

  7. Natural Products for Antithrombosis

    PubMed Central

    Chen, Cen; Zhang, Qian; Wang, Feng-Qin; Hu, Yuan-Jia; Xia, Zhi-Ning

    2015-01-01

    Thrombosis is considered to be closely related to several diseases such as atherosclerosis, ischemic heart disease and stroke, as well as rheumatoid arthritis, hyperuricemia, and various inflammatory conditions. More and more studies have been focused on understanding the mechanism of molecular and cellular basis of thrombus formation as well as preventing thrombosis for the treatment of thrombotic diseases. In reality, there is considerable interest in the role of natural products and their bioactive components in the prevention and treatment of thrombosis related disorders. This paper briefly describes the mechanisms of thrombus formation on three aspects, including coagulation system, platelet activation, and aggregation, and change of blood flow conditions. Furthermore, the natural products for antithrombosis by anticoagulation, antiplatelet aggregation, and fibrinolysis were summarized, respectively. PMID:26075003

  8. Safer Liquid Natural Gas

    NASA Technical Reports Server (NTRS)

    1976-01-01

    After the disaster of Staten Island in 1973 where 40 people were killed repairing a liquid natural gas storage tank, the New York Fire Commissioner requested NASA's help in drawing up a comprehensive plan to cover the design, construction, and operation of liquid natural gas facilities. Two programs are underway. The first transfers comprehensive risk management techniques and procedures which take the form of an instruction document that includes determining liquid-gas risks through engineering analysis and tests, controlling these risks by setting up redundant fail safe techniques, and establishing criteria calling for decisions that eliminate or accept certain risks. The second program prepares a liquid gas safety manual (the first of its kind).

  9. Natural environment analysis

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Qualitative analyses (and quantitatively to the extend possible) of the influence of terrain features on wind loading of the space shuttle while on the launch pad, or during early liftoff, are presented. Initially, the climatology and meteorology producing macroscale wind patterns and characteristics fot he Vandenburg Air Force Base (VAFB) launch site are described. Also, limited field test data are analyzed, and then the nature and characteristic of flow disturbances due to the various terrain features, both natural and man-made, are then reviewed. Following this, the magnitude of these wind loads are estimated. Finally, effects of turbulence are discussed. The study concludes that the influence of complex terrain can create significant wind loading on the vehicle. Because of the limited information, it is not possible to quantify the magnitude of these loads.

  10. Epidemics after natural disasters.

    PubMed

    Watson, John T; Gayer, Michelle; Connolly, Maire A

    2007-01-01

    The relationship between natural disasters and communicable diseases is frequently misconstrued. The risk for outbreaks is often presumed to be very high in the chaos that follows natural disasters, a fear likely derived from a perceived association between dead bodies and epidemics. However, the risk factors for outbreaks after disasters are associated primarily with population displacement. The availability of safe water and sanitation facilities, the degree of crowding, the underlying health status of the population, and the availability of healthcare services all interact within the context of the local disease ecology to influence the risk for communicable diseases and death in the affected population. We outline the risk factors for outbreaks after a disaster, review the communicable diseases likely to be important, and establish priorities to address communicable diseases in disaster settings.

  11. Why Is Nature Beneficial?: The Role of Connectedness to Nature

    ERIC Educational Resources Information Center

    Mayer, F. Stephan; Frants, Cynthia McPherson; Bruehlman-Senecal, Emma; Dolliver, Kyffin

    2009-01-01

    Three studies examine the effects of exposure to nature on positive affect and ability to reflect on a life problem. Participants spent 15 min walking in a natural setting (Studies 1, 2, & 3), an urban setting (Study 1), or watching videos of natural and urban settings (Studies 2 & 3). In all three studies, exposure to nature increased…

  12. Natural Underwater Adhesives.

    PubMed

    Stewart, Russell J; Ransom, Todd C; Hlady, Vladimir

    2011-06-01

    The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)(3) coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent

  13. Natural Materials, Systems & Extremophiles

    DTIC Science & Technology

    2012-03-06

    PORTFOLIO: The goals of this program are to: 1) study, use, mimic, or alter how biological systems accomplish a desired (from our point of view) task...and 2) enable them to task-specifically produce natural materials and systems. Both goals are to advance or create future USAF technologies...Program Constant with Additions Coming From Outside Program • Chromophores/Bioluminescence – Bio-X STT phase 1 focus. One of its discoveries are

  14. Natural family planning.

    PubMed

    Davis, M S

    1992-01-01

    Natural family planning includes the calendar (rhythm), basal body temperature, ovulation (mucus), and sympto-thermal methods. Reliability of such methods often is underestimated, but effectiveness of various methods has been reported. Correct understanding and use of proper techniques, primarily abstinence during fertile periods, is imperative for effectiveness. New methods being studied may heighten awareness of fertile times and shorten required periods of abstinence or use of back-up methods.

  15. Natural sampling strategy

    NASA Technical Reports Server (NTRS)

    Hallum, C. R.; Basu, J. P. (Principal Investigator)

    1979-01-01

    A natural stratum-based sampling scheme and the aggregation procedures for estimating wheat area, yield, and production and their associated prediction error estimates are described. The methodology utilizes LANDSAT imagery and agrophysical data to permit an improved stratification in foreign areas by ignoring political boundaries and restratifying along boundaries that are more homogeneous with respect to the distribution of agricultural density, soil characteristics, and average climatic conditions. A summary of test results is given including a discussion of the various problems encountered.

  16. Natural Underwater Adhesives

    PubMed Central

    Stewart, Russell J.; Ransom, Todd C.; Hlady, Vladimir

    2011-01-01

    The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)3 coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent

  17. Nature's Greatest Puzzles

    SciTech Connect

    Quigg, Chris; /Fermilab

    2005-02-01

    It is a pleasure to be part of the SLAC Summer Institute again, not simply because it is one of the great traditions in our field, but because this is a moment of great promise for particle physics. I look forward to exploring many opportunities with you over the course of our two weeks together. My first task in talking about Nature's Greatest Puzzles, the title of this year's Summer Institute, is to deconstruct the premise a little bit.

  18. Thermoacoustic natural gas liquefier

    SciTech Connect

    Swift, G.W.

    1997-05-01

    Cryenco and Los Alamos are collaborating to develop a natural-gas-powered natural-gas liquefier that will have no moving parts and require no electrical power. It will have useful efficiency, remarkable reliability, and low cost. The liquefaction of natural gas, which occurs at only 115 Kelvin at atmospheric pressure, has previously required rather sophisticated refrigeration machinery. The 1990 invention of the thermoacoustically driven orifice pulse-tube refrigerator (TA-DOPTR) provides cryogenic refrigeration with no moving parts for the first time. In short, this invention uses acoustic phenomena to produce refrigeration from heat. The required apparatus consists of nothing more than helium-filled heat exchangers and pipes, made of common materials, without exacting tolerances. In the Cryenco-Los Alamos collaboration, the authors are developing a version of this invention suitable for use in the natural-gas industry. The project is known as acoustic liquefier for short. The present program plans call for a two-phase development. Phase 1, with capacity of 500 gallon per day (i.e., approximately 40,000 scfd, requiring a refrigeration power of about 7 kW), is large enough to illuminate all the issues of large-scale acoustic liquefaction without undue cost, and to demonstrate the liquefaction of 60--70% of input gas, while burning 30--40%. Phase 2 will target versions of approximately 10{sup 6} scfd = 10,000 gallon per day capacity. In parallel with both, they continue fundamental research on the technology, directed toward increased efficiency, to build scientific foundations and a patent portfolio for future acoustic liquefiers.

  19. Natural language generation

    NASA Astrophysics Data System (ADS)

    Maybury, Mark T.

    The goal of natural language generation is to replicate human writers or speakers: to generate fluent, grammatical, and coherent text or speech. Produced language, using both explicit and implicit means, must clearly and effectively express some intended message. This demands the use of a lexicon and a grammar together with mechanisms which exploit semantic, discourse and pragmatic knowledge to constrain production. Furthermore, special processors may be required to guide focus, extract presuppositions, and maintain coherency. As with interpretation, generation may require knowledge of the world, including information about the discourse participants as well as knowledge of the specific domain of discourse. All of these processes and knowledge sources must cooperate to produce well-written, unambiguous language. Natural language generation has received less attention than language interpretation due to the nature of language: it is important to interpret all the ways of expressing a message but we need to generate only one. Furthermore, the generative task can often be accomplished by canned text (e.g., error messages or user instructions). The advent of more sophisticated computer systems, however, has intensified the need to express multisentential English.

  20. NATURAL RESOURCES ASSESSMENT

    SciTech Connect

    D.F. Fenster

    2000-12-11

    The purpose of this report is to summarize the scientific work that was performed to evaluate and assess the occurrence and economic potential of natural resources within the geologic setting of the Yucca Mountain area. The extent of the regional areas of investigation for each commodity differs and those areas are described in more detail in the major subsections of this report. Natural resource assessments have focused on an area defined as the ''conceptual controlled area'' because of the requirements contained in the U.S. Nuclear Regulatory Commission Regulation, 10 CFR Part 60, to define long-term boundaries for potential radionuclide releases. New requirements (proposed 10 CFR Part 63 [Dyer 1999]) have obviated the need for defining such an area. However, for the purposes of this report, the area being discussed, in most cases, is the previously defined ''conceptual controlled area'', now renamed the ''natural resources site study area'' for this report (shown on Figure 1). Resource potential can be difficult to assess because it is dependent upon many factors, including economics (demand, supply, cost), the potential discovery of new uses for resources, or the potential discovery of synthetics to replace natural resource use. The evaluations summarized are based on present-day use and economic potential of the resources. The objective of this report is to summarize the existing reports and information for the Yucca Mountain area on: (1) Metallic mineral and mined energy resources (such as gold, silver, etc., including uranium); (2) Industrial rocks and minerals (such as sand, gravel, building stone, etc.); (3) Hydrocarbons (including oil, natural gas, tar sands, oil shales, and coal); and (4) Geothermal resources. Groundwater is present at the Yucca Mountain site at depths ranging from 500 to 750 m (about 1,600 to 2,500 ft) below the ground surface. Groundwater resources are not discussed in this report, but are planned to be included in the hydrology

  1. Competing phytoplankton undermines allelopathy of a bloom-forming dinoflagellate.

    PubMed

    Prince, Emily K; Myers, Tracey L; Naar, Jerome; Kubanek, Julia

    2008-12-07

    Biotic interactions in the plankton can be both complex and dynamic. Competition among phytoplankton is often chemically mediated, but no studies have considered whether allelopathic compounds are modified by biotic interactions. Here, we show that compounds exuded during Karenia brevis blooms were allelopathic to the cosmopolitan diatom Skeletonema costatum, but that bloom allelopathy varied dramatically among collections and years. We investigated several possible causes of this variability and found that neither bloom density nor concentrations of water-borne brevetoxins correlated with allelopathic potency. However, when we directly tested whether the presence of competing phytoplankton influenced bloom allelopathy, we found that S. costatum reduced the growth-inhibiting effects of bloom exudates, suggesting that S. costatum has a mechanism for undermining K. brevis allelopathy. Additional laboratory experiments indicated that inducible changes to K. brevis allelopathy were restricted to two diatoms among five sensitive phytoplankton species, whereas five other species were constitutively resistant to K. brevis allelopathy. Our results suggest that competitors differ in their responses to phytoplankton allelopathy, with S. costatum exhibiting a previously undescribed method of resistance that may influence community structure and alter bloom dynamics.

  2. Why Nature Chose Selenium.

    PubMed

    Reich, Hans J; Hondal, Robert J

    2016-04-15

    The authors were asked by the Editors of ACS Chemical Biology to write an article titled "Why Nature Chose Selenium" for the occasion of the upcoming bicentennial of the discovery of selenium by the Swedish chemist Jöns Jacob Berzelius in 1817 and styled after the famous work of Frank Westheimer on the biological chemistry of phosphate [Westheimer, F. H. (1987) Why Nature Chose Phosphates, Science 235, 1173-1178]. This work gives a history of the important discoveries of the biological processes that selenium participates in, and a point-by-point comparison of the chemistry of selenium with the atom it replaces in biology, sulfur. This analysis shows that redox chemistry is the largest chemical difference between the two chalcogens. This difference is very large for both one-electron and two-electron redox reactions. Much of this difference is due to the inability of selenium to form π bonds of all types. The outer valence electrons of selenium are also more loosely held than those of sulfur. As a result, selenium is a better nucleophile and will react with reactive oxygen species faster than sulfur, but the resulting lack of π-bond character in the Se-O bond means that the Se-oxide can be much more readily reduced in comparison to S-oxides. The combination of these properties means that replacement of sulfur with selenium in nature results in a selenium-containing biomolecule that resists permanent oxidation. Multiple examples of this gain of function behavior from the literature are discussed.

  3. Nature, Nurture and Epigenetics

    PubMed Central

    Crews, David; Gillette, Ross; Miller-Crews, Isaac; Gore, Andrea C.; Skinner, Michael K.

    2015-01-01

    Real life by definition combines heritability (e.g., the legacy of exposures) and experience (e.g. stress during sensitive or ‘critical’ periods), but how to study or even model this interaction has proven difficult. The hoary concept of evaluating traits according to nature vs. nurture continues to persist despite repeated demonstrations that it retards, rather than advances, our understanding of biological processes. Behavioral genetics has proven the obvious, that genes influences behavior and, vice versa, that behavior influences genes. The concept of Genes X Environment (G X E) and its modern variants was viewed as an improvement on nature-nurture but has proven that, except in rare instances, it is not possible to fractionate phenotypes into these constituent elements. The entanglement inherent in terms such as nature-nurture or GXE is a Gordian knot that cannot be dissected or even split. Given that the world today is not what it was less than a century ago, yet the arbitrator (differential survival and reproduction) has stayed constant, de novo principles and practices are needed to better predict what the future holds. Put simply, the transformation that is now occurring within and between individuals as a product of global endocrine disruption is quite independent of what has been regarded as evolution by selection. This new perspective should focus on how epigenetic modifications might revise approaches to understand how the phenotype and, in particular its components, is shaped. In this review we summarize the literature in this developing area, focusing on our research on the fungicide vinclozolin. PMID:25102229

  4. Nature Inspired Surface Coatings

    NASA Astrophysics Data System (ADS)

    Rubner, Michael

    2011-04-01

    Materials Scientists more and more are looking to nature for clues on how to create highly functional surface coatings with exceptional properties. The fog harvesting capabilities of the Namib Desert beetle, the beautiful iridescent colors of the hummingbird, and the super water repellant abilities of the Lotus leaf are but a few examples of the amazing properties developed over many years in the natural world. Nature also makes extensive use of the pH-dependent behavior of weak functional groups such as carboxylic acid and amine functional groups. This presentation will explore synthetic mimics to the nano- and microstructures responsible for these fascinating properties. For example, we have demonstrated a pH-induced porosity transition that can be used to create porous films with pore sizes that are tunable from the nanometer scale to the multiple micron scale. The pores of these films, either nano- or micropores, can be reversibly opened and closed by changes in solution pH. The ability to engineer pH-gated porosity transitions in heterostructured thin films has led to the demonstration of broadband anti-reflection coatings that mimic the anti-reflection properties of the moth eye and pH-tunable Bragg reflectors with a structure and function similar to that found in hummingbird wings and the Longhorn beetle. In addition, the highly textured honeycomb-like surfaces created by the formation of micron-scale pores are ideally suited for the creation of superhydrophobic surfaces that mimic the behavior of the self-cleaning lotus leaf. The development of synthetic "backbacks" on immune system cells that may one day ferry drugs to disease sites will also be discussed.

  5. Nature, nurture and epigenetics.

    PubMed

    Crews, David; Gillette, Ross; Miller-Crews, Isaac; Gore, Andrea C; Skinner, Michael K

    2014-12-01

    Real life by definition combines heritability (e.g., the legacy of exposures) and experience (e.g. stress during sensitive or 'critical' periods), but how to study or even model this interaction has proven difficult. The hoary concept of evaluating traits according to nature versus nurture continues to persist despite repeated demonstrations that it retards, rather than advances, our understanding of biological processes. Behavioral genetics has proven the obvious, that genes influence behavior and, vice versa, that behavior influences genes. The concept of Genes X Environment (G X E) and its modern variants was viewed as an improvement on nature-nurture but has proven that, except in rare instances, it is not possible to fractionate phenotypes into these constituent elements. The entanglement inherent in terms such as nature-nurture or G X E is a Gordian knot that cannot be dissected or even split. Given that the world today is not what it was less than a century ago, yet the arbitrator (differential survival and reproduction) has stayed constant, de novo principles and practices are needed to better predict what the future holds. Put simply, the transformation that is now occurring within and between individuals as a product of global endocrine disruption is quite independent of what has been regarded as evolution by selection. This new perspective should focus on how epigenetic modifications might revise approaches to understand how the phenotype and, in particular its components, is shaped. In this review we summarize the literature in this developing area, focusing on our research on the fungicide vinclozolin.

  6. "Naturally occurring asbestos

    NASA Astrophysics Data System (ADS)

    Cagnard, F.; Lahondère, D.; Blein, O.; Lahfid, A.; Wille, G.

    2012-04-01

    The term asbestos refers to six silicate minerals from amphibole and serpentine groups. By definition, it consists in bundles of thin and flexible long fibers, with high-tensile strength, and chemical and heat resistance. In contrast to asbestos found within commercial products and mining, the specific term ''naturally occurring asbestos'' (NOA) refers to asbestiform minerals occurring within rocks or soils that can be released by human activities or weathering processes. The fact that the exposure to asbestos is related to lung pathologies is now widely demonstrated (e.g. asbestosis, mesothelioma and lung cancer). However, if health risks associated with exposure to NOA exist, they are not yet well documented. The crystallization of natural asbestos occurs in specific Mg-rich lithologies associated with peculiar structural and metamorphic conditions. By recognizing and combining such specific geologic criteria, the presence or the absence of asbestos in bedrock terrains can be reasonably predicted and maps of NOA hazard can be drawn. We present here new results of geological mapping and petrological study concerning the evaluation of the NOA hazard in the Alps and Corsica, in France. The three folds approach consists in (1) a determination of lithologies with potential NOA from a bibliographic compilation and extraction of target zones from a geological geodatabase (2) a geological mapping of the target zones followed by a petrological characterization of sampled asbestiform minerals in the laboratory (optical microscopy, TEM, SEM, and Raman spectroscopy technics), and (3) the drawing of the final map of NOA hazard, at regional-scale. Occurrence criteria can be retained as follows: 1. NOA are abundant in the internal zones of the Alps and Corsica, especially within ophiolitic complexes. Natural asbestos are mostly concentrated within ultramafic rocks but can also occur within basic lithologies such as Mg-metagabbros, metabasalts and meta-pillow-lavas, 2. Asbestos

  7. Marine natural products.

    PubMed

    Blunt, John W; Copp, Brent R; Keyzers, Robert A; Munro, Murray H G; Prinsep, Michèle R

    2015-02-01

    This review covers the literature published in 2013 for marine natural products (MNPs), with 982 citations (644 for the period January to December 2013) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1163 for 2013), together with the relevant biological activities, source organisms and country of origin. Reviews, biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.

  8. Marine natural products.

    PubMed

    Blunt, John W; Copp, Brent R; Keyzers, Robert A; Munro, Murray H G; Prinsep, Michèle R

    2014-01-17

    This review covers the literature published in 2012 for marine natural products, with 1035 citations (673 for the period January to December 2012) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1241 for 2012), together with the relevant biological activities, source organisms and country of origin. Biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.

  9. Natural Killer Cell Memory.

    PubMed

    O'Sullivan, Timothy E; Sun, Joseph C; Lanier, Lewis L

    2015-10-20

    Natural killer (NK) cells have historically been considered short-lived cytolytic cells that can rapidly respond against pathogens and tumors in an antigen-independent manner and then undergo cell death. Recently, however, NK cells have been shown to possess traits of adaptive immunity and can acquire immunological memory in a manner similar to that of T and B cells. In this review, we discuss evidence of NK cell memory and the mechanisms involved in the generation and survival of these innate lymphocytes.

  10. Florida Red Tide Perception: Residents versus Tourists

    PubMed Central

    Nierenberg, Kate; Byrne, Margaret; Fleming, Lora E.; Stephan, Wendy; Reich, Andrew; Backer, Lorraine C.; Tanga, Elvira; Dalpra, Dana R.; Kirkpatrick, Barbara

    2010-01-01

    The west coast of Florida has annual blooms of the toxin-producing dinoflagellate, Karenia brevis with Sarasota, FL considered the epicenter for these blooms. Numerous outreach materials, including Frequently Asked Question (FAQ) cards, exhibits for local museums and aquaria, public beach signs, and numerous websites have been developed to disseminate information to the public about this natural hazard. In addition, during intense onshore blooms, a great deal of media attention, primarily via newspaper (print and web) and television, is focused on red tide. However to date, the only measure of effectiveness of these outreach methods has been counts of the number of people exposed to the information, e.g., visits to a website or number of FAQ cards distributed. No formal assessment has been conducted to determine if these materials meet their goal of informing the public about Florida red tide. Also, although local residents have the opinion that they are very knowledgeable about Florida red tide, this has not been verified empirically. This study addressed these issues by creating and administering an evaluation tool for the assessment of public knowledge about Florida red tide. A focus group of Florida red tide outreach developers assisted in the creation of the evaluation tool. The location of the evaluation was the west coast of Florida, in Sarasota County. The objective was to assess the knowledge of the general public about Florida red tide. This assessment identified gaps in public knowledge regarding Florida red tides and also identified what information sources people want to use to obtain information on Florida red tide. The results from this study can be used to develop more effective outreach materials on Florida red tide. PMID:20824108

  11. Human responses to Florida red tides: policy awareness and adherence to local fertilizer ordinances.

    PubMed

    Kirkpatrick, Barbara; Kohler, Kate; Byrne, Margaret; Fleming, Lora E; Scheller, Karen; Reich, Andrew; Hitchcock, Gary; Kirkpatrick, Gary; Ullmann, Steven; Hoagland, Porter

    2014-09-15

    To mitigate the damages of natural hazards, policy responses can be beneficial only if they are effective. Using a self-administered survey approach, this paper focuses on the adherence to local fertilizer ordinances (i.e., county or municipal rules regulating the application of fertilizer to private lawns or facilities such as golf courses) implemented in jurisdictions along the Southwest Florida coast in response to hazardous blooms of Florida red tides (Karenia brevis). These ordinances play a role in the context of evolving programs of water pollution control at federal, state, water basin, and local levels. With respect to policy effectiveness, while the strength of physical linkages is of critical importance, the extent to which humans affected are aware of and adhere to the relevant rules, is equally critical. We sought to understand the public's depth of understanding about the rationales for local fertilizer ordinances. Respondents in Sarasota, Florida, were asked about their fertilizer practices in an area that has experienced several major blooms of Florida red tides over the past two decades. A highly educated, older population of 305 residents and "snowbirds" reported relatively little knowledge about a local fertilizer ordinance, its purpose, or whether it would change the frequency, size, or duration of red tides. This finding held true even among subpopulations that were expected to have more interest in or to be more knowledgeable about harmful algal blooms. In the face of uncertain science and environmental outcomes, and with individual motivations at odds with evolving public policies, the effectiveness of local community efforts to decrease the impacts of red tides may be compromised. Targeted social-science research on human perceptions about the risks of Florida red tides and education about the rationales for potential policy responses are warranted.

  12. Florida Red Tide Perception: Residents versus Tourists.

    PubMed

    Nierenberg, Kate; Byrne, Margaret; Fleming, Lora E; Stephan, Wendy; Reich, Andrew; Backer, Lorraine C; Tanga, Elvira; Dalpra, Dana R; Kirkpatrick, Barbara

    2010-09-01

    The west coast of Florida has annual blooms of the toxin-producing dinoflagellate, Karenia brevis with Sarasota, FL considered the epicenter for these blooms. Numerous outreach materials, including Frequently Asked Question (FAQ) cards, exhibits for local museums and aquaria, public beach signs, and numerous websites have been developed to disseminate information to the public about this natural hazard. In addition, during intense onshore blooms, a great deal of media attention, primarily via newspaper (print and web) and television, is focused on red tide. However to date, the only measure of effectiveness of these outreach methods has been counts of the number of people exposed to the information, e.g., visits to a website or number of FAQ cards distributed. No formal assessment has been conducted to determine if these materials meet their goal of informing the public about Florida red tide. Also, although local residents have the opinion that they are very knowledgeable about Florida red tide, this has not been verified empirically. This study addressed these issues by creating and administering an evaluation tool for the assessment of public knowledge about Florida red tide. A focus group of Florida red tide outreach developers assisted in the creation of the evaluation tool. The location of the evaluation was the west coast of Florida, in Sarasota County. The objective was to assess the knowledge of the general public about Florida red tide. This assessment identified gaps in public knowledge regarding Florida red tides and also identified what information sources people want to use to obtain information on Florida red tide. The results from this study can be used to develop more effective outreach materials on Florida red tide.

  13. Personal exposure to aerosolized red tide toxins (brevetoxins).

    PubMed

    Cheng, Yung Sung; Zhou, Yue; Naar, Jerome; Irvin, C Mitch; Su, Wei-Chung; Fleming, Lora E; Kirkpatrick, Barbara; Pierce, Richard H; Backer, Lorraine C; Baden, Daniel G

    2010-06-01

    Florida red tides occur annually in the Gulf of Mexico from blooms of the marine dinoflagellate, Karenia brevis, which produces highly potent natural polyether toxins, brevetoxins. Several epidemiologic studies have demonstrated that human exposure to red tide aerosol could result in increased respiratory symptoms. Environmental monitoring of aerosolized brevetoxins was performed using a high-volume sampler taken hourly at fixed locations on Siesta Beach, Florida. Personal exposure was monitored using personal air samplers and taking nasal swab samples from the subjects who were instructed to spend 1 hr on Sarasota Beach during two sampling periods of an active Florida red tide event in March 2005, and in May 2008 when there was no red tide. Results showed that the aerosolized brevetoxins from the personal sampler were in modest agreement with the environmental concentration taken from a high-volume sampler. Analysis of nasal swab samples for brevetoxins demonstrated 68% positive samples in the March 2005 sampling period when air concentrations of brevetoxins were between 50 to 120 ng/m(3) measured with the high-volume sampler. No swab samples showed detectable levels of brevetoxins in the May 2008 study, when all personal samples were below the limit of detection. However, there were no statistical correlations between the amounts of brevetoxins detected in the swab samples with either the environmental or personal concentration. Results showed that the personal sample might provide an estimate of individual exposure level. Nasal swab samples showed that brevetoxins indeed were inhaled and deposited in the nasal passage during the March 2005 red tide event.

  14. Naturally Occurring Food Toxins

    PubMed Central

    Dolan, Laurie C.; Matulka, Ray A.; Burdock, George A.

    2010-01-01

    Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration (FDA) and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions. Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins. Regardless of measures taken by regulators and food producers to protect consumers from natural food toxins, consumption of small levels of these materials is unavoidable. Although the risk for toxicity due to consumption of food toxins is fairly low, there is always the possibility of toxicity due to contamination, overconsumption, allergy or an unpredictable idiosyncratic response. The purpose of this review is to provide a toxicological and regulatory overview of some of the toxins present in some commonly consumed foods, and where possible, discuss the steps that have been taken to reduce consumer exposure, many of which are possible because of the unique process of food regulation in the United States. PMID:22069686

  15. Natural medicaments in dentistry

    PubMed Central

    Sinha, Dakshita J.; Sinha, Ashish A.

    2014-01-01

    The major objective in root canal treatment is to disinfect the entire root canal system. Cleaning, shaping, and use of antimicrobial medicaments are effective in reducing the bacterial load to some extent, but some bacteria do remain behind and multiply, causing reinfection. Taking into consideration the ineffectiveness, potential side-effects and safety concerns of synthetic drugs, the herbal alternatives for endodontic usage might prove to be advantageous. Over the past decade, interest in drugs derived from medicinal plants has markedly increased. Phytomedicine has been used in dentistry as anti-inflammatory, antibiotic, analgesic, sedative and also as endodontic irrigant. Herbal preparations can be derived from the root, leaves, seeds, stem, and flowers. The PubMed database search revealed that the reference list for natural medicaments featured 1480 articles and in dentistry 173 articles. A forward search was undertaken on the selected articles and author names. This review focuses on various natural drugs and products as well as their therapeutic applications when used as phytomedicine in dentistry. PMID:25558153

  16. Natural medicaments in dentistry.

    PubMed

    Sinha, Dakshita J; Sinha, Ashish A

    2014-04-01

    The major objective in root canal treatment is to disinfect the entire root canal system. Cleaning, shaping, and use of antimicrobial medicaments are effective in reducing the bacterial load to some extent, but some bacteria do remain behind and multiply, causing reinfection. Taking into consideration the ineffectiveness, potential side-effects and safety concerns of synthetic drugs, the herbal alternatives for endodontic usage might prove to be advantageous. Over the past decade, interest in drugs derived from medicinal plants has markedly increased. Phytomedicine has been used in dentistry as anti-inflammatory, antibiotic, analgesic, sedative and also as endodontic irrigant. Herbal preparations can be derived from the root, leaves, seeds, stem, and flowers. The PubMed database search revealed that the reference list for natural medicaments featured 1480 articles and in dentistry 173 articles. A forward search was undertaken on the selected articles and author names. This review focuses on various natural drugs and products as well as their therapeutic applications when used as phytomedicine in dentistry.

  17. Thermoacoustic natural gas liquefier

    SciTech Connect

    Swift, G.W.

    1995-06-01

    In collaboration with Cryenco Inc. and NIST-Boulder, we intend to develop a natural gas-powered natural-gas liquefier which has absolutely no moving parts and requires no electrical power. It will have high efficiency, remarkable reliability, and low cost. Progress on the liquefier to be constructed at Cryenco continues satisfactorily. The thermoacoustic driver is still ahead of the pulse tube refrigerator, because of NIST`s schedule. We completed the thermoacoustics design in the fall of 1994, with Los Alamos providing physics input and checks of all aspects, and Cryenco providing engineering to ASME code, drafting, etc. Completion of this design represents a significant amount of work, especially in view of the many unexpected problems encountered. Meanwhile, Cryenco and NIST have almost completed the design of the pulse tube refrigerator. At Los Alamos, we have assembled a half-size scale model of the thermoacoustic portion of the 500 gal/day TANGL. This scale model will enable easy experimentation in harmonic suppression techniques, new stack geometries, new heat-exchanger geometries, resonator coiling, and other areas. As of March 1995, the scale model is complete and we are performing routine debugging tests and modifications.

  18. Natural gas monthly, April 1999

    SciTech Connect

    1999-05-06

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. There are two feature articles in this issue: Natural gas 1998: Issues and trends, Executive summary; and Special report: Natural gas 1998: A preliminary summary. 6 figs., 28 tabs.

  19. Natural convection: Fundamentals and applications

    NASA Astrophysics Data System (ADS)

    Kakac, S.; Aung, W.; Viskanta, R.

    Among the topics discussed are: stability solutions for laminar external boundary region flows; natural convection in plane layers and cavities with volumetric energy sources; and turbulence modelling equations. Consideration is also given to: natural convection in enclosures containing tube bundles; natural limiting behaviors in porous media cavity flows; numerical solutions in laminar and turbulent natural convection; and heat transfer in the critical region of binary mixtures. Additional topics discussed include: natural convective cooling of electronic equipment; natural convection suppression in solar collectors; and laser induced buoyancy and forced convection in vertical tubes.

  20. [Natural philosophy in medieval medicine].

    PubMed

    Riha, Ortrun

    2007-01-01

    Medieval medicine is not much interested in natural philosophy. Nevertheless, it is based upon clear methodological and epistemological principles, where the word 'nature' is used in several ways. The natural 'virtues' of things--including magical ones--are most important for therapy. Human health is influenced by stars (planets, zodiac) and seasons, and the physician has to take into account such cosmic effects. The chances of healing depend on the patients' 'nature' in relation to the power of illness. A strong nature makes medicine superfluous, an overwhelming disease cannot be beaten. Thus, medicine is limited to 'neutral' situations when supporting the patient makes his 'nature' win.

  1. Natural Radioactivity in Bananas

    NASA Astrophysics Data System (ADS)

    Zagatto, V. A. B.; Medina, N. H.; Okuno, E.; Umisedo, N. K.

    2008-08-01

    The content of 40K natural radionuclide in bananas (Musa sapientum) from the Vale do Ribeira region, São Paulo, Brazil, has been measured. We have collected several samples of bananas prata and nanica, its peels, leaves, and also different soils where the banana tree was planted, such as soil with a standard amount of fertilizer, the fertilizer itself and also soil without fertilizer for comparison. We have used the gamma-ray spectroscopy technique with a NaI(T1) crystal inside a 12 cm thick lead shield to detect the gamma-radiation. The results indicate that only part of the available potassium is absorbed by the plant, which is mainly concentrated in the banana peel.

  2. Natural dispersion revisited.

    PubMed

    Johansen, Øistein; Reed, Mark; Bodsberg, Nils Rune

    2015-04-15

    This paper presents a new semi-empirical model for oil droplet size distributions generated by single breaking wave events. Empirical data was obtained from laboratory experiments with different crude oils at different stages of weathering. The paper starts with a review of the most commonly used model for natural dispersion, which is followed by a presentation of the laboratory study on oil droplet size distributions formed by breaking waves conducted by SINTEF on behalf of the NOAA/UNH Coastal Response Research Center. The next section presents the theoretical and empirical foundation for the new model. The model is based on dimensional analysis and contains two non-dimensional groups; the Weber and Reynolds number. The model was validated with data from a full scale experimental oil spill conducted in the Haltenbanken area offshore Norway in July 1982, as described in the last section of the paper.

  3. Natural Air Purifier

    NASA Technical Reports Server (NTRS)

    1993-01-01

    NASA environmental research has led to a plant-based air filtering system. Dr. B.C. Wolverton, a former NASA engineer who developed a biological filtering system for space life support, served as a consultant to Terra Firma Environmental. The company is marketing the BioFilter, a natural air purifier that combines activated carbon and other filter media with living plants and microorganisms. The filter material traps and holds indoor pollutants; plant roots and microorganisms then convert the pollutants into food for the plant. Most non-flowering house plants will work. After pollutants have been removed, the cleansed air is returned to the room through slits in the planter. Terra Firma is currently developing a filter that will also disinfect the air.

  4. Natural Product Molecular Fossils.

    PubMed

    Falk, Heinz; Wolkenstein, Klaus

    2017-01-01

    The natural products synthesized by organisms that were living a long time ago gave rise to their molecular fossils. These can consist of either the original unchanged compounds or they may undergo peripheral transformations in which their skeletons remain intact. In cases when molecular fossils can be traced to their organismic source, they are termed "geological biomarkers".This contribution describes apolar and polar molecular fossils and, in particular biomarkers, along the lines usually followed in organic chemistry textbooks, and points to their bioprecursors when available. Thus, the apolar compounds are divided in linear and branched alkanes followed by alicyclic compounds and aromatic and heterocyclic molecules, and, in particular, the geoporphyrins. The polar molecular fossils contain as functional groups or constituent units ethers, alcohols, phenols, carbonyl groups, flavonoids, quinones, and acids, or are polymers like kerogen, amber, melanin, proteins, or nucleic acids. The final sections discuss the methodology used and the fundamental processes encountered by the biomolecules described, including diagenesis, catagenesis, and metagenesis.

  5. Nature . . . an environmental yardstick

    USGS Publications Warehouse

    Pecora, William T.

    1976-01-01

    To one who has spent his professional career in geologic science, conservation always has had special meaning. In the measurements so necessary to his work the geologist develops an integrity in the use of numbers and in the qualifications attending the validity of numbers. Scientific analysis of geologic events and sequence develops a keen sense of what is coincidental, correlative, and consequential. The geologist applies his science in evaluating hazards to man as natural catastrophes and/or benefits to man such as earth materials that form the resource base of his society. But more than these the geologist has acquired a deep appreciation for the planet as a whole, its inner structure, its landscape, and the living things that abound.

  6. Liquefied Natural Gas Transfer

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Chicago Bridge & Iron Company's tanks and associated piping are parts of system for transferring liquefied natural gas from ship to shore and storing it. LNG is a "cryogenic" fluid meaning that it must be contained and transferred at very low temperatures, about 260 degrees below Fahrenheit. Before the LNG can be pumped from the ship to the storage tanks, the two foot diameter transfer pipes must be cooled in order to avoid difficulties associated with sharp differences of temperature between the supercold fluid and relatively warm pipes. Cooldown is accomplished by sending small steady flow of the cryogenic substance through the pipeline; the rate of flow must be precisely controlled or the transfer line will be subjected to undesirable thermal stress.

  7. Natural Radioactivity in Bananas

    SciTech Connect

    Zagatto, V. A. B.; Medina, N. H.; Okuno, E.; Umisedo, N. K.

    2008-08-07

    The content of {sup 40}K natural radionuclide in bananas (Musa sapientum) from the Vale do Ribeira region, Sao Paulo, Brazil, has been measured. We have collected several samples of bananas prata and nanica, its peels, leaves, and also different soils where the banana tree was planted, such as soil with a standard amount of fertilizer, the fertilizer itself and also soil without fertilizer for comparison. We have used the gamma-ray spectroscopy technique with a NaI(T1) crystal inside a 12 cm thick lead shield to detect the gamma-radiation. The results indicate that only part of the available potassium is absorbed by the plant, which is mainly concentrated in the banana peel.

  8. Natural killer cell deficiency.

    PubMed

    Orange, Jordan S

    2013-09-01

    Natural killer (NK) cells are part of the innate immune defense against infection and cancer and are especially useful in combating certain viral pathogens. The utility of NK cells in human health has been underscored by a growing number of persons who are deficient in NK cells and/or their functions. This can be in the context of a broader genetically defined congenital immunodeficiency, of which there are more than 40 presently known to impair NK cells. However, the abnormality of NK cells in certain cases represents the majority immunologic defect. In aggregate, these conditions are termed NK cell deficiency. Recent advances have added clarity to this diagnosis and identified defects in 3 genes that can cause NK cell deficiency, as well as some of the underlying biology. Appropriate consideration of these diagnoses and patients raises the potential for rational therapeutic options and further innovation.

  9. Which naturalism for bioethics? A defense of moderate (pragmatic) naturalism.

    PubMed

    Racine, Eric

    2008-02-01

    There is a growing interest in various forms of naturalism in bioethics, but there is a clear need for further clarification. In an effort to address this situation, I present three epistemological stances: anti-naturalism, strong naturalism, and moderate pragmatic naturalism. I argue that the dominant paradigm within philosophical ethics has been a form of anti-naturalism mainly supported by a strong 'is' and 'ought' distinction. This fundamental epistemological commitment has contributed to the estrangement of academic philosophical ethics from major social problems and explains partially why, in the early 1980s, 'medicine saved the life of ethics'. Rejection of anti-naturalism, however, is often associated with strong forms of naturalism that commit the naturalistic fallacy and threaten to reduce the normative dimensions of ethics to biological imperatives. This move is rightly dismissed as a pitfall since ethics is, in part, a struggle against the course of nature. Rejection of naturalism has drawbacks, however, such as deterring bioethicists from acknowledging the implicit naturalistic epistemological commitments of bioethics. I argue that a moderate pragmatic form of naturalism represents an epistemological position that best embraces the tension of anti-naturalism and strong naturalism: bioethics is neither disconnected from empirical knowledge nor subjugated to it. The discussion is based upon historical writings in philosophy and bioethics.

  10. Morphological and molecular characterization of Ptychodiscus noctiluca revealed the polyphyletic nature of the order Ptychodiscales (Dinophyceae).

    PubMed

    Gómez, Fernando; Qiu, Dajun; Dodge, John D; Lopes, Rubens M; Lin, Senjie

    2016-10-01

    The planktonic dinoflagellate Ptychodiscus noctiluca combined distinctive morphological features such as a disk-shaped anteroposteriorly compressed cell body and an apical carina, together with a flexible and tough cell covering, suggesting intermediate characteristics between thecate and naked dinoflagellates. Ptychodiscus noctiluca was examined by light, epifluorescence, and scanning electron microscopy from specimens collected in the Mediterranean Sea and the North and South Atlantic Ocean. Ptychodiscus noctiluca showed a straight apical groove that bisected the carina, a cell covering with a polygonal surface reticulum, nucleus without capsule, sulcal intrusion in the episome, sulcal ventral flange, and yellowish-green chloroplasts that are shared characters with Brachidinium/Karenia. The cell division was the typical binary fission of gymnodinioid dinoflagellates, although exceptionally in an oblique transversal axis. We examined the intraspecific variability during incubation experiments. In the fattened cells, termed as Ptychodiscus carinatus, chloroplasts transformed into dark granules, and the cell acquired the swollen and smaller stage, termed as P. inflatus. Ptychodiscus carinatus, P. inflatus, and Diplocystis antarctica are synonyms of P. noctiluca. Molecular phylogeny based on the SSU rDNA sequence revealed that Ptychodiscus branched within the short-branching dinokaryotic dinoflagellates as an independent lineage with affinity to Brachidinium/Karenia and Karlodinium/Takayama in a generally poorly resolved clade. Our results indicated that the order Ptychodiscales, established for unarmored dinoflagellates with a strongly developed pellicle, has artificially grouped thecate dinoflagellates (Kolkwitziella, Herdmania), naked dinoflagellates with thick cell covering (Balechina, Cucumeridinium) and other insufficiently known unarmored genera with typical cell coverings (Brachidinium, Ceratoperidinium).

  11. Pest management with natural products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 2012 Philadelphia ACS Symposium on Natural Products for Pest Management introduced recent discoveries and applications of natural products from insect, terrestrial plant, microbial, and synthetic sources for the management of insects, weeds, plant pathogenic microbes, and nematodes. The symposiu...

  12. Natural Gas Exports from Iran

    EIA Publications

    2012-01-01

    This assessment of the natural gas sector in Iran, with a focus on Iran’s natural gas exports, was prepared pursuant to section 505 (a) of the Iran Threat Reduction and Syria Human Rights Act of 2012 (Public Law No: 112-158). As requested, it includes: (1) an assessment of exports of natural gas from Iran; (2) an identification of the countries that purchase the most natural gas from Iran; (3) an assessment of alternative supplies of natural gas available to those countries; (4) an assessment of the impact a reduction in exports of natural gas from Iran would have on global natural gas supplies and the price of natural gas, especially in countries identified under number (2); and (5) such other information as the Administrator considers appropriate.

  13. Natural gas monthly, May 1999

    SciTech Connect

    1999-05-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time the NGM features articles designed to assist readers in using and interpreting natural gas information. 6 figs., 27 tabs.

  14. Natural gas monthly, July 1998

    SciTech Connect

    1998-07-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. 6 figs., 25 tabs.

  15. Natural gas monthly, July 1994

    SciTech Connect

    Not Available

    1994-07-20

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  16. Natural gas monthly, June 1993

    SciTech Connect

    Not Available

    1993-06-22

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  17. Natural gas monthly, November 1993

    SciTech Connect

    Not Available

    1993-11-29

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground state data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  18. Natural gas monthly: December 1993

    SciTech Connect

    Not Available

    1993-12-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. Articles are included which are designed to assist readers in using and interpreting natural gas information.

  19. Natural gas monthly, April 1995

    SciTech Connect

    1995-04-27

    The Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. 6 figs., 31 tabs.

  20. Natural gas monthly, September 1995

    SciTech Connect

    1995-09-27

    The (NGM) Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  1. Natural gas monthly, July 1993

    SciTech Connect

    Not Available

    1993-07-27

    The Natural Gas Monthly NGM highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  2. Natural gas monthly, August 1994

    SciTech Connect

    Not Available

    1994-08-24

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  3. Natural gas monthly, June 1999

    SciTech Connect

    1999-06-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. 6 figs., 25 tabs.

  4. WRF nature run

    NASA Astrophysics Data System (ADS)

    Michalakes, J.; Hacker, J.; Loft, R.; McCracken, M. O.; Snavely, A.; Wright, N. J.; Spelce, T.; Gorda, B.; Walkup, R.

    2008-07-01

    The Weather Research and Forecast (WRF) model is a model of the atmosphere for mesoscale research and operational numerical weather prediction (NWP). A petascale problem for WRF is a nature run that provides very high-resolution 'truth' against which more coarse simulations or perturbation runs may be com-pared for purposes of studying predictability, stochastic parameterization, and fundamental dynamics. We carried out a nature run involving an idealized high resolution rotating fluid on the hemisphere, at a size and resolution never before attempted, and used it to investigate scales that span the k-3 to k-5/3 kinetic energy spectral transition, via simulations. We used up to 15,360 processors of the New York Blue IBM BG/L machine at Stony Brook Uni-versity and Brookhaven National Laboratory. The grid we employed has 4486 by 4486 horizontal grid points and 101 vertical levels (2 billion cells) at 5km resolution; this is 32 times larger than the previously largest 63 million cell 2.5km resolution WRF CONUS benchmark [10]). To solve a problem of this size, we worked through issues of parallel I/O and scalability and employed more processors than have ever been used in a WRF run. We achieved a sustained 3.4 Tflop/s on the New York Blue sys-tem, inputting and then generating an enormous amount of data to produce a scientifically meaningful result. More than 200 GB of data was input to initialize the run, which then generated output datasets of 40 GB each simulated hour. The cost of output was considered a key component of our investigation. Then we ran the same problem on more than 12K processors of the XT4 system at NERSC and achieved 8.8 Tflop/s. Our primary result however is not just scalability and a high Tflop/s number, but capture of atmosphere features never before represented by simulation, and taking an important step towards understanding weather predict-ability at high resolution.

  5. Children's Moral Relationships with Nature.

    ERIC Educational Resources Information Center

    Kahn, Peter H., Jr.; McCoy, Ann

    Two studies of the development of children's moral relationships with nature addressed such questions as: (1) What does it mean to say that we have an obligation not to harm the natural environment? (2) Does the natural environment feel pain? (3) Does it have rights? or (4) Is moral obligation an inappropriate construct by which to understand the…

  6. Nature and Nationhood: Danish Perspectives

    ERIC Educational Resources Information Center

    Schnack, Karsten

    2009-01-01

    In this paper, I shall discuss Danish perspectives on nature, showing the interdependence of conceptions of "nature" and "nationhood" in the formations of a particular cultural community. Nature, thus construed, is never innocent of culture and cannot therefore simply be "restored" to some pristine, pre-lapsarian…

  7. Natural gas monthly, February 1999

    SciTech Connect

    1999-02-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. 6 figs., 28 tabs.

  8. Natural gas monthly, November 1998

    SciTech Connect

    1998-11-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. 6 figs., 27 tabs.

  9. Natural gas monthly, January 1999

    SciTech Connect

    1999-02-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. 6 figs., 28 tabs.

  10. Natural gas monthly, December 1998

    SciTech Connect

    1998-12-01

    The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. 6 figs., 28 tabs.

  11. Percents Are Not Natural Numbers

    ERIC Educational Resources Information Center

    Jacobs, Jennifer A.

    2013-01-01

    Adults are prone to treating percents, one representational format of rational numbers, as novel cases of natural number. This suggests that percent values are not differentiated from natural numbers; a conceptual shift from the natural numbers to the rational numbers has not yet occurred. This is most surprising, considering people are inundated…

  12. Optically switchable natural silk

    SciTech Connect

    Krasnov, Igor Müller, Martin; Krekiehn, Nicolai R.; Jung, Ulrich; Magnussen, Olaf M.; Krywka, Christina; Zillohu, Ahnaf U.; Strunskus, Thomas; Elbahri, Mady

    2015-03-02

    An optically active bio-material is created by blending natural silk fibers with photoisomerizable chromophore molecules—azobenzenebromide (AzBr). The material converts the energy of unpolarized light directly into mechanical work with a well-defined direction of action. The feasibility of the idea to produce optically driven microsized actuators on the basis of bio-material (silk) is proven. The switching behavior of the embedded AzBr molecules was studied in terms of UV/Vis spectroscopy. To test the opto-mechanical properties of the modified fibers and the structural changes they undergo upon optically induced switching, single fiber X-ray diffraction with a micron-sized synchrotron radiation beam was combined in situ with optical switching as well as with mechanical testing and monitoring. The crystalline regions of silk are not modified by the presence of the guest molecules, hence occupy only the amorphous part of the fibers. It is shown that chromophore molecules embedded into fibers can be reversibly switched between the trans and cis conformation by illumination with light of defined wavelengths. The host fibers respond to this switching with a variation of the internal stress. The amplitude of the mechanical response is independent of the applied external stress and its characteristic time is shorter than the relaxation time of the usual mechanical response of silk.

  13. Prospects for natural SUSY

    NASA Astrophysics Data System (ADS)

    Kim, J. S.; Rolbiecki, K.; Ruiz, R.; Tattersall, J.; Weber, T.

    2016-11-01

    As we anticipate the first results of the 2016 run, we assess the discovery potential of the LHC to "natural supersymmetry." To begin with, we explore the region of the model parameter space that can be excluded with various center-of-mass energies (13 TeV and 14 TeV) and different luminosities (20 fb-1 , 100 fb-1 , 300 fb-1 and 3000 fb-1 ). We find that the bounds at 95% C.L. on stops vary from mt˜1≳800 GeV expected this summer to mt˜1≳1500 GeV at the end of the high luminosity run, while gluino bounds are expected to range from mg ˜≳1700 GeV to mg ˜≳2500 GeV over the same time period. However, more pessimistically, we find that if no signal begins to appear this summer, only a very small region of parameter space can be discovered with 5 σ significance. For this conclusion to change, we find that both theoretical and systematic uncertainties will need to be significantly reduced.

  14. Nature, nurture, and expertise

    PubMed Central

    Plomin, Robert; Shakeshaft, Nicholas G.; McMillan, Andrew; Trzaskowski, Maciej

    2014-01-01

    Rather than investigating the extent to which training can improve performance under experimental conditions (‘what could be’), we ask about the origins of expertise as it exists in the world (‘what is’). We used the twin method to investigate the genetic and environmental origins of exceptional performance in reading, a skill that is a major focus of educational training in the early school years. Selecting reading experts as the top 5% from a sample of 10,000 12-year-old twins assessed on a battery of reading tests, three findings stand out. First, we found that genetic factors account for more than half of the difference in performance between expert and normal readers. Second, our results suggest that reading expertise is the quantitative extreme of the same genetic and environmental factors that affect reading performance for normal readers. Third, growing up in the same family and attending the same schools account for less than a fifth of the difference between expert and normal readers. We discuss implications and interpretations (‘what is inherited is DNA sequence variation’; ‘the abnormal is normal’). Finally, although there is no necessary relationship between ‘what is’ and ‘what could be’, the most far-reaching issues about the acquisition of expertise lie at the interface between them (‘the nature of nurture: from a passive model of imposed environments to an active model of shaped experience’). PMID:24948844

  15. SUSY naturalness without prejudice

    NASA Astrophysics Data System (ADS)

    Ghilencea, D. M.

    2014-05-01

    Unlike the Standard Model (SM), supersymmetric models stabilize the electroweak (EW) scale v at the quantum level and predict that v is a function of the TeV-valued SUSY parameters (γα) of the UV Lagrangian. We show that the (inverse of the) covariance matrix of the model in the basis of these parameters and the usual deviation δχ2 (from χmin2 of a model) automatically encode information about the "traditional" EW fine-tuning measuring this stability, provided that the EW scale v ˜mZ is indeed regarded as a function v =v(γ). It is known that large EW fine-tuning may signal an incomplete theory of soft terms and can be reduced when relations among γα exist (due to GUT symmetries, etc.). The global correlation coefficient of this matrix can help one investigate if such relations are present. An upper bound on the usual EW fine-tuning measure ("in quadrature") emerges from the analysis of the δχ2 and the s-standard deviation confidence interval by using v =v(γ) and the theoretical approximation (loop order) considered for the calculation of the observables. This upper bound avoids subjective criteria for the "acceptable" level of EW fine-tuning for which the model is still "natural."

  16. Natural rubber latex allergy.

    PubMed

    Deval, Ravi; Ramesh, V; Prasad, G B K S; Jain, Arun Kumar

    2008-01-01

    Natural rubber latex (NRL) is a ubiquitous allergen as it is a component of > 40,000 products in everyday life. Latex allergy might be attributed to skin contact or inhalation of latex particles. Latex allergy is an IgE-mediated hypersensitivity to NRL, presenting a wide range of clinical symptoms such as angioedema, swelling, cough, asthma, and anaphylactic reactions. Until 1979, latex allergy appeared only as type IV delayed hypersensitivity; subsequently, the proportion of different allergy types drifted towards type IV contact allergy reactions. Several risk factors for sensitization to NRL are already known and well documented. Some authors have established a positive correlation between a history of multiple surgical interventions, atopy, spina bifida malformation, and latex allergy incidence. We suspect an increase in latex allergy incidence in association with increased atopy and sensitivity to environmental allergens in the industrial population. It is often postulated in literature that the groups of workers at risk for this allergy are essentially workers in the latex industry and healthcare professionals. In this population, direct internal and mucosal contact with NRL medical devices may be the route of sensitization as factors such as the number of procedures and use of NRL materials (catheters and tubes) were associated with increased risk of latex sensitization and allergy.

  17. Natural gas conversion process

    SciTech Connect

    Not Available

    1991-01-01

    The main objective is to design and operate a laboratory apparatus for the catalytic reforming of natural gas in order to provide data for a large-scale process. To accelerate the assembly and calibration of this equipment, a request has been made to the Lawrence Berkeley Laboratory for assistance, under the DOE's Industrial Visitor Exchange Program. Pr. Heinz Heinemann (Catalysis), Dr. John Apps (Geochemistry) and Dr. Robert Fulton (Mechanical Engineering) have expressed interest in supporting our request. Pr. Heinemann's recent results on the conversion of Petroleum Coke residues into CO2 and H2 mixtures using highly basic metal oxides catalysts, similar to ours, are very encouraging regarding the possibility of converting the Coke residue on our catalyst into Syngas in the Regenerator/riser, as proposed. To minimize Coke formation in the vapor phase, by the Plasmapyrolytic Methane Conversion reactions, the experimental data of H. Drost et al. (Ref. 12) have been reviewed. Work is underway to design equipment for the safe and non-polluting disposal of the two gaseous product streams of the flow loop. 2 refs.

  18. Nature of orchestral noise.

    PubMed

    O'Brien, Ian; Wilson, Wayne; Bradley, Andrew

    2008-08-01

    Professional orchestral musicians are at risk of exposure to excessive noise when at work. This is an industry-wide problem that threatens not only the hearing of orchestral musicians but also the way orchestras operate. The research described in this paper recorded noise levels within a professional orchestra over three years in order to provide greater insight to the orchestral noise environment; to guide future research into orchestral noise management and hearing conservation strategies; and to provide a basis for the future education of musicians and their managers. Every rehearsal, performance, and recording from May 2004 to May 2007 was monitored, with the woodwind, brass, and percussion sections monitored in greatest detail. The study recorded dBALEQ and dBC peak data, which are presented in graphical form with accompanying summarized data tables. The findings indicate that the principal trumpet, first and third horns, and principal trombone are at greatest risk of exposure to excessive sustained noise levels and that the percussion and timpani are at greatest risk of exposure to excessive peak noise levels. However, the findings also strongly support the notion that the true nature of orchestral noise is a great deal more complex than this simple statement would imply.

  19. Nature's Autonomous Oscillators

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Yee, J.-H.; Mayr, M.; Schnetzler, R.

    2012-01-01

    Nonlinearity is required to produce autonomous oscillations without external time dependent source, and an example is the pendulum clock. The escapement mechanism of the clock imparts an impulse for each swing direction, which keeps the pendulum oscillating at the resonance frequency. Among nature's observed autonomous oscillators, examples are the quasi-biennial oscillation and bimonthly oscillation of the Earth atmosphere, and the 22-year solar oscillation. The oscillations have been simulated in numerical models without external time dependent source, and in Section 2 we summarize the results. Specifically, we shall discuss the nonlinearities that are involved in generating the oscillations, and the processes that produce the periodicities. In biology, insects have flight muscles, which function autonomously with wing frequencies that far exceed the animals' neural capacity; Stretch-activation of muscle contraction is the mechanism that produces the high frequency oscillation of insect flight, discussed in Section 3. The same mechanism is also invoked to explain the functioning of the cardiac muscle. In Section 4, we present a tutorial review of the cardio-vascular system, heart anatomy, and muscle cell physiology, leading up to Starling's Law of the Heart, which supports our notion that the human heart is also a nonlinear oscillator. In Section 5, we offer a broad perspective of the tenuous links between the fluid dynamical oscillators and the human heart physiology.

  20. Freedom in nature

    NASA Astrophysics Data System (ADS)

    Hájíček, P.

    2009-09-01

    The paper starts with the proposal that the cause of the apparent insolubility of the free-will problem are several popular but strongly metaphysical notions and hypotheses. To reduce the metaphysics, some ideas are borrowed from physics. A concept of event causality is discussed. The importance of Hume’s Principle of Causality is stressed and his Principle of Causation is weakened. The key concept of the paper, the so-called relative freedom, is also suggested by physics. It is a kind of freedom that can be observed everywhere in nature. Turning to biology, incomplete knowledge is defined for all organisms. They cope with the problem by Popper’s trial and error processes. One source of their success is the relative freedom of choice from the basic option ranges: mutations, motions and neural connections. Finally, the conjecture is adopted that communicability can be used as a criterion of consciousness and free will is defined as a conscious version of relative freedom. The resulting notion is logically self-consistent and it describes an observable phenomenon that agrees with our experience.