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Sample records for superdormant spores increased

  1. Activate to eradicate: inhibition of Clostridium difficile spore outgrowth by the synergistic effects of osmotic activation and nisin.

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    Michelle M Nerandzic

    Full Text Available BACKGROUND: Germination is the irreversible loss of spore-specific properties prior to outgrowth. Because germinating spores become more susceptible to killing by stressors, induction of germination has been proposed as a spore control strategy. However, this strategy is limited by superdormant spores that remain unaffected by germinants. Harsh chemicals and heat activation are effective for stimulating germination of superdormant spores but are impractical for use in a hospital setting, where Clostridium difficile spores present a challenge. Here, we tested whether osmotic activation solutes will provide a mild alternative for stimulation of superdormant C. difficile spores in the presence of germinants as previously demonstrated in several species of Bacillus. In addition, we tested the hypothesis that the limitations of superdormancy can be circumvented with a combined approach using nisin, a FDA-approved safe bacteriocin, to inhibit outgrowth of germinated spores and osmotic activation solutes to enhance outgrowth inhibition by stimulating superdormant spores. PRINCIPAL FINDINGS: Exposure to germination solution triggered ~1 log(10 colony forming units (CFU of spores to germinate, and heat activation increased the spores that germinated to >2.5 log(10CFU. Germinating spores, in contrast to dormant spores, became susceptible to inhibition by nisin. The presence of osmotic activation solutes did not stimulate germination of superdormant C. difficile spores exposed to germination solution. But, in the absence of germination solution, osmotic activation solutes enhanced nisin inhibition of superdormant spores to >3.5 log(10CFU. The synergistic effects of osmotic activation solutes and nisin were associated with loss of membrane integrity. CONCLUSIONS: These findings suggest that the synergistic effects of osmotic activation and nisin bypass the limitations of germination as a spore control strategy, and might be a novel method to safely and

  2. Induction of Rhizopus oryzae germination under starvation using host metabolites increases spore susceptibility to heat stress.

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    Turgeman, Tidhar; Kakongi, Nathan; Schneider, Avishai; Vinokur, Yakov; Teper-Bamnolker, Paula; Carmeli, Shmuel; Levy, Maggie; Skory, Christopher D; Lichter, Amnon; Eshel, Dani

    2014-03-01

    Sweetpotato is a nutritional source worldwide. Soft rot caused by Rhizopus spp. is a major limiting factor in the storage of produce, rendering it potentially unsafe for human consumption. In this study, Rhizopus oryzae was used to develop a concept of postharvest disease control by weakening the pathogen through induction of spore germination under starvation conditions. We isolated the sweetpotato active fractions (SPAFs) that induce spore germination and used them at a low dose to enhance spore weakening caused by starvation. Germination in SPAF at 1 mg/ml weakened the pathogen spores by delaying their ability to form colonies on rich media and by increasing their sensitivity to heat stress. The weakening effect was also supported by reduced metabolic activity, as detected by Alarmar Blue fluorescent dye assays. Spores incubated with SPAF at 1 mg/ml showed DNA fragmentation in some of their nuclei, as observed by TUNEL assay. In addition, these spores exhibited changes in ultrastructural morphology (i.e., shrinkage of germ tubes, nucleus deformation, and vacuole formation) which are hallmarks of programmed cell death. We suggest that induction of spore germination under starvation conditions increases their susceptibility to stress and, therefore, might be considered a new strategy for pathogen control.

  3. VeA of Aspergillus niger increases spore dispersing capacity by impacting conidiophore architecture.

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    Wang, Fengfeng; Dijksterhuis, Jan; Wyatt, Timon; Wösten, Han A B; Bleichrodt, Robert-Jan

    2015-01-01

    Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger maximizes the diameter of the vesicle and the spore chain length. The length and width of the conidiophore stalk and vesicle were reduced nearly twofold in a ΔveA strain. The latter implies a fourfold reduced surface area to develop chains of spores. Over and above this, the conidial chain length was approximately fivefold reduced. The calculated 20-fold reduction in formation of conidia by ΔveA fits the 8- to 17-fold decrease in counted spore numbers. Notably, morphology of the ΔveA conidiophores of A. niger was very similar to that of wild-type Aspergillus sydowii. This suggests that VeA is key in conidiophore architecture diversity in the fungal kingdom. The finding that biomass formation of the A. niger ΔveA strain was reduced twofold shows that VeA not only impacts dispersion capacity but also colonization capacity of A. niger.

  4. Do small spores disperse further than large spores?

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    Norros, Veera; Rannik, Ullar; Hussein, Tareq; Petäjä, Tuukka; Vesala, Timo; Ovaskainen, Otso

    2014-06-01

    In species that disperse by airborne propagules an inverse relationship is often assumed between propagule size and dispersal distance. However, for microscopic spores the evidence for the relationship remains ambiguous. Lagrangian stochastic dispersion models that have been successful in predicting seed dispersal appear to predict similar dispersal for all spore sizes up to -40 microm diameter. However, these models have assumed that spore size affects only the downwards drift of particles due to gravitation and have largely omitted the highly size-sensitive deposition process to surfaces such as forest canopy. On the other hand, they have assumed that spores are certain to deposit when the air parcel carrying them touches the ground. Here, we supplement a Lagrangian stochastic dispersion model with a mechanistic deposition model parameterized by empirical deposition data for 1-10 microm spores. The inclusion of realistic deposition improved the ability of the model to predict empirical data on the dispersal of a wood-decay fungus (aerodynamic spore size 3.8 microm). Our model predicts that the dispersal of 1-10 microm spores is in fact highly sensitive to spore size, with 97-98% of 1 microm spores but only 12-58% of 10-microm spores dispersing beyond 2 km in the simulated range of wind and canopy conditions. Further, excluding the assumption of certain deposition at the ground greatly increased the expected dispersal distances throughout the studied spore size range. Our results suggest that by evolutionary adjustment of spore size, release height and timing of release, fungi and other organisms with microscopic spores can change the expected distribution of dispersal locations markedly. The complex interplay of wind and canopy conditions in determining deposition resulted in some counterintuitive predictions, such as that spores disperse furthest under intermediate wind, providing intriguing hypotheses to be tested empirically in future studies.

  5. Spore stage expression of a vegetative insecticidal gene increase toxicity of Bacillus thuringiensis subsp. aizawai SP41 against Spodoptera exigua.

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    Thamthiankul Chankhamhaengdecha, S; Tantichodok, A; Panbangred, Watanalai

    2008-09-10

    To enhance the toxicity of the Bacillus thuringiensis subsp. aizawai strain SP41 (SP41), the vegetative insecticidal protein (Vip) gene vip3A from SP41 was redirected to the sporulation stage by replacing its native promoter with the strong promoter P19 of the cry11Aa operon. Compared to the wild type, SP41 with PVIP (vip3A with its native promoter and ter) had the relative expression ratios of 457, 548, and 290 at 8, 14, and 20 h of cultivation, respectively, as measured by quantitative reverse transcription polymerase chain reaction (PCR). SP41 transformed by P19VIP (vip3A controlled by P19 promoter with vip3A ter) showed higher expressions (23, 2055, 1831) at the same time points. SP41 with P19VIP20 (vip3A controlled by P19 promoter and containing P20 and operon ter) had the lowest expression levels (3, 11, 9) at any time point. SDS-PAGE analysis of proteins in the culture supernatant of the P19VIP at 8, 14, and 20 h demonstrated a significant increase in Vip3A at the sporulation stage. Using the surface contamination bioassay, the 50% lethal concentration (LC(50)) of whole culture of PVIP, P19VIP, and P19VIP20 at 20 and 48 h of cultivation against Spodoptera exigua larvae were (68.3, 21.2, and 60.2 microg cm(-2)) and (69.8, 41.8, and 74.6 microg cm(-2)), respectively, compared with 86.6 and 104.4 microg cm(-2) for SP41. The results showed that Vip from P19VIP, expressed at spore stage at 20 and 48 h, can increase the toxicity of SP41 for 4.1- and 2.5-fold, respectively.

  6. Effects of meteorological conditions on spore plumes

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    Burch, M.; Levetin, E.

    2002-05-01

    Fungal spores are an ever-present component of the atmosphere, and have long been known to trigger asthma and hay fever symptoms in sensitive individuals. The atmosphere around Tulsa has been monitored for airborne spores and pollen with Burkard spore traps at several sampling stations. This study involved the examination of the hourly spore concentrations on days that had average daily concentrations near 50,000 spores/m3 or greater. Hourly concentrations of Cladosporium, Alternaria, Epicoccum, Curvularia, Pithomyces, Drechslera, smut spores, ascospores, basidiospores, other, and total spores were determined on 4 days at three sites and then correlated with hourly meteorological data including temperature, rainfall, wind speed, dew point, air pressure, and wind direction. On each of these days there was a spore plume, a phenomenon in which spore concentrations increased dramatically over a very short period of time. Spore plumes generally occurred near midday, and concentrations were seen to increase from lows around 20,000 total spores/m3 to highs over 170,000 total spores/m3 in 2 h. Multiple regression analysis of the data indicated that increases in temperature, dew point, and air pressure correlated with the increase in spore concentrations, but no single weather variable predicted the appearance of a spore plume. The proper combination of changes in these meteorological parameters that result in a spore plume may be due to the changing weather conditions associated with thunderstorms, as on 3 of the 4 days when spore plumes occurred there were thunderstorms later that evening. The occurrence of spore plumes may have clinical significance, because other studies have shown that sensitization to certain spore types can occur during exposure to high spore concentrations.

  7. Effects of steam autoclave treatment on Geobacillus stearothermophilus spores.

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    Huesca-Espitia, L C; Suvira, M; Rosenbeck, K; Korza, G; Setlow, B; Li, W; Wang, S; Li, Y-Q; Setlow, P

    2016-11-01

    To determine the mechanism of autoclave killing of Geobacillus stearothermophilus spores used in biological indicators (BIs) for steam autoclave sterilization, and rates of loss of spore viability and a spore enzyme used in BIs. Spore viability, dipicolinic acid (DPA) release, nucleic acid staining, α-glucosidase activity, protein structure and mutagenesis were measured during autoclaving of G. stearothermophilus spores. Loss of DPA and increases in spore core nucleic acid staining were slower than loss of spore viability. Spore core α-glucosidase was also lost more slowly than spore viability, although soluble α-glucosidase in spore preparations was lost more rapidly. However, spores exposed to an effective autoclave sterilization lost all viability and α-glucosidase activity. Apparently killed autoclaved spores were not recovered by artificial germination in supportive media, much spore protein was denatured during autoclaving, and partially killed autoclave-treated spore preparations did not acquire mutations. These results indicate that autoclave-killed spores cannot be revived, spore killing by autoclaving is likely by protein damage, and spore core α-glucosidase activity is lost more slowly than spore viability. This work provides insight into the mechanism of autoclave killing of spores of an organism used in BIs, and that a spore enzyme in a BI is more stable to autoclaving than spore viability. © 2016 The Society for Applied Microbiology.

  8. Spore Resistance Properties.

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    Setlow, Peter

    2014-10-01

    Spores of various Bacillus and Clostridium species are among the most resistant life forms known. Since the spores of some species are causative agents of much food spoilage, food poisoning, and human disease, and the spores of Bacillus anthracis are a major bioweapon, there is much interest in the mechanisms of spore resistance and how these spores can be killed. This article will discuss the factors involved in spore resistance to agents such as wet and dry heat, desiccation, UV and γ-radiation, enzymes that hydrolyze bacterial cell walls, and a variety of toxic chemicals, including genotoxic agents, oxidizing agents, aldehydes, acid, and alkali. These resistance factors include the outer layers of the spore, such as the thick proteinaceous coat that detoxifies reactive chemicals; the relatively impermeable inner spore membrane that restricts access of toxic chemicals to the spore core containing the spore's DNA and most enzymes; the low water content and high level of dipicolinic acid in the spore core that protect core macromolecules from the effects of heat and desiccation; the saturation of spore DNA with a novel group of proteins that protect the DNA against heat, genotoxic chemicals, and radiation; and the repair of radiation damage to DNA when spores germinate and return to life. Despite their extreme resistance, spores can be killed, including by damage to DNA, crucial spore proteins, the spore's inner membrane, and one or more components of the spore germination apparatus.

  9. Photometric immersion refractometry of bacterial spores.

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    Gerhardt, P; Beaman, T C; Corner, T R; Greenamyre, J T; Tisa, L S

    1982-01-01

    Photometric immersion refractometry was used to determine the average apparent refractive index (n) of five types of dormant Bacillus spores representing a 600-fold range in moist-heat resistance determined as a D100 value. The n of a spore type increased as the molecular size of various immersion solutes decreased. For comparison of the spore types, the n of the entire spore and of the isolated integument was determined by use of bovine serum albumin, which is excluded from permeating into them. The n of the sporoplast (the structures bounded by the outer pericortex membrane) was determined by use of glucose, which was shown to permeate into the spore only as deeply as the pericortex membrane. Among the various spore types, an exponential increase in the heat resistance correlated with the n of the entire spore and of the sporoplast, but not of the isolated perisporoplast integument. Correlation of the n with the solids content of the entire spore provided a method of experimentally obtaining the refractive index increment (dn/dc), which was constant for the various spore types and enables the calculation of solids and water content from an n. Altogether, the results showed that the total water content is distributed unequally within the dormant spore, with less water in the sporoplast than in the perisporoplast integument, and that the sporoplast becomes more refractile and therefore more dehydrated as the heat resistance becomes greater among the various spore types. PMID:6802796

  10. Electron Beam Irradiation Dose Dependently Damages the Bacillus Spore Coat and Spore Membrane

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    S. E. Fiester

    2012-01-01

    Full Text Available Effective control of spore-forming bacilli begs suitable physical or chemical methods. While many spore inactivation techniques have been proven effective, electron beam (EB irradiation has been frequently chosen to eradicate Bacillus spores. Despite its widespread use, there are limited data evaluating the effects of EB irradiation on Bacillus spores. To study this, B. atrophaeus spores were purified, suspended in sterile, distilled water, and irradiated with EB (up to 20 kGy. Irradiated spores were found (1 to contain structural damage as observed by electron microscopy, (2 to have spilled cytoplasmic contents as measured by spectroscopy, (3 to have reduced membrane integrity as determined by fluorescence cytometry, and (4 to have fragmented genomic DNA as measured by gel electrophoresis, all in a dose-dependent manner. Additionally, cytometry data reveal decreased spore size, increased surface alterations, and increased uptake of propidium iodide, with increasing EB dose, suggesting spore coat alterations with membrane damage, prior to loss of spore viability. The present study suggests that EB irradiation of spores in water results in substantial structural damage of the spore coat and inner membrane, and that, along with DNA fragmentation, results in dose-dependent spore inactivation.

  11. Study of increasing spore content of Beauveria bassiana%提高白僵菌孢子含量的研究

    Institute of Scientific and Technical Information of China (English)

    刘杰; 陈荣; 孙惠杰

    2001-01-01

    Adding some protein of Antheraea pernyi pupae as the replacement of powder of bean cake and meize flour into Beauveria bassiana raw material and culturing solid in three degrees in iron plate can significantly increase the spores content of Beauveria bassiana,reduce the cost and raise the effect.%在生产白僵菌的原料中,加入一定量的柞蚕蛹蛋白代替豆饼粉或玉米粉,采用铁盘三级固体培养,可显著提高白僵菌的含孢量、缩短生产周期、降低成本、提高对害虫的杀伤速率和效果。

  12. NASA Facts: SporeSat

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    Martinez, Andres; Cappuccio, Gelsomina; Tomko, David

    2013-01-01

    SporeSat is an autonomous, free-flying three-unit (3U) spacecraft that will be used to conduct scientific experiments to gain a deeper knowledge of the mechanisms of plant cell gravity sensing. SporeSat is being developed through a partnership between NASAs Ames Research Center and the Department of Agricultural and Biological Engineering at Purdue University. Amani Salim and Jenna L. Rickus are the Purdue University Principal Investigators. The SporeSat mission will be flown using a 3U nanosatellite weighing approximately 12 pounds and measuring 14 inches long by 4 inches wide by 4 inches tall. SporeSat will utilize flight-proven spacecraft technologies demonstrated on prior Ames nanosatellite missions such as PharmaSat and OrganismOrganic Exposure to Orbital Stresses (OOREOS) as well as upgrades that increase the hardware integration capabilities with SporeSat science instrumentation. In addition, the SporeSat science payload will serve as a technology platform to evaluate new microsensor technologies for enabling future fundamental biology missions.

  13. Phospholipase Cδ regulates germination of Dictyostelium spores

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    Van Haastert Peter JM

    2001-12-01

    Full Text Available Abstract Background Many eukaryotes, including plants and fungi make spores that resist severe environmental stress. The micro-organism Dictyostelium contains a single phospholipase C gene (PLC; deletion of the gene has no effect on growth, cell movement and differentiation. In this report we show that PLC is essential to sense the environment of food-activated spores. Results Plc-null spores germinate at alkaline pH, reduced temperature or increased osmolarity, conditions at which the emerging amoebae can not grow. In contrast, food-activated wild-type spores return to dormancy till conditions in the environment allow growth. The analysis of inositol 1,4,5-trisphosphate (IP3 levels and the effect of added IP3 uncover an unexpected mechanism how PLC regulates spore germination: i deletion of PLC induces the enhanced activity of an IP5 phosphatase leading to high IP3 levels in plc-null cells; ii in wild-type spores unfavourable conditions inhibit PLC leading to a reduction of IP3 levels; addition of exogenous IP3 to wild-type spores induces germination at unfavourable conditions; iii in plc-null spores IP3 levels remain high, also at unfavourable environmental conditions. Conclusions The results imply that environmental conditions regulate PLC activity and that IP3 induces spore germination; the uncontrolled germination of plc-null spores is not due to a lack of PLC activity but to the constitutive activation of an alternative IP3-forming pathway.

  14. A method for the determination of bacterial spore DNA content based on isotopic labelling, spore germination and diphenylamine assay; ploidy of spores of several Bacillus species.

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    Hauser, P M; Karamata, D

    1992-01-01

    A reliable method for measuring the spore DNA content, based on radioactive DNA labelling, spore germination in absence of DNA replication and diphenylamine assay, was developed. The accuracy of the method, within 10-15%, is adequate for determining the number of chromosomes per spore, provided that the genome size is known. B subtilis spores were shown to be invariably monogenomic, while those of larger bacilli Bacillus megaterium, Bacillus cereus and Bacillus thuringiensis, often, if not invariably, contain two genomes. Attempts to modify the spore DNA content of B subtilis by altering the richness of the sporulation medium, the sporulation conditions (liquid or solid medium), or by mutation, were apparently unsuccessful. An increase of spore size with medium richness, not accompanied by an increase in DNA content, was observed. The implication of the apparently species-specific spore ploidy and the influence of the sporulation conditions on spore size and shape are discussed.

  15. Hydrazine inactivates bacillus spores

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    Schubert, Wayne; Plett, G. A.; Yavrouian, A. H.; Barengoltz, J.

    2005-01-01

    Planetary Protection places requirements on the maximum number of viable bacterial spores that may be delivered by a spacecraft to another solar system body. Therefore, for such space missions, the spores that may be found in hydrazine are of concern. A proposed change in processing procedures that eliminated a 0.2 um filtration step propmpted this study to ensure microbial contamination issue existed, especially since no information was found in the literature to substantiate bacterial spore inactivation by hydrazine.

  16. Comparison of hand hygiene procedures for removing Bacillus cereus spores.

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    Sasahara, Teppei; Hayashi, Shunji; Hosoda, Kouichi; Morisawa, Yuji; Hirai, Yoshikazu

    2014-01-01

    Bacillus cereus is a spore-forming bacterium. B. cereus occasionally causes nosocomial infections, in which hand contamination with the spores plays an important role. Therefore, hand hygiene is the most important practice for controlling nosocomial B. cereus infections. This study aimed to determine the appropriate hand hygiene procedure for removing B. cereus spores. Thirty volunteers' hands were experimentally contaminated with B. cereus spores, after which they performed 6 different hand hygiene procedures. We compared the efficacy of the procedures in removing the spores from hands. The alcohol-based hand-rubbing procedures scarcely removed them. The soap washing procedures reduced the number of spores by more than 2 log10. Extending the washing time increased the spore-removing efficacy of the washing procedures. There was no significant difference in efficacy between the use of plain soap and antiseptic soap. Handwashing with soap is appropriate for removing B. cereus spores from hands. Alcohol-based hand-rubbing is not effective.

  17. Detecting Cortex Fragments During Bacterial Spore Germination.

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    Francis, Michael B; Sorg, Joseph A

    2016-06-25

    The process of endospore germination in Clostridium difficile, and other Clostridia, increasingly is being found to differ from the model spore-forming bacterium, Bacillus subtilis. Germination is triggered by small molecule germinants and occurs without the need for macromolecular synthesis. Though differences exist between the mechanisms of spore germination in species of Bacillus and Clostridium, a common requirement is the hydrolysis of the peptidoglycan-like cortex which allows the spore core to swell and rehydrate. After rehydration, metabolism can begin and this, eventually, leads to outgrowth of a vegetative cell. The detection of hydrolyzed cortex fragments during spore germination can be difficult and the modifications to the previously described assays can be confusing or difficult to reproduce. Thus, based on our recent report using this assay, we detail a step-by-step protocol for the colorimetric detection of cortex fragments during bacterial spore germination.

  18. Cryopreservation of fern spores

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    Spore banks for ferns are analogous to seed banks for angiosperms and provide a promising ex situ conservation tool because large quantities of germplasm with high genetic variation can be conserved in a small space with low economic and technical costs. Ferns produce two types of spores with very ...

  19. Initiation of bacterial spore germination.

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    Vary, J C; Halvorson, H O

    1968-04-01

    To investigate the problem of initiation in bacterial spore germination, we isolated, from extracts of dormant spores of Bacillus cereus strain T and B. licheniformis, a protein that initiated spore germination when added to a suspension of heat-activated spores. The optimal conditions for initiatory activity of this protein (the initiator) were 30 C in 0.01 to 0.04 m NaCl and 0.01 m tris(hydroxymethyl)aminomethane (pH 8.5). The initiator was inhibited by phosphate but required two co-factors, l-alanine (1/7 of K(m) for l-alanine-inhibited germination) and nicotinamide adenine dinucleotide (1.25 x 10(-4)m). In the crude extract, the initiator activity was increased 3.5-fold by heating the extract at 65 C for 10 min, but the partially purified initiator preparation was completely heat-sensitive (65 C for 5 min). Heat stability could be conferred on the purified initiator by adding 10(-3)m dipicolinic acid. A fractionation of this protein that excluded l-alanine dehydrogenase and adenosine deaminase from the initiator activity was developed. The molecular weight of the initiator was estimated as 7 x 10(4). The kinetics of germination in the presence of initiator were examined at various concentrations of l-alanine and nicotinamide adenine dinucleotide.

  20. Bacterial spores in food : how phenotypic variability complicates prediction of spore properties and bacterial behavior

    NARCIS (Netherlands)

    Eijlander, Robyn T.; Abee, Tjakko; Kuipers, Oscar P.

    2011-01-01

    Bacillus spores are a known cause of food spoilage and their increased resistance poses a major challenge in efficient elimination. Recent studies on bacterial cultures at the single cell level have revealed how minor differences in essential spore properties, such as core water content or germinant

  1. Bacterial spores in food: how phenotypic variability complicates prediction of spore properties and bacterial behavior

    NARCIS (Netherlands)

    Eijlander, R.T.; Abee, T.; Kuipers, O.P.

    2011-01-01

    Bacillus spores are a known cause of food spoilage and their increased resistance poses a major challenge in efficient elimination. Recent studies on bacterial cultures at the single cell level have revealed how minor differences in essential spore properties, such as core water content or germinant

  2. Source strength of fungal spore aerosolization from moldy building material

    Energy Technology Data Exchange (ETDEWEB)

    Gorny, Rafa L.; Reponen, Tiina; Grinshpun, Sergey A.; Willeke, Klaus [Cincinnati Univ., Dept. of Environmental Health, Cincinnati, OH (United States)

    2001-07-01

    The release of Aspergillus versicolor, Cladosporium cladosporioides, and Penicillium melinii spores from agar and ceiling tile surfaces was tested under different controlled environmental conditions using a newly designed and constructed aerosolization chamber. This study revealed that all the investigated parameters, such as fungal species, air velocity above the surface, texture of the surface, and vibration of contaminated material, affected the fungal spore release. It was found that typical indoor air currents can release up to 200 spores cm {sup -2} from surface with fungal spores during 30-min experiments. The release of fungal spores from smooth agar surfaces was found to be inadequate for accurately predicting the emission from rough ceiling tile surfaces because the air turbulence increases the spore release from a rough surface. A vibration of a frequency of 1Hz at a power level of 14W resulted in a significant increase in the spore release rate. The release appears to depend on the morphology of the fungal colonies grown on ceiling tile surfaces including the thickness of conidiophores, the length of spore chains, and the shape of spores. The spores were found to be released continuously during each 30-min experiment. However, the release rate was usually highest during the first few minutes of exposure to air currents and mechanical vibration. About 71-88% of the spores released during a 30-min interval became airborne during the first 10min. (Author)

  3. Spore development and nuclear inheritance in arbuscular mycorrhizal fungi

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    Hijri Mohamed

    2011-02-01

    Full Text Available Abstract Background A conventional tenet of classical genetics is that progeny inherit half their genome from each parent in sexual reproduction instead of the complete genome transferred to each daughter during asexual reproduction. The transmission of hereditary characteristics from parents to their offspring is therefore predictable, although several exceptions are known. Heredity in microorganisms, however, can be very complex, and even unknown as is the case for coenocytic organisms such as Arbuscular Mycorrhizal Fungi (AMF. This group of fungi are plant-root symbionts, ubiquitous in most ecosystems, which reproduce asexually via multinucleate spores for which sexuality has not yet been observed. Results We examined the number of nuclei per spore of four AMF taxa using high Z-resolution live confocal microscopy and found that the number of nuclei was correlated with spore diameter. We show that AMF have the ability, through the establishment of new symbioses, to pass hundreds of nuclei to subsequent generations of multinucleated spores. More importantly, we observed surprising heterogeneity in the number of nuclei among sister spores and show that massive nuclear migration and mitosis are the mechanisms by which AMF spores are formed. We followed spore development of Glomus irregulare from hyphal swelling to spore maturity and found that the spores reached mature size within 30 to 60 days, and that the number of nuclei per spores increased over time. Conclusions We conclude that the spores used for dispersal of AMF contain nuclei with two origins, those that migrate into the spore and those that arise by mitosis in the spore. Therefore, these spores do not represent a stage in the life cycle with a single nucleus, raising the possibility that AMF, unlike all other known eukaryotic organisms, lack the genetic bottleneck of a single-nucleus stage.

  4. Bryophyte spore germinability is inhibited by peatland substrates

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    Bu, Zhao-Jun; Li, Zhi; Liu, Li-Jie; Sundberg, Sebastian; Feng, Ya-Min; Yang, Yun-He; Liu, Shuang; Song, Xue; Zhang, Xing-Lin

    2017-01-01

    Bryophyte substrates and species may affect spore germination through allelopathy. Polytrichum strictum is currently expanding in peatlands in north-eastern China - is this an effect of its superior spore germinability or do its gametophytes have a stronger allelopathic effect than do Sphagnum? We conducted a spore burial experiment to test the effect of species identity, substrate and water table depth (WTD) on spore germinability and bryophyte allelopathic effect with P. strictum and two Sphagnum species (S. palustre and S. magellanicum). After 5 months of burial during a growing season, the spores were tested for germinability. Allelopathic effect of bryophyte substrates was assessed by the difference between spore germinability after being stored inside or outside the substrates. After burial, more than 90% of the spores lost their germinability across all three species due to ageing and allelopathy. Spore germinability differed among species, where the spores in S. palustre had a higher germination frequency than those in P. strictum. The three bryophytes maintained a higher germinability in Sphagnum than in Polytrichum hummocks, probably due to a stronger allelopathic effect of P. strictum. Water table drawdown by 10 cm increased germinability by more than 60% across the three species. The study indicates that P. strictum does not possess an advantage regarding spore germination but rather its gametophytes have a stronger allelopathic effect. Due to the weaker inhibitive effect of Sphagnum gametophytes, P. strictum may have a potential establishment superiority over Sphagnum in peatlands, in addition to a better drought tolerance, which may explain its current expansion.

  5. Chemical and morphological studies of bacterial spore formation. IV. The development of spore refractility.

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    YOUNG, I E; JAMES, P C

    1962-01-01

    From the stage of a completed membranous forespore to that of a fully ripened free spore, synchronously sporulating cells of a variant Bacillus cereus were studied by cytological and chemical methods. Particular attention was paid to the development of the three spore layers-cortex, coat, and exosporium-in relation to the forespore membrane. First, the cortex is laid down between the recently described (5) double layers of the forespore membrane. Then when the cortex is (1/3) fully formed, the spore coat and exosporium are laid down peripheral to the outer membrane layer covering the cortex. As these latter layers appear, the spores, previously dense by dark phase contrast, gradually "whiten" or show an increase in refractive index. With this whitening, calcium uptake commences, closely followed by the synthesis of dipicolinic acid and the process is terminated, an hour later, with the formation of a fully refractile spore. In calcium-deficient media, final refractility is lessened and dipicolinic acid is formed only in amounts proportional to the available calcium. If calcium is withheld during the period of uptake beyond a critical point, sporulating cells lose the ability to assimilate calcium and to form normal amounts of dipicolinic acid. The resulting deficient spores are liberated from the sporangia but are unstable in water suspensions. Unlike ripe spores, they do not react violently to acid hydrolysis and, in thin sections, their cytoplasmic granules continue to stain with lead solutions.

  6. Fifth international fungus spore conference

    Energy Technology Data Exchange (ETDEWEB)

    Timberlake, W.E.

    1993-04-01

    This folio contains the proceedings of the Fifth International Fungal Spore Conference held August 17-21, 1991 at the Unicoi State Park at Helen, Georgia. The volume contains abstracts of each oral presentation as well as a collection of abstracts describing the poster sessions. Presentations were organized around the themes (1) Induction of Sporulation, (2) Nuclear Division, (3) Spore Formation, (4) Spore Release and Dispersal, and (4) Spore Germination.

  7. Anthrax Spores under a microscope

    Science.gov (United States)

    2003-01-01

    Anthrax spores are inactive forms of Bacillus anthracis. They can survive for decades inside a spore's tough protective coating; they become active when inhaled by humans. A result of NASA- and industry-sponsored research to develop small greenhouses for space research is the unique AiroCide TiO2 system that kills anthrax spores and other pathogens.

  8. Self-inhibition of spore germination via reactive oxygen in the fungus Cladosporium cucumerinum, causal agent of cucurbit scab

    Science.gov (United States)

    Cladosporium cucumerinum spore germination in vitro depended on spore suspension density. Different fungal isolates displayed maximum germination at different spore concentrations. For one isolate, maximum spore density was observed at both 18 and 25 °C, although germination percentage increased sli...

  9. Aerodynamics of puffball mushroom spore dispersal

    Science.gov (United States)

    Amador, Guillermo; Barberie, Alex; Hu, David

    2012-11-01

    Puffball mushrooms Lycoperdon are spherical fungi that release a cloud of spores in response to raindrop impacts. In this combined experimental and theoretical study, we elucidate the aerodynamics of this unique impact-based spore-dispersal. We characterize live puffball ejections by high speed video, the geometry and elasticity of their shells by cantilever experiments, and the packing fraction and size of their spores by scanning electron microscope. We build a dynamically similar puffball mimic composed of a tied-off latex balloon filled with baby powder and topped with a 1-cm slit. A jet of powder is elicited by steady lateral compression of the mimic between two plates. The jet height is a bell-shaped function of force applied, with a peak of 18 cm at loads of 45 N. We rationalize the increase in jet height with force using Darcy's Law: the applied force generates an overpressure maintained by the air-tight elastic membrane. Pressure is relieved as the air travels through the spore interstitial spaces, entrains spores, and exits through the puffball orifice. This mechanism demonstrates how powder-filled elastic shells can generate high-speed jets using energy harvested from rain.

  10. Spore: Spawning Evolutionary Misconceptions?

    Science.gov (United States)

    Bean, Thomas E.; Sinatra, Gale M.; Schrader, P. G.

    2010-10-01

    The use of computer simulations as educational tools may afford the means to develop understanding of evolution as a natural, emergent, and decentralized process. However, special consideration of developmental constraints on learning may be necessary when using these technologies. Specifically, the essentialist (biological forms possess an immutable essence), teleological (assignment of purpose to living things and/or parts of living things that may not be purposeful), and intentionality (assumption that events are caused by an intelligent agent) biases may be reinforced through the use of computer simulations, rather than addressed with instruction. We examine the video game Spore for its depiction of evolutionary content and its potential to reinforce these cognitive biases. In particular, we discuss three pedagogical strategies to mitigate weaknesses of Spore and other computer simulations: directly targeting misconceptions through refutational approaches, targeting specific principles of scientific inquiry, and directly addressing issues related to models as cognitive tools.

  11. New Rapid Spore Assay

    Science.gov (United States)

    Kminek, Gerhard; Conley, Catharine

    2012-07-01

    The presentation will detail approved Planetary Protection specifications for the Rapid Spore Assay for spacecraft components and subsystems. Outlined will be the research and studies on which the specifications were based. The research, funded by ESA and NASA/JPL, was conducted over a period of two years and was followed by limited cleanroom studies to assess the feasibility of this assay during spacecraft assembly.

  12. Spore coat architecture of Clostridium novyi NT spores.

    Science.gov (United States)

    Plomp, Marco; McCaffery, J Michael; Cheong, Ian; Huang, Xin; Bettegowda, Chetan; Kinzler, Kenneth W; Zhou, Shibin; Vogelstein, Bert; Malkin, Alexander J

    2007-09-01

    Spores of the anaerobic bacterium Clostridium novyi NT are able to germinate in and destroy hypoxic regions of tumors in experimental animals. Future progress in this area will benefit from a better understanding of the germination and outgrowth processes that are essential for the tumorilytic properties of these spores. Toward this end, we have used both transmission electron microscopy and atomic force microscopy to determine the structure of both dormant and germinating spores. We found that the spores are surrounded by an amorphous layer intertwined with honeycomb parasporal layers. Moreover, the spore coat layers had apparently self-assembled, and this assembly was likely to be governed by crystal growth principles. During germination and outgrowth, the honeycomb layers, as well as the underlying spore coat and undercoat layers, sequentially dissolved until the vegetative cell was released. In addition to their implications for understanding the biology of C. novyi NT, these studies document the presence of proteinaceous growth spirals in a biological organism.

  13. Clostridium difficile spore-macrophage interactions: spore survival.

    Directory of Open Access Journals (Sweden)

    Daniel Paredes-Sabja

    Full Text Available BACKGROUND: Clostridium difficile is the main cause of nosocomial infections including antibiotic associated diarrhea, pseudomembranous colitis and toxic megacolon. During the course of Clostridium difficile infections (CDI, C. difficile undergoes sporulation and releases spores to the colonic environment. The elevated relapse rates of CDI suggest that C. difficile spores has a mechanism(s to efficiently persist in the host colonic environment. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we provide evidence that C. difficile spores are well suited to survive the host's innate immune system. Electron microscopy results show that C. difficile spores are recognized by discrete patchy regions on the surface of macrophage Raw 264.7 cells, and phagocytosis was actin polymerization dependent. Fluorescence microscopy results show that >80% of Raw 264.7 cells had at least one C. difficile spore adhered, and that ∼60% of C. difficile spores were phagocytosed by Raw 264.7 cells. Strikingly, presence of complement decreased Raw 264.7 cells' ability to phagocytose C. difficile spores. Due to the ability of C. difficile spores to remain dormant inside Raw 264.7 cells, they were able to survive up to 72 h of macrophage infection. Interestingly, transmission electron micrographs showed interactions between the surface proteins of C. difficile spores and the phagosome membrane of Raw 264.7 cells. In addition, infection of Raw 264.7 cells with C. difficile spores for 48 h produced significant Raw 264.7 cell death as demonstrated by trypan blue assay, and nuclei staining by ethidium homodimer-1. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that despite efficient recognition and phagocytosis of C. difficile spores by Raw 264.7 cells, spores remain dormant and are able to survive and produce cytotoxic effects on Raw 264.7 cells.

  14. Inhibition of spore germination of Alternaria tenuis by sulfur dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Couey, H.M.

    1962-08-01

    As a part of a continuing study of SO/sub 2/ fumigation of table grapes, the effect of SO/sub 2/ on spores of an isolate of A. tenuis Auct. causing decay of table grapes was determined. The amount of SO/sub 2/ required to inhibit completely spore germination depended on availability of moisture and the temperature. At 20/sup 0/C, wet spores required 20-min exposure to 100 ppm SO/sub 2/ to prevent germination, but spores equilibrated at 90% relative humidity (RH) required 10-min exposure to 1000 ppm SO/sub 2/. Dry spores at 60% RH were unaffected by a 20-min exposure to 4000 ppm SO/sub 2/. Increasing the temperature in the range 5-20/sup 0/C increased effectiveness of the SO/sub 2/ treatment. A comparison of Alternaria with Botrytis cinerea Fr. (studied earlier) showed that wet spores of these organisms were about equally sensitive to SO/sub 2/, but that dry Alternaria spores were more resistant to SO/sub 2/ than dry Botrytis spores under comparable conditions.

  15. Improvement of immunodetection of bacterial spore antigen by ultrasonic cavitation.

    Science.gov (United States)

    Borthwick, Kathryn A J; Love, Tracey E; McDonnell, Martin B; Coakley, W Terence

    2005-11-15

    Ultrasonic cavitation was employed to enhance sensitivity of bacterial spore immunoassay detection, specifically, enzyme-linked immunosorbent assay (ELISA) and resonant mirror (RM) sensing. Bacillus spore suspensions were exposed to high-power ultrasound in a tubular sonicator operated at 267 kHz in both batch and flow modes. The sonicator was designed to deliver high output power and is in a form that can be cooled efficiently to avoid thermal denaturation of antigen. The 30-s batch and cooled flow (0.3 mL/min) sonication achieved an approximately 20-fold increase in ELISA sensitivity compared to unsonicated spores by ELISA. RM sensing of sonicated spores achieved detection sensitivity of approximately 10(6) spores/mL, whereas unsonicated spores were undetectable at the highest concentration tested. Improvements in detection were associated with antigen released from the spores. Equilibrium temperature increase in the tubular sonicator was limited to 14 K after 30 min and was maintained for 6 h with cooling and flow (0.3 mL/min). The work described here demonstrates the utility of the tubular sonicator for the improvement in the sensitivity of the detection of spores and its suitability as an in-line component of a rapid detection system.

  16. The Role of the Electrostatic Force in Spore Adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eunhyea [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Lee, Ida [University of Tennessee, Knoxville (UTK); Tsouris, Costas [ORNL

    2010-01-01

    Electrostatic force is investigated as one of the components of the adhesion force between Bacillus thuringiensis (Bt) spores and planar surfaces. The surface potentials of a Bt spore and a mica surface are experimentally obtained using a combined atomic force microscopy (AFM)-scanning surface potential microscopy technique. On the basis of experimental information, the surface charge density of the spores is estimated at 0.03 {micro}C/cm{sup 2} at 20% relative humidity and decreases with increasing humidity. The Coulombic force is introduced for the spore-mica system (both charged, nonconductive surfaces), and an electrostatic image force is introduced to the spore-gold system because gold is electrically conductive. The Coulombic force for spore-mica is repulsive because the components are similarly charged, while the image force for the spore-gold system is attractive. The magnitude of both forces decreases with increasing humidity. The electrostatic forces are added to other force components, e.g., van der Waals and capillary forces, to obtain the adhesion force for each system. The adhesion forces measured by AFM are compared to the estimated values. It is shown that the electrostatic (Coulombic and image) forces play a significant role in the adhesion force between spores and planar surfaces.

  17. Fern spore longevity in saline water: can sea bottom sediments maintain a viable spore bank?

    Science.gov (United States)

    de Groot, G Arjen; During, Heinjo

    2013-01-01

    Freshwater and marine sediments often harbor reservoirs of plant diaspores, from which germination and establishment may occur whenever the sediment falls dry. Therewith, they form valuable records of historical inter- and intraspecific diversity, and are increasingly exploited to facilitate diversity establishment in new or restored nature areas. Yet, while ferns may constitute a considerable part of a vegetation's diversity and sediments are known to contain fern spores, little is known about their longevity, which may suffer from inundation and--in sea bottoms--salt stress. We tested the potential of ferns to establish from a sea or lake bottom, using experimental studies on spore survival and gametophyte formation, as well as a spore bank analysis on sediments from a former Dutch inland sea. Our experimental results revealed clear differences among species. For Asplenium scolopendrium and Gymnocarpium dryopteris, spore germination was not affected by inundated storage alone, but decreased with rising salt concentrations. In contrast, for Asplenium trichomanes subsp. quadrivalens germination decreased following inundation, but not in response to salt. Germination rates decreased with time of storage in saline water. Smaller and less viable gametophytes were produced when saline storage lasted for a year. Effects on germination and gametophyte development clearly differed among genotypes of A. scolopendrium. Spore bank analyses detected no viable spores in marine sediment layers. Only two very small gametophytes (identified as Thelypteris palustris via DNA barcoding) emerged from freshwater sediments. Both died before maturation. We conclude that marine, and likely even freshwater sediments, will generally be of little value for long-term storage of fern diversity. The development of any fern vegetation on a former sea floor will depend heavily on the deposition of spores onto the drained land by natural or artificial means of dispersal.

  18. Meteorological factors associated with abundance of airborne fungal spores over natural vegetation

    Science.gov (United States)

    Crandall, Sharifa G.; Gilbert, Gregory S.

    2017-08-01

    The abundance of airborne fungal spores in agricultural and urban settings increases with greater air temperature, relative humidity, or precipitation. The same meteorological factors that affect temporal patterns in spore abundance in managed environments also vary spatially across natural habitats in association with differences in vegetation structure. Here we investigated how temporal and spatial variation in aerial spore abundance is affected by abiotic (weather) and biotic (vegetation) factors as a foundation for predicting how fungi may respond to changes in weather and land-use patterns. We measured the phenology of airborne fungal spores across a mosaic of naturally occurring vegetation types at different time scales to describe (1) how spore abundance changes over time, (2) which local meteorological variables are good predictors for airborne spore density, and (3) whether spore abundance differs across vegetation types. Using an air volumetric vacuum sampler, we collected spore samples at 3-h intervals over a 120-h period in a mixed-evergreen forest and coastal prairie to measure diurnal, nocturnal, and total airborne spore abundance across vegetation types. Spore samples were also collected at weekly and monthly intervals in mixed-evergreen forest, redwood forest, and maritime chaparral vegetation types from 12 field sites across two years. We found greater airborne spore densities during the wetter winter months compared to the drier summer months. Mean total spore abundance in the mixed-evergreen forest was twice than in the coastal prairie, but there were no significant differences in total airborne spore abundance among mixed-evergreen forest, redwood forest, and maritime chaparral vegetation types. Weekly and monthly peaks in airborne spore abundance corresponded with rain events and peaks in soil moisture. Overall, temporal patterns in meteorological factors were much more important in determining airborne fungal spore abundance than the

  19. Ultraviolet irradiation of DNA complexed with. alpha. /. beta. -type small, acid-soluble proteins from spores of Bacillus or Clostridium species makes spore photoproduct but not thymine dimers

    Energy Technology Data Exchange (ETDEWEB)

    Nicholson, W.L.; Setlow, B.; Setlow, P. (Univ. of Connecticut Health Center, Farmington (United States))

    1991-10-01

    UV irradiation of complexes of DNA and an {alpha}/{beta}-type small, acid-soluble protein (SASP) from Bacillus subtilis spores gave decreasing amounts of pyrimidine dimers and increasing amounts of spore photoproduct as the SASP/DNA ratio was increased. The yields of pyrimidine dimers and spore photoproduct were < 0.2% and 8% of total thymine, respectively, when DNA saturated with SASP was irradiated at 254 nm with 30 kJ/m{sup 2}; in the absence of SASP the yields were reversed - 4.5% and 0.3%, respectively. Complexes of DNA with {alpha}/{beta}-type SASP from Bacillus cereus, Bacillus megaterium, or Clostridium bifermentans spores also gave spore photoproduct upon UV irradiation. However, incubation of these SASPs with DNA under conditions preventing complex formation or use of mutant SASPs that do not form complexes did not affect the photoproducts formed in vitro. These results suggest that the UV photochemistry of bacterial spore DNA in vivo is due to the binding of {alpha}/{beta}-type SASP, a binding that is known to cause a change in DNA conformation in vitro from the B form to the A form. The yields of spore photoproduct in vitro were significantly lower than in vivo, perhaps because of the presence of substances other than SASP in spores. It is suggested that as these factors diffuse out in the first minutes of spore germination, spore photoproduct yields become similar to those observed for irradiation of SASP/DNA complexes in vitro.

  20. Hydrazine vapor inactivates Bacillus spores

    Science.gov (United States)

    Schubert, Wayne W.; Engler, Diane L.; Beaudet, Robert A.

    2016-05-01

    NASA policy restricts the total number of bacterial spores that can remain on a spacecraft traveling to any planetary body which might harbor life or have evidence of past life. Hydrazine, N2H4, is commonly used as a propellant on spacecraft. Hydrazine as a liquid is known to inactivate bacterial spores. We have now verified that hydrazine vapor also inactivates bacterial spores. After Bacillus atrophaeus ATCC 9372 spores deposited on stainless steel coupons were exposed to saturated hydrazine vapor in closed containers, the spores were recovered from the coupons, serially diluted, pour plated and the surviving bacterial colonies were counted. The exposure times required to reduce the spore population by a factor of ten, known as the D-value, were 4.70 ± 0.50 h at 25 °C and 2.85 ± 0.13 h at 35 °C. These inactivation rates are short enough to ensure that the bioburden of the surfaces and volumes would be negligible after prolonged exposure to hydrazine vapor. Thus, all the propellant tubing and internal tank surfaces exposed to hydrazine vapor do not contribute to the total spore count.

  1. Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components. [heat sensitivity of bacterial spores

    Science.gov (United States)

    Campbell, J. E.; Reyes, A. L.; Wehby, A. J.; Crawford, R. G.; Wimsatt, J. C.; Peeler, J. T.

    1973-01-01

    The mechanism for thermal inactivation of bacterial spores under moist or dry heat was studied. Experimental conditions were established relating to spore loss of heat resistance and loss of optical density as a measure of the rate and extent of germination in spore suspensions. Events occurring during germination were correlated with phase darkening (refractility and non-refractility of spores), stainability characteristics of heat and non-heat treated spores, morphological characteristics, and studies on swelling of spores by an increase in packed cell volume.

  2. Spore Dispersion of Tricholoma matsutake at a Pinus densiflora Stand in Korea.

    Science.gov (United States)

    Park, Hyun; Ka, Kang-Hyeon

    2010-09-01

    The spore of Tricholoma matsutake is considered to be the starting point of the mushroom growth cycle, but the mechanism of mycelial development from the spore stage is not yet clarified. In this study, we tried to measure how far the spores of T. matsutake disperse from a fruiting body located at a Pinus densiflora stand in Korea. We established 16 slide glasses coated with glycerin near a fruiting body in four directions separated by four different distance intervals within a mushroom productive stand after removing all other fruiting bodies from three plots. The number of dispersed spores increased with time from the first day (475 spores/cm(2)) to the fourth day (836 spores/cm(2)) after the pileus opened. The number of spores dispersed downward was about 1.5 times greater than that dispersed toward the ridge. The number of dispersed spores decreased exponentially as the distance from each fruiting body increased. More than 95% of the spores dropped within a meter from the fruiting body, with 75% dropping within 0.5 m. Even so, the number of spores dispersed over 5 m from the fruiting body was more than 50 million when considering the total number of spores produced by a fruiting body is about 5 billion.

  3. Breaking and Characteristics of Ganoderma Lucidum Spores by High Speed Entrifugal Shearing Pulverizer

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The spores of Ganoderma lucidum were ground and broken to ultrafine particles by high speed centrifugal shearing(HSCS) pulverizer. The characteristics of Ganoderma lucidum spores were analyzed by scanning electron microscope (SEM), Fourier transform infrared spectrophotometry (FTIR). Ultraviolet-visible pectrophotometer was used to determine the extraction ratio of aqueous solubility polysaccharide between the raw and broken spores. The immunological function on the mice before and after the breaking of spores was investigated. The experimental results show that after being ground, the sporoderm-broken ratio reachs 100%,the original active ingredients of ganoderma lucidum spores do not change, and the extraction ratio of aqueous solubility polysaccharide is greatly increased by 40.08%. The broken spores show much higher immunological activity comparing with original spores of Ganoderma lucidum.

  4. Spore Coat Architecture of Clostridium novyi-NT spores

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; McCafferey, J; Cheong, I; Huang, X; Bettegowda, C; Kinzler, K; Zhou, S; Vogelstein, B; Malkin, A

    2007-05-07

    Spores of the anaerobic bacterium Clostridium novyi-NT are able to germinate in and destroy hypoxic regions of tumors in experimental animals. Future progress in this area will benefit from a better understanding of the germination and outgrowth processes that are essential for the tumorilytic properties of these spores. Towards this end, we have used both transmission electron microscopy and atomic force microscopy to determine the structure of dormant as well as germinating spores. We found that the spores are surrounded by an amorphous layer intertwined with honeycomb parasporal layers. Moreover, the spore coat layers had apparently self-assembled and this assembly was likely to be governed by crystal growth principles. During germination and outgrowth, the honeycomb layers as well as the underlying spore coat and undercoat layers sequentially dissolved until the vegetative cell was released. In addition to their implications for understanding the biology of C. novyi-NT, these studies document the presence of proteinaceous growth spirals in a biological organism.

  5. Genetic Factors and Host Traits Predict Spore Morphology for a Butterfly Pathogen

    Directory of Open Access Journals (Sweden)

    Jacobus C. de Roode

    2013-08-01

    Full Text Available Monarch butterflies (Danaus plexippus throughout the world are commonly infected by the specialist pathogen Ophryocystis elektroscirrha (OE. This protozoan is transmitted when larvae ingest infectious stages (spores scattered onto host plant leaves by infected adults. Parasites replicate internally during larval and pupal stages, and adult monarchs emerge covered with millions of dormant spores on the outsides of their bodies. Across multiple monarch populations, OE varies in prevalence and virulence. Here, we examined geographic and genetic variation in OE spore morphology using clonal parasite lineages derived from each of four host populations (eastern and western North America, South Florida and Hawaii. Spores were harvested from experimentally inoculated, captive-reared adult monarchs. Using light microscopy and digital image analysis, we measured the size, shape and color of 30 replicate spores per host. Analyses examined predictors of spore morphology, including parasite source population and clone, parasite load, and the following host traits: family line, sex, wing area, and wing color (orange and black pigmentation. Results showed significant differences in spore size and shape among parasite clones, suggesting genetic determinants of morphological variation. Spore size also increased with monarch wing size, and monarchs with larger and darker orange wings tended to have darker colored spores, consistent with the idea that parasite development depends on variation in host quality and resources. We found no evidence for effects of source population on variation in spore morphology. Collectively, these results provide support for heritable variation in spore morphology and a role for host traits in affecting parasite development.

  6. Simulation modeling of anthrax spore dispersion in a bioterrorism incident.

    Science.gov (United States)

    Reshetin, Vladimir P; Regens, James L

    2003-12-01

    Recent events have increased awareness of the risk posed by terrorist attacks. Bacillus anthracis has resurfaced in the 21st century as a deadly agent of bioterrorism because of its potential for causing massive civilian casualties. This analysis presents the results of a computer simulation of the dispersion of anthrax spores in a typical 50-story, high-rise building after an intentional release during a bioterrorist incident. The model simulates aerosol dispersion in the case of intensive, small-scale convection, which equalizes the concentration of anthrax spores over the building volume. The model can be used to predict the time interval required for spore dispersion throughout a building after a terrorist attack in a high-rise building. The analysis reveals that an aerosol release of even a relatively small volume of anthrax spores during a terrorist incident has the potential to quickly distribute concentrations that are infectious throughout the building.

  7. Fed-batch production of gluconic acid by terpene-treated Aspergillus niger spores.

    Science.gov (United States)

    Ramachandran, Sumitra; Fontanille, Pierre; Pandey, Ashok; Larroche, Christian

    2008-12-01

    Aspergillus niger spores were used as catalyst in the bioconversion of glucose to gluconic acid. Spores produced by solid-state fermentation were treated with 15 different terpenes including monoterpenes and monoterpenoids to permeabilize and inhibit spore germination. It was found that spore membrane permeability is significantly increased by treatment with terpenoids when compared to monoterpenes. Best results were obtained with citral and isonovalal. Studies were carried out to optimize spores concentration (10(7)-10(10) spores/mL), terpene concentrations in the bioconversion medium and time of exposure (1-18 h) needed for permeabilization of spores. Fed-batch production of gluconate was done in a bioreactor with the best conditions [10(9) spores/mL of freeze-thawed spores treated with citral (3% v/v) for 5 h] followed by sequential additions of glucose powder and pH-regulated with a solution containing 2 mol/L of either NaOH or KOH. Bioconversion performance of the spore enzyme was compared with the commercial glucose oxidase at 50, 60, and 70 degrees C. Results showed that the spore enzyme was comparatively stable at 60 degrees C. It was also found that the spores could be reutilized for more than 14 cycles with almost similar reaction rate. Similar biocatalytic activity was rendered by spores even after its storage of 1 year at -20 degrees C. This study provided an experimental evidence of the significant catalytic role played by A. niger spore in bioconversion of glucose to gluconic acid with high yield and stability, giving protection to glucose oxidase.

  8. Recent advances in germination of Clostridium spores.

    Science.gov (United States)

    Olguín-Araneda, Valeria; Banawas, Saeed; Sarker, Mahfuzur R; Paredes-Sabja, Daniel

    2015-05-01

    Members of Clostridium genus are a diverse group of anaerobic spore-formers that includes several pathogenic species. Their anaerobic requirement enhances the importance of the dormant spore morphotype during infection, persistence and transmission. Bacterial spores are metabolically inactive and may survive for long times in the environment and germinate in presence of nutrients termed germinants. Recent progress with spores of several Clostridium species has identified the germinant receptors (GRs) involved in nutrient germinant recognition and initiation of spore germination. Signal transduction from GRs to the downstream effectors remains poorly understood but involves the release of dipicolinic acid. Two mechanistically different cortex hydrolytic machineries are present in Clostridium spores. Recent studies have also shed light into novel biological events that occur during spore formation (accumulation of transcriptional units) and transcription during early spore outgrowth. In summary, this review will cover all of the recent advances in Clostridium spore germination. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  9. Control of Bacillus licheniformis spores isolated from dairy materials in yogurt production.

    Science.gov (United States)

    Tanaka, Takashi; Ito, Akiko; Kamikado, Hideaki

    2012-01-01

    To determine the effects of sporulation temperature and period on Bacillus licheniformis spore heat resistance, B. licheniformis strain No.25 spores were sporulated at 30, 37, 42, or 50°C for 11 d and at 50°C for 1.7, 4, 7, or 11 d. The heat resistance of B. licheniformis strain No.25 spores at 110°C increased with an increase in the sporulation temperature. Spores sporulated at 50°C were 1.4-fold more heat resistant than those sporulated at 30°C. Furthermore, the heat resistance of B. licheniformis strain No.25 spores at 110°C increased with an increase in the sporulation period. Spores sporulated for 11 d were 5.3-fold more heat resistant than those sporulated for 1.7 d. The heat resistance of B. licheniformis strain No.25 spores at 110°C increased with increases in the sporulation temperature and sporulation period. The results presented in this study can be applied to the pasteurization process to control B. licheniformis spores. Pasteurization at 110°C for about 60sec. is effective in controlling B. licheniformis spores isolated from dairy materials in yogurt production.

  10. Vacuum-induced Mutations In Bacillus Subtilis Spores

    Science.gov (United States)

    Munakata, N.; Maeda, M.; Hieda, K.

    During irradiation experiments with vacuum-UV radiation using synchrotron sources, we made unexpected observation that Bacillus subtilis spores of several recombination-deficient strains lost colony-forming ability by the exposure to high vacuum alone. Since this suggested the possible injury in spore DNA, we looked for mutation induction using the spores of strains HA101 (wild-type repair capability) and TKJ6312 (excision and spore repair deficient) that did not lose survivability. It was found that the frequency of nalidixic-acid resistant mutation increased several times in both of these strains by the exposure to high vacuum (10e-4 Pa after 24 hours). The analysis of sequence changes in gyrA gene showed that the majority of mutations carried a unique allele (gyrA12) of tandem double-base substitutions from CA to TT. The observation has been extended to rifampicin resistant mutations, the majority of that carried substitutions from CA to TT or AT in rpoB gene. On the other hand, when the spores of strains PS578 and PS2319 (obtained from P. Setlow) that are defective in a group of small acidic proteins (alpha/beta-type SASP) were similarly treated, none of the mutants analyzed carried such changes. This suggests that the unique mutations might be induced by the interaction of small acidic proteins with spore DNA under forced dehydration. The results indicate that extreme vacuum causes severe damage in spore DNA, and provide additional constraint to the long-term survival of bacterial spores in the space environment.

  11. Measuring Total and Germinable Spore Populations

    Science.gov (United States)

    Noell, A.C.; Yung, P.T.; Yang, W.; Lee, C.; Ponce, A.

    2011-01-01

    It has been shown that bacterial endospores can be enumerated using a microscopy based assay that images the luminescent halos from terbium ions bound to dipicolinic acid, a spore specific chemical marker released upon spore germination. Further development of the instrument has simplified it towards automation while at the same time improving image quality. Enumeration of total spore populations has also been developed allowing measurement of the percentage of viable spores in any population by comparing the germinable/culturable spores to the total. Percentage viability will allow a more quantitative comparison of the ability of spores to survive across a wide range of extreme environments.

  12. Significance of air humidity and air velocity for fungal spore release into the air

    Science.gov (United States)

    Pasanen, A.-L.; Pasanen, P.; Jantunen, M. J.; Kalliokoski, P.

    Our previous field studies have shown that the presence of molds in buildings does not necessarily mean elevated airborne spore counts. Therefore, we investigated the release of fungal spores from cultures of Aspergillus fumigatus, Penicillium sp. and Cladosporium sp. at different air velocities and air humidities. Spores of A. fumigatus and Penicillium sp. were released from conidiophores already at air velocity of 0.5 ms -1, whereas Cladosporium spores required at least a velocity of 1.0 ms -1. Airborne spore counts of A. fumigatus and Penicillium sp. were usually higher in dry than moist air, being minimal at relative humidities (r.h.) above 70%, while the effect of r.h. on the release of Cladosporium sp. was ambivalent. The geometric mean diameter of released spores increased when the r.h. exceeded a certain level which depends on fungal genus. Thus, spores of all three fungi were hygroscopic but the hygroscopicity of various spores appeared at different r.h.-ranges. This study indicates that spore release is controlled by external factors and depends on fungal genus which can be one reason for considerable variation of airborne spore counts in buildings with mold problems.

  13. Impact of spore biology on the rate of kill and suppression of resistance in Bacillus anthracis.

    Science.gov (United States)

    Drusano, G L; Okusanya, O O; Okusanya, A O; van Scoy, B; Brown, D L; Fregeau, C; Kulawy, R; Kinzig, M; Sörgel, F; Heine, H S; Louie, A

    2009-11-01

    Bacillus anthracis is complex because of its spore form. The spore is invulnerable to antibiotic action. It also has an impact on the emergence of resistance. We employed the hollow-fiber infection model to study the impacts of different doses and schedules of moxifloxacin on the total-organism population, the spore population, and the subpopulations of vegetative- and spore-phase organisms that were resistant to moxifloxacin. We then generated a mathematical model of the impact of moxifloxacin, administered by continuous infusion or once daily, on vegetative- and spore-phase organisms. The ratio of the rate constant for vegetative-phase cells going to spore phase (K(vs)) to the rate constant for spore-phase cells going to vegetative phase (K(sv)) determines the rate of organism clearance. The continuous-infusion drug profile is more easily sensed as a threat; the K(vs)/K(sv) ratio increases at lower drug exposures (possibly related to quorum sensing). This movement to spore phase protects the organism but makes the emergence of resistance less likely. Suppression of resistance requires a higher level of drug exposure with once-daily administration than with a continuous infusion, a difference that is related to vegetative-to-spore (and back) transitioning. Spore biology has a major impact on drug therapy and resistance suppression. These findings explain why all drugs of different classes have approximately the same rate of organism clearance for Bacillus anthracis.

  14. Environmental microbiology as related to planetary quarantine. [water activity and temperature effects on bacterial spore survival

    Science.gov (United States)

    Pflug, I. J.

    1972-01-01

    The survival of Bacillus subtilis var. niger spores suspended in solutions of sucrose and glycerol at calculated water activities and varying temperatures was studied. The overall results indicated that as the water activity of the liquid decreased from .99 to .85, the heat resistance of the spores increased. The nature of the substance controlling the water activity, and the history of the spores prior to treatment also had an affect on their heat resistance.

  15. Responses of Bacillus subtilis spores to space environment: results from experiments in space.

    Science.gov (United States)

    Horneck, G

    1993-02-01

    Onboard of several spacecrafts (Apollo 16, Spacelab 1, LDEF), spores of Bacillus subtilis were exposed to selected parameters of space, such as space vacuum, different spectral ranges of solar UV-radiation and cosmic rays, applied separately or in combination, and we have studied their survival and genetic changes after retrieval. The spores survive extended periods of time in space--up to several years--, if protected against the high influx of solar UV-radiation. Water desorption caused by the space vacuum leads to structural changes of the DNA; the consequences are an increased mutation frequency and altered photobiological properties of the spores. UV-effects, such as killing and mutagenesis, are augmented, if the spores are in space vacuum during irradiation. Vacuum-specific photoproducts which are different from the 'spore photoproduct' may cause the synergistic response of spores to the simultaneous action of UV and vacuum. The experiments provide an experimental test of certain steps of the panspermia hypothesis.

  16. Molecular Kinetics of Reviving Bacterial Spores

    OpenAIRE

    2013-01-01

    Bacterial spores can remain dormant for years, yet they possess a remarkable potential to rapidly resume a vegetative life form. Here, we identified a distinct phase at the onset of spore outgrowth, designated the ripening period. This transition phase is exploited by the germinating spore for molecular reorganization toward elongation and subsequent cell division. We have previously shown that spores of different ages, kept under various temperatures, harbor dissimilar molecular reservoirs (...

  17. Water properties in fern spores: sorption characteristics relating to water affinity, glassy states, and storage stability.

    Science.gov (United States)

    Ballesteros, Daniel; Walters, Christina

    2007-01-01

    Ex situ conservation of ferns may be accomplished by maintaining the viability of stored spores for many years. Storage conditions that maximize spore longevity can be inferred from an understanding of the behaviour of water within fern spores. Water sorption properties were measured in spores of five homosporeous species of ferns and compared with properties of pollen, seeds, and fern leaf tissue. Isotherms were constructed at 5, 25, and 45 degrees C and analysed using different physicochemical models in order to quantify chemical affinity and heat (enthalpy) of sorption of water in fern spores. Fern spores hydrate slowly but dry rapidly at ambient relative humidity. Low Brunauer-Emmet-Teller monolayer values, few water-binding sites according to the D'Arcy-Watt model, and limited solute-solvent compatibility according to the Flory-Huggins model suggest that fern spores have low affinity for water. Despite the low water affinity, fern spores demonstrate relatively high values of sorption enthalpy (DeltaH(sorp)). Parameters associated with binding sites and DeltaH(sorp) decrease with increasing temperature, suggesting temperature- and hydration-dependent changes in volume of spore macromolecules. Collectively, these data may relate to the degree to which cellular structures within fern spores are stabilized during drying and cooling. Water sorption properties within fern spores suggest that storage at subfreezing temperatures will give longevities comparable with those achieved with seeds. However, the window of optimum water contents for fern spores is very narrow and much lower than that measured in seeds, making precise manipulation of water content imperative for achieving maximum longevity.

  18. Non-Seasonal Variation of Airborne Aspergillus Spore Concentration in a Hospital Building

    Directory of Open Access Journals (Sweden)

    Michael Oberle

    2015-10-01

    Full Text Available Nosocomial fungal infections are gaining increased attention from infectiologists. An adequate investigation into the levels of airborne Aspergillus and other fungal spores in hospital settings, under normal conditions, is largely unknown. We monitored airborne spore contamination in a Swiss hospital building in order to establish a seasonally-dependent base-line level. Air was sampled using an impaction technique, twice weekly, at six different locations over one year. Specimens were seeded in duplicate on Sabouraud agar plates. Grown colonies were identified to genus levels. The airborne Aspergillus spore concentration was constantly low throughout the whole year, at a median level of 2 spores/m3 (inter-quartile range = IQR 1–4, and displayed no seasonal dependency. The median concentration of other fungal spores was higher and showed a distinct seasonal variability with the ambient temperature change during the different seasons: 82 spores/m3 (IQR 26–126 in summer and 9 spores/m3 (IQR 6–15 in winter. The spore concentration varied considerably between the six sampling sites in the building (10 to 26 spores/m3. This variability may explain the variability of study results in the literature.

  19. Changes in concentration of Alternaria and Cladosporium spores during summer storms

    Science.gov (United States)

    Grinn-Gofroń, Agnieszka; Strzelczak, Agnieszka

    2013-09-01

    Fungal spores are known to cause allergic sensitization. Recent studies reported a strong association between asthma symptoms and thunderstorms that could be explained by an increase in airborne fungal spore concentrations. Just before and during thunderstorms the values of meteorological parameters rapidly change. Therefore, the goal of this study was to create a predictive model for hourly concentrations of atmospheric Alternaria and Cladosporium spores on days with summer storms in Szczecin (Poland) based on meteorological conditions. For this study we have chosen all days of June, July and August (2004-2009) with convective thunderstorms. There were statistically significant relationships between spore concentration and meteorological parameters: positive for air temperature and ozone content while negative for relative humidity. In general, before a thunderstorm, air temperature and ozone concentration increased, which was accompanied by a considerable increase in spore concentration. During and after a storm, relative humidity increased while both air temperature ozone concentration along with spore concentrations decreased. Artificial neural networks (ANN) were used to assess forecasting possibilities. Good performance of ANN models in this study suggest that it is possible to predict spore concentrations from meteorological variables 2 h in advance and, thus, warn people with spore-related asthma symptoms about the increasing abundance of airborne fungi on days with storms.

  20. Isolating and Purifying Clostridium difficile Spores

    Science.gov (United States)

    Edwards, Adrianne N.; McBride, Shonna M.

    2016-01-01

    Summary The ability for the obligate anaerobe, Clostridium difficile, to form a metabolically dormant spore is critical for the survival of this organism outside of the host. This spore form is resistant to a myriad of environmental stresses, including heat, desiccation and exposure to disinfectants and antimicrobials. These intrinsic properties of spores allow C. difficile to survive long-term in an oxygenated environment, to be easily transmitted from host-to-host and to persist within the host following antibiotic treatment. Because of the importance of the spore form to the C. difficile lifecycle and treatment and prevention of C. difficile infection (CDI), the isolation and purification of spores are necessary to study the mechanisms of sporulation and germination, investigate spore properties and resistances, and for use in animal models of CDI. This chapter provides basic protocols, in vitro growth conditions and additional considerations for purifying C. difficile spores for a variety of downstream applications. PMID:27507337

  1. Scanning Surface Potential Microscopy of Spore Adhesion on Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ida [University of Tennessee, Knoxville (UTK); Chung, Eunhyea [Georgia Institute of Technology; Kweon, Hyojin [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Tsouris, Costas [ORNL

    2012-01-01

    The adhesion of spores of Bacillus anthracis - the cause of anthrax and a likely biological threat - to solid surfaces is an important consideration in cleanup after an accidental or deliberate release. However, because of safety concerns, directly studying B. anthracis spores with advanced instrumentation is problematic. As a first step, we are examining the electrostatic potential of Bacillus thuringiensis (Bt), which is a closely related species that is often used as a simulant to study B. anthracis. Scanning surface potential microscopy (SSPM), also known as Kelvin probe force microscopy (KPFM), was used to investigate the influence of relative humidity (RH) on the surface electrostatic potential of Bt that had adhered to silica, mica, or gold substrates. AFM/SSPM side-by-side images were obtained separately in air, at various values of RH, after an aqueous droplet with spores was applied on each surface and allowed to dry before measurements. In the SSPM images, a negative potential on the surface of the spores was observed compared with that of the substrates. The surface potential decreased as the humidity increased. Spores were unable to adhere to a surface with an extremely negative potential, such as mica.

  2. Surface tension propulsion of fungal spores.

    Science.gov (United States)

    Noblin, Xavier; Yang, Sylvia; Dumais, Jacques

    2009-09-01

    Most basidiomycete fungi actively eject their spores. The process begins with the condensation of a water droplet at the base of the spore. The fusion of the droplet onto the spore creates a momentum that propels the spore forward. The use of surface tension for spore ejection offers a new paradigm to perform work at small length scales. However, this mechanism of force generation remains poorly understood. To elucidate how fungal spores make effective use of surface tension, we performed a detailed mechanical analysis of the three stages of spore ejection: the transfer of energy from the drop to the spore, the work of fracture required to release the spore from its supporting structure and the kinetic energy of the spore after ejection. High-speed video imaging of spore ejection in Auricularia auricula and Sporobolomyces yeasts revealed that drop coalescence takes place over a short distance ( approximately 5 microm) and energy transfer is completed in less than 4 mus. Based on these observations, we developed an explicit relation for the conversion of surface energy into kinetic energy during the coalescence process. The relation was validated with a simple artificial system and shown to predict the initial spore velocity accurately (predicted velocity: 1.2 m s(-1); observed velocity: 0.8 m s(-1) for A. auricula). Using calibrated microcantilevers, we also demonstrate that the work required to detach the spore from the supporting sterigma represents only a small fraction of the total energy available for spore ejection. Finally, our observations of this unique discharge mechanism reveal a surprising similarity with the mechanics of jumping in animals.

  3. The Synergistic Effect of High Pressure CO2 and Nisin on Inactivation of Bacillus subtilis Spores in Aqueous Solutions

    Science.gov (United States)

    Rao, Lei; Wang, Yongtao; Chen, Fang; Liao, Xiaojun

    2016-01-01

    The inactivation effects of high pressure CO2 + nisin (simultaneous treatment of HPCD and nisin, HPCD + nisin), HPCD→nisin (HPCD was followed by nisin), and nisin→HPCD (nisin was followed by HPCD) treatments on Bacillus subtilis spores in aqueous solutions were compared. The spores were treated by HPCD at 6.5 or 20 MPa, 84–86°C and 0–30 min, and the concentration of nisin was 0.02%. Treated spores were examined for the viability, the permeability of inner membrane (IM) using flow cytometry method and pyridine-2, 6-dicarboxylic acid (DPA) release, and structural damage by transmission electron microscopy. A synergistic effect of HPCD + nisin treatment on inactivation of the spores was found, and the inactivation efficiency of the spores was HPCD + nisin > HPCD→nisin or nisin→HPCD. Moreover, HPCD + nisin caused higher IM permeability and DPA release of the spores than HPCD. A possible action mode of nisin-enhanced inactivation of the spores was suggested as that HPCD firstly damaged the coat and cortex of spores, and nisin penetrated into and acted on the IM of spores, which increased the damage to the IM of spores, and resulted in higher inactivation of the spores. PMID:27708639

  4. Permeabilization and inhibition of the germination of spores of Aspergillus niger for gluconic acid production from glucose.

    Science.gov (United States)

    Ramachandran, Sumitra; Fontanille, Pierre; Pandey, Ashok; Larroche, Christian

    2008-07-01

    In this study, the role of citral to permeabilize the spores of Aspergillus niger and replace sodium azide in the bioconversion medium was studied. Further, characterization of glucose oxidase of spores was carried out by exposing both permeabilized and unpermeabilized spores to different pressures (1, 2, 2.7 kb) and temperatures (60, 70, 80, 90 degrees C). Unpermeabilized spores after exposure to high temperatures were permeabilized by freezing before using as catalyst in the bioconversion reaction. Results showed that citral permeabilized the spores and could inhibit spore germination in the bioconversion medium. Rate of reaction was significantly increased from 1.5 to 4.35 g/Lh which was higher than the commercial glucose oxidase 2g/Lh). Glucose oxidase activity of A. niger was resistant to pressure. However, pressure treatment could not permeabilize them. Behaviour of fresh and permeabilized spores to temperature varied significantly. Glucose oxidase activity of fresh spores exposed to high temperature was unaffected at 70 degrees C till 15 min and 84% of relative activity was retained even after 1h at 70 degrees C while permeabilized spore got inactivated at 70 degrees C for 15 min, which followed the same pattern as commercial glucose oxidase. Cellular membrane integrity was lost due to permeabilization by freezing which resulted in heat-inactivation of glucose oxidase when spores were permeabilized before heat treatment. Thus, glucose oxidase of spore remains heat stable when unpermeabilized and active while permeabilized and its reaction rate is higher than the commercial glucose oxidase.

  5. Using Spores for Fusarium spp. Classification by MALDI-Based Intact Cell/Spore Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Wolfgang Winkler

    2012-01-01

    Full Text Available Fusarium is a widespread genus of filamentous fungi and a member of the soil microbial community. Certain subspecies are health threatening because of their mycotoxin production that affects the human and animal food chain. Thus, for early and effective pest control, species identification is of particular interest; however, differentiation on the subspecies level is challenging and time-consuming for this fungus. In the present study, we show the possibilities of intact cell mass spectrometry for spore analysis of 22 different Fusarium strains belonging to six Fusarium subspecies. We found that species differentiation is possible if mass spectrometric analyses are performed under well-defined conditions with fixed parameters. A critical point for analysis is a proper sample preparation of spores, which increases the quality of mass spectra with respect to signal intensity and m/z value variations. It was concluded that data acquistion has to be performed automatically; otherwise, user-specific variations are introduced generating data which cannot fit the existing datasets. Data that show clearly that matrix-assisted laser desorption ionization-based intact cell/intact spore mass spectrometry (IC/ISMS can be applied to differentiate closely related Fusarium spp. are presented. Results show a potential to build a database on Fusarium species for accurate species identification, for fast response in the case of infections in the cornfield. We furthermore demonstrate the high precision of our approach in classification of intact Fusarium species according to the location of their collection.

  6. Adenosine Monophosphate-Based Detection of Bacterial Spores

    Science.gov (United States)

    Kern, Roger G.; Chen, Fei; Venkateswaran, Kasthuri; Hattori, Nori; Suzuki, Shigeya

    2009-01-01

    A method of rapid detection of bacterial spores is based on the discovery that a heat shock consisting of exposure to a temperature of 100 C for 10 minutes causes the complete release of adenosine monophosphate (AMP) from the spores. This method could be an alternative to the method described in the immediately preceding article. Unlike that method and related prior methods, the present method does not involve germination and cultivation; this feature is an important advantage because in cases in which the spores are those of pathogens, delays involved in germination and cultivation could increase risks of infection. Also, in comparison with other prior methods that do not involve germination, the present method affords greater sensitivity. At present, the method is embodied in a laboratory procedure, though it would be desirable to implement the method by means of a miniaturized apparatus in order to make it convenient and economical enough to encourage widespread use.

  7. Lipoxygenase Activity Accelerates Programmed Spore Germination in Aspergillus fumigatus

    Directory of Open Access Journals (Sweden)

    Gregory J. Fischer

    2017-05-01

    Full Text Available The opportunistic human pathogen Aspergillus fumigatus initiates invasive growth through a programmed germination process that progresses from dormant spore to swollen spore (SS to germling (GL and ultimately invasive hyphal growth. We find a lipoxygenase with considerable homology to human Alox5 and Alox15, LoxB, that impacts the transitions of programmed spore germination. Overexpression of loxB (OE::loxB increases germination with rapid advance to the GL stage. However, deletion of loxB (ΔloxB or its signal peptide only delays progression to the SS stage in the presence of arachidonic acid (AA; no delay is observed in minimal media. This delay is remediated by the addition of the oxygenated AA oxylipin 5-hydroxyeicosatetraenoic acid (5-HETE that is a product of human Alox5. We propose that A. fumigatus acquisition of LoxB (found in few fungi enhances germination rates in polyunsaturated fatty acid-rich environments.

  8. Conservation of fern spores

    Science.gov (United States)

    Ferns are a diverse and important group of plants, but diversity of species and populations are at risk from increasing social pressures, loss of habitat and climate change. Ex situ conservation is a useful strategy to limit decline in genetic diversity and requires technologies to preserve fern ger...

  9. Friction and Adhesion Forces of Bacillus thuringiensis Spores on Planar Surfaces in Atmospheric Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kweon, Hyojin [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Tsouris, Costas [ORNL

    2011-01-01

    The kinetic friction force and the adhesion force of Bacillus thuringiensis spores on planar surfaces in atmospheric systems were studied using atomic force microscopy. The influence of relative humidity (RH) on these forces varied for different surface properties including hydrophobicity, roughness, and surface charge. The friction force of the spore was greater on a rougher surface than on mica, which is atomically flat. As RH increases, the friction force of the spores decreases on mica whereas it increases on rough surfaces. The influence of RH on the interaction forces between hydrophobic surfaces is not as strong as for hydrophilic surfaces. The friction force of the spore is linear to the sum of the adhesion force and normal load on the hydrophobic surface. The poorly defined surface structure of the spore and the adsorption of contaminants from the surrounding atmosphere are believed to cause a discrepancy between the calculated and measured adhesion forces.

  10. Oxidative damage involves in the inhibitory effect of nitric oxide on spore germination of Penicillium expansum.

    Science.gov (United States)

    Lai, Tongfei; Li, Boqiang; Qin, Guozheng; Tian, Shiping

    2011-01-01

    The effects of nitric oxide (NO) on spore germination of Penicillium expansum were investigated and a possible mechanism was evaluated. The results indicated that NO released by sodium nitroprusside (SNP) significantly suppressed fungal growth. With the use of an oxidant sensitive probe and Western blot analysis, an increased level of intracellular reactive oxygen species (ROS) and enhanced carbonylation damage were detected in spores of P. expansum under NO stress. Exogenous superoxide dismutase (SOD) and ascorbic acid (Vc) could increase the resistance of the spore to the inhibitory effect of NO. The activities of SOD and catalase (CAT), as well as ATP content in spores under NO stress were also lower than those in the control. We suggest that NO in high concentration induces the generation of ROS which subsequently causes severe oxidative damage to proteins crucial to the process of spore germination of P. expansum.

  11. Triggering germination represents a novel strategy to enhance killing of Clostridium difficile spores.

    Directory of Open Access Journals (Sweden)

    Michelle M Nerandzic

    Full Text Available BACKGROUND: Clostridium difficile is an anaerobic, spore-forming bacterium that is the most common cause of healthcare-associated diarrhea in developed countries. Control of C. difficile is challenging because the spores are resistant to killing by alcohol-based hand hygiene products, antimicrobial soaps, and most disinfectants. Although initiation of germination has been shown to increase susceptibility of spores of other bacterial species to radiation and heat, it was not known if triggering of germination could be a useful strategy to increase susceptibility of C. difficile spores to radiation or other stressors. PRINCIPAL FINDINGS: Here, we demonstrated that exposure of dormant C. difficile spores to a germination solution containing amino acids, minerals, and taurocholic acid resulted in initiation of germination in room air. Germination of spores in room air resulted in significantly enhanced killing by ultraviolet-C (UV-C radiation and heat. On surfaces in hospital rooms, application of germination solution resulted in enhanced eradication of spores by UV-C administered by an automated room decontamination device. Initiation of germination under anaerobic, but not aerobic, conditions resulted in increased susceptibility to killing by ethanol, suggesting that exposure to oxygen might prevent spores from progressing fully to outgrowth. Stimulation of germination also resulted in reduced survival of spores on surfaces in room air, possibly due to increased susceptibility to stressors such as oxygen and desiccation. CONCLUSIONS: Taken together, these data demonstrate that stimulation of germination could represent a novel method to enhance killing of spores by UV-C, and suggest the possible application of this strategy as a means to enhance killing by other agents.

  12. Bacterial spore germination and protein mobility.

    Science.gov (United States)

    Moir, Anne

    2003-10-01

    Fluorescence recovery after photobleaching (FRAP) of green fluorescent protein (GFP) has been used to report on protein mobility in single spores. Proteins found in dormant Bacillus spores are not mobile; however, mobility is restored when germination occurs and the core rehydrates. Spores of a cwlD mutant, in which the cortex is resistant to hydrolysis, are able to complete the earliest stages of germination in response to a specific germinant stimulus; in these circumstances, the protein in the spore remains immobile. Therefore, the earliest stages of spore germination, including loss of resistance to extreme heat and the complete release of the spore component dipicolinic acid, are achieved without the restoration of protein mobility.

  13. Bacillus subtilis Spores Germinate in the Chicken Gastrointestinal Tract▿

    OpenAIRE

    Stephen T Cartman; La Ragione, Roberto M.; Woodward, Martin J.

    2008-01-01

    A number of poultry probiotics contain bacterial spores. In this study, orally administered spores of Bacillus subtilis germinated in the gastrointestinal (GI) tracts of chicks. Furthermore, 20 h after spores were administered, vegetative cells outnumbered spores throughout the GI tract. This demonstrates that spore-based probiotics may function in this host through metabolically active mechanisms.

  14. Spore Cortex Hydrolysis Precedes Dipicolinic Acid Release during Clostridium difficile Spore Germination

    OpenAIRE

    2015-01-01

    Bacterial spore germination is a process whereby a dormant spore returns to active, vegetative growth, and this process has largely been studied in the model organism Bacillus subtilis. In B. subtilis, the initiation of germinant receptor-mediated spore germination is divided into two genetically separable stages. Stage I is characterized by the release of dipicolinic acid (DPA) from the spore core. Stage II is characterized by cortex degradation, and stage II is activated by the DPA released...

  15. Role of Spore Coat Proteins in the Resistance of Bacillus subtilis Spores to Caenorhabditis elegans Predation▿

    OpenAIRE

    2008-01-01

    Bacterial spores are resistant to a wide range of chemical and physical insults that are normally lethal for the vegetative form of the bacterium. While the integrity of the protein coat of the spore is crucial for spore survival in vitro, far less is known about how the coat provides protection in vivo against predation by ecologically relevant hosts. In particular, assays had characterized the in vitro resistance of spores to peptidoglycan-hydrolyzing enzymes like lysozyme that are also imp...

  16. Association and decontamination of Bacillus spores in a simulated drinking water system.

    Science.gov (United States)

    Morrow, J B; Almeida, J L; Fitzgerald, L A; Cole, K D

    2008-12-01

    The objective of this work was to elucidate the disinfectant susceptibility of Bacillus anthracis Sterne (BA) and a commercial preparation of Bacillus thuringiensis (BT) spores associated with a simulated drinking water system. Biofilms composed of indigenous water system bacteria were accumulated on copper and polyvinyl chloride (PVC) pipe material surfaces in a low-flow pipe loop and uniformly mixed tank reactor (CDC biofilm reactor). Application of a distributed shear during spore contact resulted in approximately a 1.0 and 1.6 log10 increase in the number of spores associated with copper and PVC surfaces, respectively. Decontamination of spores in both free suspension and after association with biofilm-conditioned pipe materials was attempted using free chlorine and monochloramine. Associated spores required 5- to 10-fold higher disinfectant concentrations to observe the same reduction of viable spores as in suspension. High disinfectant concentrations (103 mg/L free chlorine and 49 mg/L monochloramine) yielded less than a 2-log10 reduction in viable associated spores after 60 min. Spores associated with biofilms on copper surfaces consistently yielded higher Ct values than PVC.

  17. Sporicidal characteristics of heated dolomite powder against Bacillus subtilis spores.

    Science.gov (United States)

    Yasue, Syogo; Sawai, Jun; Kikuchi, Mikio; Nakakuki, Takahito; Sano, Kazuo; Kikuchi, Takahide

    2014-01-01

    Dolomite is a double salt composed of calcium carbonate (CaCO3) and magnesium carbonate (MgCO3). The heat treatment of CaCO3 and MgCO3 respectively generates calcium oxide (CaO) and magnesium oxide (MgO), which have antimicrobial activity. In this study, heated dolomite powder (HDP) slurry was investigated for its sporicidal activity against Bacillus subtilis ATCC 6633 spores. The B. subtilis spores used in this study were not affected by acidic (pH 1) or alkaline (pH 13) conditions, indicating that they were highly resistant. However, dolomite powder heated to 1000℃ for 1 h could kill B. subtilis spores, even at pH 12.7. Sporicidal activity was only apparent when the dolomite powder was heated to 800℃ or higher, and sporicidal activity increased with increases in the heating temperature. This temperature corresponded to that of the generation of CaO. We determined that MgO did not contribute to the sporicidal activity of HDP. To elucidate the sporicidal mechanism of the HDP against B. subtilis spores, the generation of active oxygen from HDP slurry was examined by chemiluminescence analysis. The generation of active oxygen increased when the HDP slurry concentration rose. The results suggested that, in addition to its alkalinity, the active oxygen species generated from HDP were associated with sporicidal activity.

  18. Distinction of broken cellular wall Ganoderma lucidum spores and G. lucidum spores using FTIR microspectroscopy

    Science.gov (United States)

    Chen, Xianliang; Liu, Xingcun; Sheng, Daping; Huang, Dake; Li, Weizu; Wang, Xin

    2012-11-01

    In this paper, FTIR microspectroscopy was used to identify broken cellular wall Ganoderma lucidum spores and G. lucidum spores. For IR spectra, broken cellular wall G. lucidum spores and G. lucidum spores were mainly different in the regions of 3000-2800, 1660-1600, 1400-1200 and 1100-1000 cm-1. For curve fitting, the results showed the differences in the protein secondary structures and the polysaccharide structures/content between broken cellular wall G. lucidum spores and G. lucidum spores. Moreover, the value of A1078/A1741 might be a potentially useful factor to distinguish broken cellular wall G. lucidum spores from G. lucidum spores. Additionally, FTIR microspectroscopy could identify broken cellular wall G. lucidum spores and G. lucidum spores accurately when it was combined with hierarchical cluster analysis. The result suggests FTIR microspectroscopy is very simple and efficient for distinction of broken cellular wall G. lucidum spores and G. lucidum spores. The result also indicates FTIR microspectroscopy may be useful for TCM identification.

  19. Spore-to-spore agar culture of the myxomycete Physarum globuliferum.

    Science.gov (United States)

    Liu, Pu; Wang, Qi; Li, Yu

    2010-02-01

    The ontogeny of the myxomycete Physarum globuliferum was observed on corn meal agar and hanging drop cultures without adding sterile oat flakes, bacteria or other microorganisms. Its complete life cycle including spore germination, myxamoebae, swarm cells, plasmodial development, and maturity of fructifications was demonstrated. Details of spore-to-spore development are described and illustrated.

  20. Anthrax Toxins in Context of Bacillus anthracis Spores and Spore Germination.

    Science.gov (United States)

    Cote, Christopher K; Welkos, Susan L

    2015-08-17

    The interaction of anthrax toxin or toxin components with B. anthracis spores has been demonstrated. Germinating spores can produce significant amounts of toxin components very soon after the initiation of germination. In this review, we will summarize the work performed that has led to our understanding of toxin and spore interactions and discuss the complexities associated with these interactions.

  1. Reticulate spore ornamentation in Strobilomyces

    Institute of Scientific and Technical Information of China (English)

    Ronald H.Petersen; John Dunlap; Karen W.Hughes

    2011-01-01

    Reticulate spore ornamentation in Strobilomyces (Boletaceae,Basidiomycotina) is visible under light microscopy (bright field and phase contrast) up to 1,500×.While some distinctions can be made at this magnification,ontogeny and fine structure of the ornamentation cannot be discerned.Scanning electron microscope images,conversely,reveal significant additional structure from which the ontogenetic process can be traced.Citing numerous New and Old World collections,this paper presents evidence distinguishing reticulate ornamentation ontogeny in these disjunct populations.

  2. Adhesion of Spores of Bacillus thuringiensis on a Planar Surface

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eunhyea [Georgia Institute of Technology; Kweon, Hyojin [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Lee, Ida [University of Tennessee, Knoxville (UTK); Joy, David Charles [ORNL; Palumbo, Anthony Vito [ORNL; Tsouris, Costas [ORNL

    2010-01-01

    Adhesion of spores of Bacillus thuringiensis (Bt) and spherical silica particles on surfaces was experimentally and theoretically investigated in this study. Topography analysis via atomic force microscopy (AFM) and electron microscopy indicates that Bt spores are rod shaped, {approx}1.3 {mu}m in length and {approx}0.8 {mu}m in diameter. The adhesion force of Bt spores and silica particles on gold-coated glass was measured at various relative humidity (RH) levels by AFM. It was expected that the adhesion force would vary with RH because the individual force components contributing to the adhesion force depend on RH. The adhesion force between a particle and a planar surface in atmospheric environments was modeled as the contribution of three major force components: capillary, van der Waals, and electrostatic interaction forces. Adhesion force measurements for Bt spore (silica particle) and the gold surface system were comparable with calculations. Modeling results show that there is a critical RH value, which depends on the hydrophobicity of the materials involved, below which the water meniscus does not form and the contribution of the capillary force is zero. As RH increases, the van der Waals force decreases while the capillary force increases to a maximum value.

  3. Germination of Spores of Astrobiologically Relevant Bacillus Species in High-Salinity Environments

    Science.gov (United States)

    Nagler, Katja; Julius, Christina; Moeller, Ralf

    2016-07-01

    In times of increasing space exploration and search for extraterrestrial life, new questions and challenges for planetary protection, aiming to avoid forward contamination of different planets or moons with terrestrial life, are emerging. Spore-forming bacteria such as Bacillus species have a high contamination potential due to their spores' extreme resistance, enabling them to withstand space conditions. Spores require liquid water for their conversion into a growing cell (i.e., spore germination and subsequent growth). If present, water on extraterrestrial planets or moons is likely to be closely associated with salts (e.g., in salty oceans or brines), thus constituting high-salinity environments. Spores of Bacillus subtilis can germinate despite very high salt concentrations, although salt stress does exert negative effects on this process. In this study, germination and metabolic reactivation ("outgrowth") of spores of five astrobiologically relevant Bacillus species (B. megaterium, B. pumilus SAFR-032, B. nealsonii, B. mojavensis, and B. vallismortis) in high salinity (≤3.6 M NaCl) were investigated. Spores of different species exhibited different germination and outgrowth capabilities in high salinity, which strongly depended on germination conditions, especially the exact composition of the medium. In this context, a new "universal" germination trigger for Bacillus spores, named KAGE (KCl, L-alanine, D-glucose, ectoine), was identified, which will be very useful for future comparative germination and outgrowth studies on different Bacillus species. Overall, this study yielded interesting new insights on salt stress effects on spore germination and points out the difficulty of predicting the potential of spores to contaminate salty environments on extraterrestrial celestial bodies.

  4. Bacterial spore survival after exposure to HZE particle bombardment -implication for the lithopanspermia hypothesis.

    Science.gov (United States)

    Moeller, Ralf; Berger, Thomas; Matthiä, Daniel; Okayasu, Ryuichi; Kitamura, H.; Reitz, Guenther

    transcriptional response during spore germination" (Moeller et al., 2008 [3]). To simulate the interplanetary journey of a meteorite, stacks of spore-samples on gabbro slides in different depths were exposed. Spore survival and the rate of the induced mutations (i.e., sporulation-deficiency (Spo-)) depended on the LET of the applied species of ions as well as on the location (and depth) of the irradiated spores in the artificial meteorite. The exposure to high LET iron ions led to a low level of spore survival and increased frequency of mutation to Spo-compared to low-energy charged particles compared to the low LET helium ions. In order to obtain insights on the role of DNA repair by nonhomologous end joining (NHEJ), homologous recombination (HR) and apurinic/apyrimidinic (AP) endonucleases in B. subtilis spore resistance to high-energy charged particles has been studied in parallel. Spores deficient in NHEJ and AP endonucleases were significantly more sensitive to HZE particle bombardment than were the HR-mutant and wild-type spores, indicating that NHEJ and AP endonucleases provide DNA break repair pathways during spore germination. ((References: [1] Arrhenius, S. 1903. Die Verbreitung des Lebens im Weltenraum. Umschau 7:481-485.; [2] Nicholson, W. L. 2009. Ancient micronauts: interplanetary transport of microbes by cosmic impacts. Trends Mi-crobiol. 17:243-250.; [3] Moeller, R., P. Setlow, G. Horneck, T. Berger, G. Reitz, P. Rettberg, A. J. Doherty, R. Okayasu, and W. L. Nicholson. 2008. Roles of the major, small, acid-soluble spore proteins and spore-specific and universal DNA repair mechanisms in resistance of Bacillus subtilis spores to ionizing radiation from X-rays and high-energy charged-particle bombardment. J. Bacteriol. 190:1134-1140.))

  5. What can spores do for us?

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, M.J. van der

    2003-01-01

    Many organisms have the ability to form spores, a remarkable phase in their life cycles. Compared with vegetative cells, spores have several advantages (e.g. resistance to toxic compounds, temperature, desiccation and radiation) making them well suited to various applications. The applications of sp

  6. What can spores do for us?

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, M.J. van der

    2003-01-01

    Many organisms have the ability to form spores, a remarkable phase in their life cycles. Compared with vegetative cells, spores have several advantages (e.g. resistance to toxic compounds, temperature, desiccation and radiation) making them well suited to various applications. The applications of

  7. What can spores do for us?

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, van der M.J.

    2003-01-01

    Many organisms have the ability to form spores, a remarkable phase in their life cycles. Compared with vegetative cells, spores have several advantages (e.g. resistance to toxic compounds, temperature, desiccation and radiation) making them well suited to various applications. The applications of sp

  8. Use of Yeast Spores for Microencapsulation of Enzymes

    OpenAIRE

    2014-01-01

    Here, we report a novel method to produce microencapsulated enzymes using Saccharomyces cerevisiae spores. In sporulating cells, soluble secreted proteins are transported to the spore wall. Previous work has shown that the spore wall is capable of retaining soluble proteins because its outer layers work as a diffusion barrier. Accordingly, a red fluorescent protein (RFP) fusion of the α-galactosidase, Mel1, expressed in spores was observed in the spore wall even after spores were subjected to...

  9. Architecture and Assembly of the Bacillus subtilis Spore Coat

    Science.gov (United States)

    2014-09-26

    icandy contaminated with germinated spores and these germinat ed spores were removed by centrifugation in a one step HistodenzTM (Sigma, St. Louis...spore resistance but also because some coat proteins play significant roles in spore germination . However, much recent work on the spore coat has... germinating spores of various Bacillus [14,21 30] and Clostridium [3 1] species. H owever, this analysis has generally been conducted on wild type

  10. Microwave inactivation of Bacillus atrophaeus spores in healthcare waste.

    Science.gov (United States)

    Oliveira, E A; Nogueira, N G P; Innocentini, M D M; Pisani, R

    2010-11-01

    Public healthcare wastes from the region of Ribeirão Preto, Brazil, pre-sterilized in an autoclave, were inoculated with spores of Bacillus atrophaeus for microwave processing on a laboratory scale. The influence of waste moisture (40%, 50% and 60% wet basis), presence of surfactant, power per unit mass of waste (100, 150 and 200 W/kg) and radiation exposure time (from 5 to 40 min) on the heating curves was investigated. The most favorable conditions for waste heating with respect to moisture and use of surfactant were then applied in an experimental analysis of the degree of inactivation of B. atrophaeus spores as a function of time and power per unit mass of waste. Based on Chick's and Arrhenius laws, the experimental results were adjusted by the least squares method to determine the activation energies (9203-5782 J/mol) and the Arrhenius pre-exponential factor (0.23 min(-1)). The kinetic parameters thus obtained enabled us to predict the degree of inactivation achieved for B. atrophaeus spores in typical healthcare waste. The activation energy was found to decrease as the power per waste mass increased, leading to the conclusion that, in addition to the thermal effect on the inactivation of B. atrophaeus spores, there was an effect inherent to radiation. Copyright © 2010 Elsevier Ltd. All rights reserved.

  11. Investigating the thermodynamic stability of Bacillus subtilis spore-uranium(VI) adsorption though surface complexation modeling

    Science.gov (United States)

    Harrold, Z.; Hertel, M.; Gorman-Lewis, D.

    2012-12-01

    Dissolved uranium speciation, mobility, and remediation are increasingly important topics given continued and potential uranium (U) release from mining operations and nuclear waste. Vegetative bacterial cell surfaces are known to adsorb uranium and may influence uranium speciation in the environment. Previous investigations regarding U(VI) adsorption to bacterial spores, a differentiated and dormant cell type with a tough proteinaceous coat, include U adsorption affinity and XAFS data. We investigated the thermodynamic stability of aerobic, pH dependent uranium adsorption to bacterial spore surfaces using purified Bacillus subtilis spores in solution with 5ppm uranium. Adsorption reversibility and kinetic experiments indicate that uranium does not precipitate over the duration of the experiments and equilibrium is reached within 20 minutes. Uranium-spore adsorption edges exhibited adsorption at all pH measured between 2 and 10. Maximum adsorption was achieved around pH 7 and decreased as pH increased above 7. We used surface complexation modeling (SCM) to quantify uranium adsorption based on balanced chemical equations and derive thermodynamic stability constants for discrete uranium-spore adsorption reactions. Site specific thermodynamic stability constants provide insight on interactions occurring between aqueous uranium species and spore surface ligands. The uranium adsorption data and SCM parameters described herein, also provide a basis for predicting the influence of bacterial spores on uranium speciation in natural systems and investigating their potential as biosorption agents in engineered systems.

  12. Kinetics of germination of individual spores of Geobacillus stearothermophilus as measured by raman spectroscopy and differential interference contrast microscopy.

    Directory of Open Access Journals (Sweden)

    Tingting Zhou

    Full Text Available Geobacillus stearothermophilus is a gram-positive, thermophilic bacterium, spores of which are very heat resistant. Raman spectroscopy and differential interference contrast microscopy were used to monitor the kinetics of germination of individual spores of G. stearothermophilus at different temperatures, and major conclusions from this work were as follows. 1 The CaDPA level of individual G. stearothermophilus spores was similar to that of Bacillus spores. However, the Raman spectra of protein amide bands suggested there are differences in protein structure in spores of G. stearothermophilus and Bacillus species. 2 During nutrient germination of G. stearothermophilus spores, CaDPA was released beginning after a lag time (T(lag between addition of nutrient germinants and initiation of CaDPA release. CaDPA release was complete at T(release, and DT(release (T(release - T(lag was 1-2 min. 3 Activation by heat or sodium nitrite was essential for efficient nutrient germination of G. stearothermophilus spores, primarily by decreasing T(lag values. 4 Values of T(lag and T(release were heterogeneous among individual spores, but DT(release values were relatively constant. 5 Temperature had major effects on nutrient germination of G. stearothermophilus spores, as at temperatures below 65°C, average T(lag values increased significantly. 6 G. stearothermophilus spore germination with exogenous CaDPA or dodecylamine was fastest at 65°C, with longer T(lag values at lower temperatures. 7 Decoating of G. stearothermophilus spores slowed nutrient germination slightly and CaDPA germination significantly, but increased dodecylamine germination markedly. These results indicate that the dynamics and heterogeneity of the germination of individual G. stearothermophilus spores are generally similar to that of Bacillus species.

  13. Airway inflammation among compost workers exposed to actinomycetes spores

    Directory of Open Access Journals (Sweden)

    Kari Kulvik Heldal

    2015-05-01

    Full Text Available Objectives. To study the associations between exposure to bioaerosols and work-related symptoms, lung function and biomarkers of airway inflammation in compost workers. Materials and method. Personal full-shift exposure measurements were performed on 47 workers employed at five windrow plants (n=20 and five reactor plants (n=27. Samples were analyzed for endotoxins, bacteria, fungal and actinomycetes spores. Health examinations were performed on workers and 37 controls before and after work on the day exposure was measured. The examinations included symptoms recorded by questionnaire, lung function by spirometry and nasal dimensions by acoustic rhinometry (AR. The pneumoproteins CC16, SP-D and SP-A were measured in a blood sample drawn at the end of the day. Results. The levels of endotoxins (median 3 EU/m[sup]3[/sup] , range 0–730 EU/m[sup]3[/sup] and actinomycetes spores (median 0.2 × 10[sup]6[/sup] spores/m[sup]3[/sup] , range 0–590 × 10[sup]6[/sup] spores/m[sup]3[/sup] were significantly higher in reactor plants compared to windrow plants. However, windrow composting workers reported more symptoms than reactor composting workers, probably due to use of respiratory protection. Exposure-response relationships between actinomycetes spores exposure and respiratory effects, found as cough and nose irritation during a shift, was significantly increased (OR 4.3, 95% CI 1.1–16, OR 6.1, 95% CI 1.5–25, respectively, p<0.05 among workers exposed to 0.02–0.3 × 10[sup]6[/sup] actinomycetes spores/m 3 , and FEV1/FVC% decreased cross shift (b=–3.2, SE=1.5%, p<0.01. Effects were weaker in the highest exposed group, but these workers used respiratory protection, frequently limiting their actual exposure. No relationships were found between exposure and pneumoprotein concentrations. Conclusions. The major agent in the aerosol generated at compost plants was actinomycetes spores which was associated with work related cough symptoms and work

  14. NanoSIMS analysis of Bacillus spores for forensics

    Energy Technology Data Exchange (ETDEWEB)

    Weber, P K; Davisson, M L; Velsko, S P

    2010-02-23

    The threat associated with the potential use of radiological, nuclear, chemical and biological materials in terrorist acts has resulted in new fields of forensic science requiring the application of state-of-the-science analytical techniques. Since the anthrax letter attacks in the United States in the fall of 2001, there has been increased interest in physical and chemical characterization of bacterial spores. While molecular methods are powerful tools for identifying genetic differences, other methods may be able to differentiate genetically identical samples based on physical and chemical properties, as well as provide complimentary information, such as methods of production and approximate date of production. Microanalysis has the potential to contribute significantly to microbial forensics. Bacillus spores are highly structured, consisting of a core, cortex, coat, and in some species, an exosporium. This structure provides a template for constraining elemental abundance differences at the nanometer scale. The primary controls on the distribution of major elements in spores are likely structural and physiological. For example, P and Ca are known to be abundant in the spore core because that is where P-rich nucleic acids and Cadipicolinic acid are located, respectively. Trace elements are known to bind to the spore coat but the controls on these elements are less well understood. Elemental distributions and abundances may be directly related to spore production, purification and stabilization methodologies, which are of particular interest for forensic investigation. To this end, we are developing a high-resolution secondary ion mass spectrometry method using a Cameca NanoSIMS 50 to study the distribution and abundance of trace elements in bacterial spores. In this presentation we will review and compare methods for preparing and analyzing samples, as well as review results on the distribution and abundance of elements in bacterial spores. We use NanoSIMS to

  15. The Use of Germinants to Potentiate the Sensitivity of Bacillus anthracis Spores to Peracetic Acid.

    Science.gov (United States)

    Celebi, Ozgur; Buyuk, Fatih; Pottage, Tom; Crook, Ant; Hawkey, Suzanna; Cooper, Callum; Bennett, Allan; Sahin, Mitat; Baillie, Leslie

    2016-01-01

    Elimination of Bacillus anthracis spores from the environment is a difficult and costly process due in part to the toxicity of current sporicidal agents. For this reason we investigated the ability of the spore germinants L-alanine (100 mM) and inosine (5 mM) to reduce the concentration of peracetic acid (PAA) required to inactivate B. anthracis spores. While L-alanine significantly enhanced (p = 0.0085) the bactericidal activity of 500 ppm PAA the same was not true for inosine suggesting some form of negative interaction. In contrast the germinant combination proved most effective at 100 ppm PAA (p = 0.0009). To determine if we could achieve similar results in soil we treated soil collected from the burial site of an anthrax infected animal which had been supplemented with spores of the Sterne strain of B. anthracis to increase the level of contamination to 10(4) spores/g. Treatment with germinants followed 1 h later by 5000 ppm PAA eliminated all of the spores. In contrast direct treatment of the animal burial site using this approach delivered using a back pack sprayer had no detectable effect on the level of B. anthracis contamination or on total culturable bacterial numbers over the course of the experiment. It did trigger a significant, but temporary, reduction (p < 0.0001) in the total spore count suggesting that germination had been triggered under real world conditions. In conclusion, we have shown that the application of germinants increase the sensitivity of bacterial spores to PAA. While the results of the single field trial were inconclusive, the study highlighted the potential of this approach and the challenges faced when attempting to perform real world studies on B. anthracis spores contaminated sites.

  16. The use of germinants to potentiate the sensitivity of Bacillus anthracis spores to peracetic acid

    Directory of Open Access Journals (Sweden)

    Ozgur eCelebi

    2016-01-01

    Full Text Available Elimination of Bacillus anthracis spores from the environment is a difficult and costly process due in part to the toxicity of current sporicidal agents. For this reason we investigated the ability of the spore germinants L-alanine (100 mM and inosine (5 mM to reduce the concentration of peracetic acid (PAA required to inactivate B.anthracis spores. While L-alanine significantly enhanced (p=0.0085 the bactericidal activity of 500 ppm PAA the same was not true for inosine suggesting some form of negative interaction. In contrast the germinant combination proved most effective at 100 ppm PAA (p=0.0009. To determine if we could achieve similar results in soil we treated soil collected from the burial site of an anthrax infected animal which had been supplemented with spores of the Sterne strain of B.anthracis to increase the level of contamination to 104 spores/g. Treatment with germinants followed one hour later by 5000 ppm PAA eliminated all of the spores. In contrast direct treatment of the animal burial site using this approach delivered using a back pack sprayer had no detectable effect on the level of B.anthracis contamination or on total culturable bacterial numbers over the course of the experiment. It did trigger a significant, but temporary, reduction (p<0.0001 in the total spore count suggesting that germination had been triggered under real world conditions. In conclusion, we have shown that the application of germinants increase the sensitivity of bacterial spores to PAA. While the results of the single field trial were inconclusive, the study highlighted the potential of this approach and the challenges faced when attempting to perform real world studies on B.anthracis spores contaminated sites.

  17. Improved proteomic analysis following trichloroacetic acid extraction of Bacillus anthracis spore proteins.

    Science.gov (United States)

    Deatherage Kaiser, Brooke L; Wunschel, David S; Sydor, Michael A; Warner, Marvin G; Wahl, Karen L; Hutchison, Janine R

    2015-11-01

    Proteomic analysis of bacterial samples provides valuable information about cellular responses and functions under different environmental pressures. Analysis of cellular proteins is dependent upon efficient extraction from bacterial samples, which can be challenging with increasing complexity and refractory characteristics. While no single method can recover 100% of the bacterial proteins, selected protocols can improve overall protein isolation, peptide recovery, or enrichment for certain classes of proteins. The method presented here is technically simple, does not require specialized equipment such as a mechanical disrupter, and is effective for protein extraction of the particularly challenging sample type of Bacillus anthracis Sterne spores. The ability of Trichloroacetic acid (TCA) extraction to isolate proteins from spores and enrich for spore-specific proteins was compared to the traditional mechanical disruption method of bead beating. TCA extraction improved the total average number of proteins identified within a sample as compared to bead beating (547 vs 495, respectively). Further, TCA extraction enriched for 270 spore proteins, including those typically identified by first isolating the spore coat and exosporium layers. Bead beating enriched for 156 spore proteins more typically identified from whole spore proteome analyses. The total average number of proteins identified was equal using TCA or bead beating for easily lysed samples, such as B. anthracis vegetative cells. As with all assays, supplemental methods such as implementation of an alternative preparation method may simplify sample preparation and provide additional insight to the protein biology of the organism being studied.

  18. Ectomycorrhizal fungal spore bank recovery after a severe forest fire: some like it hot.

    Science.gov (United States)

    Glassman, Sydney I; Levine, Carrie R; DiRocco, Angela M; Battles, John J; Bruns, Thomas D

    2016-05-01

    After severe wildfires, pine recovery depends on ectomycorrhizal (ECM) fungal spores surviving and serving as partners for regenerating forest trees. We took advantage of a large, severe natural forest fire that burned our long-term study plots to test the response of ECM fungi to fire. We sampled the ECM spore bank using pine seedling bioassays and high-throughput sequencing before and after the California Rim Fire. We found that ECM spore bank fungi survived the fire and dominated the colonization of in situ and bioassay seedlings, but there were specific fire adapted fungi such as Rhizopogon olivaceotinctus that increased in abundance after the fire. The frequency of ECM fungal species colonizing pre-fire bioassay seedlings, post-fire bioassay seedlings and in situ seedlings were strongly positively correlated. However, fire reduced the ECM spore bank richness by eliminating some of the rare species, and the density of the spore bank was reduced as evidenced by a larger number of soil samples that yielded uncolonized seedlings. Our results show that although there is a reduction in ECM inoculum, the ECM spore bank community largely remains intact, even after a high-intensity fire. We used advanced techniques for data quality control with Illumina and found consistent results among varying methods. Furthermore, simple greenhouse bioassays can be used to determine which fungi will colonize after fires. Similar to plant seed banks, a specific suite of ruderal, spore bank fungi take advantage of open niche space after fires.

  19. Fluorescence-based methods for the detection of pressure-induced spore germination and inactivation

    Science.gov (United States)

    Baier, Daniel; Reineke, Kai; Doehner, Isabel; Mathys, Alexander; Knorr, Dietrich

    2011-03-01

    The application of high pressure (HP) provides an opportunity for the non-thermal preservation of high-quality foods, whereas highly resistant bacterial endospores play an important role. It is known that the germination of spores can be initiated by the application of HP. Moreover, the resistance properties of spores are highly dependent on their physiological states, which are passed through during the germination. To distinguish between different physiological states and to detect the amount of germinated spores after HP treatments, two fluorescence-based methods were applied. A flow cytometric method using a double staining with SYTO 16 as an indicator for germination and propidium iodide as an indicator for membrane damage was used to detect different physiological states of the spores. During the first step of germination, the spore-specific dipicolinic acid (DPA) is released [P. Setlow, Spore germination, Curr. Opin. Microbiol. 6 (2003), pp. 550-556]. DPA reacts with added terbium to form a distinctive fluorescent complex. After measuring the fluorescence intensity at 270 nm excitation wavelength in a fluorescence spectrophotometer, the amount of germinated spores can be determined. Spores of Bacillus subtilis were treated at pressures from 150 to 600 MPa and temperatures from 37 °C to 60 °C in 0.05 M ACES buffer solution (pH 7) for dwell times of up to 2 h. During the HP treatments, inactivation up to 2log 10 cycles and thermal sensitive populations up to 4log 10 cycles could be detected by plate counts. With an increasing number of thermal sensitive spores, an increased proportion of spores in germinated states was detected by flow cytometry. Also the released amount of DPA increased during the dwell times. Moreover, a clear pressure-temperature-time-dependency was shown by screening different conditions. The fluorescence-based measurement of the released DPA can provide the opportunity of an online monitoring of the germination of spores under HP inside

  20. Nanomechanical analysis of Clostridium tyrobutyricum spores.

    Science.gov (United States)

    Andreeva, N; Bassi, D; Cappa, F; Cocconcelli, P S; Parmigiani, F; Ferrini, G

    2010-12-01

    In this work we report on the measurement of the Young modulus of the external surface of Clostridium tyrobutyricum spores in air with an atomic force microscope. The Young modulus can be reliably measured despite the strong tip-spore adhesion forces and the need to immobilize the spores due to their slipping on most substrates. Moreover, we investigate the disturbing factors and consider some practical aspects that influence the measurements of elastic properties of biological objects with the atomic force microscopy indentation techniques.

  1. A Clostridium difficile-Specific, Gel-Forming Protein Required for Optimal Spore Germination

    Directory of Open Access Journals (Sweden)

    M. Lauren Donnelly

    2017-01-01

    Full Text Available Clostridium difficile is a Gram-positive spore-forming obligate anaerobe that is a leading cause of antibiotic-associated diarrhea worldwide. In order for C. difficile to initiate infection, its aerotolerant spore form must germinate in the gut of mammalian hosts. While almost all spore-forming organisms use transmembrane germinant receptors to trigger germination, C. difficile uses the pseudoprotease CspC to sense bile salt germinants. CspC activates the related subtilisin-like protease CspB, which then proteolytically activates the cortex hydrolase SleC. Activated SleC degrades the protective spore cortex layer, a step that is essential for germination to proceed. Since CspC incorporation into spores also depends on CspA, a related pseudoprotease domain, Csp family proteins play a critical role in germination. However, how Csps are incorporated into spores remains unknown. In this study, we demonstrate that incorporation of the CspC, CspB, and CspA germination regulators into spores depends on CD0311 (renamed GerG, a previously uncharacterized hypothetical protein. The reduced levels of Csps in gerG spores correlate with reduced responsiveness to bile salt germinants and increased germination heterogeneity in single-spore germination assays. Interestingly, asparagine-rich repeat sequences in GerG’s central region facilitate spontaneous gel formation in vitro even though they are dispensable for GerG-mediated control of germination. Since GerG is found exclusively in C. difficile, our results suggest that exploiting GerG function could represent a promising avenue for developing C. difficile-specific anti-infective therapies.

  2. A Clostridium difficile-Specific, Gel-Forming Protein Required for Optimal Spore Germination

    Science.gov (United States)

    Donnelly, M. Lauren; Li, William; Li, Yong-qing; Hinkel, Lauren; Setlow, Peter

    2017-01-01

    ABSTRACT Clostridium difficile is a Gram-positive spore-forming obligate anaerobe that is a leading cause of antibiotic-associated diarrhea worldwide. In order for C. difficile to initiate infection, its aerotolerant spore form must germinate in the gut of mammalian hosts. While almost all spore-forming organisms use transmembrane germinant receptors to trigger germination, C. difficile uses the pseudoprotease CspC to sense bile salt germinants. CspC activates the related subtilisin-like protease CspB, which then proteolytically activates the cortex hydrolase SleC. Activated SleC degrades the protective spore cortex layer, a step that is essential for germination to proceed. Since CspC incorporation into spores also depends on CspA, a related pseudoprotease domain, Csp family proteins play a critical role in germination. However, how Csps are incorporated into spores remains unknown. In this study, we demonstrate that incorporation of the CspC, CspB, and CspA germination regulators into spores depends on CD0311 (renamed GerG), a previously uncharacterized hypothetical protein. The reduced levels of Csps in gerG spores correlate with reduced responsiveness to bile salt germinants and increased germination heterogeneity in single-spore germination assays. Interestingly, asparagine-rich repeat sequences in GerG’s central region facilitate spontaneous gel formation in vitro even though they are dispensable for GerG-mediated control of germination. Since GerG is found exclusively in C. difficile, our results suggest that exploiting GerG function could represent a promising avenue for developing C. difficile-specific anti-infective therapies. PMID:28096487

  3. Quantitative immunofluorescence studies of the serology of Bacillus anthracis spores.

    OpenAIRE

    1983-01-01

    A fluorescein-conjugated antibody against formalin-inactivated spores of Bacillus anthracis Vollum reacted only weakly with a variety of Bacillus species in microfluorometric immunofluorescence assays. A conjugated antibody against spores of B. anthracis Sterne showed little affinity for spores of several B. anthracis isolates including B. anthracis Vollum, indicating that more than one anthrax spore serotype exists.

  4. Incidence, diversity and characteristics of spores of psychrotolerant spore formers in various REPFEDS produced in Belgium.

    Science.gov (United States)

    Samapundo, S; Devlieghere, F; Xhaferi, R; Heyndrickx, M

    2014-12-01

    The major objectives of this study were to determine the incidence of psychrotolerant spore formers from REPFEDS marketed in Belgium, and their diversity and characteristics. Spore formers in general were found as spores on 38.3% of the food samples and in 85% food products types evaluated. 76% of the food samples containing spore formers had spores before enrichment. A total of 86 spore formers were isolated from the samples. 28 of 86 bacterial spore formers (32.6%) were capable of vegetative growth at 7 °C. 96% (27/28) of these psychrotolerant spore formers were determined to belong to Bacillus or related genera. According to a (GTG)5-PCR analysis, 24 of these 28 isolates were genetically distinct from each other. 10.7% (3/28) of the bacilli were determined to belong to the Bacillus cereus group, namely B. cereus (chicken curry and Edam cheese) and Bacillus mycoides (Emmental cheese). Almost half of the bacilli (12/27) were putatively identified as Bacillus pumilus, which occurs ubiquitously in nature and has been associated with outbreaks of foodborne disease. Only one psychrotolerant clostridium, Clostridium tyrobutyricum, was isolated in the study. The results of this study show the highly diverse ecology and spoilage potential of psychrotolerant spore formers in REPFEDs marketed in Belgium.

  5. Measurements of DNA Damage and Repair in Bacillus anthracis Sterne Spores by UV Radiation

    Science.gov (United States)

    2014-09-18

    increase of water, protein motility begins and enzymatic activity is initiated. The outgrowth period of germination is the only step that contains...process [23]. 17 Figure 5. The spore germination process. Germination occurs in 2 main stages. The initiation/activation step involves the...with a red fluorescent protein was transformed into Ba Sterne cells prior. Following irradiation, germination media was added and the spores were

  6. Rapid onsite assessment of spore viability.

    Energy Technology Data Exchange (ETDEWEB)

    Branda, Steven; Lane, Todd W.; VanderNoot, Victoria A.; Gaucher, Sara P.; Jokerst, Amanda S.

    2005-12-01

    This one year LDRD addresses problems of threat assessment and restoration of facilities following a bioterror incident like the incident that closed down mail facilities in late 2001. Facilities that are contaminated with pathogenic spores such as B. anthracis spores must be shut down while they are treated with a sporicidal agent and the effectiveness of the treatment is ascertained. This process involves measuring the viability of spore test strips, laid out in a grid throughout the facility; the CDC accepted methodologies require transporting the samples to a laboratory and carrying out a 48 hr outgrowth experiment. We proposed developing a technique that will ultimately lead to a fieldable microfluidic device that can rapidly assess (ideally less than 30 min) spore viability and effectiveness of sporicidal treatment, returning facilities to use in hours not days. The proposed method will determine viability of spores by detecting early protein synthesis after chemical germination. During this year, we established the feasibility of this approach and gathered preliminary results that should fuel a future more comprehensive effort. Such a proposal is currently under review with the NIH. Proteomic signatures of Bacillus spores and vegetative cells were assessed by both slab gel electrophoresis as well as microchip based gel electrophoresis employing sensitive laser-induced fluorescence detection. The conditions for germination using a number of chemical germinants were evaluated and optimized and the time course of protein synthesis was ascertained. Microseparations were carried out using both viable spores and spores inactivated by two different methods. A select number of the early synthesis proteins were digested into peptides for analysis by mass spectrometry.

  7. Fungal spores as potential ice nuclei in fog/cloud water and snow

    Science.gov (United States)

    Bauer, Heidi; Goncalves, Fabio L. T.; Schueller, Elisabeth; Puxbaum, Hans

    2010-05-01

    INTRODUCTION: In discussions about climate change and precipitation frequency biological ice nucleation has become an issue. While bacterial ice nucleation (IN) is already well characterized and even utilized in industrial processes such as the production of artificial snow or to improve freezing processes in food industry, less is known about the IN potential of fungal spores which are also ubiquitous in the atmosphere. A recent study performed at a mountain top in the Rocky Mountains suggests that fungal spores and/or pollen might play a role in increased IN abundance during periods of cloud cover (Bowers et al. 2009). In the present work concentrations of fungal spores in fog/cloud water and snow were determined. EXPERIMENTAL: Fog samples were taken with an active fog sampler in 2008 in a traffic dominated area and in a national park in São Paulo, Brazil. The number concentrations of fungal spores were determined by microscopic by direct enumeration by epifluorescence microscopy after staining with SYBR Gold nucleic acid gel stain (Bauer et al. 2008). RESULTS: In the fog water collected in the polluted area at a junction of two highly frequented highways around 22,000 fungal spores mL-1 were counted. Fog in the national park contained 35,000 spores mL-1. These results were compared with cloud water and snow samples from Mt. Rax, situated at the eastern rim of the Austrian Alps. Clouds contained on average 5,900 fungal spores mL-1 cloud water (1,300 - 11,000) or 2,200 spores m-3 (304 - 5,000). In freshly fallen snow spore concentrations were lower than in cloud water, around 1,000 fungal spores mL-1 were counted (Bauer et al. 2002). In both sets of samples representatives of the ice nucleating genus Fusarium could be observed. REFERENCES: Bauer, H., Kasper-Giebl, A., Löflund, M., Giebl, H., Hitzenberger, R., Zibuschka, F., Puxbaum, H. (2002). The contribution of bacteria and fungal spores to the organic carbon content of cloud water, precipitation and aerosols

  8. Structural Analysis of Bacillus subtilis Spore Peptidoglycan During Sporulation

    OpenAIRE

    2000-01-01

    Structural analysis of Bacillus subtilis spore peptidoglycan during sporulation:Jennifer L. Meador-Parton:David L. Popham, Chairman:Department of Biology:(ABSTRACT):Bacterial spore peptidoglycan (PG) is very loosely cross-linked relative to vegetative PG. Theories suggest that loosely cross-linked spore PG may have a flexibility which contributes to the attainment of spore core dehydration. The structure of the PG found in fully dormant spores has previously been examined in wild type and m...

  9. Nanomechanical Characterization of Bacillus anthracis Spores by Atomic Force Microscopy

    OpenAIRE

    2016-01-01

    The study of structures and properties of bacterial spores is important to understanding spore formation and biological responses to environmental stresses. While significant progress has been made over the years in elucidating the multilayer architecture of spores, the mechanical properties of the spore interior are not known. Here, we present a thermal atomic force microscopy (AFM) study of the nanomechanical properties of internal structures of Bacillus anthracis spores. We developed a nan...

  10. The Role of Aquaporins in pH-Dependent Germination of Rhizopus delemar Spores.

    Science.gov (United States)

    Turgeman, Tidhar; Shatil-Cohen, Arava; Moshelion, Menachem; Teper-Bamnolker, Paula; Skory, Christopher D; Lichter, Amnon; Eshel, Dani

    2016-01-01

    Rhizopus delemar and associated species attack a wide range of fruit and vegetables after harvest. Host nutrients and acidic pH are required for optimal germination of R. delemar, and we studied how this process is triggered. Glucose induced spore swelling in an acidic environment, expressed by an up to 3-fold increase in spore diameter, whereas spore diameter was smaller in a neutral environment. When suspended in an acidic environment, the spores started to float, indicating a change in their density. Treatment of the spores with HgCl2, an aquaporin blocker, prevented floating and inhibited spore swelling and germ-tube emergence, indicating the importance of water uptake at the early stages of germination. Two putative candidate aquaporin-encoding genes-RdAQP1 and RdAQP2-were identified in the R. delemar genome. Both presented the conserved NPA motif and six-transmembrane domain topology. Expressing RdAQP1 and RdAQP2 in Arabidopsis protoplasts increased the cells' osmotic water permeability coefficient (Pf) compared to controls, indicating their role as water channels. A decrease in R. delemar aquaporin activity with increasing external pH suggested pH regulation of these proteins. Substitution of two histidine (His) residues, positioned on two loops facing the outer side of the cell, with alanine eliminated the pH sensing resulting in similar Pf values under acidic and basic conditions. Since hydration is critical for spore switching from the resting to activate state, we suggest that pH regulation of the aquaporins can regulate the initial phase of R. delemar spore germination, followed by germ-tube elongation and host-tissue infection.

  11. Graphical procedure for comparing thermal death of Bacillus stearothermophilus spores in saturated and superheated steam.

    Science.gov (United States)

    SHULL, J J; ERNST, R R

    1962-09-01

    The thermal death curve of dried spores of Bacillus stearothermophilus in saturated steam was characterized by three phases: (i) a sharp initial rise in viable count; (ii) a low rate of death which gradually increased; and (iii) logarithmic death at maximal rate. The first phase was a reflection of inadequate heat activation of the spore population. The second and third phases represented the characteristic thermal death curve of the spores in saturated steam. A jacketed steam sterilizer, equipped with a system for initial evacuation of the chamber, was examined for superheat during normal operation. Measurements of spore inactivation and temperature revealed superheat in surface layers of fabrics being processed in steam at 121 C. The high temperature of the fabric surfaces was attributed to absorption of excess heat energy from superheated steam. The superheated steam was produced at the beginning of the normal sterilizing cycle by transfer of heat from the steam-heated jacket to saturated steam entering the vessel.

  12. Effect of linear alkyl benzene sulfonate on germination of spores of the aquatic fern Ceratopteris thalictroides

    Energy Technology Data Exchange (ETDEWEB)

    Singh, J.; Devi, S. (National Botanical Research Institute, Lucknow (India))

    1989-07-01

    Validity of fern spore germination bioassays for the effects of environmental pollution was established by many researchers. Some workers studied the phytotoxicity of linear alkyl benzene sulfonate (LAS) on the spores of Diplazium esculentum and observed that LAS levels above 0.001% are toxic to fern spores. Water pollution due to synthetic detergents has been increasing continuously during the last few years due to their extensive use in domestic life, agriculture and industry. These detergents are among the most common pollutants responsible for water pollution. In view of this fact, the phytotoxicity of LAS on germination of an aquatic fern Ceratopteris thalictroides spores was studied. However, in these studies, only germination pattern was taken as index and no observations were made on the developmental stages.

  13. Dynamics of cap opening in Agaricus bisporus and changes in spore numbers vs. cap opening and radiation treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, E.; Voeroes, Zs.; Farkas, J. (Koezponti Elelmiszeripari Kutato Intezet, Budapest (Hungary))

    1981-01-01

    The spore count in Agaricus bisporus treated with radiation doses of 1.5 and 2.5 kGy was studied as a function of cap opening and radiation treatment (at 14-16 deg C and RH 80-90%). It was established that spore formation starts in the mushroom while the cap is still closed and the opening of the pileus starts when the spore number begins to increase. In treated mushrooms not only the cap remains closed but in lack of the development of gills the development of spores is also inhibited. Maturation retardation becomes apparent in the inhibition of the increase in number and of the darkening of the spores.

  14. Survival of B. Horneckiae Spores Under Ground-simulated Space Conditions

    Science.gov (United States)

    Schanche, Bradley

    2012-01-01

    To prevent forward contamination and maintain the scientific integrity of future life detection missions, it is important to characterize and attempt to eliminate terrestrial microorganisms associated with exploratory spacecraft and landing vehicles. Among the organisms isolated from spacecraft-associated habitats, spore-forming microbes are highly resistant to various physical and chemical conditions, which include ionizing and UV radiation, desiccation and oxidative stress, and the harsh environment of outer space or planetary surfaces. Recently a radiation resistant, spore forming bacterial isolate, Bacillus horneckiae, was isolated from a clean room of the Kennedy Space Center where the Phoenix spacecraft was assembled. The exceptionally high tolerance of extreme conditions demonstrated by sporeforming bacteria highlighted the need to assess the viability of these microbes in situ (in real) space. The proposed BOSS (Biofilm Organisms Surfing Space) project aims to understand the mechanisms by which biofilm forming organisms, such as B. horneckiae, will potentially be able to withstand harsh space conditions. As previously stated, the spore producing ability of these species gives them increased survivability to harsh conditions. Some of the spores will have the protective exosporium layer artificially removed before the test to determine if the existence of this layer significantly changes the survivability during the mission. In preparation for that experiment, we analyzed spores which were exposed during a ground simulation, the EXPOSE R2 Biofilm Organisms Surfing Space (BOSS). Previous to exposure, spores were deposited onto spacecraft grade aluminum coupons in a spore suspension calculated to contain between 10(exp 7) and 10(exp 8) spores. This precursor series will be used to establish a baseline survivability function for comparison with the future flight tests during EXPOSE-R. For each coupon, a 10% polyvinyl alcohol (PVA) film was applied and peeled

  15. Effects of Electrolyzed Oxidizing Water on Inactivation of Bacillus subtilis and Bacillus cereus Spores in Suspension and on Carriers.

    Science.gov (United States)

    Zhang, Chunling; Li, Baoming; Jadeja, Ravirajsinh; Hung, Yen-Con

    2016-01-01

    Spores of some Bacillus species are responsible for food spoilage and foodborne disease. These spores are highly resistant to various interventions and cooking processes. In this study, the sporicidal efficacy of acidic electrolyzed oxidizing (EO) water (AEW) and slightly acidic EO water (SAEW) with available chlorine concentration (ACC) of 40, 60, 80, 100, and 120 mg/L and treatment time for 1, 2, 3, 4, 5, and 6 min were tested on Bacillus subtilis and Bacillus cereus spores in suspension and on carrier with or without organics. The reduction of spore significantly increased with increasing ACC and treatment time (P waters containing 120 mg/L ACC, while only SAEW at 120 mg/L and 2 min treatment achieved >6 log reductions of B. subtilis spore. Both types of EO water with ACC of 60 mg/L and 6 min treatment achieved a reduction of B. subtilis and B. cereus spores to nondetectable level. EO water with ACC of 80 mg/L and treatment time of 3 min on carrier test without organics addition resulted in reductions of B. subtilis spore to nondetectable level. But, addition of 0.3% organics on carrier decreased the inactivation effect of EO water. This study indicated that EO water was highly effective in inactivation of B. subtilis and B. cereus spores in suspension or on carrier, and therefore, rendered it as a promising disinfectant to be applied in food industry.

  16. Spores of Aspergillus versicolor isolated from indoor air of a moisture-damaged building provoke acute inflammation in mouse lungs.

    Science.gov (United States)

    Jussila, Juha; Komulainen, Hannu; Kosma, Veli-Matti; Nevalainen, Aino; Pelkonen, Jukka; Hirvonen, Maija-Riitta

    2002-12-01

    Microbial growth in moisture-damaged buildings has been associated with respiratory health effects, and the spores of the mycotoxin producing fungus Aspergillus versicolor are frequently present in the indoor air. To characterize the potential of these spores to cause harmful respiratory effects, mice were exposed via intratracheal instillation to a single dose of the spores of A. versicolor (1 x 10(5), 1 x 10(6), 5 x 10(6), 1 x 10(7), or 1 x 10(8) spores), isolated from the indoor air of a moisture-damaged building. Inflammation and toxicity in lungs were evaluated 24 h later by assessment of biochemical markers and histopathology. The time course of the effects was investigated with the dose of 5 x 10(6) spores for up to 28 days. The exposure to the spores increased transiently proinflammatory cytokine levels (tumor necrosis factor [TNF] alpha and interleukin [IL]-6) in bronchoalveolar lavage fluid (BALF). The cytokine responses were dose and time dependent. The highest cytokine concentrations were measured at 6 h after the dose, and they returned to the control level by 3 days. Moreover, the spores of A. versicolor recruited inflammatory cells into airways: Neutrophils peaked transiently at 24 h, macrophages at 3 days, and lymphocytes at 7 days after the dosing. The inflammatory cell response did not completely disappear during the subsequent 28 days, though no histopathological changes were seen at that time point. The spores did not induce expression of inducible nitric oxide synthase in lavaged cells. Only the highest spore dose (1 x 10(8)) markedly increased serum IL-6, increased vascular leakage, and caused cytotoxicity (i.e., increased levels of albumin, total protein, lactate dehydrogenase [LDH], and hemoglobin in BALF) in the airways. In summary, the spores of A. versicolor caused acute inflammation in mouse lungs. This indicates that they have potential to provoke adverse health effects in the occupants of moisture-damaged buildings.

  17. Bacillus cereus spore damage recovery and diversity in spore germination and carbohydrate utilisation

    NARCIS (Netherlands)

    Warda, Alicja K.

    2016-01-01

    Bacterial spores are extremely robust survival vehicles that are highly resistant towards environmental stress conditions including heat, UV radiation and other stresses commonly applied during food production and preservation. Spores, including those of the toxin-producing food-borne human pathogen

  18. Sensitive, Rapid Detection of Bacterial Spores

    Science.gov (United States)

    Kern, Roger G.; Venkateswaran, Kasthuri; Chen, Fei; Pickett, Molly; Matsuyama, Asahi

    2009-01-01

    A method of sensitive detection of bacterial spores within delays of no more than a few hours has been developed to provide an alternative to a prior three-day NASA standard culture-based assay. A capability for relatively rapid detection of bacterial spores would be beneficial for many endeavors, a few examples being agriculture, medicine, public health, defense against biowarfare, water supply, sanitation, hygiene, and the food-packaging and medical-equipment industries. The method involves the use of a commercial rapid microbial detection system (RMDS) that utilizes a combination of membrane filtration, adenosine triphosphate (ATP) bioluminescence chemistry, and analysis of luminescence images detected by a charge-coupled-device camera. This RMDS has been demonstrated to be highly sensitive in enumerating microbes (it can detect as little as one colony-forming unit per sample) and has been found to yield data in excellent correlation with those of culture-based methods. What makes the present method necessary is that the specific RMDS and the original protocols for its use are not designed for discriminating between bacterial spores and other microbes. In this method, a heat-shock procedure is added prior to an incubation procedure that is specified in the original RMDS protocols. In this heat-shock procedure (which was also described in a prior NASA Tech Briefs article on enumerating sporeforming bacteria), a sample is exposed to a temperature of 80 C for 15 minutes. Spores can survive the heat shock, but nonspore- forming bacteria and spore-forming bacteria that are not in spore form cannot survive. Therefore, any colonies that grow during incubation after the heat shock are deemed to have originated as spores.

  19. Ultrastructure of spore development in Scutellospora heterogama.

    Science.gov (United States)

    Jeffries, Peter; Robinson-Boyer, Louisa; Rice, Paul; Newsam, Ray J; Dodd, John C

    2007-07-01

    The ultrastructural detail of spore development in Scutellospora heterogama is described. Although the main ontogenetic events are similar to those described from light microscopy, the complexity of wall layering is greater when examined at an ultrastructural level. The basic concept of a rigid spore wall enclosing two inner, flexible walls still holds true, but there are additional zones within these three walls distinguishable using electron microscopy, including an inner layer that is involved in the formation of the germination shield. The spore wall has three layers rather than the two reported previously. An outer, thin ornamented layer and an inner, thicker layer are both derived from the hyphal wall and present at all stages of development. These layers differentiate into the outer spore layer visible at the light microscope level. A third inner layer unique to the spore develops during spore swelling and rapidly expands before contracting back to form the second wall layer visible by light microscopy. The two inner flexible walls also are more complex than light microscopy suggests. The close association with the inner flexible walls with germination shield formation consolidates the preferred use of the term 'germinal walls' for these structures. A thin electron-dense layer separates the two germinal walls and is the region in which the germination shield forms. The inner germinal wall develops at least two sub-layers, one of which has an appearance similar to that of the expanding layer of the outer spore wall. An electron-dense layer is formed on the inner surface of the inner germinal wall as the germination shield develops, and this forms the wall surrounding the germination shield as well as the germination tube. At maturity, the outer germinal wall develops a thin, striate layer within its substructure.

  20. Spore test parameters matter: Mesophilic and thermophilic spore counts detected in raw milk and dairy powders differ significantly by test method.

    Science.gov (United States)

    Kent, D J; Chauhan, K; Boor, K J; Wiedmann, M; Martin, N H

    2016-07-01

    United States dairy industry exports have steadily risen in importance over the last 10yr, with dairy powders playing a particularly critical role. Currently, approximately half of US-produced nonfat dry milk and skim milk powder is exported. Reaching new and expanding existing export markets relies in part on the control of endospore-forming bacteria in dairy powders. This study reports baseline mesophilic and thermophilic spore counts and spore populations from 55 raw material samples (primarily raw milk) and 33 dairy powder samples from dairy powder processors across the United States. Samples were evaluated using various spore testing methodologies and included initial heat treatments of (1) 80°C for 12 min; (2) 100°C for 30 min; and (3) 106°C for 30 min. Results indicate that significant differences in both the level and population of spores were found for both raw milk and dairy powders with the various testing methods. Additionally, on average, spore counts were not found to increase significantly from the beginning to the end of dairy powder processing, most likely related to the absence of biofilm formation by processing plant-associated sporeformers (e.g., Anoxybacillus sp.) in the facilities sampled. Finally, in agreement with other studies, Bacillus licheniformis was found to be the most prevalent sporeformer in both raw materials and dairy powders, highlighting the importance of this organism in developing strategies for control and reduction of spore counts in dairy powders. Overall, this study emphasizes the need for standardization of spore enumeration methodologies in the dairy powder industry.

  1. Modelling the heat stress and the recovery of bacterial spores.

    Science.gov (United States)

    Mafart, P; Leguérinel, I

    1997-07-22

    After heat treatment, the temperature incubation and the medium composition, (pH and sodium chloride content) influence the capacity of injured spores to repair heat damage. The concept of heat resistance D- (decimal reduction time) and z-values (temperature increase which results in a ten fold reduction of the D value) is not sufficient and the ratio of spore recovery after incubation should be considered in calculations used in thermal processing of food. This paper aims to derive a model describing the recovery of injured spores as a function of both the heat treatment intensity and the environmental conditions. According to data from numerous investigators, when spores are incubated in unfavorable conditions, the ratio of cell recovery and the apparent D-value are reduced. Moreover the ratio of the apparent D-value and the estimated in optimal incubation D-value is constant and independent of the heat treatment conditions. Beyond these observations it is shown that the ratio of cell recovery with respect to the heat treatment F-value (exposure time, in minutes, at 121.1 degrees C which results in the same destruction ratio that the considered heat treatment does) is linear and can be quantified by using two factors independent of the heat treatment: the gamma-factor reflects the degree of precariousness due to the heat stress while the epsilon-factor reflects more intrinsically the incubation conditions without previous heat treatment. The gamma-factor varies as a function of the incubation temperature according to an Arrhenius law.

  2. Muricholic acids inhibit Clostridium difficile spore germination and growth.

    Directory of Open Access Journals (Sweden)

    Michael B Francis

    Full Text Available Infections caused by Clostridium difficile have increased steadily over the past several years. While studies on C. difficile virulence and physiology have been hindered, in the past, by lack of genetic approaches and suitable animal models, newly developed technologies and animal models allow these processes to be studied in detail. One such advance is the generation of a mouse-model of C. difficile infection. The development of this system is a major step forward in analyzing the genetic requirements for colonization and infection. While important, it is equally as important in understanding what differences exist between mice and humans. One of these differences is the natural bile acid composition. Bile acid-mediated spore germination is an important step in C. difficile colonization. Mice produce several different bile acids that are not found in humans. These muricholic acids have the potential to impact C. difficile spore germination. Here we find that the three muricholic acids (α-muricholic acid, β-muricholic acid and ω-muricholic acid inhibit C. difficile spore germination and can impact the growth of vegetative cells. These results highlight an important difference between humans and mice and may have an impact on C. difficile virulence in the mouse-model of C. difficile infection.

  3. Investigation of bacterial spore structure by high resolution solid-state nuclear magnetic resonance spectroscopy and transmission electron microscopy.

    Science.gov (United States)

    Leuschner, R G; Lillford, P J

    2001-01-22

    High resolution solid-state nuclear magnetic resonance spectroscopy (NMR) in combination with transmission electron microscopy (TEM) of spores of Bacillus cereus, an outer coatless mutant B. subtilis 322, an inner coatless mutant B. subtilis 325 and of germinated spores of B. subtilis CMCC 604 were carried out. Structural differences in the coats, mainly protein of spores were reflected by NMR spectra which indicated also differences in molecular mobility of carbohydrates which was partially attributed to the cortex. Dipicolinic acid (DPA) of spores of B. cereus displayed a high degree of solid state order and may be crystalline. Heat activation was studied on spores of B. subtilis 357 lux + and revealed a structural change when analysed by TEM but this was not associated with increases in molecular mobility since no effects were measured by NMR.

  4. [Concentration of allergic fungi spores in the air of flats in Lódź].

    Science.gov (United States)

    Krawczyk, P; Kowalski, M L; Ochecka-Szymańska, A

    1999-01-01

    The real contribution of moulds to the pathogenesis of allergic diseases remains unknown, although positive skin prick tests and/or specific serum IgE to moki allergens can be detected in 1-5% of atopic patients. A significant problem in assesment of exposure to mould allergens, resulting with difficulty in standarization of methods. The aim of this work was to assess the concentration of spores of 8 mould species in flats inhabited by peoples who Bont show any symptoms of allergy. The Open Petri Dish (OPD) method involving sedimentation of participles contained in the column of air over the dish was used to assess the number of spores in 1 m3 of indoor atmospheres. All colonies were counted, but only 8 mould species implicated in inhaled allergy were identified, ie.: Alternaria tenuis, Cladosporium herbarum, Helminthosporum halodes, Pullularia pullulans, Penicillium notatam, Rhizopus nigricans, Mucor mucedo, Aspergillus fumigatus. The tests were carried out in 10 flats located in various quarters of the cify of Lodź during three consecutive days of September 1995 between 5:00 pm and 6:04 pm. In analyzing the percentage of spores of each of the eight mould species tested we determined that, independent of fiat and test day, C. herbarum predominated. It is good agreement with the observations of other authors who report that among large quantities of fungi that are detected in late summer, usually C. herbarum spores dominate. This is the season when the incidence of the Cladosporium spores in the atmospheric air increases. Spores of H. halodes were detected least frequently. Our study demonstrated the presence of substantial amounts of mould spores in indoor air of houses in Lódź. The spores belong to species with documented allergenicity, suggesting that they may play a role in development of allergic sensitization in susceptible subjects.

  5. Dothistroma septosporum: spore production and weather conditions

    Energy Technology Data Exchange (ETDEWEB)

    Dvorak, M.; Drapela, K.; Kankovsky, L.

    2012-11-01

    Dartmouth's septosporum, the causal agent of Dothistroma needle blight is a widespread fungus which infects more than 80 species of coniferous trees through the entire world. Spreading of the infection is strongly affected by climatic factors of each locality where it is recorded. We attempt to describe the concrete limiting climatic factors necessary for the releasing of conidia of D. septosporum and to find out the timing of its spore production within the year. For this purpose we used an automatic volumetric spore trap and an automatic meteorological station. We found that a minimum daily average temperature of 10 degree centigrade was necessary for any spore production, as well as a long period of high air humidity. The values obtained in the present study were a little bit higher than those previously published, which may arise questions about a possible changing trend of the behaviour in the development of the Dothistroma needle blight causal agent. We used autoregressive integrated moving average (ARIMA) models to predict the spore counts on the base of previous values of spore counts and dew point. For a locality from Hackerovka, the best ARIMA model was 1,0,0; and for a locality from Lanzhot, the best was 3,1,0. (Author) 19 refs.

  6. Spore analysis and tetrad dissection of Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Ekwall, Karl; Thon, Genevieve

    2017-01-01

    Here we describe the processing of Schizosaccharomyces pombe spores in batches (random spore analysis) or through tetrad dissections. Spores are usually prepared from matings between haploid strains (producing zygotic asci) or from sporulating diploids (producing azygotic asci). In random spore...... analysis, a snail enzyme preparation is used to digest the walls of asci to release free spores that are diluted and plated to form colonies. In tetrad dissection, a needle attached to a micromanipulator is used to pick asci and separate spores. Tetrad dissection has traditionally been the method of choice...

  7. Identification of CdnL, a Putative Transcriptional Regulator Involved in Repair and Outgrowth of Heat-Damaged Bacillus cereus Spores.

    Directory of Open Access Journals (Sweden)

    Alicja K Warda

    Full Text Available Spores are widely present in the environment and are common contaminants in the food chain, creating a challenge for food industry. Nowadays, heat treatments conventionally applied in food processing may become milder to comply with consumer desire for products with higher sensory and nutritional values. Consequently subpopulations of spores may emerge that are sublethally damaged rather than inactivated. Such spores may germinate, repair damage, and eventually grow out leading to uncontrolled spoilage and safety issues. To gain insight into both the behaviour of damaged Bacillus cereus spores, and the process of damage repair, we assessed the germination and outgrowth performance using OD595 measurements and microscopy combined with genome-wide transcription analysis of untreated and heat-treated spores. The first two methods showed delayed germination and outgrowth of heat-damaged B. cereus ATCC14579 spores. A subset of genes uniquely expressed in heat-treated spores was identified with putative roles in the outgrowth of damaged spores, including cdnL (BC4714 encoding the putative transcriptional regulator CdnL. Next, a B. cereus ATCC14579 cdnL (BC4714 deletion mutant was constructed and assessment of outgrowth from heat-treated spores under food relevant conditions showed increased damage compared to wild type spores. The approach used in this study allows for identification of candidate genes involved in spore damage repair. Further identification of cellular parameters and characterisation of the molecular processes contributing to spore damage repair may provide leads for better control of spore outgrowth in foods.

  8. UV resistance of Bacillus anthracis spores revisited: validation of Bacillus subtilis spores as UV surrogates for spores of B. anthracis Sterne.

    Science.gov (United States)

    Nicholson, Wayne L; Galeano, Belinda

    2003-02-01

    Recent bioterrorism concerns have prompted renewed efforts towards understanding the biology of bacterial spore resistance to radiation with a special emphasis on the spores of Bacillus anthracis. A review of the literature revealed that B. anthracis Sterne spores may be three to four times more resistant to 254-nm-wavelength UV than are spores of commonly used indicator strains of Bacillus subtilis. To test this notion, B. anthracis Sterne spores were purified and their UV inactivation kinetics were determined in parallel with those of the spores of two indicator strains of B. subtilis, strains WN624 and ATCC 6633. When prepared and assayed under identical conditions, the spores of all three strains exhibited essentially identical UV inactivation kinetics. The data indicate that standard UV treatments that are effective against B. subtilis spores are likely also sufficient to inactivate B. anthracis spores and that the spores of standard B. subtilis strains could reliably be used as a biodosimetry model for the UV inactivation of B. anthracis spores.

  9. High-Resolution Spore Coat Architecture and Assembly of Bacillus Spores

    Energy Technology Data Exchange (ETDEWEB)

    Malkin, A J; Elhadj, S; Plomp, M

    2011-03-14

    Elucidating the molecular architecture of bacterial and cellular surfaces and its structural dynamics is essential to understanding mechanisms of pathogenesis, immune response, physicochemical interactions, environmental resistance, and provide the means for identifying spore formulation and processing attributes. I will discuss the application of in vitro atomic force microscopy (AFM) for studies of high-resolution coat architecture and assembly of several Bacillus spore species. We have demonstrated that bacterial spore coat structures are phylogenetically and growth medium determined. We have proposed that strikingly different species-dependent coat structures of bacterial spore species are a consequence of sporulation media-dependent nucleation and crystallization mechanisms that regulate the assembly of the outer spore coat. Spore coat layers were found to exhibit screw dislocations and two-dimensional nuclei typically observed on inorganic and macromolecular crystals. This presents the first case of non-mineral crystal growth patterns being revealed for a biological organism, which provides an unexpected example of nature exploiting fundamental materials science mechanisms for the morphogenetic control of biological ultrastructures. We have discovered and validated, distinctive formulation-specific high-resolution structural spore coat and dimensional signatures of B. anthracis spores (Sterne strain) grown in different formulation condition. We further demonstrated that measurement of the dimensional characteristics of B. anthracis spores provides formulation classification and sample matching with high sensitivity and specificity. I will present data on the development of an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures on the B. anthracis surfaces. These studies demonstrate that AFM can probe microbial surface architecture, environmental dynamics and the life cycle of bacterial and cellular systems at near

  10. Ptaquiloside in bracken spores from Britain

    DEFF Research Database (Denmark)

    Rasmussen, Lars Holm; Schmidt, Bjørn; Sheffield, Elizabeth

    2013-01-01

    Secondary metabolites from bracken fern (Pteridium aquilinum (L.) Kuhn) are suspected of causing cancer in humans. The main carcinogen is the highly water-soluble norsesquiterpene glucoside ptaquiloside, which may be ingested by humans through food, e.g. via contaminated water, meat or milk. It has...... in a collection of spores from Britain. Ptaquiloside was present in all samples, with a maximum of 29μgg−1, which is very low compared to other parts of the fern. Considering the low abundance of spores in breathing air under normal conditions, this exposure route is likely to be secondary to milk or drinking...

  11. Summoning the wind: Hydrodynamic cooperation of forcibly ejected fungal spores

    CERN Document Server

    Roper, Marcus; Cobb, Ann; Dillard, Helene R; Pringle, Anne

    2009-01-01

    The forcibly launched spores of the crop pathogen \\emph{Sclerotinia sclerotiorum} must eject through many centimeters of nearly still air to reach the flowers of the plants that the fungus infects. Because of their microscopic size, individually ejected spores are quickly brought to rest by drag. In the accompanying fluid dynamics video we show experimental and numerical simulations that demonstrate how, by coordinating the nearly simultaneous ejection of hundreds of thousands of spores,\\emph{Sclerotinia} and other species of apothecial fungus are able to sculpt a flow of air that carries spores across the boundary layer and around intervening obstacles. Many spores are sacrificed to create this flow of air. Although high speed imaging of spore launch in a wild isolate of the dung fungus \\emph{Ascobolus} shows that the synchronization of spore ejections is self-organized, which could lead to spores delaying their ejection to avoid being sacrificed, simulations and asymptotic analysis show that, close the frui...

  12. Measurement of Metabolic Activity in Dormant Spores of Bacillus Species

    Science.gov (United States)

    2015-01-14

    SECURITY CLASSIFICATION OF: Spores of Bacillus megaterium and Bacillus subtilis were harvested shortly after release from sporangia, incubated under...Dec-2014 Approved for Public Release; Distribution Unlimited Final Report: Measurement of Metabolic Activity in Dormant Spores of Bacillus Species...Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 spores, Bacillus , spore dormancy, 3-phosphoglycerate REPORT DOCUMENTATION PAGE 11

  13. Fifth international fungus spore conference. [Abstracts]: Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Timberlake, W.E.

    1993-04-01

    This folio contains the proceedings of the Fifth International Fungal Spore Conference held August 17-21, 1991 at the Unicoi State Park at Helen, Georgia. The volume contains abstracts of each oral presentation as well as a collection of abstracts describing the poster sessions. Presentations were organized around the themes (1) Induction of Sporulation, (2) Nuclear Division, (3) Spore Formation, (4) Spore Release and Dispersal, and (4) Spore Germination.

  14. Combined effects of carbonation with heating and fatty acid esters on inactivation and growth inhibition of various bacillus spores.

    Science.gov (United States)

    Klangpetch, Wannaporn; Nakai, Tomoe; Noma, Seiji; Igura, Noriyuki; Shimoda, Mitsuya

    2013-09-01

    The effects of carbonation treatment (1 to 5 MPa, 30 min) plus heat treatment (30 to 80°C, 30 min) in the presence of various fatty acid esters (FAEs; 0.05 and 0.1%, wt/vol) on counts of viable Bacillus subtilis spores were investigated. FAEs or carbonation alone had no inactivation or growth inhibition effects on B. subtilis spores. However, carbonation plus heat (CH; 80°C, 5 MPa, 30 min) in the presence of mono- and diglycerol fatty acid esters markedly decreased counts of viable spores, and the spore counts did not change during storage for 30 days. The greatest decrease in viable spore counts occurred in the presence of monoglycerol fatty acid esters. Under CH conditions, inactivation and/or growth inhibition occurred at only 80°C and increased with increasing pressure. The greatest decrease in spore counts (more than 4 log units) occurred with CH (80°C, 5 MPa, 30 min) in the presence of monoglycerol fatty acid esters. However, this treatment was less effective against Bacillus coagulans and Geobacillus stearothermophilus spores.

  15. Direct investigation of viscosity of an atypical inner membrane of Bacillus spores: a molecular rotor/FLIM study.

    Science.gov (United States)

    Loison, Pauline; Hosny, Neveen A; Gervais, Patrick; Champion, Dominique; Kuimova, Marina K; Perrier-Cornet, Jean-Marie

    2013-11-01

    We utilize the fluorescent molecular rotor Bodipy-C12 to investigate the viscoelastic properties of hydrophobic layers of bacterial spores Bacillus subtilis. The molecular rotor shows a marked increase in fluorescence lifetime, from 0.3 to 4ns, upon viscosity increase from 1 to 1500cP and can be incorporated into the hydrophobic layers within the spores from dormant state through to germination. We use fluorescence lifetime imaging microscopy to visualize the viscosity inside different compartments of the bacterial spore in order to investigate the inner membrane and relate its compaction to the extreme resistance observed during exposure of spores to toxic chemicals. We demonstrate that the bacterial spores possess an inner membrane that is characterized by a very high viscosity, exceeding 1000cP, where the lipid bilayer is likely in a gel state. We also show that this membrane evolves during germination to reach a viscosity value close to that of a vegetative cell membrane, ca. 600cP. The present study demonstrates quantitative imaging of the microscopic viscosity in hydrophobic layers of bacterial spores Bacillus subtilis and shows the potential for further investigation of spore membranes under environmental stress.

  16. Bacillus subtilis spores expressing the VP28 antigen: a potential oral treatment to protect Litopenaeus vannamei against white spot syndrome.

    Science.gov (United States)

    Nguyen, Anh T V; Pham, Cuong K; Pham, Huong T T; Pham, Hang L; Nguyen, Anh H; Dang, Lua T; Huynh, Hong A; Cutting, Simon M; Phan, Tuan-Nghia

    2014-09-01

    The envelope protein VP28 of white spot syndrome virus (WSSV) is considered a candidate antigen for use in a potential vaccine to this important shrimp pathogen (the cause of white spot syndrome, WSS). Here, we used spores of Bacillus subtilis to display VP28 on the spore surface. Trials were conducted to evaluate their ability to protect shrimps against WSSV infection. The gene cotB-vp28 was integrated into the chromosome of the laboratory strain B. subtilis PY79, and expression of CotB-VP28 was detected by Western blotting and immunofluorescence. Expression of CotB-VP28 was equivalent to 1000 molecules per spore. PY79 and CotB-VP28 spores were mixed with pellets for feeding of whiteleg shrimps (Litopenaeus vannamei), followed by WSSV challenge. Superoxidase dismutase (SOD), phenoloxidase activities and mortality rates of the two shrimp groups were evaluated. Groups fed with PY79 and CotB-VP28 spores at day 7 had increased SOD activities of 29% and increased phenoloxidase activities of 15% and 33%, respectively, compared to those of the control group. Fourteen days postchallenge, 35% of vaccinated shrimps had died compared to 49% of those fed naked spores (PY79) and 66% untreated, unchallenged animals. These data suggest that spores expressing VP28 have potential as a prophylactic treatment of WSS.

  17. 9 CFR 113.66 - Anthrax Spore Vaccine-Nonencapsulated.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Anthrax Spore Vaccine-Nonencapsulated. 113.66 Section 113.66 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Bacterial Vaccines § 113.66 Anthrax Spore Vaccine—Nonencapsulated. Anthrax Spore...

  18. Dendritic Cells Endocytose Bacillus Anthracis Spores: Implications for Anthrax Pathogenesis

    Science.gov (United States)

    2007-11-02

    Dendritic Cells Endocytose Bacillus anthracis Spores: Implications for Anthrax Pathogenesis1 Katherine C. Brittingham,* Gordon Ruthel,* Rekha G...germination and dissemination of spores. Found in high frequency throughout the respiratory track, dendritic cells (DCs) routinely take up foreign...COVERED - 4. TITLE AND SUBTITLE Dendritic cells endocytose Bacillus anthracis spores: implications for anthrax pathogenesis, The Journal of

  19. Imaging bacterial spores by soft-x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stead, A.D.; Ford, T.W. [Univ. of London, Surrey (United Kingdom); Judge, J. [Unilever plc, Sharnbrook (United Kingdom)] [and others

    1997-04-01

    Bacterial spores are able to survive dehydration, but neither the physiological nor structural basis of this have been fully elucidated. Furthermore, once hydrated, spores often require activation before they will germinate. Several treatments can be used to activate spores, but in the case of Bacillus subtlis the most effective is heat treatment. The physiological mechanism associated with activation is also not understood, but some workers suggest that the loss of calcium from the spores may be critical. However, just prior to germination, the spores change from being phase bright to phase dark when viewed by light microscopy. Imaging spores by soft x-ray microscopy is possible without fixation. Thus, in contrast to electron microscopy, it is possible to compare the structure of dehydrated and hydrated spores in a manner not possible previously. A further advantage is that it is possible to monitor individual spores by phase contrast light microscopy immediately prior to imaging with soft x-rays; whereas, with both electron microscopy and biochemical studies, it is a population of spores being studied without knowledge of the phase characteristics of individual spores. This study has therefore tried to compare dehydrated and hydrated spores and to determine if there is a mass loss from individual spores as they pass the transition from being phase bright to phase dark.

  20. Toxicity of terpenes to spores and mycelium of Penicillium digitatum

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, M.J. van der

    2002-01-01

    Spores, although often considered metabolically inert, catalyze a variety of reactions. The use of spores instead of mycelium for bioconversions has several advantages. In this paper, we describe the difference in susceptibility of mycelium and spores against toxic substrates and products. A higher

  1. Toxicity of terpenes to spores and mycelium op Penicillium digitatum

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, van der M.J.

    2002-01-01

    Spores, although often considered metabolically inert, catalyze a variety of reactions. The use of spores instead of mycelium for bioconversions has several advantages. In this paper, we describe the difference in susceptibility of mycelium and spores against toxic substrates and products. A higher

  2. Geraniol biotransformation-pathway in spores of Penicillium digitatum

    NARCIS (Netherlands)

    Wolken, W.A.M.; Werf, M.J. van der

    2001-01-01

    Spores of Penicillium digitatum ATCC 201167 transform geraniol, nerol, citral, and geranic acid into methylheptenone. Spore extracts of P. digitatum convert geraniol and nerol NAD+-dependently into citral. Spore extract also converts citral NAD+-dependently into geranic acid. Furthermore, a novel en

  3. Mechanisms of Resistance in Microbial Spores

    Science.gov (United States)

    1990-12-20

    solids (and water) content by immersion refractometry . Heat-activated spores of Bacillus stearotherrnophilus were found to be separable into two...incrC· ment of bacterial cells, enabling determination of their solids content by immersion refractometry . The results agreed well with values for

  4. Airborne myxomycete spores: detection using molecular techniques

    Science.gov (United States)

    Kamono, Akiko; Kojima, Hisaya; Matsumoto, Jun; Kawamura, Kimitaka; Fukui, Manabu

    2009-01-01

    Myxomycetes are organisms characterized by a life cycle that includes a fruiting body stage. Myxomycete fruiting bodies contain spores, and wind dispersal of the spores is considered important for this organism to colonize new areas. In this study, the presence of airborne myxomycetes and the temporal changes in the myxomycete composition of atmospheric particles (aerosols) were investigated with a polymerase chain reaction (PCR)-based method for Didymiaceae and Physaraceae. Twenty-one aerosol samples were collected on the roof of a three-story building located in Sapporo, Hokkaido Island, northern Japan. PCR analysis of DNA extracts from the aerosol samples indicated the presence of airborne myxomycetes in all the samples, except for the one collected during the snowfall season. Denaturing gradient gel electrophoresis (DGGE) analysis of the PCR products showed seasonally varying banding patterns. The detected DGGE bands were subjected to sequence analyses, and four out of nine obtained sequences were identical to those of fruiting body samples collected in Hokkaido Island. It appears that the difference in the fruiting period of each species was correlated with the seasonal changes in the myxomycete composition of the aerosols. Molecular evidence shows that newly formed spores are released and dispersed in the air, suggesting that wind-driven dispersal of spores is an important process in the life history of myxomycetes. This study is the first to detect airborne myxomycetes with the use of molecular ecological analyses and to characterize their seasonal distribution.

  5. Myxomycete (slime mold) spores: unrecognized aeroallergens?

    Science.gov (United States)

    Lierl, Michelle B

    2013-12-01

    Myxomycete spores are present in the outdoor air but have not been studied for allergenicity. To determine whether patients with seasonal allergic rhinitis (SAR) symptoms are sensitized to myxomycete spores. Myxomycete specimens were collected in the field. Nine species of myxomycetes were collected and identified: Arcyria cinerea, Ceratiomyxa fruticulosa, Fuligo septica, Hemitrichia clavata, Lycogala epidendrum, Metatrichia vesparium, Stemonitis nigrescens, Tubifera ferruginosa, and Trichea favoginea. Allergen extracts were made for each species. Protein content of each extract was measured by bicinchoninic acid assay. Protein electrophoresis was performed. Subjects with a history of SAR symptoms were enrolled, and allergy skin prick testing was performed with each extract. Protein content of the extracts ranged from 1.05 to 5.8 mg/mL. Protein bands were seen at 10 to 250 kD. Allergy prick testing was performed in 69 subjects; 42% of subjects had positive prick test results for at least 1 myxomycete extract, with 9% to 22% reacting to each extract. Five of the 12 subjects who tested negative for all allergens on the standard aeroallergen panel had positive prick test results for myxomycetes. Forty-two percent of subjects with SAR were sensitized to myxomycete spores. A significant subset of subjects who had SAR symptoms and otherwise negative skin test results showed sensitization to myxomycetes. These spores are present in the outdoor air during the summer and autumn and might be significant aeroallergens. Copyright © 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  6. Phospholipase Cδ regulates germination of Dictyostelium spores

    NARCIS (Netherlands)

    Dijken, Peter van; Haastert, Peter J.M. van

    2001-01-01

    Background: Many eukaryotes, including plants and fungi make spores that resist severe environmental stress. The micro-organism Dictyostelium contains a single phospholipase C gene (PLC); deletion of the gene has no effect on growth, cell movement and differentiation. In this report we show that PLC

  7. Phospholipase Cδ regulates germination of Dictyostelium spores

    NARCIS (Netherlands)

    Dijken, Peter van; Haastert, Peter J.M. van

    2001-01-01

    Background: Many eukaryotes, including plants and fungi make spores that resist severe environmental stress. The micro-organism Dictyostelium contains a single phospholipase C gene (PLC); deletion of the gene has no effect on growth, cell movement and differentiation. In this report we show that PLC

  8. Studies on the bacterial spore coat 6 effects of alkali extraction on the spore of Bacillus thiaminolyticus.

    Science.gov (United States)

    Minami, J; Ichikawa, T; Kondo, M

    1977-01-01

    Thin sections of the spore of Bacillus thiaminolyticus Matsukawa and Misawa show a characteristic surface structure with five ridges, and a series of three district layers. The outer layer of the spore coat was peeled off by SDS sonic treatment, and than the middle layer was solubilized by alkali extraction of the SDS sonic-treated spore. The spores subjected to these treatments were still refractile, heat resistant, and contained dipicolinic acid, but lost their resistance to mechanical shock.

  9. Monitoring Rates and Heterogeneity of High-Pressure Germination of Bacillus Spores by Phase-Contrast Microscopy of Individual Spores

    Science.gov (United States)

    2014-01-01

    SECURITY CLASSIFICATION OF: The germination of multiple individual Bacillus subtilis spores by a high pressure (HP) of 140-150 (unless noted...otherwise) megaPascals (MPa) that activates spore germinant receptors (GRs) was monitored by phase contrast microscopy in a diamond anvil cell. Major...conclusions were that: i) >95% of spores germinated in 40 min; ii) individual spore’s HP germination kinetics were very similar to those for nutrient

  10. A Generic Method for Fungal Spore Detection: The use of a monoclonal antibody and surface plasmon resonance

    DEFF Research Database (Denmark)

    Skottrup, Peter; Hearty, Stephen; Frøkiær, Hanne;

    2005-01-01

    This study describes a biosensing principle for detection of fungal spores using surface plasmon resonance (SPR). The approach involves the use of a monoclonal antibody (mab) and a SPR sensor for label-free detection of the model organism Puccinia striiformis f.sp. tritici (Pst) a biotrophic fungus...... binding of mab to the sensor surface was observed as the Pst urediniospore concentration was increased. The detection range for the assay was 1.7 x 106 – 5.3 x 104 spores/ml. This study describes the first use of SPR for detection of fungal spores and the generic principle has the potential to be used...

  11. Inactivation of three genera of dominant fungal spores in groundwater using chlorine dioxide: Effectiveness, influencing factors, and mechanisms.

    Science.gov (United States)

    Wen, Gang; Xu, Xiangqian; Huang, Tinglin; Zhu, Hong; Ma, Jun

    2017-08-18

    Fungi in aquatic environments received more attention recently; therefore, the characteristics of inactivation of fungal spores by widely used disinfectants are quite important. Nonetheless, the inactivation efficacy of fungal spores by chlorine dioxide is poorly known. In this study, the effectiveness of chlorine dioxide at inactivation of three dominant genera of fungal spores isolated from drinking groundwater and the effects of pH, temperature, chlorine dioxide concentration, and humic acid were evaluated. The inactivation mechanisms were explored by analyzing the leakage of intracellular substances, the increase in extracellular adenosine triphosphate (ATP), deoxyribonucleic acid (DNA), and proteins as well as the changes in spore morphology. The kinetics of inactivation by chlorine dioxide fitted the Chick-Watson model, and different fungal species showed different resistance to chlorine dioxide inactivation, which was in the following order: Cladosporium sp.>Trichoderma sp. >Penicillium sp., which are much more resistant than Escherichia coli. Regarding the three genera of fungal spores used in this study, chlorine dioxide was more effective at inactivation of fungal spores than chlorine. The effect of disinfectant concentration and temperature was positive, and the impact of pH levels (6.0 and 7.0) was insignificant, whereas the influence of water matrices on the inactivation efficiency was negative. The increased concentration of characteristic extracellular substances and changes of spore morphology were observed after inactivation with chlorine dioxide and were due to cell wall and cell membrane damage in fungal spores, causing the leakage of intracellular substances and death of a fungal spore. Copyright © 2017. Published by Elsevier Ltd.

  12. Immunomodulatory effects of Bacillus subtilis (natto) B4 spores on murine macrophages.

    Science.gov (United States)

    Xu, Xin; Huang, Qin; Mao, Yulong; Cui, Zhiwen; Li, Yali; Huang, Yi; Rajput, Imran Rashid; Yu, Dongyou; Li, Weifen

    2012-12-01

    To investigate the immunomodulatory effects of Bacillus subtilis (B. subtilis) (natto) B4 spores on murine macrophage, RAW 264.7 cells were cultured alone or with B subtilis (natto) B4 spores at 37°C for 12 hrs, then both cells and culture supernatants were collected for analyses. Exposure of RAW 264.7 cells to B. subtilis (natto) B4 spores had no significant effects on macrophage viability and amounts of extracellular lactate dehydrogenase (LDH). However, it remarkably increased the activities of acid phosphatase (ACP), lactate dehydrogenase (LDH) and inducible nitric oxide synthase (iNOS) in cells and the amounts of nitric oxide (NO) and cytokines (tumor necrosis factor-alpha, interferon-gamma, interleukin [IL]-1 beta, IL-6, IL-12, IL-10 and macrophage inflammatory protein-2) in culture supernatants. These results demonstrate that B. subtilis (natto) B4 spores are harmless to murine macrophages and can stimulate their activation through up-regulation of ACP and LDH activities and enhance their immune function by increasing iNOS activity and stimulating NO and cytokine production. The above findings suggest that B. subtilis (natto) B4 spores have immunomodulatory effects on macrophages. © 2012 The Societies and Wiley Publishing Asia Pty Ltd.

  13. Absence of Fungal Spore Internalization by Bronchial Epithelium in Mouse Models Evidenced by a New Bioimaging Approach and Transmission Electronic Microscopy.

    Science.gov (United States)

    Rammaert, Blandine; Jouvion, Grégory; de Chaumont, Fabrice; Garcia-Hermoso, Dea; Szczepaniak, Claire; Renaudat, Charlotte; Olivo-Marin, Jean-Christophe; Chrétien, Fabrice; Dromer, Françoise; Bretagne, Stéphane

    2015-09-01

    Clinical data and experimental studies suggest that bronchial epithelium could serve as a portal of entry for invasive fungal infections. We therefore analyzed the interactions between molds and the bronchial/bronchiolar epithelium at the early steps after inhalation. We developed invasive aspergillosis (Aspergillus fumigatus) and mucormycosis (Lichtheimia corymbifera) murine models that mimic the main clinical risk factors for these infections. Histopathology studies were completed with a specific computer-assisted morphometric method to quantify bronchial and alveolar spores and with transmission electron microscopy. Morphometric analysis revealed a higher number of bronchial/bronchiolar spores for A. fumigatus than L. corymbifera. The bronchial/bronchiolar spores decreased between 1 and 18 hours after inoculation for both fungi, except in corticosteroid-treated mice infected with A. fumigatus, suggesting an effect of cortisone on bronchial spore clearance. No increase in the number of spores of any species was observed over time at the basal pole of the epithelium, suggesting the lack of transepithelial crossing. Transmission electron microscopy did not show spore internalization by bronchial epithelial cells. Instead, spores were phagocytized by mononuclear cells on the apical pole of epithelial cells. Early epithelial internalization of fungal spores in vivo cannot explain the bronchial/bronchiolar epithelium invasion observed in some invasive mold infections. The bioimaging approach provides a useful means to accurately enumerate and localize the fungal spores in the pulmonary tissues.

  14. Detection of chlorophylls in spores of seven ferns.

    Science.gov (United States)

    Tseng, Mei-Hwei; Lin, Kuei-Huei; Huang, Yi-Jia; Chang, Ya-Lan; Huang, Sheng-Cih; Kuo, Li-Yaung; Huang, Yao-Moan

    2017-03-01

    Fern spores were traditionally classified into chlorophyllous (green) and nonchlorophyllous (nongreen) types based on the color visible to the naked eye. Recently, a third type, "cryptochlorophyllous spores", is recognized, and these spores are nongreen under white light but contain chlorophylls. Epifluorescence microscopy was previously used to detect chlorophylls in cryptochlorophyllous spores. In addition to epifluorescence microscopy, current study performed some other approaches, including spore-squash epifluorescence, absorption spectra, laser-induced fluorescence emission spectra, thin layer chromatography (TLC), and ultra-high performance liquid chromatography with ultraviolet and mass spectrometric detection (UHPLC-UV-MS) in order to detect chlorophylls of spores of seven ferns (Sphaeropteris lepifera, Ceratopteris thalictroides, Leptochilus wrightii, Leptochilus pothifolius, Lepidomicrosorum buergerianum, Osmunda banksiifolia, and Platycerium grande). Destructive methods, such as TLC and UHPLC-UV-MS, successfully detected chlorophylls inside the spores when their signals of red fluorescence under epifluorescence microscope were masked by spore wall. Although UHPLC-UV-MS analysis was the most sensitive and reliable for determining the chlorophylls of spores, spore-squash epifluorescence is not only reliable but also cost- and time-effective one among our study methods. In addition, we first confirmed that Lepidomicrosorium buergerianum, Leptochilus pothifolius, Leptochilus wrightii, and Platycerium grande, produce cryptochlorophyllous spores.

  15. Inactivation of Clostridium difficile spores by microwave irradiation.

    Science.gov (United States)

    Ojha, Suvash Chandra; Chankhamhaengdecha, Surang; Singhakaew, Sombat; Ounjai, Puey; Janvilisri, Tavan

    2016-04-01

    Spores are a potent agent for Clostridium difficile transmission. Therefore, factors inhibiting spores have been of continued interest. In the present study, we investigated the influence of microwave irradiation in addition to conductive heating for C. difficile spore inactivation in aqueous suspension. The spores of 15 C. difficile isolates from different host origins were exposed to conductive heating and microwave irradiation. The complete inhibition of spore viability at 10(7) CFU/ml was encountered following microwave treatment at 800 W for 60 s, but was not observed in the conductive-heated spores at the same time-temperature exposure. The distinct patterns of ultrastructural alterations following microwave and conductive heat treatment were observed and the degree of damages by microwave was in the exposure time-dependent manner. Microwave would therefore be a simple and time-efficient tool to inactivate C. difficile spores, thus reducing the risk of C. difficile transmission.

  16. INCORPORATION OF BACTERIOPHAGE GENOME BY SPORES OF BACILLUS SUBTILIS.

    Science.gov (United States)

    TAKAHASHI, I

    1964-06-01

    Takahashi, I. (Microbiology Research Institute, Ottawa, Ontario, Canada). Incorporation of bacteriophage genome by spores of Bacillus subtilis. J. Bacteriol. 87:1499-1502. 1964-The buoyant density in a CsCl gradient of deoxyribonucleic acid (DNA) extracted from spores of Bacillus subtilis was found to be identical to that of DNA from vegetative cells. Density-gradient centrifugation of DNA of spores derived from cultures infected with phage PBS 1 revealed the presence of a minor band whose density corresponded to that of the phage DNA in addition to the spore DNA. No intermediate bands were present. The relative amount of the phage DNA present in the spores was estimated to be 11%, suggesting that spores of this organism may incorporate several copies of the phage genome. Although the possibility that true lysogeny may occur cannot be entirely eliminated, the results seem to indicate that the phage genomes incorporated into spores are not attached to the host chromosome in this system.

  17. Determination of fungal spore release from wet building materials

    DEFF Research Database (Denmark)

    Kildesø, J.; Wurtz, H.; Nielsen, Kristian Fog;

    2003-01-01

    of fungal spores was induced by well-defined jets of air impacting from rotating nozzles. The spores and other particles released from the surface were transported by the air flowing from the chamber through a top outlet to a particle counter and sizer. For two of the fungi (Penicillium chrysogenum...... and Trichoderma harzianum ), the number of spores produced on the gypsum board and subsequently released was quantified. Also the relationship between air velocities from 0.3 to 3 m/s over the surface and spore release has been measured. The method was found to give very reproducible results for each fungal...... isolate, whereas the spore release is very different for different fungi under identical conditions. Also, the relationship between air velocity and spore release depends on the fungus. For some fungi a significant number of particles smaller than the spore size were released. The method applied...

  18. Mushroom spore dispersal by convectively-driven winds

    CERN Document Server

    Dressaire, Emilie; Song, Boya; Roper, Marcus

    2015-01-01

    Thousands of fungal species rely on mushroom spores to spread across landscapes. It has long been thought that spores depend on favorable airflows for dispersal -- that active control of spore dispersal by the parent fungus is limited to an impulse delivered to the spores to carry them clear of the gill surface. Here we show that evaporative cooling of the air surrounding the mushroom pileus creates convective airflows capable of carrying spores at speeds of centimeters per second. Convective cells can transport spores from gaps that may be only a centimeter high, and lift spores ten centimeters or more into the air. The work reveals how mushrooms tolerate and even benefit from crowding, and provides a new explanation for their high water needs.

  19. Bacterial spore structures and their protective role in biocide resistance.

    Science.gov (United States)

    Leggett, M J; McDonnell, G; Denyer, S P; Setlow, P; Maillard, J-Y

    2012-09-01

    The structure and chemical composition of bacterial spores differ considerably from those of vegetative cells. These differences largely account for the unique resistance properties of the spore to environmental stresses, including disinfectants and sterilants, resulting in the emergence of spore-forming bacteria such as Clostridium difficile as major hospital pathogens. Although there has been considerable work investigating the mechanisms of action of many sporicidal biocides against Bacillus subtilis spores, there is far less information available for other species and particularly for various Clostridia. This paucity of information represents a major gap in our knowledge given the importance of Clostridia as human pathogens. This review considers the main spore structures, highlighting their relevance to spore resistance properties and detailing their chemical composition, with a particular emphasis on the differences between various spore formers. Such information will be vital for the rational design and development of novel sporicidal chemistries with enhanced activity in the future.

  20. [Bacterial spore--a new vaccine vehicle--a review].

    Science.gov (United States)

    Wang, Yanchun; Zhang, Zhaoshan

    2008-03-01

    Bacterial spores are robust and dormant life forms with formidable resistance properties. Spores of the genus Bacillus have been used for a long time as probiotics for oral bacteriotherapy both in humans and animals. Recently, genetically modified B. subtilis spores and B. anthracis spores have been used as indestructible delivery vehicles for vaccine antigens. They were used as vaccine vehicles or spore vaccine for oral immunization against tetanus and anthrax, and the results were very exciting. Unlike many second generation vaccine systems currently under development, bacterial spores offer heat stability and the flexibility for genetic manipulation. At the same time, they can elicit mucosal immune response by oral and nasal administration. This review focuses on the use of recombinant spores as vaccine delivery vehicles.

  1. Efficacy of gaseous chlorine dioxide in inactivating Bacillus cereus spores attached to and in a biofilm on stainless steel.

    Science.gov (United States)

    Nam, Hyegyeong; Seo, Hyun-Sun; Bang, Jihyun; Kim, Hoikyung; Beuchat, Larry R; Ryu, Jee-Hoon

    2014-10-01

    We evaluated the lethal activity of gaseous chlorine dioxide (ClO2) against Bacillus cereus spores attached to and in biofilm formed on a stainless steel surface. Aqueous ClO2 was prepared by mixing sulfuric acid (5% w/v) with sodium chlorite (10mg/mL), and gaseous ClO2 was produced by vaporization of aqueous ClO2 in an air-tight container. The concentration of gaseous ClO2 in the air within the container increased rapidly at first but gradually decreased over time. The lethality of gaseous ClO2 against B. cereus spores attached to stainless steel coupons (SSCs) and in biofilm formed by the pathogen on SSCs was determined. The B. cereus spores attached to SSCs (5.3±0.1logCFU/coupon) were completely inactivated within 1h at 25°C when treated with gaseous ClO2 (peak concentration: 115.3±5.0 parts per million [ppm]). The total number of vegetative cells and spores in biofilm formed by B. cereus on SSCs was 5.9±0.3logCFU/coupon; the spore count was 5.3±0.1logCFU/coupon. The vegetative cells and spores in biofilm were completely inactivated within 6h (peak concentration: 115.3±5.0ppm). Results show that B. cereus spores in biofilms are more resistant to gaseous ClO2 than are attached spores not in biofilms. Gaseous ClO2 was, nevertheless, very effective in killing B. cereus spores in biofilm on the surface of stainless steel. Results show promise for application of gaseous ClO2 to enhance the microbiological safety of foods that may come in contact with stainless steel and possibly other hard surfaces on which B. cereus biofilms have formed.

  2. Meteorological and agricultural effects on airborne Alternaria and Cladosporium spores and clinical aspects in Valladolid (Spain).

    Science.gov (United States)

    Reyes, Estefanía Sánchez; de la Cruz, David Rodríguez; Merino, Ma Eugenia Sanchís; Sánchez, José Sánchez

    2009-01-01

    The aeropalynological monitoring was carried out from 1 February 2005-31 January 2007. The total number of spores collected during the main spore season (MSS) in 2005 was 4,500 for Alternaria and 93,744 in the case of Cladosporium, whereas in 2006 values were increased (8,385 for Alternaria and 150,144 for Cladosporium), reaching the maximum concentrations on 18 July and 17 June 2006 with 344 and 5,503 spores, respectively. The influence of the main meteorological parameters on spore concentrations was studied, resulting in a positive correlation with temperature. Rainfall, relative humidity and frequency of calms obtained negative correlations in the case of Alternaria, and positive for Cladosporium, the total daily hours of sunshine having an inverse influence on them. The intra-diurnal pattern was very similar for both genera, with a greater representation towards the central hours of the day and at night. Finally, some clinical aspects for the Alternaria spore type were analyzed, with a low percentage of sensitized patients though (9.5%). Only one patient showed positive skin test reaction to Cladosporium.

  3. Bacterial spore heat resistance correlated with water content, wet density, and protoplast/sporoplast volume ratio.

    Science.gov (United States)

    Beaman, T C; Greenamyre, J T; Corner, T R; Pankratz, H S; Gerhardt, P

    1982-05-01

    Five types of dormant Bacillus spores, between and within species, were selected representing a 600-fold range in moist-heat resistance determined as a D100 value. The wet and dry density and the solids and water content of the entire spore and isolated integument of each type were determined directly from gram masses of material, with correction for interstitial water. The ratio between the volume occupied by the protoplast (the structures bounded by the inner pericytoplasm membrane) and the volume occupied by the sporoplast (the structures bounded by the outer pericortex membrane) was calculated from measurements made on electron micrographs of medially thin-sectioned spores. Among the various spore types, an exponential increase in the heat resistance correlated directly with the wet density and inversely with the water content and with the protoplast/sporoplast volume ratio. Altogether with results supported a hypothesis that the extent of heat resistance is based in whole or in part on the extent of dehydration and diminution of the protoplast in the dormant spore, without implications about physiological mechanisms for attaining this state.

  4. MICROFILTRATION AND ULTRAFILTRATION OF Bacillus thuringiensis FERMENTATION BROTH: MEMBRANE PERFORMANCE AND SPORE-CRYSTAL RECOVERY APPROACHES

    Directory of Open Access Journals (Sweden)

    R. Marzban

    Full Text Available Abstract Recovery of spores and crystals from the fermentation broth of Bacillus thuringiensis (Bt was studied using the membrane separation technology. Four types of polymeric membranes, with different characteristics, in the range of microfiltration (MF and ultrafiltration (UF were used for evaluating their permeate flux and spore-crystal recovery capacity. Results indicated that both MF and UF membranes are effective for spore-crystal recovery. The hydrophobic MF membrane made of polyvinylidene fluoride (PVDF achieved a better performance compared to the one made with hydrophilic cellulose acetate (CA. Both had a 0.22 µm pore size, under the condition of an upper range of feed pressure. Also, with the increase of the feed flow rate, a higher flux was achieved for the PVDF membrane. A UF membrane made of polyethersulfone (PES polymer was also used effectively for spore/crystal recovery from the broth, but under a higher operating pressure. In the entire experiment, a 99.9% rejection factor was measured with the applied membranes for the spore/crystal in the fermentation broth.

  5. Spore Heat Activation Requirements and Germination Responses Correlate with Sequences of Germinant Receptors and with the Presence of a Specific spoVA(2mob) Operon in Foodborne Strains of Bacillus subtilis.

    Science.gov (United States)

    Krawczyk, Antonina O; de Jong, Anne; Omony, Jimmy; Holsappel, Siger; Wells-Bennik, Marjon H J; Kuipers, Oscar P; Eijlander, Robyn T

    2017-04-01

    Spore heat resistance, germination, and outgrowth are problematic bacterial properties compromising food safety and quality. Large interstrain variation in these properties makes prediction and control of spore behavior challenging. High-level heat resistance and slow germination of spores of some natural Bacillus subtilis isolates, encountered in foods, have been attributed to the occurrence of the spoVA(2mob) operon carried on the Tn1546 transposon. In this study, we further investigate the correlation between the presence of this operon in high-level-heat-resistant spores and their germination efficiencies before and after exposure to various sublethal heat treatments (heat activation, or HA), which are known to significantly improve spore responses to nutrient germinants. We show that high-level-heat-resistant spores harboring spoVA(2mob) required higher HA temperatures for efficient germination than spores lacking spoVA(2mob) The optimal spore HA requirements additionally depended on the nutrients used to trigger germination, l-alanine (l-Ala), or a mixture of l-asparagine, d-glucose, d-fructose, and K(+) (AGFK). The distinct HA requirements of these two spore germination pathways are likely related to differences in properties of specific germinant receptors. Moreover, spores that germinated inefficiently in AGFK contained specific changes in sequences of the GerB and GerK germinant receptors, which are involved in this germination response. In contrast, no relation was found between transcription levels of main germination genes and spore germination phenotypes. The findings presented in this study have great implications for practices in the food industry, where heat treatments are commonly used to inactivate pathogenic and spoilage microbes, including bacterial spore formers.IMPORTANCE This study describes a strong variation in spore germination capacities and requirements for a heat activation treatment, i.e., an exposure to sublethal heat that increases

  6. Maternal parentage influences spore production but not spore pigmentation in the anisogamous and hermaphroditic fungus Neurospora crassa

    DEFF Research Database (Denmark)

    Zimmerman, Kolea; Levitis, Daniel; Pringle, Anne

    2014-01-01

    , and various ascospore characteristics. Mixed effects models of these data show that the female parent accounts for the majority of variation in perithecial production, number of spores produced, and spore germination. Surprisingly, both sexes equally influence the percentage of spores that are pigmented....... In this fungus, pigmented spores are viable and unpigmented spores are inviable. These results show that while both parents influence all these traits, maternal influence is strongest on both fertility and mortality traits until the spores are physiologically independent of the maternal cytoplasm......., Hall, & Kowbel 2011). Precise genetic distances between mating pairs were calculated to control for the effects of crossing distance on offspring production. We performed reciprocal crosses of all 121 strain pairings and collected data on perithecial production, ascospore (sexual spore) production...

  7. CLOSTRIDIUM SPORE ATTACHMENT TO HUMAN CELLS

    Energy Technology Data Exchange (ETDEWEB)

    PANESSA-WARREN,B.; TORTORA,G.; WARREN,J.

    1997-08-10

    This paper uses high resolution scanning electron microscopy (SEM) with a LaB6 gun and the newest commercial field emission guns, to obtain high magnification images of intact clostridial spores throughout the activation/germination/outgrowth process. By high resolution SEM, the clostridial exosporial membrane can be seen to produce numerous delicate projections (following activation), that extend from the exosporial surface to a nutritive substrate (agar), or cell surface when anaerobically incubated in the presence of human cells (embryonic fibroblasts and colon carcinoma cells). Magnifications of 20,000 to 200,000Xs at accelerating voltages low enough to minimize or eliminate specimen damage (1--5 kV) have permitted the entire surface of C.sporogenes and C.difficile endospores to be examined during all stages of germination. The relationships between the spore and the agar or human cell surface were also clearly visible.

  8. Phosphoproteome dynamics mediate revival of bacterial spores

    OpenAIRE

    2015-01-01

    Background Bacterial spores can remain dormant for decades, yet harbor the exceptional capacity to rapidly resume metabolic activity and recommence life. Although germinants and their corresponding receptors have been known for more than 30 years, the molecular events underlying this remarkable cellular transition from dormancy to full metabolic activity are only partially defined. Results Here, we examined whether protein phospho-modifications occur during germination, the first step of exit...

  9. Quantification of the impact of single and multiple mild stresses on outgrowth heterogeneity of Bacillus cereus spores.

    Science.gov (United States)

    van Melis, C C J; den Besten, H M W; Nierop Groot, M N; Abee, T

    2014-05-02

    Outgrowth heterogeneity of bacterial spore populations complicates both prediction and efficient control of spore outgrowth. In this study, the impact of mild preservation stresses on outgrowth of Bacillus cereus ATCC 14579 spores was quantified during the first stages of outgrowth. Heterogeneity in outgrowth of heat-treated (90°C for 10 min) and non-heat-treated germinated single spores to the maximum micro-colony stage of 256 cells was assessed by direct imaging on Anopore strips, placed on BHI plates at pH7 and pH5.5, without and with added NaCl or sorbic acid (HSA). At pH7 non-heated and heat-treated germinated spores required 6h to reach the maximum microcolony stage with limited heterogeneity, and these parameters were only slightly affected with both types of spores when incubated at pH7 with added NaCl. Notably, the most pronounced effects were observed during outgrowth of spores at pH5.5 without and with added NaCl or HSA. Non-heat-treated germinated spores showed again efficient outgrowth with limited heterogeneity reaching the maximum microcolony stage after 6h at pH5.5, which increased to 12h and 16 h with added NaCl and HSA, respectively. In contrast, heat-treated spores displayed a strong delay between initial germination and swelling and further outgrowth at pH5.5, resulting in large heterogeneity and low numbers of fastest growers reaching the maximum microcolony stage after 10, 12 and 24h, without and with added NaCl or HSA, respectively. This work shows that Anopore technology provides quantitative information on the impact of combined preservation stresses on outgrowth of single spores, showing that outgrowth of germinated heat-treated spores is significantly affected at pH5.5 with a large fraction of spores arrested in the early outgrowth stage, and with outgrowing cells showing large heterogeneity with only a small fraction committed to relatively fast outgrowth.

  10. Enhanced specificity of bacterial spore identification by oxidation and mass spectrometry.

    Science.gov (United States)

    Demirev, Plamen A

    2004-01-01

    Addition of an oxidizing agent (e.g., hydrogen peroxide) to intact spores selectively and completely oxidizes Met-containing biomarker proteins by formation of Met sulfoxides. This reaction increases the masses of the biomarker proteins observed in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of Bacillus spores by Deltam = (16 x n) Da, where n is the number of Met residues in the sequence of each individual protein. The procedure is very rapid, and can be performed in situ (i.e., on the MALDI target). It confirms the identity of individual biomarkers by comparing the number of Met amino acids from the experimentally determined mass shifts with predictions for n from the tentative amino acid sequence for each protein. In turn, accurate determination of n for several biomarkers allows rapid validation of the initial spore identification by MALDI-MS.

  11. Observation of the dynamic germination of single bacterial spores using rapid Raman imaging

    Science.gov (United States)

    Kong, Lingbo; Setlow, Peter; Li, Yong-qing

    2014-01-01

    The dynamics of bacterial spore germination were successfully observed using a fast Raman imaging system, in combination with real-time phase contrast microscopy. By using a multifocus scan scheme, the spontaneous Raman-scattering imaging acquisition speed was increased to ˜30 s per frame while maintaining diffraction-limited resolution, which allowed monitoring of the dynamics of spore germination on a time scale of tens of seconds to a few minutes. This allowed simultaneous gathering of rich spatial distribution information on different cellular components including time-lapse molecular images of Ca-dipicolinic acid, protein, and nucleic acid during germination of single bacterial spores for the periods of 30 to 60 min.

  12. Methyl Iodide Fumigation of Bacillus anthracis Spores.

    Science.gov (United States)

    Sutton, Mark; Kane, Staci R; Wollard, Jessica R

    2015-09-01

    Fumigation techniques such as chlorine dioxide, vaporous hydrogen peroxide, and paraformaldehyde previously used to decontaminate items, rooms, and buildings following contamination with Bacillus anthracis spores are often incompatible with materials (e.g., porous surfaces, organics, and metals), causing damage or residue. Alternative fumigation with methyl bromide is subject to U.S. and international restrictions due to its ozone-depleting properties. Methyl iodide, however, does not pose a risk to the ozone layer and has previously been demonstrated as a fumigant for fungi, insects, and nematodes. Until now, methyl iodide has not been evaluated against Bacillus anthracis. Sterne strain Bacillus anthracis spores were subjected to methyl iodide fumigation at room temperature and at 550C. Efficacy was measured on a log-scale with a 6-log reduction in CFUs being considered successful compared to the U.S. Environmental Protection Agency biocide standard. Such efficacies were obtained after just one hour at 55 °C and after 12 hours at room temperature. No detrimental effects were observed on glassware, PTFE O-rings, or stainless steel. This is the first reported efficacy of methyl iodide in the reduction of Bacillus anthracis spore contamination at ambient and elevated temperatures.

  13. Application of X-ray microscopy in food science investigation of high pressure affected bacterial spores

    Science.gov (United States)

    Mönch, Susanne; Heinz, Volker; Guttmann, Peter; Knorr, Dietrich

    2000-05-01

    Using the Göttingen transmission X-ray microscope at BESSY the effect of different pressure and temperature levels during the high hydrostatic pressure (HP) treatment was investigated. At 150 MPa and temperatures up to 50 °C the triggering of germination was observed by standard microbiological methods with Bacillus subtilis spores. Increasing the temperature to 70 °C at the same pressure level killed the spores without any indication of germination. By X-ray microscopy images it could be shown that the typical disintegration of the protoplast is inhibited. This suggests that the enzymic reaction pathway is possibly affected under specific pressure temperature conditions.

  14. Role of YpeB in Cortex Hydrolysis during Germination of Bacillus anthracis Spores

    OpenAIRE

    2014-01-01

    The infectious agent of the disease anthrax is the spore of Bacillus anthracis. Bacterial spores are extremely resistant to environmental stresses, which greatly hinders spore decontamination efforts. The spore cortex, a thick layer of modified peptidoglycan, contributes to spore dormancy and resistance by maintaining the low water content of the spore core. The cortex is degraded by germination-specific lytic enzymes (GSLEs) during spore germination, rendering the cells vulnerable to common ...

  15. Thirty-four identifiable airborne fungal spores in Havana, Cuba

    Directory of Open Access Journals (Sweden)

    Michel Almaguer

    2015-05-01

    Full Text Available The airborne fungal spore content in Havana, Cuba, collected by means a non-viable volumetric methodology, was studied from November 2010 – October 2011. The study, from a qualitative point of view, allowed the characterization of 29 genera and 5 fungal types, described following the Saccardo´s morphotypes, as well as their morphobiometrical characteristics. In the amerospores morphotype, the conidia of 7 genera (with ascospores, basidiospores and uredospores and 5 fungal types were included. Among phragmospores morphotype, the ascospores and conidia of 12 different genera were identified. The dictyospores morphotype only included conidial forms from 6 genera. Finally, the less frequent morphotypes were staurospores, didymospores and distosepted spores. In general, the main worldwide spread mitosporic fungi also predominated in the Havana atmosphere, accompanied by some ascospores and basidiospores. [i]Cladosporium[/i] cladosporioides type was the most abundant with a total of 148,717 spores, followed by [i]Leptosphaeria, Coprinus[/i] and the [i]Aspergillus-Penicillium [/i]type spores, all of them with total values ranging from 20,591 – 16,392 spores. The higher monthly concentrations were registered in January (31,663 spores and the lowest in December (7,314 spores. Generally, the average quantity of spores recorded during the months of the dry season (20,599 spores was higher compared with that observed during the rainy season (17,460 spores.

  16. Thirty-four identifiable airborne fungal spores in Havana, Cuba

    Directory of Open Access Journals (Sweden)

    Michel Almaguer

    2015-05-01

    Full Text Available The airborne fungal spore content in Havana, Cuba, collected by means a non-viable volumetric methodology, was studied from November 2010 – October 2011. The study, from a qualitative point of view, allowed the characterization of 29 genera and 5 fungal types, described following the Saccardo´s morphotypes, as well as their morphobiometrical characteristics. In the amerospores morphotype, the conidia of 7 genera (with ascospores, basidiospores and uredospores and 5 fungal types were included. Among phragmospores morphotype, the ascospores and conidia of 12 different genera were identified. The dictyospores morphotype only included conidial forms from 6 genera. Finally, the less frequent morphotypes were staurospores, didymospores and distosepted spores. In general, the main worldwide spread mitosporic fungi also predominated in the Havana atmosphere, accompanied by some ascospores and basidiospores. Cladosporium cladosporioides type was the most abundant with a total of 148,717 spores, followed by Leptosphaeria, Coprinus and the Aspergillus-Penicillium type spores, all of them with total values ranging from 20,591 – 16,392 spores. The higher monthly concentrations were registered in January (31,663 spores and the lowest in December (7,314 spores. Generally, the average quantity of spores recorded during the months of the dry season (20,599 spores was higher compared with that observed during the rainy season (17,460 spores.

  17. Thirty-four identifiable airborne fungal spores in Havana, Cuba.

    Science.gov (United States)

    Almaguer, Michel; Aira, María-Jesús; Rodríguez-Rajo, F Javier; Fernandez-Gonzalez, Maria; Rojas-Flores, Teresa I

    2015-01-01

    The airborne fungal spore content in Havana, Cuba, collected by means a non-viable volumetric methodology, was studied from November 2010 - October 2011. The study, from a qualitative point of view, allowed the characterization of 29 genera and 5 fungal types, described following the Saccardo´s morphotypes, as well as their morphobiometrical characteristics. In the amerospores morphotype, the conidia of 7 genera (with ascospores, basidiospores and uredospores) and 5 fungal types were included. Among phragmospores morphotype, the ascospores and conidia of 12 different genera were identified. The dictyospores morphotype only included conidial forms from 6 genera. Finally, the less frequent morphotypes were staurospores, didymospores and distosepted spores. In general, the main worldwide spread mitosporic fungi also predominated in the Havana atmosphere, accompanied by some ascospores and basidiospores. Cladosporium cladosporioides type was the most abundant with a total of 148,717 spores, followed by Leptosphaeria, Coprinus and the Aspergillus-Penicillium type spores, all of them with total values ranging from 20,591 - 16,392 spores. The higher monthly concentrations were registered in January (31,663 spores) and the lowest in December (7,314 spores). Generally, the average quantity of spores recorded during the months of the dry season (20,599 spores) was higher compared with that observed during the rainy season (17,460 spores).

  18. Airborne Spore Analysis of Karabük Atmosphere

    Directory of Open Access Journals (Sweden)

    Ayşe Kaplan

    2014-05-01

    Full Text Available In order to identify types and amounts of airborne allergenic spore dispersal in the atmosphere of Karabük by gravimetric method in 2006 and 2007, two Durham samplers were situated on roof and garden of Technical Education Faculty of Karabük University between the dates January 1, 2006 and December 31, 2007. As a result of the analysis a total of 2822.2±625.01 spore/cm2 spore quantity belonging to 21 types was identified. Of this total, 1106±250.33 spore/cm² was observed in 2006 and 1716±374.68 spore/cm² was observed in 2007. Spore concentrations revealed no statistically differences between two samplers (t=0.1527-1.1355, p>0.05. The relationship between spore concentrations and meteorological factors was displayed by Spearman Correlation analysis. The highest quantity of fungal spores and Myxomycetes were determined in June and July. Cladosporium, Alternaria, Ustilago, Myxomycetes and unidentified Ascomycetes spores were recorded as dominant. In the end of this study, a two-year spore calendar was prepared.

  19. Killing of Bacillus Megaterium Spores by X-rays at the Phosphorus K-edge

    Science.gov (United States)

    Richmond, Robert C.; Frigo, Sean P.; Ehret, Charles F.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    This study continues a progression of experiments on the radiation-induced killing of bacterial spores that began at the Argonne National Laboratory in 1957. A series of aliquots of Bacillus megaterium spores were prepared onto polycarbonate filters and irradiated with photons of 2159 eV compared to 2140 eV energy on the 2-IDB beamline at the Advanced Photon Source. Flux density was approximately 10(exp 18) photons/sec/sq mm. The phosphorous K-edge absorption spectrum in these spores was determined to peak at 2159 eV, wheras 2140 eV was determined to be outside that absorption spectrum. Spores on filters were irradiated at ambient conditions, and were either immediately plated for colony formation after irradiation, or were held for postirradiation exposure to oxygen prior to plating. Slopes of survival curves from the four conditions of irradiation, i.e., two photon energies each comparing immediate plating vs postirradiation holding, were used for quantitative determination of differences in rates of spore killing over a range of radiation doses. It was found that spores irradiated at the phosphorus K-edge were killed 20% more efficiently than when irradiated with 2140 eV photons, and this was true for both immediate plating and postirradiation holding in air. Postirradiation holding in air increased killing efficiency by about 12% for both photon energies compared to plating immediately after irradiation. The increase of killing efficiency with postirradiation holding is less than expected from earlier experiments using relatively low-flux X-rays, and raises the possibility of dose-mitigation by radical-radical recombination in the case of high-flux X-rays from the synchrotron.

  20. Kinetics of Mn(II) oxidation by spores of the marine Bacillus sp. SG-1

    Science.gov (United States)

    Toyoda, Kazuhiro; Tebo, Bradley M.

    2016-09-01

    The kinetics of Mn(II) oxidation by spores of the marine Bacillus sp. SG-1 was measured under controlled conditions of the initial Mn(II) concentration, spore concentration, chemical speciation, pH, O2, and temperature. Mn(II) oxidation experiments were performed with spore concentrations ranging from 0.7 to 11 × 109 spores/L, a pH range from 5.8 to 8.1, temperatures between 4 and 58 °C, a range of dissolved oxygen from 2 to 270 μM, and initial Mn(II) concentrations from 1 to 200 μM. The Mn(II) oxidation rates were directly proportional to the spore concentrations over these ranges of concentration. The Mn(II) oxidation rate increased with increasing initial Mn(II) concentration to a critical concentration, as described by the Michaelis-Menten model (Km = ca. 3 μM). Whereas with starting Mn(II) concentrations above the critical concentration, the rate was almost constant in low ionic solution (I = 0.05, 0.08). At high ionic solution (I = 0.53, 0.68), the rate was inversely correlated with Mn(II) concentration. Increase in the Mn(II) oxidation rate with the dissolved oxygen concentration followed the Michaelis-Menten model (Km = 12-19 μM DO) in both a HEPES-buffered commercial drinking (soft) water and in artificial and natural seawater. Overall, our results suggest that the mass transport limitations of Mn(II) ions due to secondary Mn oxide products accumulating on the spores cause a significant decrease of the oxidation rate at higher initial Mn(II) concentration on a spore basis, as well as in more concentrated ionic solutions. The optimum pH for Mn(II) oxidation was approximately 7.0 in low ionic solutions (I = 0.08). The high rates at the alkaline side (pH > 7.5) may suggest a contribution by heterogeneous reactions on manganese bio-oxides. The effect of temperature on the Mn(II) oxidation rate was studied in three solutions (500 mM NaCl, ASW, NSW solutions). Thermal denaturation occurred at 58 °C and spore germination was evident at 40 °C in all three

  1. Aerobic deterioration stimulates outgrowth of spore-forming Paenibacillus in corn silage stored under oxygen-barrier or polyethylene films.

    Science.gov (United States)

    Borreani, Giorgio; Dolci, Paola; Tabacco, Ernesto; Cocolin, Luca

    2013-08-01

    The occurrence of Bacillus and Paenibacillus spores in silage is of great concern to dairy producers because their spores can survive pasteurization and some strains are capable of subsequently germinating and growing under refrigerated conditions in pasteurized milk. The objectives of this study were to verify the role of aerobic deterioration of corn silage on the proliferation of Paenibacillus spores and to evaluate the efficacy of oxygen-barrier films used to cover silage during fermentation and storage to mitigate these undesirable bacterial outbreaks. The trial was carried out on whole-crop maize (Zea mays L.) inoculated with a mixture of Lactobacillus buchneri, Lactobacillus plantarum, and Enterococcus faecium. A standard polyethylene film and a polyethylene-polyamide film with an enhanced oxygen barrier were used to produce the silage bags for this experiment. The silos were stored indoors at ambient temperature (18 to 22°C) and opened after 110 d. The silage was sampled after 0, 2, 5, 7, 9, and 14 d of aerobic exposure to quantify the growth of endospore-forming bacteria during the exposure of silages to air. Paenibacillus macerans (gram-positive, facultatively anaerobic bacteria) was able to develop during the aerobic exposure of corn silage. This species was present in the herbage at harvesting, together with clostridial spores, and survived ensiling fermentation; it constituted more than 60% of the anaerobic spore formers at silage opening. During silage spoilage, the spore concentration of P. macerans increased to values greater than 7.0 log10 cfu/g of silage. The use of different plastic films to seal silages affected the growth of P. macerans and the number of spores during aerobic exposure of silages. These results indicate that the number of Paenibacillus spores could greatly increase in silage after exposure to air, and that oxygen-barrier films could help to reduce the potential for silage contamination of this important group of milk spoilage

  2. A study of Ganoderma lucidum spores by FTIR microspectroscopy

    Science.gov (United States)

    Wang, Xin; Chen, Xianliang; Qi, Zeming; Liu, Xingcun; Li, Weizu; Wang, Shengyi

    2012-06-01

    In order to obtain unique information of Ganoderma lucidum spores, FTIR microspectroscopy was used to study G. lucidum spores from Anhui Province (A), Liaoning Province (B) and Shangdong Province (C) of China. IR micro-spectra were acquired with high-resolution and well-reproducibility. The IR spectra of G. lucidum spores from different areas were similar and mainly made up of the absorption bands of polysaccharide, sterols, proteins, fatty acids, etc. The results of curve fitting indicated the protein secondary structures were dissimilar among the above G. lucidum spores. To identify G. lucidum spores from different areas, the H1078/H1640 value might be a potentially useful factor, furthermore FTIR microspectroscopy could realize this identification efficiently with the help of hierarchical cluster analysis. The result indicates FTIR microspectroscopy is an efficient tool for identification of G. lucidum spores from different areas. The result also suggests FTIR microspectroscopy is a potentially useful tool for the study of TCM.

  3. The infrared spectral transmittance of Aspergillus niger spore aggregated particle swarm

    Science.gov (United States)

    Zhao, Xinying; Hu, Yihua; Gu, Youlin; Li, Le

    2015-10-01

    Microorganism aggregated particle swarm, which is quite an important composition of complex media environment, can be developed as a new kind of infrared functional materials. Current researches mainly focus on the optical properties of single microorganism particle. As for the swarm, especially the microorganism aggregated particle swarm, a more accurate simulation model should be proposed to calculate its extinction effect. At the same time, certain parameters deserve to be discussed, which helps to better develop the microorganism aggregated particle swarm as a new kind of infrared functional materials. In this paper, take Aspergillus Niger spore as an example. On the one hand, a new calculation model is established. Firstly, the cluster-cluster aggregation (CCA) model is used to simulate the structure of Aspergillus Niger spore aggregated particle. Secondly, the single scattering extinction parameters for Aspergillus Niger spore aggregated particle are calculated by using the discrete dipole approximation (DDA) method. Thirdly, the transmittance of Aspergillus Niger spore aggregated particle swarm is simulated by using Monte Carlo method. On the other hand, based on the model proposed above, what influences can wavelength causes has been studied, including the spectral distribution of scattering intensity of Aspergillus Niger spore aggregated particle and the infrared spectral transmittance of the aggregated particle swarm within the range of 8~14μm incident infrared wavelengths. Numerical results indicate that the scattering intensity of Aspergillus Niger spore aggregated particle reduces with the increase of incident wavelengths at each scattering angle. Scattering energy mainly concentrates on the scattering angle between 0~40°, forward scattering has an obvious effect. In addition, the infrared transmittance of Aspergillus Niger spore aggregated particle swarm goes up with the increase of incident wavelengths. However, some turning points of the trend

  4. Inactivation of Bacillus spores inoculated in milk by Ultra High Pressure Homogenization.

    Science.gov (United States)

    Amador Espejo, Genaro Gustavo; Hernández-Herrero, M M; Juan, B; Trujillo, A J

    2014-12-01

    Ultra High-Pressure Homogenization treatments at 300 MPa with inlet temperatures (Ti) of 55, 65, 75 and 85 °C were applied to commercial Ultra High Temperature treated whole milk inoculated with Bacillus cereus, Bacillus licheniformis, Bacillus sporothermodurans, Bacillus coagulans, Geobacillus stearothermophilus and Bacillus subtilis spores in order to evaluate the inactivation level achieved. Ultra High-Pressure Homogenization conditions at 300 MPa with Ti = 75 and 85 °C were capable of a spore inactivation of ∼5 log CFU/mL. Furthermore, under these processing conditions, commercial sterility (evaluated as the complete inactivation of the inoculated spores) was obtained in milk, with the exception of G. stearothermophilus and B. subtilis treated at 300 MPa with Ti = 75 °C. The results showed that G. stearothermophilus and B. subtilis have higher resistance to the Ultra High-Pressure Homogenization treatments applied than the other microorganisms inoculated and that a treatment performed at 300 MPa with Ti = 85 °C was necessary to completely inactivate these microorganisms at the spore level inoculated (∼1 × 10(6) CFU/mL). Besides, a change in the resistance of B. licheniformis, B. sporothermodurans, G. stearothermophilus and B. subtilis spores was observed as the inactivation obtained increased remarkably in treatments performed with Ti between 65 and 75 °C. This study provides important evidence of the suitability of UHPH technology for the inactivation of spores in high numbers, leading to the possibility of obtaining commercially sterile milk.

  5. Biocidal Energetic Materials for the Destruction of Spore Forming Bacteria

    Science.gov (United States)

    2015-07-01

    L R E P O R T DTRA-TR-13-52 Biocidal Energetic Materials for the Destruction of Spore Forming Bacteria Distribution Statement A...Z39.18 00-07-2015 Technical N/A Biocidal Energetic Materials for the Destruction of Spore Forming Bacteria HDTRA1-10-1-0108 Emily M. Hunt, Ph.D. West...understand the interaction between spore forming bacteria and thermite reactions and products and to exploit energetic material reactions with

  6. The Molecular Timeline of a Reviving Bacterial Spore

    OpenAIRE

    2015-01-01

    Summary The bacterial spore can rapidly convert from a dormant to a fully active cell. Here we study this remarkable cellular transition in Bacillus subtilis and reveal the identity of the newly synthesized proteins throughout spore revival. Our analysis uncovers a highly ordered developmental program that correlates with the spore morphological changes and reveals the spatial and temporal molecular events fundamental to reconstruct a cell. As opposed to current knowledge, we found that trans...

  7. Spore Coat Architecture of Clostridium novyi NT Spores▿

    OpenAIRE

    Plomp, Marco; McCaffery, J. Michael; Cheong, Ian; Huang, Xin; Bettegowda, Chetan; Kinzler, Kenneth W.; Zhou, Shibin; Vogelstein, Bert; Malkin, Alexander J.

    2007-01-01

    Spores of the anaerobic bacterium Clostridium novyi NT are able to germinate in and destroy hypoxic regions of tumors in experimental animals. Future progress in this area will benefit from a better understanding of the germination and outgrowth processes that are essential for the tumorilytic properties of these spores. Toward this end, we have used both transmission electron microscopy and atomic force microscopy to determine the structure of both dormant and germinating spores. We found th...

  8. Inactivation of Bacillus Anthracis Spores Using Carbon Nanotubes

    Science.gov (United States)

    2014-10-30

    the attachment of B. anthracis spores, when in combination with natural peptide nisin, it can inhibit the biofilm formation from B. anthrancis spores...McCoy, Chang Yang, Wei Chen, Ebenezer Addae, Liju Yang. Investigation of Gold/ Copper Sulfide Core/Shell Nanoparticles’ Antimicrobial Activity to...1. “Effect of Gold/ Copper Sulfide Core/Shell Nanoparticles on Bacillus Anthracis Spores and Cells”, E. Addae1, M. Lilly1, E. McCoy1, C. Yang2, W

  9. Functional and Immunological Analyses of Superoxide Dismutases and Other Spore-Associated Proteins of Bacillus anthracis

    Science.gov (United States)

    2008-08-20

    exposed spore proteins by ELISA . ..69 Figure 6. Localization of B. anthracis spore proteins within the spore by immunoelectron microscopy...Staphylococcus aureus (114), Streptococcus agalactiae (177), Bordatella pertussis (119), Shigella flexneri (73), Campylobacter jejuni (178), and Enterococcus... ELISA analysis. Anti-spore ELISA . Analysis of antigen target accessibility on the spore surface was done by enzyme-linked immunosorbent assays

  10. Chitinolytic activity in viable spores of encephalitozoon species

    Directory of Open Access Journals (Sweden)

    Schottelius J

    2000-01-01

    Full Text Available By employing 4-methylumbelliferyl-beta-D-NN',N"-triacetylchitotriose substrate in a semi quantitative assay, chitinolytic activity in viable spores of Encephalitozoon cuniculi and E. intestinalis was detected and dependence on reaction time, spore concentration, concentration of substrate and temperature were demonstrated. It was possible to block the chitinolytic activity by chitin hydrolysate. By incubation at 80°C for 10 min or at 55°C for 20 min the spores were loosing the chitinolytic activity. Incubation of the spores in trypsin reduced the chitinolytic activity. Cellulase activity could not be detected.

  11. Surface tension propulsion of fungal spores by use of microdroplets

    CERN Document Server

    Noblin, Xavier; Dumais, Jacques

    2010-01-01

    Many edible mushrooms eject their spores (about 10 microns in size) at high speed (about 1 m/s) using surface tension forces in a few microseconds. Basically the coalescence of a droplet with the spore generates the necessary momentum to eject the spore. We have detailed this mechanism in \\cite{noblin2}. In this article, we give some details about the high speed movies (up to 250000 fps) of mushrooms' spores ejection attached to this submission. This video was submitted as part of the Gallery of Fluid Motion 2010 which is showcase of fluid dynamics videos.

  12. Quantitative and Sensitive RNA Based Detection of Bacillus Spores

    Directory of Open Access Journals (Sweden)

    Ekaterina eOsmekhina

    2014-03-01

    Full Text Available The fast and reliable detection of bacterial spores is of great importance and still remains a challenge. Here we describe a direct RNA based diagnostic method for the specific detection of viable bacterial spores which does not depends on an enzymatic amplification step and therefore is directly appropriate for quantification. The procedure includes the following steps: (i heat activation of spores, (ii germination and enrichment cultivation, (iii cell lysis, and (iv analysis of 16S rRNA in crude cell lysates using a sandwich hybridization assay. The sensitivity of the method is dependent on the cultivation time and the detection limit; it is possible to detect 10 spores per ml when the RNA analysis is performed after 6 h of enrichment cultivation. At spore concentrations above 106 spores per ml the cultivation time can be shortened to 30 min. Total analysis times are in the range of 2 to 8 hours depending on the spore concentration in samples. The developed procedure is optimized at the example of Bacillus subtilis spores but should be applicable to other organisms. The new method can easily be modified for other target RNAs and is suitable for specific detection of spores from known groups of organisms.

  13. A bacterial spore model of pulsed electric fields on spore morphology change revealed by simulation and SEM.

    Science.gov (United States)

    Qiu, Xing; Lee, Yin Tung; Yung, Pun To

    2014-01-01

    A two-layered spore model was proposed to analyze morphological change of bacterial spores subjected under pulsed electric fields. The outer layer, i.e. spore coat, was defined by Mooney-Rivlin hyper-elastic material model. The inner layer, i.e. peptidoglycan and spore core, was modeled by applying additional adhesion forces. The effect of pulsed electric fields on surface displacement was simulated in COMSOL Multiphysics and verified by SEM. The electro-mechanical theory, considering spore coat as a capacitor, was used to explain concavity; and the thin viscoelastic film theory, considering membrane bilayer as fluctuating surfaces, was used to explain leakage forming. Mutual interaction of external electric fields, charged spores, adhesion forces and ions movement were all predicted to contribute to concavity and leakage.

  14. A novel small acid soluble protein variant is important for spore resistance of most Clostridium perfringens food poisoning isolates.

    Directory of Open Access Journals (Sweden)

    Jihong Li

    2008-05-01

    Full Text Available Clostridium perfringens is a major cause of food poisoning (FP in developed countries. C. perfringens isolates usually induce the gastrointestinal symptoms of this FP by producing an enterotoxin that is encoded by a chromosomal (cpe gene. Those typical FP strains also produce spores that are extremely resistant to food preservation approaches such as heating and chemical preservatives. This resistance favors their survival and subsequent germination in improperly cooked, prepared, or stored foods. The current study identified a novel alpha/beta-type small acid soluble protein, now named Ssp4, and showed that sporulating cultures of FP isolates producing resistant spores consistently express a variant Ssp4 with an Asp substitution at residue 36. In contrast, Gly was detected at Ssp4 residue 36 in C. perfringens strains producing sensitive spores. Studies with isogenic mutants and complementing strains demonstrated the importance of the Asp 36 Ssp4 variant for the exceptional heat and sodium nitrite resistance of spores made by most FP strains carrying a chromosomal cpe gene. Electrophoretic mobility shift assays and DNA binding studies showed that Ssp4 variants with an Asp at residue 36 bind more efficiently and tightly to DNA than do Ssp4 variants with Gly at residue 36. Besides suggesting one possible mechanistic explanation for the highly resistant spore phenotype of most FP strains carrying a chromosomal cpe gene, these findings may facilitate eventual development of targeted strategies to increase killing of the resistant spores in foods. They also provide the first indication that SASP variants can be important contributors to intra-species (and perhaps inter-species variations in bacterial spore resistance phenotypes. Finally, Ssp4 may contribute to spore resistance properties throughout the genus Clostridium since ssp4 genes also exist in the genomes of other clostridial species.

  15. A novel small acid soluble protein variant is important for spore resistance of most Clostridium perfringens food poisoning isolates.

    Science.gov (United States)

    Li, Jihong; McClane, Bruce A

    2008-05-02

    Clostridium perfringens is a major cause of food poisoning (FP) in developed countries. C. perfringens isolates usually induce the gastrointestinal symptoms of this FP by producing an enterotoxin that is encoded by a chromosomal (cpe) gene. Those typical FP strains also produce spores that are extremely resistant to food preservation approaches such as heating and chemical preservatives. This resistance favors their survival and subsequent germination in improperly cooked, prepared, or stored foods. The current study identified a novel alpha/beta-type small acid soluble protein, now named Ssp4, and showed that sporulating cultures of FP isolates producing resistant spores consistently express a variant Ssp4 with an Asp substitution at residue 36. In contrast, Gly was detected at Ssp4 residue 36 in C. perfringens strains producing sensitive spores. Studies with isogenic mutants and complementing strains demonstrated the importance of the Asp 36 Ssp4 variant for the exceptional heat and sodium nitrite resistance of spores made by most FP strains carrying a chromosomal cpe gene. Electrophoretic mobility shift assays and DNA binding studies showed that Ssp4 variants with an Asp at residue 36 bind more efficiently and tightly to DNA than do Ssp4 variants with Gly at residue 36. Besides suggesting one possible mechanistic explanation for the highly resistant spore phenotype of most FP strains carrying a chromosomal cpe gene, these findings may facilitate eventual development of targeted strategies to increase killing of the resistant spores in foods. They also provide the first indication that SASP variants can be important contributors to intra-species (and perhaps inter-species) variations in bacterial spore resistance phenotypes. Finally, Ssp4 may contribute to spore resistance properties throughout the genus Clostridium since ssp4 genes also exist in the genomes of other clostridial species.

  16. Characterization of aerobic spore-forming bacteria associated with industrial dairy processing environments and product spoilage.

    Science.gov (United States)

    Lücking, Genia; Stoeckel, Marina; Atamer, Zeynep; Hinrichs, Jörg; Ehling-Schulz, Monika

    2013-09-02

    Due to changes in the design of industrial food processing and increasing international trade, highly thermoresistant spore-forming bacteria are an emerging problem in food production. Minimally processed foods and products with extended shelf life, such as milk products, are at special risk for contamination and subsequent product damages, but information about origin and food quality related properties of highly heat-resistant spore-formers is still limited. Therefore, the aim of this study was to determine the biodiversity, heat resistance, and food quality and safety affecting characteristics of aerobic spore-formers in the dairy sector. Thus, a comprehensive panel of strains (n=467), which originated from dairy processing environments, raw materials and processed foods, was compiled. The set included isolates associated with recent food spoilage cases and product damages as well as isolates not linked to product spoilage. Identification of the isolates by means of Fourier-transform infrared spectroscopy and molecular methods revealed a large biodiversity of spore-formers, especially among the spoilage associated isolates. These could be assigned to 43 species, representing 11 genera, with Bacillus cereus s.l. and Bacillus licheniformis being predominant. A screening for isolates forming thermoresistant spores (TRS, surviving 100°C, 20 min) showed that about one third of the tested spore-formers was heat-resistant, with Bacillus subtilis and Geobacillus stearothermophilus being the prevalent species. Strains producing highly thermoresistant spores (HTRS, surviving 125°C, 30 min) were found among mesophilic as well as among thermophilic species. B. subtilis and Bacillus amyloliquefaciens were dominating the group of mesophilic HTRS, while Bacillus smithii and Geobacillus pallidus were dominating the group of thermophilic HTRS. Analysis of spoilage-related enzymes of the TRS isolates showed that mesophilic strains, belonging to the B. subtilis and B. cereus

  17. Effects of Ohmic Heating, Including Electric Field Intensity and Frequency, on Thermal Inactivation of Bacillus subtilis Spores.

    Science.gov (United States)

    Murashita, Suguru; Kawamura, Shuso; Koseki, Shigenobu

    2017-01-01

    Methods for microbial inactivation are important in the food industry; however, conventional external heating (CH) reduces food quality. Accordingly, the nonthermal effects of ohmic heating (OH) on Bacillus subtilis spores in a sodium chloride aqueous solution at 101°C (i.e., the boiling point), as well as the effects of electric field intensity and frequency during OH, were investigated. Survival kinetics were compared between OH and external CH. The inactivation effect on B. subtilis was greater for all electric field conditions (5, 10, and 20 V/cm) than for CH. In particular, 20 V/cm showed a significantly higher inactivation effect (P 0.05) in survival kinetics between 20, 40, and 60 kHz; B. subtilis spores were inactivated more efficiently as the frequency increased. B. subtilis spores were almost completely inactivated at 14 to 16 min for the 60-kHz treatment, but spores were still alive at 20 and 40 kHz for the same treatment times. These results demonstrated that OH inactivates B. subtilis spores more effectively than CH. OH conditions with high electric field intensities and high frequencies resulted in efficient B. subtilis spore inactivation.

  18. Analysis of a Novel Spore Antigen in Bacillus anthracis That Contributes to Spore Opsonization

    Science.gov (United States)

    2008-01-01

    sporulated by culture in Leighton–Doi broth with spectinomycin, and the spores were harvested and purified as described above. Single colonies of the...percentage recovery was calculated by determining the percentage of mutant bacteria (based upon antibiotic resistance) recovered from the spleen... Fermentation , purification, and characterization of protective antigen from a recombinant, avirulent strain of Bacillus anthracis. Appl Environ

  19. Contamination of healthcare workers' hands with bacterial spores.

    Science.gov (United States)

    Sasahara, Teppei; Ae, Ryusuke; Watanabe, Michiyo; Kimura, Yumiko; Yonekawa, Chikara; Hayashi, Shunji; Morisawa, Yuji

    2016-08-01

    Clostridium species and Bacillus spp. are spore-forming bacteria that cause hospital infections. The spores from these bacteria are transmitted from patient to patient via healthcare workers' hands. Although alcohol-based hand rubbing is an important hand hygiene practice, it is ineffective against bacterial spores. Therefore, healthcare workers should wash their hands with soap when they are contaminated with spores. However, the extent of health care worker hand contamination remains unclear. The aim of this study is to determine the level of bacterial spore contamination on healthcare workers' hands. The hands of 71 healthcare workers were evaluated for bacterial spore contamination. Spores attached to subject's hands were quantitatively examined after 9 working hours. The relationship between bacterial spore contamination and hand hygiene behaviors was also analyzed. Bacterial spores were detected on the hands of 54 subjects (76.1%). The mean number of spores detected was 468.3 CFU/hand (maximum: 3300 CFU/hand). Thirty-seven (52.1%) and 36 (50.7%) subjects were contaminated with Bacillus subtilis and Bacillus cereus, respectively. Nineteen subjects (26.8%) were contaminated with both Bacillus species. Clostridium difficile was detected on only one subject's hands. There was a significant negative correlation between the hand contamination level and the frequency of handwashing (r = -0.44, P < 0.01) and a significant positive correlation between the hand contamination level and the elapsed time since last handwashing (r = 0.34, P < 0.01). Healthcare workers' hands may be frequently contaminated with bacterial spores due to insufficient handwashing during daily patient care.

  20. Model simulations of fungal spore distribution over the Indian region

    Science.gov (United States)

    Ansari, Tabish U.; Valsan, Aswathy E.; Ojha, N.; Ravikrishna, R.; Narasimhan, Balaji; Gunthe, Sachin S.

    2015-12-01

    Fungal spores play important role in the health of humans, animals, and plants by constituting a class of the primary biological aerosol particles (PBAPs). Additionally, these could mediate the hydrological cycle by acting as nuclei for ice and cloud formation (IN and CCN respectively). Various processes in the biosphere and the variations in the meteorological conditions control the releasing mechanism of spores through active wet and dry discharge. In the present paper, we simulate the concentration of fungal spores over the Indian region during three distinct meteorological seasons by combining a numerical model (WRF-Chem) with the fungal spore emissions based on land-use type. Maiden high-resolution regional simulations revealed large spatial gradient and strong seasonal dependence in the concentration of fungal spores over the Indian region. The fungal spore concentrations are found to be the highest during winter (0-70 μg m-3 in December), moderately higher during summer (0-35 μg m-3 in May) and lowest during the monsoon (0-25 μg m-3 in July). The elevated concentrations during winter are attributed to the shallower boundary layer trapping the emitted fungal spores in smaller volume. In contrast, the deeper boundary layer mixing in May and stronger monsoonal-convection in July distribute the fungal spores throughout the lower troposphere (∼5 km). We suggest that the higher fungal spore concentrations during winter could have potential health impacts. While, stronger vertical mixing could enable fungal spores to influence the cloud formation during summer and monsoon. Our study provides the first information about the distribution and seasonal variation of fungal spores over the densely populated and observationally sparse Indian region.

  1. Warm and dry weather accelerates and elongates Cladosporium spore seasons in Poland.

    Science.gov (United States)

    Kasprzyk, Idalia; Kaszewski, Boguslaw Michal; Weryszko-Chmielewska, Elzbieta; Nowak, Malgorzata; Sulborska, Aneta; Kaczmarek, Joanna; Szymanska, Agata; Haratym, Weronika; Jedryczka, Malgorzata

    Temperature is the environmental factor that systematically changes for decades and, as in plants and animals, can significantly affect the growth and development of fungi, including the abundance of their sporulation. During the time of study (2010-2012), a rapid increase in air temperature was observed in Poland, which coincided with the substantial decrease in rainfall. The increase in annual mean temperatures at three monitoring sites of this study was 0.9 °C in Lublin and Rzeszow (east Poland) and 2.0 °C in Poznan (west Poland). Such warming of air masses was comparable to the average global air temperature rise in the period of 1880-2012 accounting for 0.85 °C, as reported by the Intergovernmental Panel on Climate Change. Moreover, there was a substantial decrease in rainfall, ranging from 32.7 % (Poznan) to 43.0 % (Rzeszow). We have demonstrated that under such conditions the mean and median values of total Cladosporium spore counts significantly increased and the spore seasons were greatly accelerated. Moreover, earlier start and later end of the season caused its extension, lasting from over 20 days in Rzeszow to around 60 days in Lublin and Poznan, when the cumulative amount of 5-95 % of spores was considered. The time of reaching the cumulative amount of 50 % of spores was up to 25 days earlier (difference in Poznan between 2010 and 2012). There was also a striking acceleration of the date of the maximal Cladosporium spore concentration per cubic metre of air (26 days for Lublin, 43 for Poznan and 56 for Rzeszow).

  2. Analysis of the Raman spectra of Ca(2+)-dipicolinic acid alone and in the bacterial spore core in both aqueous and dehydrated environments.

    Science.gov (United States)

    Kong, Lingbo; Setlow, Peter; Li, Yong-qing

    2012-08-21

    The core of dormant bacterial spores suspended in water contains a large depot of dipicolinic acid (DPA) chelated with divalent cations, predominantly Ca(2+) (CaDPA), and surrounded by water molecules. Since the intensities of the vibration bands of CaDPA molecules depend significantly on the water content in the CaDPA's environment, the Raman spectra of CaDPA in spores may allow the determination of the spore core's hydration state. We have measured Raman spectra of single spores of three Bacillus species in different hydration states including the spores suspended in water, air-dried and vacuum-dried. As a comparison, we also measured the Raman spectra of CaDPA and DPA in different forms including in aqueous solution, and as amorphous powder and crystalline form. We also monitored changes in Raman spectra of an individual spore during dehydration under vacuum. The results indicated that (1) the state of CaDPA in the core of a spore suspended in water is close to an amorphous solid or a glassy state, but still mixed with water molecules; (2) the ratio of intensities of Raman bands at 1575 and 1017 cm(-1) (I(1575)/I(1017)) is sensitive to the water content in the CaDPA's environment; (3) variations in I(1575)/I(1017) are small (∼4%) in a population of dormant Bacillus spores suspended in water; and (4) the I(1575)/I(1017) ratio increases significantly during dehydration under vacuum. Consequently, measurement of the I(1575)/I(1017) ratio of CaDPA in spores may allow a qualitative estimation of the degree of hydration of the bacterial spore's core.

  3. Live-imaging of Bacillus subtilis spore germination and outgrowth

    NARCIS (Netherlands)

    Pandey, R.

    2014-01-01

    Spores of Gram-positive bacteria such as Bacillus and Clostridium cause huge economic losses to the food industry. In food products, spores survive under food preservation conditions and subsequent germination and outgrowth eventually causes food spoilage. Therefore efforts are being made to elimina

  4. Binding Affinity of Glycoconjugates to BACILLUS Spores and Toxins

    Science.gov (United States)

    Rasol, Aveen; Eassa, Souzan; Tarasenko, Olga

    2010-04-01

    Early recognition of Bacillus cereus group species is important since they can cause food-borne illnesses and deadly diseases in humans. Glycoconjugates (GCs) are carbohydrates covalently linked to non-sugar moieties including lipids, proteins or other entities. GCs are involved in recognition and signaling processes intrinsic to biochemical functions in cells. They also stimulate cell-cell adhesion and subsequent recognition and activation of receptors. We have demonstrated that GCs are involved in Bacillus cereus spore recognition. In the present study, we have investigated whether GCs possess the ability to bind and recognize B. cereus spores and Bacillus anthracis recombinant single toxins (sTX) and complex toxins (cTX). The affinity of GCs to spores + sTX and spores + cTX toxins was studied in the binding essay. Our results demonstrated that GC9 and GC10 were able to selectively bind to B. cereus spores and B. anthracis toxins. Different binding affinities for GCs were found toward Bacillus cereus spores + sTX and spores + cTX. Dilution of GCs does not impede the recognition and binding. Developed method provides a tool for simultaneous recognition and targeting of spores, bacteria toxins, and/or other entities.

  5. Mushrooms as Rainmakers: How Spores Act as Nuclei for Raindrops.

    Science.gov (United States)

    Hassett, Maribeth O; Fischer, Mark W F; Money, Nicholas P

    2015-01-01

    Millions of tons of fungal spores are dispersed in the atmosphere every year. These living cells, along with plant spores and pollen grains, may act as nuclei for condensation of water in clouds. Basidiospores released by mushrooms form a significant proportion of these aerosols, particularly above tropical forests. Mushroom spores are discharged from gills by the rapid displacement of a droplet of fluid on the cell surface. This droplet is formed by the condensation of water on the spore surface stimulated by the secretion of mannitol and other hygroscopic sugars. This fluid is carried with the spore during discharge, but evaporates once the spore is airborne. Using environmental electron microscopy, we have demonstrated that droplets reform on spores in humid air. The kinetics of this process suggest that basidiospores are especially effective as nuclei for the formation of large water drops in clouds. Through this mechanism, mushroom spores may promote rainfall in ecosystems that support large populations of ectomycorrhizal and saprotrophic basidiomycetes. Our research heightens interest in the global significance of the fungi and raises additional concerns about the sustainability of forests that depend on heavy precipitation.

  6. High resolution FESEM and TEM reveal bacterial spore attachment.

    Science.gov (United States)

    Panessa-Warren, Barbara J; Tortora, George T; Warren, John B

    2007-08-01

    Transmission electron microscopy (TEM) studies in the 1960s and early 1970s using conventional thin section and freeze fracture methodologies revealed ultrastructural bacterial spore appendages. However, the limited technology at that time necessitated the time-consuming process of imaging serial sections and reconstructing each structure. Consequently, the distribution and function of these appendages and their possible role in colonization or pathogenesis remained unknown. By combining high resolution field emission electron microscopy with TEM images of identical bacterial spore preparations, we have been able to obtain images of intact and sectioned Bacillus and Clostridial spores to clearly visualize the appearance, distribution, resistance (to trypsin, chloramphenicol, and heat), and participation of these structures to facilitate attachment of the spores to glass, agar, and human cell substrates. Current user-friendly commercial field emission scanning electron microscopes (FESEMs), permit high resolution imaging, with high brightness guns at lower accelerating voltages for beam sensitive intact biological samples, providing surface images at TEM magnifications for making direct comparisons. For the first time, attachment structures used by pathogenic, environmental, and thermophile bacterial spores could be readily visualized on intact spores to reveal how specific appendages and outer spore coats participated in spore attachment, colonization, and invasion.

  7. Bacillus atrophaeus Outer Spore Coat Assembly and Ultrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; Leighton, T J; Wheeler, K E; Pitesky, M E; Malkin, A J

    2005-11-21

    Our previous atomic force microscopy (AFM) studies successfully visualized native Bacillus atrophaeus spore coat ultrastructure and surface morphology. We have shown that the outer spore coat surface is formed by a crystalline array of {approx}11 nm thick rodlets, having a periodicity of {approx}8 nm. We present here further AFM ultrastructural investigations of air-dried and fully hydrated spore surface architecture. In the rodlet layer, planar and point defects, as well as domain boundaries, similar to those described for inorganic and macromolecular crystals, were identified. For several Bacillus species, rodlet structure assembly and architectural variation appear to be a consequence of species-specific nucleation and crystallization mechanisms that regulate the formation of the outer spore coat. We propose a unifying mechanism for nucleation and self-assembly of this crystalline layer on the outer spore coat surface.

  8. Presence survival spores of Bacillus thuringiensis varieties in grain warehouse

    Directory of Open Access Journals (Sweden)

    Sánchez-Yáñez Juan Manuel

    2016-08-01

    Full Text Available Genus Bacillus thuringiensis (Bt synthesized spores and crystals toxic to pest-insects in agriculture. Bt is comospolitan then possible to isolate some subspecies or varieties from warehouse. The aims of study were: i to isolate Bt varieties from grain at werehouse ii to evaluate Bt toxicity on Spodoptera frugiperda and Shit-ophilus zeamaisese iii to analyze Bt spores persistence in Zea mays grains at werehouse compared to same Bt on grains exposed to sun radiation. Results showed that at werehouse were recovered more than one variety of Bt spores. According to each isolate Bt1 o Bt2 were toxic to S. frugiperda or S. zeamaisese. One those Bt belong to var morrisoni. At werehouse these spores on Z. mays grains surviving more time, while the same spores exposed to boicide sun radiation they died.

  9. The molecular timeline of a reviving bacterial spore.

    Science.gov (United States)

    Sinai, Lior; Rosenberg, Alex; Smith, Yoav; Segev, Einat; Ben-Yehuda, Sigal

    2015-02-19

    The bacterial spore can rapidly convert from a dormant to a fully active cell. Here we study this remarkable cellular transition in Bacillus subtilis and reveal the identity of the newly synthesized proteins throughout spore revival. Our analysis uncovers a highly ordered developmental program that correlates with the spore morphological changes and reveals the spatial and temporal molecular events fundamental to reconstruct a cell. As opposed to current knowledge, we found that translation takes place during the earliest revival event, termed germination, a process hitherto considered to occur without the need for any macromolecule synthesis. Furthermore, we demonstrate that translation is required for execution of germination and relies on the bona fide translational factors RpmE and Tig. Our study sheds light on the spore revival process and on the vital building blocks underlying cellular awakening, thereby paving the way for designing new antimicrobial agents to eradicate spore-forming pathogens.

  10. Rapid Detection of Viable Bacillus anthracis Spores in Environmental Samples by Using Engineered Reporter Phages.

    Science.gov (United States)

    Sharp, Natasha J; Molineux, Ian J; Page, Martin A; Schofield, David A

    2016-04-01

    Bacillus anthracis, the causative agent of anthrax, was utilized as a bioterrorism agent in 2001 when spores were distributed via the U.S. postal system. In responding to this event, the Federal Bureau of Investigation used traditional bacterial culture viability assays to ascertain the extent of contamination of the postal facilities within 24 to 48 h of environmental sample acquisition. Here, we describe a low-complexity, second-generation reporter phage assay for the rapid detection of viableB. anthracis spores in environmental samples. The assay uses an engineered B. anthracis reporter phage (Wβ::luxAB-2) which transduces bioluminescence to infected cells. To facilitate low-level environmental detection and maximize the signal response, expression of luxABin an earlier version of the reporter phage (Wβ::luxAB-1) was optimized. These alterations prolonged signal kinetics, increased light output, and improved assay sensitivity. Using Wβ::luxAB-2, detection of B. anthracis spores was 1 CFU in 8 h from pure cultures and as low as 10 CFU/g in sterile soil but increased to 10(5)CFU/g in unprocessed soil due to an unstable signal and the presence of competing bacteria. Inclusion of semiselective medium, mediated by a phage-expressed antibiotic resistance gene, maintained signal stability and enabled the detection of 10(4)CFU/g in 6 h. The assay does not require spore extraction and relies on the phage infecting germinating cells directly in the soil sample. This reporter phage displays promise for the rapid detection of low levels of spores on clean surfaces and also in grossly contaminated environmental samples from complex matrices such as soils.

  11. Rapid Detection of Viable Bacillus anthracis Spores in Environmental Samples by Using Engineered Reporter Phages

    Science.gov (United States)

    Sharp, Natasha J.; Molineux, Ian J.; Page, Martin A.

    2016-01-01

    Bacillus anthracis, the causative agent of anthrax, was utilized as a bioterrorism agent in 2001 when spores were distributed via the U.S. postal system. In responding to this event, the Federal Bureau of Investigation used traditional bacterial culture viability assays to ascertain the extent of contamination of the postal facilities within 24 to 48 h of environmental sample acquisition. Here, we describe a low-complexity, second-generation reporter phage assay for the rapid detection of viable B. anthracis spores in environmental samples. The assay uses an engineered B. anthracis reporter phage (Wβ::luxAB-2) which transduces bioluminescence to infected cells. To facilitate low-level environmental detection and maximize the signal response, expression of luxAB in an earlier version of the reporter phage (Wβ::luxAB-1) was optimized. These alterations prolonged signal kinetics, increased light output, and improved assay sensitivity. Using Wβ::luxAB-2, detection of B. anthracis spores was 1 CFU in 8 h from pure cultures and as low as 10 CFU/g in sterile soil but increased to 105 CFU/g in unprocessed soil due to an unstable signal and the presence of competing bacteria. Inclusion of semiselective medium, mediated by a phage-expressed antibiotic resistance gene, maintained signal stability and enabled the detection of 104 CFU/g in 6 h. The assay does not require spore extraction and relies on the phage infecting germinating cells directly in the soil sample. This reporter phage displays promise for the rapid detection of low levels of spores on clean surfaces and also in grossly contaminated environmental samples from complex matrices such as soils. PMID:26873316

  12. Decontamination Options for Drinking Water Contaminated with Bacillus anthracis Spores

    Energy Technology Data Exchange (ETDEWEB)

    Raber, E; Burklund, A

    2010-02-16

    Five parameters were evaluated with surrogates of Bacillus anthracis spores to determine effective decontamination options for use in a contaminated drinking water supply. The parameters were: (1) type of Bacillus spore surrogate (B. thuringiensis or B. atrophaeus); (2) spore concentration in suspension (10{sup 2} to 10{sup 6} spores/ml); (3) chemical characteristics of decontaminant [sodium dicholor-s-triazinetrione dihydrate (Dichlor), hydrogen peroxide, potassium peroxymonosulfate (Oxone), sodium hypochlorite, and VirkonS{reg_sign}]; (4) decontaminant concentration (0.01% to 5%); and (5) decontaminant exposure time (10 min to 24 hr). Results from 162 suspension tests with appropriate controls are reported. Hydrogen peroxide at a concentration of 5%, and Dichlor and sodium hypochlorite at a concentration of 2%, were effective at spore inactivation regardless of spore type tested, spore exposure time, or spore concentration evaluated. This is the first reported study of Dichlor as an effective decontaminant for B. anthracis spore surrogates. Dichlor's desirable characteristics of high oxidation potential, high level of free chlorine, and more neutral pH than that of other oxidizers evaluated appear to make it an excellent alternative. All three oxidizers were effective against B. atrophaeus spores in meeting EPA's biocide standard of greater than a 6 log kill after a 10-minute exposure time and at lower concentrations than typically reported for biocide use. Solutions of 5% VirkonS{reg_sign} and Oxone were less effective decontaminants than other options evaluated in this study and did not meet the EPA's efficacy standard for biocides. Differences in methods and procedures reported by other investigators make quantitative comparisons among studies difficult.

  13. Determination of fungal spore release from wet building materials.

    Science.gov (United States)

    Kildesø, J; Würtz, H; Nielsen, K F; Kruse, P; Wilkins, K; Thrane, U; Gravesen, S; Nielsen, P A; Schneider, T

    2003-06-01

    The release and transport of fungal spores from water-damaged building materials is a key factor for understanding the exposure to particles of fungal origin as a possible cause of adverse health effects associated to growth of fungi indoors. In this study, the release of spores from nine species of typical indoor fungi has been measured under controlled conditions. The fungi were cultivated for a period of 4-6 weeks on sterilized wet wallpapered gypsum boards at a relative humidity (RH) of approximately 97%. A specially designed small chamber (P-FLEC) was placed on the gypsum board. The release of fungal spores was induced by well-defined jets of air impacting from rotating nozzles. The spores and other particles released from the surface were transported by the air flowing from the chamber through a top outlet to a particle counter and sizer. For two of the fungi (Penicillium chrysogenum and Trichoderma harzianum), the number of spores produced on the gypsum board and subsequently released was quantified. Also the relationship between air velocities from 0.3 to 3 m/s over the surface and spore release has been measured. The method was found to give very reproducible results for each fungal isolate, whereas the spore release is very different for different fungi under identical conditions. Also, the relationship between air velocity and spore release depends on the fungus. For some fungi a significant number of particles smaller than the spore size were released. The method applied in the study may also be useful for field studies and for generation of spores for exposure studies.

  14. Fungi in a changing world: growth rates will be elevated, but spore production may decrease in future climates

    Science.gov (United States)

    Damialis, Athanasios; Mohammad, Aqilah B.; Halley, John M.; Gange, Alan C.

    2015-09-01

    Very little is known about the impact of climate change on fungi and especially on spore production. Fungal spores can be allergenic, thus being important for human health. The aim of this study was to investigate how climate change influences the responsive ability of fungi by simulating differing environmental regimes. Fungal species with high spore allergenic potential and atmospheric abundance were grown and experimentally examined under a variety of temperatures and different nutrient availability. Each represented the average decadal air temperature of the 1980s, 1990s and 2000s in the UK, along with an Intergovernmental Panel on Climate Change (IPCC) climate change scenario for 2100. All tests were run on six fungal species: Alternaria alternata, Aspergillus niger, Botrytis cinerea, Cladosporium cladosporioides, Cladosporium oxysporum and Epicoccum purpurascens. Mycelium growth rate and spore production were examined on each single species and competitive capacity among species combinations in pairs. All fungal species grew faster at higher temperatures, and this was more pronounced for the temperature projection in 2100. Most species grew faster when there was lower nutrient availability. Exceptions were the species with the highest growth rate ( E. purpurascens) and with the highest competition capacity ( A. alternata). Most species (except for E. purpurascens) produced more spores in the richer nutrient medium but fewer as temperature increased. C. cladosporioides was an exception, exponentially increasing its spore production in the temperature of the 2100 scenario. Regarding competitive capacity, no species displayed any significant alterations within the environmental range checked. It is suggested that in future climates, fungi will display dramatic growth responses, with faster mycelium growth and lower spore production, with questions risen on relevant allergen potential.

  15. Survival of Spores of Trichoderma longibrachiatum in Space: data from the Space Experiment SPORES on EXPOSE-R

    Science.gov (United States)

    Neuberger, Katja; Lux-Endrich, Astrid; Panitz, Corinna

    2015-01-01

    In the space experiment `Spores in artificial meteorites' (SPORES), spores of the fungus Trichoderma longibrachiatum were exposed to low-Earth orbit for nearly 2 years on board the EXPOSE-R facility outside of the International Space Station. The environmental conditions tested in space were: space vacuum at 10-7-10-4 Pa or argon atmosphere at 105 Pa as inert gas atmosphere, solar extraterrestrial ultraviolet (UV) radiation at λ > 110 nm or λ > 200 nm with fluences up to 5.8 × 108 J m-2, cosmic radiation of a total dose range from 225 to 320 mGy, and temperature fluctuations from -25 to +50°C, applied isolated or in combination. Comparable control experiments were performed on ground. After retrieval, viability of spores was analysed by two methods: (i) ethidium bromide staining and (ii) test of germination capability. About 30% of the spores in vacuum survived the space travel, if shielded against insolation. However, in most cases no significant decrease was observed for spores exposed in addition to the full spectrum of solar UV irradiation. As the spores were exposed in clusters, the outer layers of spores may have shielded the inner part. The results give some information about the likelihood of lithopanspermia, the natural transfer of micro-organisms between planets. In addition to the parameters of outer space, sojourn time in space seems to be one of the limiting parameters.

  16. Methods for neutralizing anthrax or anthrax spores

    Science.gov (United States)

    Sloan, Mark A; Vivekandanda, Jeevalatha; Holwitt, Eric A; Kiel, Johnathan L

    2013-02-26

    The present invention concerns methods, compositions and apparatus for neutralizing bioagents, wherein bioagents comprise biowarfare agents, biohazardous agents, biological agents and/or infectious agents. The methods comprise exposing the bioagent to an organic semiconductor and exposing the bioagent and organic semiconductor to a source of energy. Although any source of energy is contemplated, in some embodiments the energy comprises visible light, ultraviolet, infrared, radiofrequency, microwave, laser radiation, pulsed corona discharge or electron beam radiation. Exemplary organic semiconductors include DAT and DALM. In certain embodiments, the organic semiconductor may be attached to one or more binding moieties, such as an antibody, antibody fragment, or nucleic acid ligand. Preferably, the binding moiety has a binding affinity for one or more bioagents to be neutralized. Other embodiments concern an apparatus comprising an organic semiconductor and an energy source. In preferred embodiments, the methods, compositions and apparatus are used for neutralizing anthrax spores.

  17. Germination Requirements of Bacillus macerans Spores

    Science.gov (United States)

    Sacks, L. E.; Thompson, P. A.

    1971-01-01

    2-Phenylacetamide is an effective germinant for spores of five strains of Bacillus macerans, particularly in the presence of fructose. Benzyl penicillin, the phenyl acetamide derivative of penicillin, and phenylacetic acid are also good germinants. l-Asparagine is an excellent germinant for four strains. α-Amino-butyric acid is moderately effective. Pyridoxine, pyridoxal, adenine, and 2,6-diaminopurine are potent germinants for NCA strain 7X1 only. d-Glucose is a powerful germinant for strain B-70 only. d-Fructose and d-ribose strongly potentiate germination induced by other germinants (except l-asparagine) but have only weak activity by themselves. Niacinamide and nicotinamide-adenine dinucleotide, inactive by themselves, are active in the presence of fructose or ribose. Effects of pH, ion concentration, and temperature are described. PMID:4251279

  18. Viability of Clostridium sporogenes spores after CaO hygienization of meat waste.

    Science.gov (United States)

    Bauza-Kaszewska, Justyna; Paluszak, Zbigniew; Skowron, Krzysztof

    2014-01-01

    The occurrence of the pathogenic species C. perfringens and C. botulinum spores in animal by-products poses a potential epidemiological hazard. Strong entero- and neurotoxins produced by these bacteria adversely affect human health. To inactivate pathogens present in animal by-products, waste must be subjected to various methods of sanitization. The aim of the presented study was to estimate the effect of different doses of CaO on the viability of spores Clostridium sporogenes in meat wastes category 3. During the research, two doses of burnt lime were added to the poultry mince meat and meat mixed with swine blood contaminated with Clostridium sporogenes spore suspension. Half of the samples collected for microbiological analyses were buffered to achieve the pH level ~7, the other were examined without pH neutralization. To estimate the spore number, 10-fold dilution series in peptone water was prepared and heat-treated at 80 °C for 10 min. After cooling-down, one milliliter of each dilution was pour-plated onto DRCM medium solidified with agar. Statistical analysis were performed using the Statistica software. Application of 70% CaO caused complete inactivation of Clostridium spores in meat wastes after 48 hours. The highest temperature achieved during the experiment was 67 °C. Rapid alkalization of the biomass resulted in increasing pH to values exceeding 12. The effect of liming was not dependent on the meat wastes composition nor CaO dose. The experiment proved the efficiency of liming as a method of animal by-products sanitization. Application of the obtained results may help reduce the epidemiological risk and ensure safety to people handling meat wastes at each stage of their processing and utilization.

  19. Viability of Clostridium sporogenes spores after CaO hygienization of meat waste

    Directory of Open Access Journals (Sweden)

    Justyna Bauza-Kaszewska

    2014-09-01

    Full Text Available The occurrence of the pathogenic species [i]C. perfringens[/i] and [i]C. botulinum spores[/i] in animal by-products poses a potential epidemiological hazard. Strong entero- and neurotoxins produced by these bacteria adversely affect human health. To inactivate pathogens present in animal by-products, waste must be subjected to various methods of sanitization. The aim of the presented study was to estimate the effect of different doses of CaO on the viability of spores [i] Clostridium sporogenes[/i] in meat wastes category 3. During the research, two doses of burnt lime were added to the poultry mince meat and meat mixed with swine blood contaminated with [i]Clostridium sporogenes[/i] spore suspension. Half of the samples collected for microbiological analyses were buffered to achieve the pH level ~7, the other were examined without pH neutralization. To estimate the spore number, 10-fold dilution series in peptone water was prepared and heat-treated at 80 °C for 10 min. After cooling-down, one milliliter of each dilution was pour-plated onto DRCM medium solidified with agar. Statistical analysis were performed using the Statistica software. Application of 70% CaO caused complete inactivation of [i]Clostridium spores[/i] in meat wastes after 48 hours. The highest temperature achieved during the experiment was 67 °C. Rapid alkalization of the biomass resulted in increasing pH to values exceeding 12. The effect of liming was not dependent on the meat wastes composition nor CaO dose. The experiment proved the efficiency of liming as a method of animal by-products sanitization. Application of the obtained results may help reduce the epidemiological risk and ensure safety to people handling meat wastes at each stage of their processing and utilization.

  20. Online monitoring of Escherichia coli and Bacillus thuringiensis spore inactivation after advanced oxidation treatment.

    Science.gov (United States)

    Sherchan, Samendra P; Snyder, Shane A; Gerba, Charles P; Pepper, Ian L

    2014-01-01

    Various studies have shown that advanced oxidation processes (AOPs) such as UV light in combination with hydrogen peroxide is an efficient process for the removal of a large variety of emerging contaminants including microorganisms. The mechanism of destruction in the presence of hydrogen peroxide (H2O2) is the enhanced formation of hydroxyl (·OH) radicals, which have a high oxidation potential. The goal of this study was to utilize in-line advanced oxidation to inactivate microbes, and document the inactivation via an in-line, real-time sensor. Escherichia coli cells and Bacillus thuringiensis spores were exposed to UV/H2O2 treatment in DI water, and the online sensor BioSentry(®) was evaluated for its potential to monitor inactivation in real-time. B. thuringiensis was selected as a non-pathogenic surrogate for B. anthracis, the causative agent of anthrax and a proven biological weapon. UV radiation and UV/H2O2 exposure resulted in a >6 log10 reduction of the viable culturable counts of E. coli vegetative cells, and a 3 log10 reduction of B. thuringiensis spores. Scanning electron microscopy of the treated samples revealed severe damage on the surface of most E. coli cells, yet there was no significant change observed in the morphology of the B. thuringiensis spores. Following AOP exposure, the BioSentry sensor showed an increase in the categories of unknown, rod and spores counts, but overall, did not correspond well with viable count assays. Data from this study show that advanced oxidation processes effectively inactivate E. coli vegetative cells, but not B. thuringiensis spores, which were more resistant to AOP. Further, the BioSentry in-line sensor was not successful in documenting destruction of the microbial cells in real-time.

  1. Thermal and Pressure-Assisted Thermal Destruction Kinetics for Spores of Type A Clostridium botulinum and Clostridium sporogenes PA3679.

    Science.gov (United States)

    Reddy, N Rukma; Patazca, Eduardo; Morrissey, Travis R; Skinner, Guy E; Loeza, Viviana; Schill, Kristin M; Larkin, John W

    2016-02-01

    The purpose of this study was to determine the inactivation kinetics of the spores of the most resistant proteolytic Clostridium botulinum strains (Giorgio-A and 69-A, as determined from an earlier screening study) and of Clostridium sporogenes PA3679 and to compare the thermal and pressure-assisted thermal resistance of these spores. Spores of these strains were prepared using a biphasic medium method. C. sporogenes PA3679 spores were heat treated before spore preparation. Using laboratory-scale and pilot-scale pressure test systems, spores of Giorgio-A, 69-A, and PA3679 suspended in ACES [N-(2-acetamido)-2-aminoethanesulfonic acid] buffer (pH 7.0) were exposed to various combinations of temperature (93 to 121°C) and pressure (0.1 to 750 MPa) to determine their resistance. More than a 5-log reduction occurred after 3 min at 113°C for spores of Giorgio-A and 69-A and after 5 min at 117°C for spores of PA3679. A combination of high temperatures (93 to 121°C) and pressures yielded greater log reductions of spores of Giorgio-A, 69-A, and PA3679 compared with reduction obtained with high temperatures alone. No survivors from initial levels (>5.0 log CFU) of Giorgio-A and 69-A were detected when processed at a combination of high temperature (117 and 121°C) and high pressure (600 and 750 MPa) for 4.5-log reduction of PA3679 spores. Thermal D-values of Giorgio-A, 69-A, and PA3679 spores decreased (i.e., 29.1 to 0.33 min for Giorgio-A, 40.5 to 0.27 min for 69-A, and 335.2 to 2.16 min for PA3679) as the temperature increased from 97 to 117°C. Pressure-assisted thermal D-values of Giorgio-A, 69-A, and PA3679 also decreased as temperature increased from 97 to 121°C at both pressures (600 and 750 MPa) (i.e., 17.19 to 0.15 min for Giorgio-A, 9.58 to 0.15 min for 69-A, and 12.93 to 0.33 min for PA3679 at 600 MPa). At higher temperatures (117 or 121°C), increasing pressure from 600 to 750 MPa had an effect on pressure-assisted thermal D-values of PA3679 (i.e., at 117

  2. Activity of spores and extracellular proteins from six Cry+ strains and a Cry- strain of Bacillus thuringiensis subsp. kurstaki against the western spruce budworm, Choristoneura occidentalis (Lepidoptera: Tortricidae).

    Science.gov (United States)

    Kalmykova, Galina; Burtseva, Ljudmila; Milne, Ross; van Frankenhuyzen, Kees

    2009-05-01

    We characterized insecticidal activity of previously untested strains of Bacillus thuringiensis kurstaki belonging to two crystal serovars (K-1 and K-73) against the western spruce budworm (Choristoneura occidentalis Freeman 1967). By testing various components, we demonstrated that spores play a critical role in the pathogenesis of each strain. Spore-free crystals caused low mortality and purified spores were generally not toxic. The addition of spores to purified protoxin increased toxicity several hundred-fold, regardless of the parental strain from which the spores or protoxins were derived. The crystal and spore components did not account for full insecticidal activity of whole sporulated cultures owing to the toxicity of soluble proteins that are secreted during cell growth. We observed a marked difference in toxicity of secreted proteins between the K-1 and K-73 type strains, with the K-1 preparations causing much higher mortality, mass reduction, and inhibition of pupation. There was a consistent correlation between relative toxicity of secreted protein preparations and the presence and quantity of the Vip3A protein, suggesting that this protein contributes to the virulence of B. thuringiensis subsp. kurstaki in western spruce budworm larvae. However, other virulence factors have to be invoked to explain the synergizing effect of spores from both K-1 and K-73 strains on Cry protein toxicity.

  3. Infection of Tribolium castaneum with Bacillus thuringiensis: quantification of bacterial replication within cadavers, transmission via cannibalism, and inhibition of spore germination.

    Science.gov (United States)

    Milutinović, Barbara; Höfling, Christina; Futo, Momir; Scharsack, Jörn P; Kurtz, Joachim

    2015-12-01

    Reproduction within a host and transmission to the next host are crucial for the virulence and fitness of pathogens. Nevertheless, basic knowledge about such parameters is often missing from the literature, even for well-studied bacteria, such as Bacillus thuringiensis, an endospore-forming insect pathogen, which infects its hosts via the oral route. To characterize bacterial replication success, we made use of an experimental oral infection system for the red flour beetle Tribolium castaneum and developed a flow cytometric assay for the quantification of both spore ingestion by the individual beetle larvae and the resulting spore load after bacterial replication and resporulation within cadavers. On average, spore numbers increased 460-fold, showing that Bacillus thuringiensis grows and replicates successfully in insect cadavers. By inoculating cadaver-derived spores and spores from bacterial stock cultures into nutrient medium, we next investigated outgrowth characteristics of vegetative cells and found that cadaver-derived bacteria showed reduced growth compared to bacteria from the stock cultures. Interestingly, this reduced growth was a consequence of inhibited spore germination, probably originating from the host and resulting in reduced host mortality in subsequent infections by cadaver-derived spores. Nevertheless, we further showed that Bacillus thuringiensis transmission was possible via larval cannibalism when no other food was offered. These results contribute to our understanding of the ecology of Bacillus thuringiensis as an insect pathogen. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  4. Infection of Tribolium castaneum with Bacillus thuringiensis: Quantification of Bacterial Replication within Cadavers, Transmission via Cannibalism, and Inhibition of Spore Germination

    Science.gov (United States)

    Milutinović, Barbara; Höfling, Christina; Futo, Momir; Scharsack, Jörn P.

    2015-01-01

    Reproduction within a host and transmission to the next host are crucial for the virulence and fitness of pathogens. Nevertheless, basic knowledge about such parameters is often missing from the literature, even for well-studied bacteria, such as Bacillus thuringiensis, an endospore-forming insect pathogen, which infects its hosts via the oral route. To characterize bacterial replication success, we made use of an experimental oral infection system for the red flour beetle Tribolium castaneum and developed a flow cytometric assay for the quantification of both spore ingestion by the individual beetle larvae and the resulting spore load after bacterial replication and resporulation within cadavers. On average, spore numbers increased 460-fold, showing that Bacillus thuringiensis grows and replicates successfully in insect cadavers. By inoculating cadaver-derived spores and spores from bacterial stock cultures into nutrient medium, we next investigated outgrowth characteristics of vegetative cells and found that cadaver-derived bacteria showed reduced growth compared to bacteria from the stock cultures. Interestingly, this reduced growth was a consequence of inhibited spore germination, probably originating from the host and resulting in reduced host mortality in subsequent infections by cadaver-derived spores. Nevertheless, we further showed that Bacillus thuringiensis transmission was possible via larval cannibalism when no other food was offered. These results contribute to our understanding of the ecology of Bacillus thuringiensis as an insect pathogen. PMID:26386058

  5. Sterilization Resistance of Bacterial Spores Explained with Water Chemistry.

    Science.gov (United States)

    Friedline, Anthony W; Zachariah, Malcolm M; Middaugh, Amy N; Garimella, Ravindranath; Vaishampayan, Parag A; Rice, Charles V

    2015-11-01

    Bacterial spores can survive for long periods without nutrients and in harsh environmental conditions. This survival is influenced by the structure of the spore, the presence of protective compounds, and water retention. These compounds, and the physical state of water in particular, allow some species of bacterial spores to survive sterilization schemes with hydrogen peroxide and UV light. The chemical nature of the spore core and its water has been a subject of some contention and the chemical environment of the water impacts resistance paradigms. Either the spore has a glassy core, where water is immobilized along with other core components, or the core is gel-like with mobile water diffusion. These properties affect the movement of peroxide and radical species, and hence resistance. Deuterium solid-state NMR experiments are useful for examining the nature of the water inside the spore. Previous work in our lab with spores of Bacillus subtilis indicate that, for spores, the core water is in a more immobilized state than expected for the gel-like core theory, suggesting a glassy core environment. Here, we report deuterium solid-state NMR observations of the water within UV- and peroxide-resistant spores from Bacillus pumilus SAFR-032. Variable-temperature NMR experiments indicate no change in the line shape after heating to 50 °C, but an overall decrease in signal after heating to 100 °C. These results show glass-like core dynamics within B. pumilus SAFR-032 that may be the potential source of its known UV-resistance properties. The observed NMR traits can be attributed to the presence of an exosporium containing additional labile deuterons that can aid in the deactivation of sterilizing agents.

  6. Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

    Science.gov (United States)

    Egan, Kevin; Field, Des; Rea, Mary C; Ross, R Paul; Hill, Colin; Cotter, Paul D

    2016-01-01

    Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB). Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable spores to be more

  7. Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

    Directory of Open Access Journals (Sweden)

    Kevin eEgan

    2016-04-01

    Full Text Available Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB. Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural, approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable

  8. Spore formation and toxin production in Clostridium difficile biofilms.

    Directory of Open Access Journals (Sweden)

    Ekaterina G Semenyuk

    Full Text Available The ability to grow as a biofilm can facilitate survival of bacteria in the environment and promote infection. To better characterize biofilm formation in the pathogen Clostridium difficile, we established a colony biofilm culture method for this organism on a polycarbonate filter, and analyzed the matrix and the cells in biofilms from a variety of clinical isolates over several days of biofilm culture. We found that biofilms readily formed in all strains analyzed, and that spores were abundant within about 6 days. We also found that extracellular DNA (eDNA, polysaccharide and protein was readily detected in the matrix of all strains, including the major toxins A and/or B, in toxigenic strains. All the strains we analyzed formed spores. Apart from strains 630 and VPI10463, which sporulated in the biofilm at relatively low frequencies, the frequencies of biofilm sporulation varied between 46 and 65%, suggesting that variations in sporulation levels among strains is unlikely to be a major factor in variation in the severity of disease. Spores in biofilms also had reduced germination efficiency compared to spores obtained by a conventional sporulation protocol. Transmission electron microscopy revealed that in 3 day-old biofilms, the outermost structure of the spore is a lightly staining coat. However, after 6 days, material that resembles cell debris in the matrix surrounds the spore, and darkly staining granules are closely associated with the spores surface. In 14 day-old biofilms, relatively few spores are surrounded by the apparent cell debris, and the surface-associated granules are present at higher density at the coat surface. Finally, we showed that biofilm cells possess 100-fold greater resistance to the antibiotic metronidazole then do cells cultured in liquid media. Taken together, our data suggest that C. difficile cells and spores in biofilms have specialized properties that may facilitate infection.

  9. Spore formation and toxin production in Clostridium difficile biofilms.

    Science.gov (United States)

    Semenyuk, Ekaterina G; Laning, Michelle L; Foley, Jennifer; Johnston, Pehga F; Knight, Katherine L; Gerding, Dale N; Driks, Adam

    2014-01-01

    The ability to grow as a biofilm can facilitate survival of bacteria in the environment and promote infection. To better characterize biofilm formation in the pathogen Clostridium difficile, we established a colony biofilm culture method for this organism on a polycarbonate filter, and analyzed the matrix and the cells in biofilms from a variety of clinical isolates over several days of biofilm culture. We found that biofilms readily formed in all strains analyzed, and that spores were abundant within about 6 days. We also found that extracellular DNA (eDNA), polysaccharide and protein was readily detected in the matrix of all strains, including the major toxins A and/or B, in toxigenic strains. All the strains we analyzed formed spores. Apart from strains 630 and VPI10463, which sporulated in the biofilm at relatively low frequencies, the frequencies of biofilm sporulation varied between 46 and 65%, suggesting that variations in sporulation levels among strains is unlikely to be a major factor in variation in the severity of disease. Spores in biofilms also had reduced germination efficiency compared to spores obtained by a conventional sporulation protocol. Transmission electron microscopy revealed that in 3 day-old biofilms, the outermost structure of the spore is a lightly staining coat. However, after 6 days, material that resembles cell debris in the matrix surrounds the spore, and darkly staining granules are closely associated with the spores surface. In 14 day-old biofilms, relatively few spores are surrounded by the apparent cell debris, and the surface-associated granules are present at higher density at the coat surface. Finally, we showed that biofilm cells possess 100-fold greater resistance to the antibiotic metronidazole then do cells cultured in liquid media. Taken together, our data suggest that C. difficile cells and spores in biofilms have specialized properties that may facilitate infection.

  10. Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

    Science.gov (United States)

    Egan, Kevin; Field, Des; Rea, Mary C.; Ross, R. Paul; Hill, Colin; Cotter, Paul D.

    2016-01-01

    Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB). Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable spores to be more

  11. New pressure and temperature effects on bacterial spores

    Energy Technology Data Exchange (ETDEWEB)

    Mathys, A; Knorr, D [Berlin University of Technology, Department of Food Biotechnology and Food Process Engineering, Koenigin-Luise-Str. 22, D-14195 Berlin (Germany); Heinz, V [German Institute of Food Technology, p. o. box 1165, D-49601, Quackenbrueck (Germany)], E-mail: alexander.mathys@tu-berlin.de

    2008-07-15

    The mechanism of inactivation of bacterial spores by heat and pressure is still a matter of discussion. Obviously, the change of the dissociation equilibrium under pressure and temperature plays a dominant role in inactivation of microorganisms. Heat and pressure inactivation of Geobacillus. stearothermophilus spores at different initial pH-values in ACES and phosphate buffer confirmed this view. Thermal inactivation in ACES buffer at 122 deg. C resulted in higher logarithmic reductions. Contrary, after pressure treatment at 900 MPa with 80 deg. C phosphate buffer showed higher inactivation. These results indicated the different dissociation equilibrium shifts in buffer systems by heat and pressure. Due to preparation, storage and handling of highly concentrated spore suspensions the clumping and the formation of aggregates can hardly be avoided. Consequently, the impact of the agglomeration size distribution on the quantitative assessment of G. stearothermophilus spore inactivation was determined by using a three-fold dynamic optical backreflexion measurement. Two limiting cases have been discriminated in mathematical modelling: three dimensional, spherical packing for maximum spore count and two dimensional, circular packing for minimum spore count of a particular agglomerate. Thermal inactivation studies have been carried out in thin glass capillaries, where by using numerical simulations the non isothermal conditions were modelled and taken into account. It is shown that the shoulder formation often found in thermal spore inactivation can sufficiently be described by first-order inactivation kinetics when the agglomeration size is considered. In case of high pressure inactivation agglomerations could be strongly changed by high forces at compression and especially decompression phase. The physiological response of Bacillus licheniformis spores to high pressure was investigated using multiparameter flow cytometry. Spores were treated by high pressure at 150 MPa

  12. New pressure and temperature effects on bacterial spores

    Science.gov (United States)

    Mathys, A.; Heinz, V.; Knorr, D.

    2008-07-01

    The mechanism of inactivation of bacterial spores by heat and pressure is still a matter of discussion. Obviously, the change of the dissociation equilibrium under pressure and temperature plays a dominant role in inactivation of microorganisms. Heat and pressure inactivation of Geobacillus. stearothermophilus spores at different initial pH-values in ACES and phosphate buffer confirmed this view. Thermal inactivation in ACES buffer at 122°C resulted in higher logarithmic reductions. Contrary, after pressure treatment at 900 MPa with 80°C phosphate buffer showed higher inactivation. These results indicated the different dissociation equilibrium shifts in buffer systems by heat and pressure. Due to preparation, storage and handling of highly concentrated spore suspensions the clumping and the formation of aggregates can hardly be avoided. Consequently, the impact of the agglomeration size distribution on the quantitative assessment of G. stearothermophilus spore inactivation was determined by using a three-fold dynamic optical backreflexion measurement. Two limiting cases have been discriminated in mathematical modelling: three dimensional, spherical packing for maximum spore count and two dimensional, circular packing for minimum spore count of a particular agglomerate. Thermal inactivation studies have been carried out in thin glass capillaries, where by using numerical simulations the non isothermal conditions were modelled and taken into account. It is shown that the shoulder formation often found in thermal spore inactivation can sufficiently be described by first-order inactivation kinetics when the agglomeration size is considered. In case of high pressure inactivation agglomerations could be strongly changed by high forces at compression and especially decompression phase. The physiological response of Bacillus licheniformis spores to high pressure was investigated using multiparameter flow cytometry. Spores were treated by high pressure at 150 MPa with 37

  13. Inhibition of Ageratina adenophora on Spore Germination and Gametophyte Development of Macrothelypteris torresiana

    Institute of Scientific and Technical Information of China (English)

    Kai-Mei Zhang; Lei Shi; Chuang-Dao Jiang; Zhen-Yu Li

    2008-01-01

    Allalopathy of Ageratina adenophora plays an important role in its invasion. However, we have little knowledge of its allelpathic effects on ferns. In Petri dish bioassays, the inhibitory potential of aqueous leachates from roots, stems and leaves of A. adenophora was studied on the spore germination and gametophyte development of Macrothelypteris torresiana. All leachates Inhibited the spore germination and growth of the first rhizoid of M. torresiana and inhibitory effects Increased with increasing leachate concentrations. Root leachates proved most inhibitory. Gametophyte rhizoids of M. torresiana treated with stem and leaf leachates ofA. adenophora were erect, which was similar to those of the control. However, gametophyte rhizoids of M. torresiana treated with root leachates of A. adenophora were erect, but also curving or swollen. Moreover, curving and swollen rhizoids Increased with Increasing concentrations. As time went by, rhizoids treated with root leachates were not so curved and the swelling almost disappeared. Possible causes are discussed in the present study. The increasing concentrations of leaf leachates also delayed the stages of gametophyte development. With the treatment of root leachates, the delay was more obvious. Thus A. adenophora inhibited the spore germination and gametophyte development of M. torresiana and the root leachates were most inhibitory.

  14. Non-recombinant display of the B subunit of the heat labile toxin of Escherichia coli on wild type and mutant spores of Bacillus subtilis.

    Science.gov (United States)

    Isticato, Rachele; Sirec, Teja; Treppiccione, Lucia; Maurano, Francesco; De Felice, Maurilio; Rossi, Mauro; Ricca, Ezio

    2013-10-29

    Mucosal infections are a major global health problem and it is generally accepted that mucosal vaccination strategies, able to block infection at their entry site, would be preferable with respect to other prevention approaches. However, there are still relatively few mucosal vaccines available, mainly because of the lack of efficient delivery systems and of mucosal adjuvants. Recombinant bacterial spores displaying a heterologous antigen have been shown to induce protective immune responses and, therefore, proposed as a mucosal delivery system. A non-recombinant approach has been recently developed and tested to display antigens and enzymes. We report that the binding subunit of the heat-labile toxin (LTB) of Escherichia coli efficiently adsorbed on the surface of Bacillus subtilis spores. When nasally administered to groups of mice, spore-adsorbed LTB was able to induce a specific immune response with the production of serum IgG, fecal sIgA and of IFN-γ in spleen and mesenteric lymph nodes (MLN) of the immunized animals. Dot blotting experiments showed that the non-recombinant approach was more efficient than the recombinant system in displaying LTB and that the efficiency of display could be further increased by using mutant spores with an altered surface. In addition, immunofluorescence microscopy experiments showed that only when displayed on the spore surface by the non-recombinant approach LTB was found in its native, pentameric form. Our results indicate that non-recombinant spores displaying LTB pentamers can be administered by the nasal route to induce a Th1-biased, specific immune response. Mutant spores with an altered coat are more efficient than wild type spores in adsorbing the antigen, allowing the use of a reduced number of spores in immunization procedures. Efficiency of display, ability to display the native form of the antigen and to induce a specific immune response propose this non-recombinant delivery system as a powerful mucosal vaccine

  15. Arbuscular mycorrhizal fungi in chronically petroleum-contaminated soils in Mexico and the effects of petroleum hydrocarbons on spore germination.

    Science.gov (United States)

    Franco-Ramírez, Alicia; Ferrera-Cerrato, Ronald; Varela-Fregoso, Lucía; Pérez-Moreno, Jesús; Alarcón, Alejandro

    2007-10-01

    Arbuscular mycorrhizal fungi (AMF) have been hypothesized to enhance plant adaptation and growth in petroleum-contaminated soils. Nevertheless, neither AMF-biodiversity under chronically petroleum-contaminated soils nor spore germination response to petroleum hydrocarbons has been well studied. Chronically petroleum-contaminated rhizosphere soil and roots from Echinochloa polystachya, Citrus aurantifolia and C. aurantium were collected from Activo Cinco Presidentes, Tabasco, Mexico. Root colonization and spore abundance were evaluated. Additionally, rhizosphere soil samples were propagated using Sorghum vulgare L. as a plant trap under greenhouse conditions; subsequently, AMF-spores were identified. AMF-colonization ranged from 63 to 77% while spore number ranged from 715 to 912 in 100 g soil, suggesting that AMF tolerate the presence of petroleum hydrocarbons in the rhizosphere. From grass species, four AMF-morphospecies were identified: Glomus ambisporum, G. sinuosum (previously described as Sclerocystis sinuosum), Acaulospora laevis, and Ambispora gerdermanni. From citrus trees, four AMF-species were also identified: Scutellospora heterogama, G. ambisporum, Acaulospora scrobiculata, and G. citricola. In a second study, it was observed that spore germination and hyphal length of G. mosseae, G. ambisporum, and S. heterogama were significantly reduced by either volatile compounds of crude oil or increased concentrations of benzo[a ]pyrene or phenanthrene in water-agar.

  16. Effects of temperature and desiccation on ex situ conservation of nongreen fern spores

    Science.gov (United States)

    Conservation of the genetic diversity of ferns is limited by the paucity of ex situ spore banks. Conflicting reports of fern spore response to low temperature and moisture impedes establishment of fern spore banks. There is little information available to evaluate longevity of fern spores under dif...

  17. On the neutralization of bacterial spores in post-detonation flows

    Science.gov (United States)

    Gottiparthi, K. C.; Schulz, J. C.; Menon, S.

    2014-09-01

    In multiple operational scenarios, explosive charges are used to neutralize confined or unconfined stores of bacterial spores. The spore destruction is achieved by post-detonation combustion and mixing of hot detonation product gases with the ambient flow and spore clouds. In this work, blast wave interaction with bacterial spore clouds and the effect of post-detonation combustion on spore neutralization are investigated using numerical simulations. Spherical explosive charges (radius, = 5.9 cm) comprising of nitromethane are modeled in the vicinity of a spore cloud, and the spore kill in the post-detonation flow is quantified. The effect of the mass of the spores and the initial distance, , of the spore cloud from the explosive charge on the percentage of spores neutralized is investigated. When the spores are initially placed within a distance of 3.0, within 0.1 ms after detonation of the charge, all the spores are neutralized by the blast wave and the hot detonation product gases. In contrast, almost all the spores survived the explosion when is greater than 8.0. The percentage of intact spores varied from 0 to 100 for 3.0 8.0 with spore neutralization dependent on time spent by the spores in the post-detonation mixing/combustion zone.

  18. Does proximity to neighbours affect germination of spores of non-proteolytic Clostridium botulinum?

    Science.gov (United States)

    Webb, Martin D; Stringer, Sandra C; Le Marc, Yvan; Baranyi, József; Peck, Michael W

    2012-10-01

    It is recognised that inoculum size affects the rate and extent of bacterial spore germination. It has been proposed that this is due to spores interacting: molecules released from germinated spores trigger germination of dormant neighbours. This study investigated whether changes to the total number of spores in a system or proximity to other spores (local spore density) had a more significant effect on interaction between spores of non-proteolytic Clostridium botulinum strain Eklund 17B attached to defined areas of microscope slides. Both the number of spores attached to the slides and local spore density (number of spores per mm(2)) were varied by a factor of nine. Germination was observed microscopically at 15 °C for 8 h and the probability of, and time to, germination calculated from image analysis measurements. Statistical analysis revealed that the effect of total spore number on the probability of germination within 8 h was more significant than that of proximity to neighbours (local spore density); its influence on germination probability was approximately four-times greater. Total spore number had an even more significant affect on time to germination; it had a nine-fold greater influence than proximity to neighbours. The applied models provide a means to characterise, quantitatively, the effect of the total spore number on spore germination relative to the effect of proximity to neighbouring spores.

  19. Small Probes for Orbital Return of Experiments (SPORE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Analogous to the CubeSat standardization of micro-satellites, the SPORE flight system architecture will utilize a modular design approach to provide low-cost...

  20. Waterline ATS B. globigii spore water disinfection data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Disinfection of B. globigii spores (a non-pathogenic surrogate for B. anthracis) in clean and dirty water using the ATS-Waterline system, which uses ultraviolet...

  1. Alicyclobacillus acidoterrestris: new methods for inhibiting spore germination.

    Science.gov (United States)

    Bevilacqua, A; Sinigaglia, M; Corbo, M R

    2008-07-15

    For a long period the thermal processing has been considered as the only way to reduce the initial spore number of Alicyclobacillus acidoterrestris and prevent the spoilage of acidic beverage. New methods, however, were proposed by the literature to control spore germination both in laboratory media and in real systems. After a brief introduction on the impact of A. acidoterrestris in food microbiology and a description of enumeration methods and heat processing applied by the juices manufactures, a review of innovative approaches to inhibit and/or control spore germination is proposed. In particular, this paper focuses on two different topics; the 1st is the use of some natural compounds (monolaurin, lysozyme, nisin and essential oils) or some chemicals, conventional (like sodium-benzoate, organic acids, surfactants and chlorine dioxide) or not conventional (chlorine dioxide as gas). The 2nd topic is a description of some innovative methods to reduce the initial spore number (high hydrostatic and homogenisation pressures, radiation and microwaves).

  2. VUV absorption spectroscopy of bacterial spores and DNA components

    Science.gov (United States)

    Fiebrandt, Marcel; Lackmann, Jan-Wilm; Raguse, Marina; Moeller, Ralf; Awakowicz, Peter; Stapelmann, Katharina

    2017-01-01

    Low-pressure plasmas can be used to inactivate bacterial spores and sterilize goods for medical and pharmaceutical applications. A crucial factor are damages induced by UV and VUV radiation emitted by the plasma. To analyze inactivation processes and protection strategies of spores, absorption spectra of two B. subtilis strains are measured. The results indicate, that the inner and outer coat of the spore significantly contribute to the absorption of UV-C and also of the VUV, protecting the spore against radiation based damages. As the sample preparation can significantly influence the absorption spectra due to salt residues, the cleaning procedure and sample deposition is tested for its reproducibility by measuring DNA oligomers and pUC18 plasmid DNA. The measurements are compared and discussed with results from the literature, showing a strong decrease of the salt content enabling the detection of absorption structures in the samples.

  3. Oxidation mechanism of Penicillium digitatum spores through neutral oxygen radicals

    Science.gov (United States)

    Hashizume, Hiroshi; Ohta, Takayuki; Takeda, Keigo; Ishikawa, Kenji; Hori, Masaru; Ito, Masafumi

    2014-01-01

    To investigate the inactivation process of Penicillium digitatum spores through neutral oxygen species, the spores were treated with an atmospheric-pressure oxygen radical source and observed in-situ using a fluorescent confocal-laser microscope. The treated spores were stained with two fluorescent dyes, 1,1‧-dioctadecyl-3,3,Y,3‧-tetramethylindocarbocyanine perchlorate (DiI) and diphenyl-1-pyrenylphosphine (DPPP). The intracellular organelles as well as the cell membranes in the spores treated with the oxygen radical source were stained with DiI without a major morphological change of the membranes. DPPP staining revealed that the organelles were oxidized by the oxygen radical treatment. These results suggest that neutral oxygen species, especially atomic oxygen, induce a minor structural change or functional inhibition of cell membranes, which leads to the oxidation of the intracellular organelles through the penetration of reactive oxygen species into the cell.

  4. A versatile nano display platform from bacterial spore coat proteins.

    Science.gov (United States)

    Wu, I-Lin; Narayan, Kedar; Castaing, Jean-Philippe; Tian, Fang; Subramaniam, Sriram; Ramamurthi, Kumaran S

    2015-04-09

    Dormant bacterial spores are encased in a thick protein shell, the 'coat', which contains ∼70 different proteins. The coat protects the spore from environmental insults, and is among the most durable static structures in biology. Owing to extensive cross-linking among coat proteins, this structure has been recalcitrant to detailed biochemical analysis, so molecular details of how it assembles are largely unknown. Here, we reconstitute the basement layer of the coat atop spherical membranes supported by silica beads to create artificial spore-like particles. We report that these synthetic spore husk-encased lipid bilayers (SSHELs) assemble and polymerize into a static structure, mimicking in vivo basement layer assembly during sporulation in Bacillus subtilis. In addition, we demonstrate that SSHELs may be easily covalently modified with small molecules and proteins. We propose that SSHELs may be versatile display platforms for drugs and vaccines in clinical settings, or for enzymes that neutralize pollutants for environmental remediation.

  5. Spore-forming bacteria and their utilisation as probiotics.

    Science.gov (United States)

    Bader, J; Albin, A; Stahl, U

    2012-03-01

    In this review article, the beneficial application of bacterial spore formers as probiotics in the food industry is discussed based on the knowledge gleaned from current publications. The summary of new scientific results provides evidence of the advantages of the utilisation of Bacillus or Clostridium strains in the food industry. Both bacteria are able to produce a very stable duration form: the endospore. Compared to the widely used lactic acid bacteria, bacterial spores offer the advantage of a higher survival rate during the acidic stomach passage and better stability during the processing and storage of the food product. In many food products, germination of the spores does not occur. Hence the product quality of the food is not affected because of their inactive metabolism. Besides the possible utilisation and functional properties, an overview of the fast-developing knowledge about the mechanisms of the beneficial health effects of spore-forming bacteria is provided.

  6. Pharmacologic and toxicologic evaluation of C. novyi-NT spores.

    Science.gov (United States)

    Diaz, Luis A; Cheong, Ian; Foss, Catherine A; Zhang, Xiaosong; Peters, Brock A; Agrawal, Nishant; Bettegowda, Chetan; Karim, Baktiar; Liu, Guosheng; Khan, Khalid; Huang, Xin; Kohli, Manu; Dang, Long H; Hwang, Paul; Vogelstein, Ahava; Garrett-Mayer, Elizabeth; Kobrin, Barry; Pomper, Martin; Zhou, Shibin; Kinzler, Kenneth W; Vogelstein, Bert; Huso, David L

    2005-12-01

    Clostridium novyi-NT (C. novyi-NT) spores have been shown to be potent therapeutic agents in experimental tumors of mice and rabbits. In the present study, pharmacologic and toxicologic studies were performed to better understand the factors influencing the efficacy and toxicity of this form of therapy. We found that spores were rapidly cleared from the circulation by the reticuloendothelial system. Even after large doses were administered, no clinical toxicity was observed in healthy mice or rabbits. The spores were also not toxic in mice harboring poorly vascularized non-neoplastic lesions, including myocardial infarcts. In tumor-bearing mice, toxicity appeared related to tumor size and spore dose, as expected with any bacterial infection. However, there was no laboratory or histopathologic evidence of sepsis, and the toxicity could be effectively controlled by simple hydration.

  7. In vitro spore germination and gametophytic growth development of ...

    African Journals Online (AJOL)

    SAM

    2014-06-04

    Jun 4, 2014 ... Maximum spore germination rates (84%) were observed in. 70 g/L of sucrose and .... two weeks and gametophyte growth rates (length, width of ..... Smith AR, Pryer KM, Schuettpelz E, Korall P, Schneider H, Wolf PG. (2006).

  8. Late Silurian trilete spores from northern Jiangsu, China.

    Science.gov (United States)

    Wang; Li

    2000-08-01

    The Late Silurian is generally considered to a particular significant key period in the study of early land vascular plants. A trilete spore assemblage of the Upper Silurian is described from northern Jiangsu, China. This assemblage comprises 11 genera and 20 species of trilete spores (including laevigate, apiculate, perinotrilite, patinate, rarely distally murornate and equatorially crassitate, and three indeterminate trilete miospores forms). It has similarities to those described from coeval assemblages from around the world (e.g., England and South Wales; Tripolitania, Libya; Cornwallis Island, Canadian Arctic; Northwest Spain). The rare cryptospore, only one specimen (Tetrahedraletes sp.) had been found to be associated with the Chinese trilete spore assemblage. The discovery of the trilete spores from Late Silurian rocks indicates the existence of early land plants, some possibly vascular, at that time in northern Jiangsu, China.

  9. Formation of non-viable spores of Dictyostelium discoideum by UV-irradiation and caffeine

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, T.; Hazama, M.; Okaichi, K.; Nozu, K. (Nara Medical Univ., Kashihara (Japan))

    1982-09-01

    The spores formed from amoeboid cells of the wild type strain of Dictyostelium discoideum after UV-irradiation were characterized. Cell differentiation in the presence of caffeine after a fluence of 300 J/m/sup 2/ resulted in a population of spores which was 98% non-viable. The UV-irradiation did not affect the conversion of the spores to swollen spores but did affect the conversion of swollen spores to amoeboid cells. When the germination of the spores was done without caffeine, only a small effect on conversion of swollen spores to amoeboid cells and on the beginning of growth was detected. On the other hand, in the presence of caffeine, the spores had a remarkable delay in both. It was also shown that few, if any, pyrimidine dimers exist in the DNA of the non-viable spores. Possible mechanisms of formation of non-viable spores are discussed.

  10. Effects of Chlorine Dioxide on Spore Structural and Fuctional Properties

    Science.gov (United States)

    2006-05-31

    A., Price, B., Leighton, T. and K. Wheeler. 2003. Kinetics of size changes of individual Bacillus thuringiensis spores in response to changes in...vegetative growth . The germination process involves a defined temporal order of events, characterized initially by hydrolysis of the spore coat and...capable of early germination but not resumption of vegetative growth and cell division. We have explored the use of rapid spectrophotometric assays to

  11. Effect of Nanofibers on Spore Penetration and Lunar Dust Filtration

    OpenAIRE

    Phil Gibson, Ph.D.; Heidi Schreuder-Gibson, Ph.D.; Robert Stote; Margaret Roylance, Ph.D.; Cathy Capone; Masami Nakagawa, Ph.D.

    2008-01-01

    The results of two separate studies on biological spore penetration and simulated lunar dust filtration illustrate the use of nanofibers in some nonstandard filtration applications (nanofibers are generally defined as having diameters of less than a micron). In the first study, a variety of microporous liners containing microfibers and nanofibers were combined with cotton-based fabrics in order to filter aerosolized spores. The aerosol penetration resistance of the nanofiber-lined fabrics was...

  12. Fate of ingested Clostridium difficile spores in mice.

    Directory of Open Access Journals (Sweden)

    Amber Howerton

    Full Text Available Clostridium difficile infection (CDI is a leading cause of antibiotic-associated diarrhea, a major nosocomial complication. The infective form of C. difficile is the spore, a dormant and resistant structure that forms under stress. Although spore germination is the first committed step in CDI onset, the temporal and spatial distribution of ingested C. difficile spores is not clearly understood. We recently reported that CamSA, a synthetic bile salt analog, inhibits C. difficile spore germination in vitro and in vivo. In this study, we took advantage of the anti-germination activity of bile salts to determine the fate of ingested C. difficile spores. We tested four different bile salts for efficacy in preventing CDI. Since CamSA was the only anti-germinant tested able to prevent signs of CDI, we characterized CamSa's in vitro stability, distribution, and cytotoxicity. We report that CamSA is stable to simulated gastrointestinal (GI environments, but will be degraded by members of the natural microbiota found in a healthy gut. Our data suggest that CamSA will not be systemically available, but instead will be localized to the GI tract. Since in vitro pharmacological parameters were acceptable, CamSA was used to probe the mouse model of CDI. By varying the timing of CamSA dosage, we estimated that C. difficile spores germinated and established infection less than 10 hours after ingestion. We also showed that ingested C. difficile spores rapidly transited through the GI tract and accumulated in the colon and cecum of CamSA-treated mice. From there, C. difficile spores were slowly shed over a 96-hour period. To our knowledge, this is the first report of using molecular probes to obtain disease progression information for C. difficile infection.

  13. Structural Analysis of Bacillus subtilis Spore Peptidoglycan during Sporulation

    OpenAIRE

    2000-01-01

    A major structural element of bacterial endospores is a peptidoglycan (PG) wall. This wall is produced between the two opposed membranes surrounding the developing forespore and is composed of two layers. The inner layer is the germ cell wall, which appears to have a structure similar to that of the vegetative cell wall and which serves as the initial cell wall following spore germination. The outer layer, the cortex, has a modified structure, is required for maintenance of spore dehydration,...

  14. The Exosporium Layer of Bacterial Spores: a Connection to the Environment and the Infected Host

    OpenAIRE

    2015-01-01

    Much of what we know regarding bacterial spore structure and function has been learned from studies of the genetically well-characterized bacterium Bacillus subtilis. Molecular aspects of spore structure, assembly, and function are well defined. However, certain bacteria produce spores with an outer spore layer, the exosporium, which is not present on B. subtilis spores. Our understanding of the composition and biological functions of the exosporium layer is much more limited than that of oth...

  15. Genomics, evolution, and crystal structure of a new family of bacterial spore kinases

    OpenAIRE

    2009-01-01

    Bacterial spore formation is a complex process of fundamental relevance to biology and human disease. The spore coat structure is complex and poorly understood, and the roles of many of the protein components remain unclear. We describe a new family of spore coat proteins, the bacterial spore kinases (BSKs), and the first crystal structure of a BSK, YtaA (CotI) from Bacillus subtilis. BSKs are widely distributed in spore-forming Bacillus and Clostridium species, and have a dynamic evolutionar...

  16. Mechanisms of Induction of Germination of Bacillus subtilis Spores by High Pressure

    OpenAIRE

    Paidhungat, Madan; Setlow, Barbara; Daniels, William B.; Hoover, Dallas; Papafragkou, Efstathia; Setlow, Peter

    2002-01-01

    Spores of Bacillus subtilis lacking all germinant receptors germinate >500-fold slower than wild-type spores in nutrients and were not induced to germinate by a pressure of 100 MPa. However, a pressure of 550 MPa induced germination of spores lacking all germinant receptors as well as of receptorless spores lacking either of the two lytic enzymes essential for cortex hydrolysis during germination. Complete germination of spores either lacking both cortex-lytic enzymes or with a cortex not att...

  17. Quantification of Nonproteolytic Clostridium botulinum Spore Loads in Food Materials.

    Science.gov (United States)

    Barker, Gary C; Malakar, Pradeep K; Plowman, June; Peck, Michael W

    2016-01-04

    We have produced data and developed analysis to build representations for the concentration of spores of nonproteolytic Clostridium botulinum in materials that are used during the manufacture of minimally processed chilled foods in the United Kingdom. Food materials are categorized into homogenous groups which include meat, fish, shellfish, cereals, fresh plant material, dairy liquid, dairy nonliquid, mushroom and fungi, and dried herbs and spices. Models are constructed in a Bayesian framework and represent a combination of information from a literature survey of spore loads from positive-control experiments that establish a detection limit and from dedicated microbiological tests for real food materials. The detection of nonproteolytic C. botulinum employed an optimized protocol that combines selective enrichment culture with multiplex PCR, and the majority of tests on food materials were negative. Posterior beliefs about spore loads center on a concentration range of 1 to 10 spores kg(-1). Posterior beliefs for larger spore loads were most significant for dried herbs and spices and were most sensitive to the detailed results from control experiments. Probability distributions for spore loads are represented in a convenient form that can be used for numerical analysis and risk assessments.

  18. Availability of websites offering to sell psilocybin spores and psilocybin.

    Science.gov (United States)

    Lott, Jason P; Marlowe, Douglas B; Forman, Robert F

    2009-09-01

    This study assesses the availability of websites offering to sell psilocybin spores and psilocybin, a powerful hallucinogen contained in Psilocybe mushrooms. Over a 25-month period beginning in March 2003, eight searches were conducted in Google using the term "psilocybin spores." In each search the first 100 nonsponsored links obtained were scored by two independent raters according to standardized criteria to determine whether they offered to sell psilocybin or psilocybin spores. No attempts were made to procure the products offered for sale in order to ascertain whether the marketed psilocybin was in fact "genuine" or "counterfeit." Of the 800 links examined, 58% led to websites offering to sell psilocybin spores. Additionally, evidence that whole Psilocybe mushrooms are offered for sale online was obtained. Psilocybin and psilocybin spores were found to be widely available for sale over the Internet. Online purchase of psilocybin may facilitate illicit use of this potent psychoactive substance. Additional studies are needed to assess whether websites offering to sell psilocybin and psilocybin spores actually deliver their products as advertised.

  19. Small acid soluble proteins for rapid spore identification.

    Energy Technology Data Exchange (ETDEWEB)

    Branda, Steven S.; Lane, Todd W.; VanderNoot, Victoria A.; Jokerst, Amanda S.

    2006-12-01

    This one year LDRD addressed the problem of rapid characterization of bacterial spores such as those from the genus Bacillus, the group that contains pathogenic spores such as B. anthracis. In this effort we addressed the feasibility of using a proteomics based approach to spore characterization using a subset of conserved spore proteins known as the small acid soluble proteins or SASPs. We proposed developing techniques that built on our previous expertise in microseparations to rapidly characterize or identify spores. An alternative SASP extraction method was developed that was amenable to both the subsequent fluorescent labeling required for laser-induced fluorescence detection and the low ionic strength requirements for isoelectric focusing. For the microseparations, both capillary isoelectric focusing and chip gel electrophoresis were employed. A variety of methods were evaluated to improve the molecular weight resolution for the SASPs, which are in a molecular weight range that is not well resolved by the current methods. Isoelectric focusing was optimized and employed to resolve the SASPs using UV absorbance detection. Proteomic signatures of native wild type Bacillus spores and clones genetically engineered to produce altered SASP patterns were assessed by slab gel electrophoresis, capillary isoelectric focusing with absorbance detection as well as microchip based gel electrophoresis employing sensitive laser-induced fluorescence detection.

  20. Sterilization effect of UV light on Bacillus spores using TiO2 films depends on wavelength

    OpenAIRE

    Nhung, Le Thi Tuyet; Nagata, Hirofumi; Takahashi, Akira; Aihara, Mutsumi; Okamoto, Toshihiro; Shimohata, Takaaki; Mawatari, Kazuaki; Akutagawa, Masatake; Kinouchi, Yohsuke; Haraguchi, Masanobu

    2012-01-01

    UV light and photocatalysts such as titanium dioxide (TiO2) and silver (Ag) are useful for disinfection of water and surfaces. However, the effect of UV wavelength on photocatalytic disinfection of spores is not well understood. Inactivation of Bacillus spores has been examined using different UV wavelengths and TiO2 or TiO2/Ag composite materials. The level of UVA disinfection of Bacillus anthracis and Bacillus brevis vegetative cells increased with the presence of the TiO2 and Ag photocatal...

  1. Culturability of Bacillus spores on aerosol collection filters exposed to airborne combustion products of Al, Mg, and B·Ti.

    Science.gov (United States)

    Adhikari, Atin; Yermakov, Michael; Indugula, Reshmi; Reponen, Tiina; Driks, Adam; Grinshpun, Sergey A

    2016-05-01

    Destruction of bioweapon facilities due to explosion or fire could aerosolize highly pathogenic microorganisms. The post-event air quality assessment is conducted through air sampling. A bioaerosol sample (often collected on a filter for further culture-based analysis) also contains combustion products, which may influence the microbial culturability and, thus, impact the outcome. We have examined the interaction between spores deposited on collection filters using two simulants of Bacillus anthracis [B. thuringiensis (Bt) and B. atrophaeus (referred to as BG)] and incoming combustion products of Al as well as Mg and B·Ti (common ingredient of metalized explosives). Spores extracted from Teflon, polycarbonate, mixed cellulose ester (MCE), and gelatin filters (most common filter media for bioaerosol sampling), which were exposed to combustion products during a short-term sampling, were analyzed by cultivation. Surprisingly, we observed that aluminum combustion products enhanced the culturability of Bt (but not BG) spores on Teflon filters increasing the culturable count by more than an order of magnitude. Testing polycarbonate and MCE filter materials also revealed a moderate increase of culturability although gelatin did not. No effect was observed with either of the two species interacting on either filter media with products originated by combustion of Mg and B·Ti. Sample contamination, spore agglomeration, effect of a filter material on the spore survival, changes in the spore wall ultrastructure and germination, as well as other factors were explored to interpret the findings. The study raises a question about the reliability of certain filter materials for collecting airborne bio-threat agents in combustion environments.

  2. Synergistic effect of electrolyzed water and citric Acid against bacillus cereus cells and spores on cereal grains.

    Science.gov (United States)

    Park, Young Bae; Guo, Jin Yong; Rahman, S M E; Ahn, Juhee; Oh, Deog-Hwan

    2009-01-01

    The effects of acidic electrolyzed water (AcEW), alkaline electrolyzed water (AlEW), 100 ppm sodium hypochlorite (NaClO), and 1% citric acid (CA) alone, and combinations of AcEW with 1% CA (AcEW + CA) and AlEW with 1% CA (AlEW + CA) against Bacillus cereus vegetative cells and spores was evaluated as a function of temperature (25, 30, 40, 50, or 60 degrees C) and dipping time (3 or 6 h). A 3-strain cocktail of Bacillus cereus cells or spores of approximately 10(7) CFU/g was inoculated in various cereal grains (brown rice, Job's tear rice, glutinous rice, and barley rice). B. cereus vegetative cells and spores were more rapidly inactivated at 40 degrees C than at 25 degrees C. Regardless of the dipping time, all treatments reduced the numbers of B. cereus vegetative cells and spore by more than 1 log CFU/g, except the deionized water (DIW), which showed approximately 0.7 log reduction. The reductions of B. cereus cells increased with increasing dipping temperature (25 to 60 degrees C). B. cereus vegetative cells were much more sensitive to the combined treatments than spores. The effectiveness of the combined electrolyzed water (EW) and 1% CA was considerable in inhibiting B. cereus on cereal grains. The application of combined EW and CA for controlling B. cereus cells and spores on cereal grains has not been previously reported. Therefore, the synergistic effect of EW and CA may provide a valuable insight on reducing foodborne pathogens on fruits, vegetables, and cereal grains.

  3. Removal of pyrimidine dimers in UV-irradiated spores of Dictyostelium discoideum during germination

    Energy Technology Data Exchange (ETDEWEB)

    Okaichi, K.; Tano, K.; Ohnishi, T.; Nozu, K.

    1985-06-01

    The spores of Dictyostelium discoideum TW-8 (radC) are about twice as sensitive to UV than the parental strain NC-4 spores at a 10% survival level. Ultraviolet irradiation apparently suppressed the emergence of amoebae from swollen TW-8 spores as compared with NC-4 spores, though the conversion of spores into swollen spores was not affected by UV irradiation in either strain. About 85% removal of pyrimidine dimers was detected in UV-irradiated NC-4 spores at 200 J/m/sup 2/ during spore germination for 9 h, but no removal of pyrimidine dimers was detected in TW-8 spores under the same conditions. The removal of pyrimidine dimers from the NC-4 spores began at around 2 h germination when the spores have become swollen. The number of enzyme-sensitive sites (ESS) detected by Micrococcus luteus endonuclease in the DNA of UV-irradiated NC-4 spores also began to decrease at about 2 h into germination. The decrease in ESS, however, was hardly detectable in UV-irradiated TW-8 spores at any step during germination. Cycloheximide inhibited both decrease in the number of pyrimidine dimers, and decrease in the number of ESS of UV-irradiated NC-4 spores. It is suggested that UV-specific endonuclease is newly synthesized in swollen spores of NC-4. (author).

  4. National validation study of a swab protocol for the recovery of Bacillus anthracis spores from surfaces.

    Science.gov (United States)

    Hodges, Lisa R; Rose, Laura J; O'Connell, Heather; Arduino, Matthew J

    2010-05-01

    real-time PCR testing to the assay increased specificity from >85.4% to >95.0% in P2. Although the precision was low at the 1 log(10) inoculum level in both phases (59.0 and 50.2%), this swab processing protocol, was sensitive, specific, precise, and reproducible at 2-4 log(10)/26cm(2) spore concentrations.

  5. The impact of dose, irradiance and growth conditions on Aspergillus niger (renamed A. brasiliensis) spores low-pressure (LP) UV inactivation.

    Science.gov (United States)

    Taylor-Edmonds, Lizbeth; Lichi, Tovit; Rotstein-Mayer, Adi; Mamane, Hadas

    2015-01-01

    The use of Aspergillus niger (A. niger) fungal spores as challenge organism for UV reactor validation studies is attractive due to their high UV-resistance and non-pathogenic nature. However A. niger spores UV dose-response was dependent upon sporulation conditions and did not follow the Bunsen-Roscoe Principle of time-dose reciprocity. Exposure to 8 h of natural sunlight for 10 consecutive days increased UV resistance when compared to spores grown solely in dark conditions. Application of 250 mJ cm(-2) at high irradiance (0.11 mW cm(-2)) resulted in a 2-log inactivation; however, at low irradiance (0.022 mW cm(-2)) a 1-log inactivation was achieved. In addition, surface electron microscopy (SEM) images revealed morphological changes between the control and UV exposed spores in contrast to other well accepted UV calibrated test organisms, which show no morphological difference with UV exposure.

  6. [Effect on production of avermectins of spore pigment biosynthesis in Streptomyces avermitilis NRRL8165].

    Science.gov (United States)

    Zhu, Juanjuan; Tao, Meifeng

    2008-10-01

    The flanking fragments of the whiE(a) gene cluster was PCR amplified, cloned and used to construct the gene replacement plasmid pHL643. pHL643 was conjugated into Streptomyces avermitilis NRRL8165 followed by screening for double crossover event, yielding three apramycin resistance and thiostrepton sensitive isolates named ZJ1, ZJ2 and ZJ3, which were deficient in biosynthesis of the grey spore pigment. The whiE(a) gene replacement of these isolates was confirmed by Southern hybridization. Fermentation of the mutant strains in shaking flasks and HPLC analyses showed that the production of avermectins increased by 47% compared with that of the wild type, indicating that the spore pigment biosynthesis competes with the avermectins biosynthetic pathway.

  7. Heat-induced oxidative injury contributes to inhibition of Botrytis cinerea spore germination and growth.

    Science.gov (United States)

    Zhao, Wei; Wisniewski, Michael; Wang, Wenjie; Liu, Jia; Liu, Yongsheng

    2014-03-01

    The inhibitory effect of heat treatment (HT) on Botrytis cinerea, a major postharvest fungal pathogen, and the possible mode of action were investigated. Spore germination and germ tube elongation of B. cinerea were both increasingly and significantly inhibited by HT (43 °C) for 10, 20 or 30 min. HT-induced gene expression of NADPH oxidase A, resulted in the intracellular accumulation of reactive oxygen species. HT-treated B. cinerea spores exhibited higher levels of oxidative damage to proteins and lipids, compared to the non-HT control. These findings indicate that HT resulted in oxidative damage which then played an important role in the inhibitory effect on B. cinerea. In the current study, HT was effective in controlling gray mold, caused by B. cinerea, in pear fruits. Understanding the mode of action by which HT inhibits fungal pathogens will help in the application of HT for management of postharvest fungal diseases of fruits and vegetables.

  8. Application of nisin and pediocin against resistance and germination of Bacillus spores in sous vide products.

    Science.gov (United States)

    Cabo, M L; Torres, B; Herrera, J J R; Bernárdez, M; Pastoriza, L

    2009-03-01

    Sous vide and other mild preservation techniques are increasingly demanded by consumers. However, spores often will survive in minimally processed foods, causing both spoilage and safety problems. The main objective of the present work was to solve an industrial spoilage problem associated with two sous vide products: mushrooms and shellfish salad. Bacillus subtilis and Bacillus licheniformis predominated as the most heat-resistant organisms isolated from mushrooms and shellfish salad, respectively. The combined effects of nisin and pediocin against resistance and germination of both Bacillus species were described by empirical equations. Whereas nisin was more effective for decreasing thermal resistance of B. subtilis spores, pediocin was more effective against B. licheniformis. However, a significant positive interaction between both biopeptides for decreasing the proportion of vegetative cells resulting from thermoresistant spores was demonstrated in later experiments, thus indicating the increased efficacy of applying high concentrations of both bacteriocins. This efficacy was further demonstrated in additional challenge studies carried out at 15 degrees C in the two sous vide products: mushrooms and shellfish salad. Whereas no vegetative cells were detected after 90 days in the presence of bacteriocins, almost 100% of the population in nontreated samples of mushrooms and shellfish salad was in the vegetative state after 17 and 43 days of storage at 15 degrees C, respectively.

  9. Fungal Spores Viability on the International Space Station.

    Science.gov (United States)

    Gomoiu, I; Chatzitheodoridis, E; Vadrucci, S; Walther, I; Cojoc, R

    2016-11-01

    In this study we investigated the security of a spaceflight experiment from two points of view: spreading of dried fungal spores placed on the different wafers and their viability during short and long term missions on the International Space Station (ISS). Microscopic characteristics of spores from dried spores samples were investigated, as well as the morphology of the colonies obtained from spores that survived during mission. The selected fungal species were: Aspergillus niger, Cladosporium herbarum, Ulocladium chartarum, and Basipetospora halophila. They have been chosen mainly based on their involvement in the biodeterioration of different substrate in the ISS as well as their presence as possible contaminants of the ISS. From biological point of view, three of the selected species are black fungi, with high melanin content and therefore highly resistant to space radiation. The visual inspection and analysis of the images taken before and after the short and the long term experiments have shown that all biocontainers were returned to Earth without damages. Microscope images of the lids of the culture plates revealed that the spores of all species were actually not detached from the surface of the wafers and did not contaminate the lids. From the adhesion point of view all types of wafers can be used in space experiments, with a special comment on the viability in the particular case of iron wafers when used for spores that belong to B. halophila (halophilic strain). This is encouraging in performing experiments with fungi without risking contamination. The spore viability was lower in the experiment for long time to ISS conditions than that of the short experiment. From the observations, it is suggested that the environment of the enclosed biocontainer, as well as the species'specific behaviour have an important effect, reducing the viability in time. Even the spores were not detached from the surface of the wafers, it was observed that spores used in the

  10. Fungal Spores Viability on the International Space Station

    Science.gov (United States)

    Gomoiu, I.; Chatzitheodoridis, E.; Vadrucci, S.; Walther, I.; Cojoc, R.

    2016-04-01

    In this study we investigated the security of a spaceflight experiment from two points of view: spreading of dried fungal spores placed on the different wafers and their viability during short and long term missions on the International Space Station (ISS). Microscopic characteristics of spores from dried spores samples were investigated, as well as the morphology of the colonies obtained from spores that survived during mission. The selected fungal species were: Aspergillus niger, Cladosporium herbarum, Ulocladium chartarum, and Basipetospora halophila. They have been chosen mainly based on their involvement in the biodeterioration of different substrate in the ISS as well as their presence as possible contaminants of the ISS. From biological point of view, three of the selected species are black fungi, with high melanin content and therefore highly resistant to space radiation. The visual inspection and analysis of the images taken before and after the short and the long term experiments have shown that all biocontainers were returned to Earth without damages. Microscope images of the lids of the culture plates revealed that the spores of all species were actually not detached from the surface of the wafers and did not contaminate the lids. From the adhesion point of view all types of wafers can be used in space experiments, with a special comment on the viability in the particular case of iron wafers when used for spores that belong to B. halophila (halophilic strain). This is encouraging in performing experiments with fungi without risking contamination. The spore viability was lower in the experiment for long time to ISS conditions than that of the short experiment. From the observations, it is suggested that the environment of the enclosed biocontainer, as well as the species'specific behaviour have an important effect, reducing the viability in time. Even the spores were not detached from the surface of the wafers, it was observed that spores used in the

  11. Fungal Spores Viability on the International Space Station

    Science.gov (United States)

    Gomoiu, I.; Chatzitheodoridis, E.; Vadrucci, S.; Walther, I.; Cojoc, R.

    2016-11-01

    In this study we investigated the security of a spaceflight experiment from two points of view: spreading of dried fungal spores placed on the different wafers and their viability during short and long term missions on the International Space Station (ISS). Microscopic characteristics of spores from dried spores samples were investigated, as well as the morphology of the colonies obtained from spores that survived during mission. The selected fungal species were: Aspergillus niger, Cladosporium herbarum, Ulocladium chartarum, and Basipetospora halophila. They have been chosen mainly based on their involvement in the biodeterioration of different substrate in the ISS as well as their presence as possible contaminants of the ISS. From biological point of view, three of the selected species are black fungi, with high melanin content and therefore highly resistant to space radiation. The visual inspection and analysis of the images taken before and after the short and the long term experiments have shown that all biocontainers were returned to Earth without damages. Microscope images of the lids of the culture plates revealed that the spores of all species were actually not detached from the surface of the wafers and did not contaminate the lids. From the adhesion point of view all types of wafers can be used in space experiments, with a special comment on the viability in the particular case of iron wafers when used for spores that belong to B. halophila (halophilic strain). This is encouraging in performing experiments with fungi without risking contamination. The spore viability was lower in the experiment for long time to ISS conditions than that of the short experiment. From the observations, it is suggested that the environment of the enclosed biocontainer, as well as the species'specific behaviour have an important effect, reducing the viability in time. Even the spores were not detached from the surface of the wafers, it was observed that spores used in the

  12. Challenges and advances in systems biology analysis of Bacillus spore physiology; molecular differences between an extreme heat resistant spore forming Bacillus subtilis food isolate and a laboratory strain

    NARCIS (Netherlands)

    Brul, S.; van Beilen, J.; Caspers, M.; O'Brien, A.; de Koster, C.; Oomes, S.; Smelt, J.; Kort, R.; ter Beek, A.

    2011-01-01

    Bacterial spore formers are prime organisms of concern in the food industry. Spores from the genus Bacillus are extremely stress resistant, most notably exemplified by high thermotolerance. This sometimes allows surviving spores to germinate and grow out to vegetative cells causing food spoilage and

  13. Inflammatory potential of the spores of Penicillium spinulosum isolated from indoor air of a moisture-damaged building in mouse lungs.

    Science.gov (United States)

    Jussila, Juha; Komulainen, Hannu; Kosma, Veli-Matti; Pelkonen, Jukka; Hirvonen, Maija-Riitta

    2002-10-01

    Excess moisture and microbial growth have been associated with adverse health effects, especially in the airways, of the inhabitants of moisture-damaged buildings. The spores of Penicillium spp. are commonly present in the indoor air, both in moisture-damaged and in reference buildings, though their numbers seem to be significantly higher in the damaged buildings. To assess the potential of Penicillium spinulosum to evoke harmful respiratory effects, mice were exposed via intratracheal instillation to a single dose of the spores of P. spinulosum, isolated from the indoor air of a moisture-damaged building (1×10(5), 1×10(6), 5×10(6), 1×10(7) or 5×10(7) spores). Inflammation and toxicity in lungs were evaluated 24 h later. The time-course of the effects was investigated with the dose of 5×10(6) spores for 28 days. The fungal spores caused mild transient inflammation. The spore exposure transiently increased proinflammatory cytokine (TNFα and IL-6) levels in bronchoalveolar lavage fluid (BALF) in a dose- and time-dependent manner. The highest concentrations of both cytokines were measured at 6 h after a single dosage. The spore exposure did not cause expression of inducible nitric oxide synthase in lavaged cells. Neutrophils were acutely recruited into airways, but the response leveled off in 3 days. Neither cytotoxicity nor major changes in vascular permeability (i.e. increases in albumin, total protein, lactate dehydrogenase or hemoglobin levels in BALF) were observed in the lungs. Considering the profile and magnitude of the changes and the dose of the spores, we conclude that P. spinulosum has a low potential to cause acute respiratory inflammation, nor does it cause direct cytotoxicity.

  14. Characterization of Bacillus sporothermodurans IC4 spores; putative indicator microorganism for optimisation of thermal processes in food sterilisation

    NARCIS (Netherlands)

    van Zuijlen, A.; Periago, P.M.; Amézquita, A.; Palop, A.; Brul, S.; Fernández, P.S.

    2010-01-01

    Spore-forming bacteria with high heat resistance increasingly challenge industrial sterilisation processes in foods. To ensure stability of manufactured foods, generally worst case scenarios are applied often leading to unwanted over processing of foods. This means bigger requirements of energy and

  15. Spore population, colonization, species diversity and factors influencing the association of arbuscular mycorrhizal fungi with litchi trees in India.

    Science.gov (United States)

    Kumar, Vinod; Kumar, Rajesh; Kumar, Ajit; Anal, Dubedi

    2016-01-01

    Abundance and diversity of arbuscular mycorrhizal fungi (AMF) in association with litchi (Litchi chinensis Sonn.) trees were studied during 2012-2013, where orchard soil had high pH (7.42-9.53) and salinity (0.07- 0.39 dSm(-1)). A total of 105 rhizospheric soil and root samples were collected considering variables like location, age of tree, cultivar and production management. Results showed that spore count was in the range of 1-22 g(-1) soil. All the examined root segments had colonization of AMF, which ranged between 3.3 to 90.0%. AMF community comprised of Glomus mosseae, G. intaradices, G. constricta, G. coronatum, G. fasciculatum, G. albidum, G. hoi, G. multicauli, Acaulospora scrobiculata, A. laevis, Rhizophagus litchi and Entrophosphora infrequens. Higher spore density and AMF colonization were observed at medium level (13-28 kg ha(-1)) of available phosphorus that decreased ('r' = -0.21 for spore density, -0.48 for root colonization) with increasing soil phosphorus. While nitrogen did not influence the AMF association, a weak negative linear relationship with AMF colonization ('r' = -0.30) was apparent in the medium level (112-200 kg ha(-1)) of potash. Micronutrients (Zn, Fe, Cu, Mn and B) did not affect spore density (zero or a very weak linear correlation) but influenced root colonization ('r' = -0.53 to -0.44), the effect being more prominent above critical limits. Nutritionally sufficient, irrigated litchi orchards had greater spore count (46% samples having 5-22 spores g(-1) soil) and colonization (> 50% in 37.4% roots examined) than nutrient deficient, non-irrigated orchards, indicating essentiality of a threshold nutrients and moisture regime for the association. AMF symbiosis was influenced by cultivar (greater in 'China'), but tree age was not correlated to mycorrhizal association. A consortium of native species coupled with the understanding of nutrient effects on AMF would be useful for field application in litchi.

  16. The Fate of the Missing Spores — Patterns of Realized Dispersal beyond the Closest Vicinity of a Sporulating Moss

    Science.gov (United States)

    Lönnell, Niklas; Hylander, Kristoffer; Jonsson, Bengt Gunnar; Sundberg, Sebastian

    2012-01-01

    It is well-known that many species with small diaspores can disperse far during extended temporal scales (many years). However, studies on short temporal scales usually only cover short distances (in, e.g., bryophytes up to 15 m). By using a novel experimental design, studying the realized dispersal, we extend this range by almost two orders of magnitude. We recorded establishment of the fast-growing moss Discelium nudum on introduced suitable substrates, placed around a translocated, sporulating mother colony. Around 2,000 pots with acidic clay were placed at different distances between 5 m and 600 m, in four directions, on a raised bog, with increased pot numbers with distance. The experiment was set up in April–May and the realized dispersal (number of colonized pots) was recorded in September. Close to the mother colony (up to 10 m), the mean colonization rates (ratio of colonized pots) exceeded 50%. At distances between 10 and 50 m colonization dropped sharply, but beyond 50 m the mean colonization rates stabilized and hardly changed (1–3%). The estimated density of spores causing establishments at the further distances (2–6 spores/m2) was realistic when compared to the estimated spore output from the central colonies. Our study supports calculations from earlier studies, limited to short distances, that a majority of the spores disperse beyond the nearest vicinity of a source. The even colonization pattern at further distances raises interesting questions about under what conditions spores are transported and deposited. However, it is clear that regular establishment is likely at the km-scale for this and many other species with similar spore output and dispersal mechanism. PMID:22870183

  17. The fate of the missing spores--patterns of realized dispersal beyond the closest vicinity of a sporulating moss.

    Science.gov (United States)

    Lönnell, Niklas; Hylander, Kristoffer; Jonsson, Bengt Gunnar; Sundberg, Sebastian

    2012-01-01

    It is well-known that many species with small diaspores can disperse far during extended temporal scales (many years). However, studies on short temporal scales usually only cover short distances (in, e.g., bryophytes up to 15 m). By using a novel experimental design, studying the realized dispersal, we extend this range by almost two orders of magnitude. We recorded establishment of the fast-growing moss Discelium nudum on introduced suitable substrates, placed around a translocated, sporulating mother colony. Around 2,000 pots with acidic clay were placed at different distances between 5 m and 600 m, in four directions, on a raised bog, with increased pot numbers with distance. The experiment was set up in April-May and the realized dispersal (number of colonized pots) was recorded in September. Close to the mother colony (up to 10 m), the mean colonization rates (ratio of colonized pots) exceeded 50%. At distances between 10 and 50 m colonization dropped sharply, but beyond 50 m the mean colonization rates stabilized and hardly changed (1-3%). The estimated density of spores causing establishments at the further distances (2-6 spores/m²) was realistic when compared to the estimated spore output from the central colonies. Our study supports calculations from earlier studies, limited to short distances, that a majority of the spores disperse beyond the nearest vicinity of a source. The even colonization pattern at further distances raises interesting questions about under what conditions spores are transported and deposited. However, it is clear that regular establishment is likely at the km-scale for this and many other species with similar spore output and dispersal mechanism.

  18. The fate of the missing spores--patterns of realized dispersal beyond the closest vicinity of a sporulating moss.

    Directory of Open Access Journals (Sweden)

    Niklas Lönnell

    Full Text Available It is well-known that many species with small diaspores can disperse far during extended temporal scales (many years. However, studies on short temporal scales usually only cover short distances (in, e.g., bryophytes up to 15 m. By using a novel experimental design, studying the realized dispersal, we extend this range by almost two orders of magnitude. We recorded establishment of the fast-growing moss Discelium nudum on introduced suitable substrates, placed around a translocated, sporulating mother colony. Around 2,000 pots with acidic clay were placed at different distances between 5 m and 600 m, in four directions, on a raised bog, with increased pot numbers with distance. The experiment was set up in April-May and the realized dispersal (number of colonized pots was recorded in September. Close to the mother colony (up to 10 m, the mean colonization rates (ratio of colonized pots exceeded 50%. At distances between 10 and 50 m colonization dropped sharply, but beyond 50 m the mean colonization rates stabilized and hardly changed (1-3%. The estimated density of spores causing establishments at the further distances (2-6 spores/m² was realistic when compared to the estimated spore output from the central colonies. Our study supports calculations from earlier studies, limited to short distances, that a majority of the spores disperse beyond the nearest vicinity of a source. The even colonization pattern at further distances raises interesting questions about under what conditions spores are transported and deposited. However, it is clear that regular establishment is likely at the km-scale for this and many other species with similar spore output and dispersal mechanism.

  19. Effect of Essential Oils on Germination and Growth of Some Pathogenic and Spoilage Spore-Forming Bacteria.

    Science.gov (United States)

    Voundi, Stève Olugu; Nyegue, Maximilienne; Lazar, Iuliana; Raducanu, Dumitra; Ndoye, Florentine Foe; Marius, Stamate; Etoa, François-Xavier

    2015-06-01

    The use of essential oils as a food preservative has increased due to their capacity to inhibit vegetative growth of some bacteria. However, only limited data are available on their effect on bacterial spores. The aim of the present study was to evaluate the effect of some essential oils on the growth and germination of three Bacillus species and Geobacillus stearothermophilus. Essential oils were chemically analyzed using gas chromatography and gas chromatography coupled to mass spectrometry. The minimal inhibitory and bactericidal concentrations of vegetative growth and spore germination were assessed using the macrodilution method. Germination inhibitory effect of treated spores with essential oils was evaluated on solid medium, while kinetic growth was followed using spectrophotometry in the presence of essential oils. Essential oil from Drypetes gossweileri mainly composed of benzyl isothiocyanate (86.7%) was the most potent, with minimal inhibitory concentrations ranging from 0.0048 to 0.0097 mg/mL on vegetative cells and 0.001 to 0.002 mg/mL on spore germination. Furthermore, essential oil from D. gossweileri reduced 50% of spore germination after treatment at 1.25 mg/mL, and its combination with other oils improved both bacteriostatic and bactericidal activities with additive or synergistic effects. Concerning the other essential oils, the minimal inhibitory concentration ranged from 5 to 0.63 mg/mL on vegetative growth and from 0.75 to 0.09 mg/mL on the germination of spores. Spectrophotometric evaluation showed an inhibitory effect of essential oils on both germination and outgrowth. From these results, it is concluded that some of the essential oils tested might be a valuable tool for bacteriological control in food industries. Therefore, further research regarding their use as food preservatives should be carried out.

  20. Viable spore counts in biological controls pre-sterilization.

    Science.gov (United States)

    Brusca, María I; Bernat, María I; Turcot, Liliana; Nastri, Natalia; Nastri, Maria; Rosa, Alcira

    2005-01-01

    The aim of the present study was to evaluate the total count of viable spores in standardized inoculated carriers pre-sterilization. Samples of "Bacterial Spore Sterilization Strip" (R Biological Laboratories) (well before their expiry date) were divided into Group A (B. subtilis) and Group B (B. stearothermophylus). Twenty-four strips were tested per group. The strips were minced in groups of three, placed in chilled sterile water and vortexed for 5 minutes to obtain a homogenous suspension. Ten ml of the homogenous suspension were transferred to two sterile jars, i.e. one jar per group. The samples were then heated in a water bath at 95 degrees C (Group A) or 80 degrees C (Group B) for 15 minutes and cooled rapidly in an ice bath at 0- 4 degrees C during 15 minutes. Successive dilutions were performed until a final aliquot of 30 to 300 colony-forming units (CFU) was obtained. The inoculums were placed in Petri dishes with culture medium (soy extract, casein agar adapted for spores, melted and cooled to 45-50 degrees C) and incubated at 55 degrees C or 37 degrees C. Statistical analysis of the data was performed. A larger number of spores were found at 48 hours than at 24 hours. However, this finding did not hold true for all the groups. The present results show that monitoring viable spores pre-sterilization would guarantee the accuracy of the data. Total spore counts must be within 50 and 300% of the number of spores indicated in the biological control. The procedure is essential to guarantee the efficacy of the biological control.

  1. The Exosporium Layer of Bacterial Spores: a Connection to the Environment and the Infected Host.

    Science.gov (United States)

    Stewart, George C

    2015-12-01

    Much of what we know regarding bacterial spore structure and function has been learned from studies of the genetically well-characterized bacterium Bacillus subtilis. Molecular aspects of spore structure, assembly, and function are well defined. However, certain bacteria produce spores with an outer spore layer, the exosporium, which is not present on B. subtilis spores. Our understanding of the composition and biological functions of the exosporium layer is much more limited than that of other aspects of the spore. Because the bacterial spore surface is important for the spore's interactions with the environment, as well as being the site of interaction of the spore with the host's innate immune system in the case of spore-forming bacterial pathogens, the exosporium is worthy of continued investigation. Recent exosporium studies have focused largely on members of the Bacillus cereus family, principally Bacillus anthracis and Bacillus cereus. Our understanding of the composition of the exosporium, the pathway of its assembly, and its role in spore biology is now coming into sharper focus. This review expands on a 2007 review of spore surface layers which provided an excellent conceptual framework of exosporium structure and function (A. O. Henriques and C. P. Moran, Jr., Annu Rev Microbiol 61:555-588, 2007, http://dx.doi.org/10.1146/annurev.micro.61.080706.093224). That review began a process of considering outer spore layers as an integrated, multilayered structure rather than simply regarding the outer spore components as independent parts.

  2. At-line determining spore germination of Penicillium chrysogenum bioprocesses in complex media.

    Science.gov (United States)

    Ehgartner, Daniela; Fricke, Jens; Schröder, Andreas; Herwig, Christoph

    2016-10-01

    Spore inoculum quality in filamentous bioprocesses is a critical parameter associated with viable spore concentration (1) and spore germination (2). It influences pellet morphology and, consequently, process performance. The state-of-the-art method to measure viable spore concentration is tedious, associated with significant inherent bias, and not applicable in real-time. Therefore, it is not usable as process analytical technology (PAT). Spore germination has so far been monitored using image analysis, which is hampered by complex medium background often observed in filamentous bioprocesses. The method presented here is based on the combination of viability staining and large-particle flow cytometry which enables measurements in real-time and hence aims to be applicable as a PAT tool. It is compatible with the complex media background and allows the quantification of metabolically active spores and the monitoring of spore germination. A distinction of germinated spores and not germinated spores was based on logistic regression, using multiparameteric data from flow cytometry. In a first step, a significant correlation between colony-forming unit (CFU) counts and viable spore concentration (1) in an industrially relevant model bioprocess was found. Spore germination (2) was followed over the initial process phase with close temporal resolution. The validation of the method showed an error below 5 %. Differences in spore germination for various spore inocula ages and spore inoculum concentrations were monitored. The real-time applicability of the method suggests the implementation as a PAT tool in filamentous bioprocesses.

  3. Graphene quantum dots interfaced with single bacterial spore for bio-electromechanical devices: a graphene cytobot.

    Science.gov (United States)

    Sreeprasad, T S; Nguyen, Phong; Alshogeathri, Ahmed; Hibbeler, Luke; Martinez, Fabian; McNeil, Nolan; Berry, Vikas

    2015-03-16

    The nanoarchitecture and micromachinery of a cell can be leveraged to fabricate sophisticated cell-driven devices. This requires a coherent strategy to derive cell's mechanistic abilities, microconstruct, and chemical-texture towards such microtechnologies. For example, a microorganism's hydrophobic membrane encapsulating hygroscopic constituents allows it to sustainably withhold a high aquatic pressure. Further, it provides a rich surface chemistry available for nano-interfacing and a strong mechanical response to humidity. Here we demonstrate a route to incorporate a complex cellular structure into microelectromechanics by interfacing compatible graphene quantum dots (GQDs) with a highly responsive single spore microstructure. A sensitive and reproducible electron-tunneling width modulation of 1.63 nm within a network of GQDs chemically-secured on a spore was achieved via sporal hydraulics with a driving force of 299.75 Torrs (21.7% water at GQD junctions). The electron-transport activation energy and the Coulomb blockade threshold for the GQD network were 35 meV and 31 meV, respectively; while the inter-GQD capacitance increased by 1.12 folds at maximum hydraulic force. This is the first example of nano/bio interfacing with spores and will lead to the evolution of next-generation bio-derived microarchitectures, probes for cellular/biochemical processes, biomicrorobotic-mechanisms, and membranes for micromechanical actuation.

  4. Graphene Quantum Dots Interfaced with Single Bacterial Spore for Bio-Electromechanical Devices: A Graphene Cytobot

    Science.gov (United States)

    Sreeprasad, T. S.; Nguyen, Phong; Alshogeathri, Ahmed; Hibbeler, Luke; Martinez, Fabian; McNeil, Nolan; Berry, Vikas

    2015-03-01

    The nanoarchitecture and micromachinery of a cell can be leveraged to fabricate sophisticated cell-driven devices. This requires a coherent strategy to derive cell's mechanistic abilities, microconstruct, and chemical-texture towards such microtechnologies. For example, a microorganism's hydrophobic membrane encapsulating hygroscopic constituents allows it to sustainably withhold a high aquatic pressure. Further, it provides a rich surface chemistry available for nano-interfacing and a strong mechanical response to humidity. Here we demonstrate a route to incorporate a complex cellular structure into microelectromechanics by interfacing compatible graphene quantum dots (GQDs) with a highly responsive single spore microstructure. A sensitive and reproducible electron-tunneling width modulation of 1.63 nm within a network of GQDs chemically-secured on a spore was achieved via sporal hydraulics with a driving force of 299.75 Torrs (21.7% water at GQD junctions). The electron-transport activation energy and the Coulomb blockade threshold for the GQD network were 35 meV and 31 meV, respectively; while the inter-GQD capacitance increased by 1.12 folds at maximum hydraulic force. This is the first example of nano/bio interfacing with spores and will lead to the evolution of next-generation bio-derived microarchitectures, probes for cellular/biochemical processes, biomicrorobotic-mechanisms, and membranes for micromechanical actuation.

  5. Differential Inactivation of Fungal Spores in Water and on Seeds by Ozone and Arc Discharge Plasma.

    Directory of Open Access Journals (Sweden)

    Min Ho Kang

    Full Text Available Seed sterilization is essential for preventing seed borne fungal diseases. Sterilization tools based on physical technologies have recently received much attention. However, available information is very limited in terms of efficiency, safety, and mode of action. In this study, we have examined antifungal activity of ozone and arc discharge plasma, potential tools for seed sterilization. In our results, ozone and arc discharge plasma have shown differential antifungal effects, depending on the environment associated with fungal spores (freely submerged in water or infected seeds. Ozone inactivates Fusarium fujikuroi (fungus causing rice bakanae disease spores submerged in water more efficiently than arc discharge plasma. However, fungal spores associated with or infecting rice seeds are more effectively deactivated by arc discharge plasma. ROS generated in water by ozone may function as a powerful fungicidal factor. On the other hand, shockwave generated from arc discharge plasma may have greatly contributed to antifungal effects on fungus associated with rice seeds. In support of this notion, addition of ultrasonic wave in ozone generating water has greatly increased the efficiency of seed disinfection.

  6. Differential Inactivation of Fungal Spores in Water and on Seeds by Ozone and Arc Discharge Plasma

    Science.gov (United States)

    Kang, Min Ho; Pengkit, Anchalee; Choi, Kihong; Jeon, Seong Sil; Choi, Hyo Won; Shin, Dong Bum; Choi, Eun Ha; Uhm, Han Sup; Park, Gyungsoon

    2015-01-01

    Seed sterilization is essential for preventing seed borne fungal diseases. Sterilization tools based on physical technologies have recently received much attention. However, available information is very limited in terms of efficiency, safety, and mode of action. In this study, we have examined antifungal activity of ozone and arc discharge plasma, potential tools for seed sterilization. In our results, ozone and arc discharge plasma have shown differential antifungal effects, depending on the environment associated with fungal spores (freely submerged in water or infected seeds). Ozone inactivates Fusarium fujikuroi (fungus causing rice bakanae disease) spores submerged in water more efficiently than arc discharge plasma. However, fungal spores associated with or infecting rice seeds are more effectively deactivated by arc discharge plasma. ROS generated in water by ozone may function as a powerful fungicidal factor. On the other hand, shockwave generated from arc discharge plasma may have greatly contributed to antifungal effects on fungus associated with rice seeds. In support of this notion, addition of ultrasonic wave in ozone generating water has greatly increased the efficiency of seed disinfection. PMID:26406468

  7. Relationship of the syntheses of spore coat protein and parasporal crystal protein in Bacillus thuringiensis.

    Science.gov (United States)

    Aronson, A I; Tyrell, D J; Fitz-James, P C; Bulla, L A

    1982-01-01

    Two major classes of polypeptides were extracted from the spore surface of Bacillus thuringiensis subsp. kurstaki: the 134,000-dalton protoxin that is the major component of the crystalline inclusion and spore coat polypeptides very similar to those found on Bacillus cereus spores. The quantity of spore coat polypeptides produced was reduced when compared with that produced by certain acrystalliferous mutants or by B. thuringiensis subsp. israelensis. The latter organism produced an inclusion toxic to mosquito larvae, but deposited very little of the inclusion protein on the spore surface. The reduction in spore coat protein in B. thuringiensis subsp. kurstaki was also seen in freeze-etched electron micrographs of spores. B. thuringiensis subsp. kurstaki spores germinated rather slowly when compared with related species, a property previously correlated with a deficiency or defect of the spore coat. Many mutants of B. thuringiensis subsp. kurstaki unable to form a crystalline inclusion were nontoxic and lacked a well-defined spore coat. Other mutants isolated either directly from the wild type or from coat-deficient mutants produced spores that were identical to those produced by the closely related species. Bacillus cereus, on the basis of morphology, germination rate, and the size and antigenicity of the spore coat polypeptides. Most of the protein extractable from the inclusion produced by B. thuringiensis subsp. israelensis was about 26,000 daltons, considerably smaller than the major polypeptide extractable from other inclusions. Some of the B. thuringiensis subsp. israelensis inclusion protein was found on the spore surface, but the majority of the extractable spore coat protein was the same size and antigenicity as that found on B. cereus spores. The B. thuringiensis subsp. israelensis spores germinated at a rate close to that of B. cereus, especially when the spores were formed at 37 degrees C, and the morphology of the spore surface was very similar to

  8. Fighting Ebola with novel spore decontamination technologies for the military.

    Science.gov (United States)

    Doona, Christopher J; Feeherry, Florence E; Kustin, Kenneth; Olinger, Gene G; Setlow, Peter; Malkin, Alexander J; Leighton, Terrance

    2015-01-01

    Recently, global public health organizations such as Doctors without Borders (MSF), the World Health Organization (WHO), Public Health Canada, National Institutes of Health (NIH), and the U.S. government developed and deployed Field Decontamination Kits (FDKs), a novel, lightweight, compact, reusable decontamination technology to sterilize Ebola-contaminated medical devices at remote clinical sites lacking infra-structure in crisis-stricken regions of West Africa (medical waste materials are placed in bags and burned). The basis for effectuating sterilization with FDKs is chlorine dioxide (ClO2) produced from a patented invention developed by researchers at the US Army Natick Soldier RD&E Center (NSRDEC) and commercialized as a dry mixed-chemical for bacterial spore decontamination. In fact, the NSRDEC research scientists developed an ensemble of ClO2 technologies designed for different applications in decontaminating fresh produce; food contact and handling surfaces; personal protective equipment; textiles used in clothing, uniforms, tents, and shelters; graywater recycling; airplanes; surgical instruments; and hard surfaces in latrines, laundries, and deployable medical facilities. These examples demonstrate the far-reaching impact, adaptability, and versatility of these innovative technologies. We present herein the unique attributes of NSRDEC's novel decontamination technologies and a Case Study of the development of FDKs that were deployed in West Africa by international public health organizations to sterilize Ebola-contaminated medical equipment. FDKs use bacterial spores as indicators of sterility. We review the properties and structures of spores and the mechanisms of bacterial spore inactivation by ClO2. We also review mechanisms of bacterial spore inactivation by novel, emerging, and established non-thermal technologies for food preservation, such as high pressure processing, irradiation, cold plasma, and chemical sanitizers, using an array of Bacillus

  9. Fighting Ebola with novel spore decontamination technologies for the military

    Science.gov (United States)

    Doona, Christopher J.; Feeherry, Florence E.; Kustin, Kenneth; Olinger, Gene G.; Setlow, Peter; Malkin, Alexander J.; Leighton, Terrance

    2015-01-01

    Recently, global public health organizations such as Doctors without Borders (MSF), the World Health Organization (WHO), Public Health Canada, National Institutes of Health (NIH), and the U.S. government developed and deployed Field Decontamination Kits (FDKs), a novel, lightweight, compact, reusable decontamination technology to sterilize Ebola-contaminated medical devices at remote clinical sites lacking infra-structure in crisis-stricken regions of West Africa (medical waste materials are placed in bags and burned). The basis for effectuating sterilization with FDKs is chlorine dioxide (ClO2) produced from a patented invention developed by researchers at the US Army Natick Soldier RD&E Center (NSRDEC) and commercialized as a dry mixed-chemical for bacterial spore decontamination. In fact, the NSRDEC research scientists developed an ensemble of ClO2 technologies designed for different applications in decontaminating fresh produce; food contact and handling surfaces; personal protective equipment; textiles used in clothing, uniforms, tents, and shelters; graywater recycling; airplanes; surgical instruments; and hard surfaces in latrines, laundries, and deployable medical facilities. These examples demonstrate the far-reaching impact, adaptability, and versatility of these innovative technologies. We present herein the unique attributes of NSRDEC’s novel decontamination technologies and a Case Study of the development of FDKs that were deployed in West Africa by international public health organizations to sterilize Ebola-contaminated medical equipment. FDKs use bacterial spores as indicators of sterility. We review the properties and structures of spores and the mechanisms of bacterial spore inactivation by ClO2. We also review mechanisms of bacterial spore inactivation by novel, emerging, and established non-thermal technologies for food preservation, such as high pressure processing, irradiation, cold plasma, and chemical sanitizers, using an array of Bacillus

  10. Genotoxic evaluation in Oreochromis niloticus (Fish: Characidae) of recombinant spore-crystal complexes Cry1Ia, Cry10Aa and Cry1Ba6 from Bacillus thuringiensis.

    Science.gov (United States)

    Freire, I S; Miranda-Vilela, A L; Fascineli, M L; Oliveira-Filho, E C; Martins, E S; Monnerat, R G; Grisolia, C K

    2014-03-01

    Bioinsecticides from Bacillus thuringiensis (Bt) are widely used around the world in biological control against larval stages of many insect species. Bt has been considered a biopesticide that is highly specific to different orders of insects, non-polluting and harmless to humans and other vertebrates, thus becoming a viable alternative for combating agricultural pests and insect vectors of diseases. The family of Bt δ-endotoxins are crystal-protein inclusions showing toxicity to insects' midgut, causing cell lysis leading to starvation, septicemia and death. The aim of this study is to evaluate the genotoxic potential of recombinant Bt spore-crystals expressing Cry1Ia, Cry10Aa and Cry1Ba6 on peripheral erythrocyte cells of Oreochromis niloticus, through comet assay, micronucleus (MN) test and nuclear abnormalities (NA) analysis. Fish (n = 10/group) were exposed for 96 h at 10(7) spores 30 l(-1), 10(8) spores 30 l(-1) or 10(9) spores 30 l(-1) of Bt spore-crystals. Cry1Ia showed a significant increase in comet cells at levels 1 and 2, but not at levels 3 and 4, so it was not mutagenic nor did it induce MN or NA. These three spore-crystals showed some fish toxicity at only the highest exposure level, which normally does not occur in the field.

  11. STREPTOMYCES SPECIES COMPRISING THE BLUE-SPORE SERIES.

    Science.gov (United States)

    TREJO, W H; BENNETT, R E

    1963-03-01

    Trejo, W. H. (Squibb Institute for Medical Research, New Brunswick, N.J.) and R. E. Bennett. Streptomyces species comprising the blue-spore series. J. Bacteriol. 85:676-690. 1963.-The objective of this study was to define and delimit the streptomycetes of the blue-spored (Viridochromogenes) series. The series, as defined in this study, includes 11 blue and blue-green species. The green-spored species were excluded on the basis of morphology as well as color. It was proposed that NRRL B-1511 be designated as the neotype strain of Streptomyces viridochromogenes (Krainsky) Waksman and Henrici, and that IMRU 3761 be designated as the neotype for Streptomyces cyaneus (Krassilnikov) Waksman. Evidence was presented to show that physiological criteria cannot be used to differentiate these organisms below the series level. The major characteristics of the Viridochromogenes series are blue to blue-green spores borne in spirals, and chromogenicity (melanin-positive). Reverse color and spore morphology provide a basis for separation below the series level.

  12. Bacillus globigii bugbeads: a model simulant of a bacterial spore.

    Science.gov (United States)

    Farrell, Svetlana; Halsall, H Brian; Heineman, William R

    2005-01-15

    Nonpathogenic microorganisms are often used as simulants of biological pathogens during the initial phase of detection method development. While these simulants approximate the size, shape, and cellular organization of the microorganism of interest, they do not resemble its surface protein content, a factor particularly important in methods based on immunorecognition. Here, we develop and detect an artificial bacterial spore--B. globigii (BG) Bugbead-a particle mimicking the antigenic surface of BG spores. Two methods of spore protein extraction were compared both quantitatively (by protein concentration assay) and qualitatively (by SDS-PAGE and Western blot): extraction by mechanical disruption and extraction by chemical decoating. The former method was more efficient in producing more protein and a greater number of antigens. BG Bugbeads were made by conjugating the extracted proteins to 0.8-microm carboxyl-coated polystyrene particles via carbodiimide coupling. BG Bugbeads were successfully detected by a bead-based enzyme-labeled immunoassay with fluorescence detection with a detection limit of 6.9 x 10(3) particles/mL. Formation of the Bugbead-capture bead complex was confirmed by ESEM. The concept of a harmless artificial spore can be applied to developing improved simulants for pathogenic spore-forming microorganisms such as B. anthracis, C. botulinum, and B. cereus, which can to be used for method validation, instrument calibration, and troubleshooting.

  13. Effect of Nanofibers on Spore Penetration and Lunar Dust Filtration

    Directory of Open Access Journals (Sweden)

    Phil Gibson, Ph.D.

    2008-06-01

    Full Text Available The results of two separate studies on biological spore penetration and simulated lunar dust filtration illustrate the use of nanofibers in some nonstandard filtration applications (nanofibers are generally defined as having diameters of less than a micron. In the first study, a variety of microporous liners containing microfibers and nanofibers were combined with cotton-based fabrics in order to filter aerosolized spores. The aerosol penetration resistance of the nanofiber-lined fabrics was measured, and some analysis was conducted of where the particles are captured within the fabric layers. Testing was conducted with aerosolized living spores, in order to evaluate the efficacy of various fabric treatments on spore viability within the fabric layers after exposure. Reported are the results of studies on fabrics with and without a removable electrospun nanofiber liner, and the fate of the spores within the fabric layers. In the second study, non-instrumented filtration testing using simulated lunar dust determined the comparative filtration efficiency of various nonwoven filtration media. Nanofiber witness media, combined with scanning electron microscope images, showed that an electrospun nonwoven filter layer effectively filtered out all the large and fine particles of the simulated lunar dust.

  14. Understanding of the importance of the spore coat structure and pigmentation in the Bacillus subtilis spore resistance to low-pressure plasma sterilization

    Science.gov (United States)

    Raguse, Marina; Fiebrandt, Marcel; Denis, Benjamin; Stapelmann, Katharina; Eichenberger, Patrick; Driks, Adam; Eaton, Peter; Awakowicz, Peter; Moeller, Ralf

    2016-07-01

    Low-pressure plasmas have been evaluated for their potential in biomedical and defense purposes. The sterilizing effect of plasma can be attributed to several active agents, including (V)UV radiation, charged particles, radical species, neutral and excited atoms and molecules, and the electric field. Spores of Bacillus subtilis were used as a bioindicator and a genetic model system to study the sporicidal effects of low-pressure plasma decontamination. Wild-type spores, spores lacking the major protective coat layers (inner, outer, and crust), pigmentation-deficient spores or spore impaired in encasement (a late step in coat assembly) were systematically tested for their resistance to low-pressure argon, hydrogen, and oxygen plasmas with and without admixtures. We demonstrate that low-pressure plasma discharges of argon and oxygen discharges cause significant physical damage to spore surface structures as visualized by atomic force microscopy. Spore resistance to low-pressure plasma was primarily dependent on the presence of the inner, and outer spore coat layers as well as spore encasement, with minor or less importance of the crust and spore pigmentation, whereas spore inactivation itself was strongly influenced by the gas composition and operational settings.

  15. Mechanism by which contact with plant cuticle triggers cutinase gene expression in the spores of Fusarium solani f. sp. pisi

    Energy Technology Data Exchange (ETDEWEB)

    Woloshuk, C.P.; Kolattukudy, P.E.

    1986-03-01

    Spores of the phytopathogenic fungus Fusarium solani f. sp. pisi were shown to produce the extracellular enzyme, cutinase, only when cutin or cutin hydrolysate was added to the spore suspension. Dihydroxy-C/sub 16/ acid and trihydroxy-C/sub 18/ acid, which are unique cutin monomers, showed the greatest cutinase-inducing activity. Experiments with several compounds structurally related to these fatty acids suggested that both a omega-hydroxyl and a midchain hydroxyl are required for cutinase-inducing activity. Cutinase appeared in the medium 30-45 min after the addition of the inducers to the spore suspension, and the activity level increased for 6 hr. Addition of cycloheximide (5 ..mu..g/ml) completely inhibited cutinase production, suggesting that protein synthesis was involved in the increase of cutinase activity. Immunoblot analysis with rabbit antibodies prepared against cutinase showed that cutinase protein increased in parallel with the increase in enzyme activity. Measurement of cutinase-specific RNA levels by dot-blot hybridization with /sup 32/P-labeled cutinase cDNA showed that the cutinase gene transcripts could be detected within 15 min after addition of the inducers. Addition of exogenous cutinase greatly enhanced the level of cutinase gene transcripts induced by cutin. These results strongly suggest that the fungal spore senses that it is in contact with the plant by the production of small amounts of cutin monomers catalyzed by the low level of cutinase carried by the spore and that these monomers induce the synthesis of cutinase needed for penetration of the fungus into the plant.

  16. Pollen and spores as a passive monitor of ultraviolet radiation

    Directory of Open Access Journals (Sweden)

    Wesley Toby Fraser

    2014-04-01

    Full Text Available Sporopollenin is the primary component of the outer walls of pollen and spores. The chemical composition of sporopollenin is responsive to levels of ultraviolet (UV radiation exposure, via a concomitant change in the concentration of phenolic compounds. This relationship offers the possibility of using fossil pollen and spore chemistry as a novel proxy for past UV flux. Phenolic compounds in sporopollenin can be quantified using Fourier Transform infrared spectroscopy. The high potential for preservation of pollen and spores in the geologic record, and the conservative nature of sporopollenin chemistry across the land plant phylogeny, means that this new proxy has the potential to reconstruct UV flux over much longer timescales than has previously been possible. This new tool has important implications for understanding the relationship between UV flux, solar insolation and climate in the past, as well as providing a possible means of assessing paleoaltitude, and ozone thickness.

  17. Role of dipicolinic acid in the germination, stability, and viability of spores of Bacillus subtilis.

    Science.gov (United States)

    Magge, Anil; Granger, Amanda C; Wahome, Paul G; Setlow, Barbara; Vepachedu, Venkata R; Loshon, Charles A; Peng, Lixin; Chen, De; Li, Yong-Qing; Setlow, Peter

    2008-07-01

    Spores of Bacillus subtilis spoVF strains that cannot synthesize dipicolinic acid (DPA) but take it up during sporulation were prepared in medium with various DPA concentrations, and the germination and viability of these spores as well as the DPA content in individual spores were measured. Levels of some other small molecules in DPA-less spores were also measured. These studies have allowed the following conclusions. (i) Spores with no DPA or low DPA levels that lack either the cortex-lytic enzyme (CLE) SleB or the receptors that respond to nutrient germinants could be isolated but were unstable and spontaneously initiated early steps in spore germination. (ii) Spores that lacked SleB and nutrient germinant receptors and also had low DPA levels were more stable. (iii) Spontaneous germination of spores with no DPA or low DPA levels was at least in part via activation of SleB. (iv) The other redundant CLE, CwlJ, was activated only by the release of high levels of DPA from spores. (v) Low levels of DPA were sufficient for the viability of spores that lacked most alpha/beta-type small, acid-soluble spore proteins. (vi) DPA levels accumulated in spores prepared in low-DPA-containing media varied greatly between individual spores, in contrast to the presence of more homogeneous DPA levels in individual spores made in media with high DPA concentrations. (vii) At least the great majority of spores of several spoVF strains that contained no DPA also lacked other major spore small molecules and had gone through some of the early reactions in spore germination.

  18. Flow-cytometric Analysis of Bacillus anthracis Spores

    Directory of Open Access Journals (Sweden)

    D. V. Kamboj

    2006-11-01

    Full Text Available Flow-cytometric technique has been established as a powerful tool for detection andidentification of microbiological agents. Unambiguous and rapid detection of Bacillus anthracisspores has been reported using immunoglobulin G-fluorescein isothiocyanate conjugate againstlive spores. In addition to the high sensitivity, the present technique could differentiate betweenspores of closely related species, eg, Bacillus cereus and Bacillus subtilis using fluorescenceintensity. The technique can be used for detection of live as well as inactivated spores makingit more congenial for screening of suspected samples of bioterrorism.

  19. Physical determinants of radiation sensitivity in bacterial spores

    Energy Technology Data Exchange (ETDEWEB)

    Powers, E.L.

    1982-01-01

    Several factors modifying radiation sensitivity in dry bacterial spores are described and discussed. Vacuum inducing the loss of critical structural water, very low dose rates of radiation from which the cell may recover, radiations of high linear energy transfer, and the action of temperature over long periods of time on previously irradiated cells are recognized from extensive laboratory work as important in determining survival of spores exposed to low radiation doses at low temperatures for long periods of time. Some extensions of laboratory work are proposed.

  20. Pulling the trigger: the mechanism of bacterial spore germination.

    Science.gov (United States)

    Foster, S J; Johnstone, K

    1990-01-01

    In spite of displaying the most extreme dormancy and resistance properties known among living systems, bacterial endospores retain an alert environment-sensing mechanism that can respond within seconds to the presence of specific germinants. This germination response is triggered in the absence of both germinant and germinant-stimulated metabolism. Genes coding for components of the sensing mechanism in spores of Bacillus subtilis have been cloned and sequenced. However, the molecular mechanism whereby these receptors interact with germinants to initiate the germination response is unknown. Recent evidence has suggested that in spores of Bacillus megaterium KM, proteolytic activation of an autolytic enzyme constitutes part of the germination trigger reaction.

  1. Inhibition of Bacillus cereus spore outgrowth and multiplication by chitosan.

    Science.gov (United States)

    Mellegård, Hilde; From, Cecilie; Christensen, Bjørn E; Granum, Per E

    2011-10-03

    Bacillus cereus is an endospore-forming bacterium able to cause food-associated illness. Different treatment processes are used in the food industry to reduce the number of spores and thereby the potential of foodborne disease. Chitosan is a polysaccharide with well-documented antibacterial activity towards vegetative cells. The activity against bacterial spores, spore germination and subsequent outgrowth and growth (the latter two events hereafter denoted (out)growth), however, is poorly documented. By using six different chitosans with defined macromolecular properties, we evaluated the effect of chitosan on Bacillus cereus spore germination and (out)growth using optical density assays and a dipicolinic acid release assay. (Out)growth was inhibited by chitosan, but germination was not. The action of chitosan was found to be concentration-dependent and also closely related to weight average molecular weight (M(w)) and fraction of acetylation (F(A)) of the biopolymer. Chitosans of low acetylation (F(A)=0.01 or 0.16) inhibited (out)growth more effectively than higher acetylated chitosans (F(A)=0.48). For the F(A)=0.16 chitosans with medium (56.8kDa) and higher M(w) (98.3kDa), a better (out)growth inhibition was observed compared to low M(w) (10.6kDa) chitosan. The same trend was not evident with chitosans of 0.48 acetylation, where the difference in activity between the low (19.6kDa) and high M(w) (163.0kDa) chitosans was only minor. In a spore test concentration corresponding to 10(2)-10(3)CFU/ml (spore numbers relevant to food), less chitosan was needed to suppress (out)growth compared to higher spore numbers (equivalent to 10(8)CFU/ml), as expected. No major differences in chitosan susceptibility between three different strains of B. cereus were detected. Our results contribute to a better understanding of chitosan activity towards bacterial spore germination and (out)growth.

  2. Bacillus cereus spores and cereulide in food-borne illness

    OpenAIRE

    Shaheen, Ranad

    2009-01-01

    B. cereus is a gram-positive bacterium that possesses two different forms of life:the large, rod-shaped cells (ca. 0.002 mm by 0.004 mm) that are able to propagate and the small (0.001 mm), oval shaped spores. The spores can survive in almost any environment for up to centuries without nourishment or water. They are insensitive towards most agents that normally kill bacteria: heating up to several hours at 90 ºC, radiation, disinfectants and extreme alkaline (≥ pH 13) and acid (≀ pH 1) e...

  3. Effect of synthetic detergents on germination of fern spores

    Energy Technology Data Exchange (ETDEWEB)

    Devi, Y.; Devi, S.

    1986-12-01

    Synthetic detergents constitute one of the most important water pollutants by contaminating the lakes and rivers through domestic and industrial use. Considerable information is now available for the adverse effects of detergents an aquatic fauna including fish, algae, and higher aquatic plants. Marked inhibition of germination in orchids and brinjals and of seedlings growth in raddish suggest that rapidly growing systems could be sensitive to detergent polluted water. The present study of the effect of linear alkyl benzene sulphonate on germination of the spores of a fern, Diplazium esculentum aims at the understanding of the effects of water pollution on pteridophytes and the development of spore germination assay for phytoxicity evaluation.

  4. Characteristics of spore germination and protonemal development in Hypnum pacleseens

    Institute of Scientific and Technical Information of China (English)

    HUANG Shiliang; LI Min; ZHAO Jiancheng; ZHANG Yuanming; WANG Zhenjie

    2006-01-01

    The spore germination,protonemal development,and gametophyte differentiation of Hypnum pacleseens were observed in cultivation.Photomicrographs showed that spore germination of Hypnum pacleseens occured within the exospore.Its protonema is massive with filamentous chloronema formed inside.The terminal part of the chloronema differentiated into filamentous caulonema and its rhizoid was derived from the apical cell of the filamentous chloronema.The initial cell of gametophyte differentiated from chloronema and caulonema.Sporeling type of Hypnum pacleseens is developmentally similar to Glyphmitrium-type.

  5. Systematic Assessment of Nonproteolytic Clostridium botulinum Spores for Heat Resistance

    Science.gov (United States)

    Stringer, Sandra C.; Barker, Gary C.; Peck, Michael W.

    2016-01-01

    ABSTRACT Heat treatment is an important controlling factor that, in combination with other hurdles (e.g., pH, aw), is used to reduce numbers and prevent the growth of and associated neurotoxin formation by nonproteolytic C. botulinum in chilled foods. It is generally agreed that a heating process that reduces the spore concentration by a factor of 106 is an acceptable barrier in relation to this hazard. The purposes of the present study were to review the available data relating to heat resistance properties of nonproteolytic C. botulinum spores and to obtain an appropriate representation of parameter values suitable for use in quantitative microbial risk assessment. In total, 753 D values and 436 z values were extracted from the literature and reveal significant differences in spore heat resistance properties, particularly those corresponding to recovery in the presence or absence of lysozyme. A total of 503 D and 338 z values collected for heating temperatures at or below 83°C were used to obtain a probability distribution representing variability in spore heat resistance for strains recovered in media that did not contain lysozyme. IMPORTANCE In total, 753 D values and 436 z values extracted from literature sources reveal significant differences in spore heat resistance properties. On the basis of collected data, two z values have been identified, z = 7°C and z = 9°C, for spores recovered without and with lysozyme, respectively. The findings support the use of heat treatment at 90°C for 10 min to reduce the spore concentration by a factor of 106, providing that lysozyme is not present during recovery. This study indicates that greater heat treatment is required for food products containing lysozyme, and this might require consideration of alternative recommendation/guidance. In addition, the data set has been used to test hypotheses regarding the dependence of spore heat resistance on the toxin type and strain, on the heating technique used, and on the

  6. Discrimination of Spore-Forming Bacilli Using spoIVA

    Science.gov (United States)

    Venkateswaran, Kasthuri; LaDuc, Myron; Stuecker, Tara

    2009-01-01

    A method of discriminating between spore-forming and non-spore-forming bacteria is based on a combination of simultaneous sporulation-specific and non-sporulation-specific quantitative polymerase chain reactions (Q-PCRs). The method was invented partly in response to the observation that for the purposes of preventing or reducing biological contamination affecting many human endeavors, ultimately, only the spore-forming portions of bacterial populations are the ones that are problematic (or, at least, more problematic than are the non-spore-forming portions). In some environments, spore-forming bacteria constitute small fractions of the total bacterial populations. The use of sporulation-specific primers in Q-PCR affords the ability to assess the spore-forming fraction of a bacterial population present in an environment of interest. This assessment can provide a more thorough and accurate understanding of the bacterial contamination in the environment, thereby making it possible to focus contamination- testing, contamination-prevention, sterilization, and decontamination resources more economically and efficiently. The method includes the use of sporulation-specific primers in the form of designed, optimized deoxyribonucleic acid (DNA) oligonucleotides specific for the bacterial spoIVA gene (see table). [In "spoIVA," "IV" signifies Roman numeral four and the entire quoted name refers to gene A for the fourth stage of sporulation.] These primers are mixed into a PCR cocktail with a given sample of bacterial cells. A control PCR cocktail into which are mixed universal 16S rRNA primers is also prepared. ["16S rRNA" denotes a ribosomal ribonucleic acid (rRNA) sequence that is common to all organisms.] Following several cycles of heating and cooling according to the PCR protocol to amplify amounts of DNA molecules, the amplification products can be analyzed to determine the types of bacterial cells present within the samples. If the amplification product is strong

  7. FORMALDEHYDE GAS INACTIVATION OF BACILLUS ANTHRACIS, BACILLUS SUBTILIS AND GEOBACILLUS STEAROTHERMOPHILUS SPORES ON INDOOR SURFACE MATERIALS.

    Science.gov (United States)

    Research evaluated the decontamination of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surface material using formaldehyde gas. Spores were dried on seven types of indoor surfaces and exposed to 1100 ppm formaldehyde gas for 10 hr. Fo...

  8. A novel, inducible, citral lyase purified from spores of Penicillium digitatum

    NARCIS (Netherlands)

    Wolken, W.A.M.; Loo, W.J.V. van; Tramper, J.; Werf, M.J. van der

    2002-01-01

    A novel lyase, combining hydratase and aldolase activity, that converts citral into methylheptenone and acetaldehyde, was purified from spores of Penicillium digitatum. Remarkably, citral lyase activity was induced 118-fold by incubating nongerminating spores with the substrate, citral. This cofacto

  9. Inside the Meteorite — Bacterial Spore Survival After Exposure to Galactic Cosmic Radiation

    Science.gov (United States)

    Moeller, R.; Berger, T.; Matthiä, D.; Okayasu, R.; Kato, T.; Kitamura, H.; Reitz, G.

    2010-04-01

    Based on their unique resistance to various space parameters, bacterial spores are one of the model systems used for astrobiological studies. In our research, we studied the response of Bacillus subtilis spores to the exposure of galactic cosmic radiation.

  10. Surface Hydrophobicity and Surface Rigidity Induce Spore Germination in Colletotrichum graminicola.

    Science.gov (United States)

    Chaky, J; Anderson, K; Moss, M; Vaillancourt, L

    2001-06-01

    ABSTRACT We investigated the relationship between physical characteristics of artificial surfaces, spore attachment, and spore germination in Colletotrichum graminicola. Surface hydrophobicity and surface rigidity were both signals for breaking dormancy and initiating spore germination, but spore attachment alone was not an important inducing signal. The presence of a carbon source overrode the necessity for a rigid, hydrophobic substrate for spore germination. Spore attachment was typically stronger to more hydrophobic surfaces, but certain hydrophilic surfaces also proved to be good substrates for spore attachment. In contrast to spore germination, appressorial induction was more dependent on attachment to a rigid substrate than it was on surface hydrophobicity. Appressoria were induced efficiently on hydrophilic surfaces, as long as there was significant conidial attachment to those surfaces.

  11. A novel, inducible, citral lyase purified from spores of Penicillium digitatum

    NARCIS (Netherlands)

    Wolken, W.A.M.; Loo, W.J.V. van; Tramper, J.; Werf, M.J. van der

    2002-01-01

    A novel lyase, combining hydratase and aldolase activity, that converts citral into methylheptenone and acetaldehyde, was purified from spores of Penicillium digitatum. Remarkably, citral lyase activity was induced 118-fold by incubating nongerminating spores with the substrate, citral. This

  12. Surface charge and hydrodynamic coefficient measurements of Bacillus subtilis spore by optical tweezers.

    Science.gov (United States)

    Pesce, Giuseppe; Rusciano, Giulia; Sasso, Antonio; Isticato, Rachele; Sirec, Teja; Ricca, Ezio

    2014-04-01

    In this work we report on the simultaneous measurement of the hydrodynamic coefficient and the electric charge of single Bacillus subtilis spores. The latter has great importance in protein binding to spores and in the adhesion of spores onto surfaces. The charge and the hydrodynamic coefficient were measured by an accurate procedure based on the analysis of the motion of single spores confined by an optical trap. The technique has been validated using charged spherical polystyrene beads. The excellent agreement of our results with the expected values demonstrates the quality of our procedure. We measured the charge of spores of B. subtilis purified from a wild type strain and from two isogenic mutants characterized by an altered spore surface. Our technique is able to discriminate the three spore types used, by their charge and by their hydrodynamic coefficient which is related to the hydrophobic properties of the spore surface. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Palynological investigation of the sediment cores from the Arabian Sea 1 Fungal spores

    Digital Repository Service at National Institute of Oceanography (India)

    Chandra, A.; Saxena, R.K.; Setty, M.G.A.P.

    The paper deals with the systematic study of the fungal spores recovered from five sediment cores from the Arabian Sea The fungal spore assemblage recorded here includes 12 genera viz., @iInapertisporites, Dicellaesporites, Multicellaesporites...

  14. The combined effect of high pressure and nisin or lysozyme on the inactivation of Alicyclobacillus acidoterrestris spores in apple juice

    Science.gov (United States)

    Sokołowska, B.; Skąpska, S.; Fonberg-Broczek, M.; Niezgoda, J.; Chotkiewicz, M.; Dekowska, A.; Rzoska, S.

    2012-03-01

    Alicyclobacillus acidoterrestris, a thermoacidophilic and spore-forming bacterium is one of the important target micro-organisms in the quality control of acidic canned foods. High pressure pasteurization (HPP) at 50°C was used for the inactivation of A. acidoterrestris spores in apple juice. Pressure applied both in a continuous and oscillatory mode gave the best results when 200 MPa was used. Increasing the pressure to 500 MPa, as well as lowering its value to 100 MPa, had an adverse effect on the effectiveness of the process. The best results were achieved with the use of a combined treatment, involving oscillatory pressurization at 200 MPa, followed by holding the sample for 60 min at atmospheric pressure and subsequent pressurization at 500 MPa, resulting in a reduction in the spore count of 6.15 log. Nisin significantly enhanced the effect of HPP at 300 MPa. Using pressure of 200 MPa for 45 min with a nisin concentration of 250 IU/mL enabled total spore inactivation (over 6 log). No significant effect of lysozyme at a concentration of 0.05 and 0.1 mg/L at 300 MPa was observed.

  15. A laboratory assessment of the Waveband Integrated Bioaerosol Sensor (WIBS-4) using individual samples of pollen and fungal spore material

    Science.gov (United States)

    Healy, David A.; O'Connor, David J.; Burke, Aoife M.; Sodeau, John R.

    2012-12-01

    A Bioaerosol sensing instrument referred to as WIBS-4, designed to continuously monitor ambient bioaerosols on-line, has been used to record a multiparameter “signature” from each of a number of Primary Biological Aerosol Particulate (PBAP) samples found in air. These signatures were obtained in a controlled laboratory environment and are based on the size, asymmetry (“shape”) and auto-fluorescence of the particles. Fifteen samples from two separate taxonomic ranks (kingdoms), Plantae (×8) and Fungi (×7) were individually introduced to the WIBS-4 for measurement along with two non-fluorescing chemical solids, common salt and chalk. Over 2000 individual-particle measurements were recorded for each sample type and the ability of the WIBS spectroscopic technique to distinguish between chemicals, pollen and fungal spore material was examined by identifying individual PBAP signatures. The results obtained show that WIBS-4 could potentially be a very useful analytical tool for distinguishing between natural airborne PBAP samples, such as the fungal spores and may potentially play an important role in detecting and discriminating the toxic fungal spore, Aspergillus fumigatus, from others in real-time. If the sizing range of the commercial instrument was customarily increased and permitted to operate simultaneously in its two sizing ranges, pollen and spores could potentially be discriminated between. The data also suggest that the gain setting sensitivity on the detector would also have to be reduced by a factor >5, to routinely detect, in-range fluorescence measurements for pollen samples.

  16. Influence of Ganoderma lucidum spores on the levels of neuropeptide Y and somatostatin in brains of seizure rats

    Institute of Scientific and Technical Information of China (English)

    Kongli Zhu; Ming Lu; Shuqiu Wang; Shiling Zhang; Dixiang Sun

    2008-01-01

    BACKGROUND: Previous research has revealed that somatostatin can induce epilepsy, and that the levels of neuropeptide Y may increase and become more active in brain areas with epileptic seizures.OBJECTIVE: To observe the effect of Ganoderma lucidum spore powder on the neuropeptide Y and somatostatin content in the cerebral cortex and hippocampal regions of seizure rats induced by pentylenetetrazol (PTZ). Furthermore, to verify any effect of Ganoderma lucidum spore powder on inhibition of epileptic seizures.DESIGN, TIME AND SETTING: A randomized group animal study was performed in August 2007 in the School of Basic Medical Sciences, Jiamusi University (Jiamusi, Heilongjiang, China).MATERIALS: Thirty healthy, male, Wistar rats, aged 12 weeks and weighing 180-220g, were taken as the experimental animals. PTZ (Sigma Company, United States) was used to induce epilepsy. Ganoderma lucidum spores (Leyss, ex Fr variety) were purchased from Jiamusi City Wild Growing Case of the Ganoderma Lucidum (China). Rabbit anti-somatostatin antibodies and secondary antibodies were purchased from Wuhan Boster Company (China). Neuropeptide Y radioimmunoassay kit was purchased from Beijing Furui Biotechnology Company (China).METHODS: Thirty rats were randomly divided into three groups: a control group, an epilepsy model group and a Ganoderma lucidum spore-treated group. Each group contained 10 animals. Rats in the epilepsy model group were treated with intraperitoneal injections of PTZ and gastric perfusion of physiologic saline, In the Ganoderma lucidum spore-treated group, intraperitoneal injection of PTZ and gastric perfusion of Ganoderma lucidum spore powder were administered. The blank control group was only administered with the physiological saline by intraperitoneal injection and gastric perfusion.MAIN OUTCOME MEASURES: Immunohistochemical staining and radioimmunoassay methods were used to observe the changes of somatostatin and neuropeptide Y content in brain tissue of epileptic

  17. Impact of Spore Biology on the Rate of Kill and Suppression of Resistance in Bacillus anthracis▿

    OpenAIRE

    Drusano, G L; Okusanya, O. O.; Okusanya, A. O.; van Scoy, B.; Brown, D L; Fregeau, C.; Kulawy, R.; Kinzig, M; Sörgel, F; Heine, H. S.; Louie, A

    2009-01-01

    Bacillus anthracis is complex because of its spore form. The spore is invulnerable to antibiotic action. It also has an impact on the emergence of resistance. We employed the hollow-fiber infection model to study the impacts of different doses and schedules of moxifloxacin on the total-organism population, the spore population, and the subpopulations of vegetative- and spore-phase organisms that were resistant to moxifloxacin. We then generated a mathematical model of the impact of moxifloxac...

  18. Observations on the migration of bacillus spores outside a contaminated facility during a decontamination efficacy study

    Science.gov (United States)

    Silvestri, Erin E.; Perkins, Sarah; Lordo, Robert; Kovacik, William; Nichols, Tonya L.; Bowling, Charlena Yoder; Griffin, Dale W.; Schaefer, Frank W.

    2015-01-01

    The potential for an intentional wide-area or indoor release of Bacillus anthracis spores remains a concern, but the fate and transport of B. anthracis spores in indoor and outdoor environments are not well understood. Some studies have examined the possibility of spore transport within ventilation systems and in buildings and transport into a building following an outdoor release. Little research exists regarding the potential for spores to migrate to the outside of a building following an indoor release.

  19. Characterization of fungal spores in ambient particulate matter: A study from the Himalayan region

    Science.gov (United States)

    Kumar, Ajay; Attri, Arun K.

    2016-10-01

    Fungal spores as a constituent of ambient particulate matter (PM) is of concern; they not only display the physical traits of a particle, but are also potential allergens and health risk. An investigation over fourteen month was undertaken at a rural site located in the Western Himalayan region, to evaluate the PM associated fungal spores' concentration and diversity. The season-wise change in the fungal spores concentration in the Coarse Particulate Matter (CPM) fraction (aerodynamic diameter > 10 μm) varied from 500 to 3899 spores m-3. Their average concentration over 14 months was 1517 spores m-3. Significant diversity of fungal spores in the CPM samples was observed; 27 individual genera of fungal spores were identified, of which many were known allergens. Presence of Ascomycota and Basidiomycota fungal spores was dominant in the samples; ∼20% of the spores were un-characterized. The season-wise variability in fungal spores showed a statistically significant high correlation with CPM load. Maximum number concentration of the spores in CPM was recorded in the summer, while minimum in the winter. The high diversity of spores occurred during monsoon and post monsoon months. The meteorological factors played an important role in the fungal spores' distribution profile. The temporal profile of the spores showed significant correlation with the ambient temperature (T), relative humidity (RH), wind speed (WS) and planetary boundary layer (PBL) height. Strong correlation of WS with fungal spores and CPM, and wind back trajectories suggest that re-suspension and wind assisted transport of PM contributes to ambient CPM associated fungal spores.

  20. Gene activity during germination of spores of the fern, Onoclea sensibilis. Cell-free translation analysis of mRNA of spores and the effect of alpha-amanitin on spore germination

    Science.gov (United States)

    Raghavan, V.

    1992-01-01

    Poly(A)-RNA fractions of dormant, dark-imbibed (non-germinating) and photoinduced (germinating) spores of Onoclea sensibilis were poor templates in the rabbit reticulocyte lysate protein synthesizing system, but the translational efficiency of poly(A)+RNA was considerably higher than that of unfractionated RNA. Poly(A)+RNA isolated from photoinduced spores had a consistently higher translational efficiency than poly(A)+RNA from dark-imbibed spores. Analysis of the translation products by one-dimensional polyacrylamide gel electrophoresis showed no qualitative differences in the mRNA populations of dormant, dark-imbibed, and photoinduced spores. However, poly(A)+RNA from dark-imbibed spores appeared to encode in vitro fewer detectable polypeptides at a reduced intensity than photoinduced spores. A DNA clone encoding the large subunit of maize ribulose bisphosphate carboxylase hybridized at strong to moderate intensity to RNA isolated from dark-imbibed spores, indicating the absence of mRNA degradation. Although alpha-amanitin did not inhibit the germination of spores, the drug prevented the elongation of the rhizoid and protonemal initial with a concomitant effect on the synthesis of poly(A)+RNA. These results are consistent with the view that some form of translational control involving stored mRNA operates during dark-imbibition and photoinduced germination of spores.

  1. Effect of concentration, exposure time, temperature, and relative humidity on the toxicity of sulfur dioxide to the spores of Botrytis cinerea

    Energy Technology Data Exchange (ETDEWEB)

    Couey, H.M.; Uota, M.

    1961-12-01

    When spores of Botrytis cinerea are exposed to SO/sub 2/ gas, the subsequent reduction in spore germination is quantitatively proportional to the SO/sub 2/ concentration and the exposure time. The toxicity of SO/sub 2/ increases with increasing relative humidity. In an atmosphere of 96% RH, SO/sub 2/ is more than 20 times as effective as at 75% RH. The toxicity also increases about 1.5 times for each 10/sup 0/C rise in temperature between 0/sup 0/ and 30/sup 0/C. 8 references, 4 figures, 1 table.

  2. Impact of sorbic acid on germination and outgrowth heterogeneity of Bacillus cereus ATCC 14579 spores

    NARCIS (Netherlands)

    Besten, den H.M.W.; Melis, van C.C.J.; Sanders, J.W.; Nierop Groot, M.N.; Abee, T.

    2012-01-01

    Population heterogeneity complicates the predictability of the outgrowth kinetics of individual spores. Flow cytometry sorting and monitoring of the germination and outgrowth of single dormant spores allowed the quantification of acid-induced spore population heterogeneity at pH 5.5 and in the prese

  3. Influence of food matrix on outgrowth heterogeneity of heat damaged Bacillus cereus spores

    NARCIS (Netherlands)

    Warda, A.K.; Besten, den H.M.W.; Sha, N.; Abee, T.; Nierop Groot, M.N.

    2015-01-01

    Spoilage of heat treated foods can be caused by the presence of surviving spore-formers. It is virtually impossible to prevent contamination at the primary production level as spores are ubiquitous present in the environment and can contaminate raw products. As a result spore inactivation treatments

  4. Influence of food matrix on outgrowth heterogeneity of heat damaged Bacillus cereus spores

    NARCIS (Netherlands)

    Warda, A.K.; Besten, den H.M.W.; Sha, N.; Abee, T.; Nierop Groot, M.N.

    2015-01-01

    Spoilage of heat treated foods can be caused by the presence of surviving spore-formers. It is virtually impossible to prevent contamination at the primary production level as spores are ubiquitous present in the environment and can contaminate raw products. As a result spore inactivation treatments

  5. Concentrations of butyric acid bacteria spores in silage and relationships with aerobic deterioration

    NARCIS (Netherlands)

    Vissers, M.M.M.; Driehuis, F.; Giffel, M.C.T.; Jong, de P.; Lankveld, J.M.G.

    2007-01-01

    Germination and growth of spores of butyric acid bacteria ( BAB) may cause severe defects in semihard cheeses. Silage is the main source of BAB spores in cheese milk. The objectives of the study were to determine the significance of grass silages and corn silages as sources of BAB spores and to inve

  6. SporeWeb : an interactive journey through the complete sporulation cycle of Bacillus subtilis

    NARCIS (Netherlands)

    Eijlander, Robyn T.; Jong, Anne de; Krawczyk, Antonina O.; Holsappel, Siger; Kuipers, Oscar P.

    2014-01-01

    Bacterial spores are a continuous problem for both food-based and health-related industries. Decades of scientific research dedicated towards understanding molecular and gene regulatory aspects of sporulation, spore germination and spore properties have resulted in a wealth of data and information.

  7. Effect of temperature on green spore longevity for the ferns Equisetum ramosissimum and Osmunda regalis

    Science.gov (United States)

    Some fern species produce chlorophyllic or green spores. Green spores lose viability quickly compared to nongreen spores, and so need specialized treatment for long term conservation in germplasm banks. Dry storage at different temperatures (25 ºC, 4 ºC, -25 ºC, -80 ºC and -196 ºC) was studied in ...

  8. Spore-killing meiotic drive factors in a natural population of the fungus Podospora anserina

    NARCIS (Netherlands)

    Gaag, van der M.; Debets, A.J.M.; Oosterhof, J.; Slakhorst, S.M.; Thijssen, J.A.G.M.; Hoekstra, R.F.

    2000-01-01

    In fungi, meiotic drive is observed as spore killing. In the secondarily homothallic ascomycete Podospora anserina it is characterized by the abortion of two of the four spores in the ascus. We have identified seven different types of meiotic drive elements (Spore killers). Among 99 isolates from na

  9. Modeling Radiation Effectiveness for Inactivation of Bacillus Spores

    Science.gov (United States)

    2015-09-17

    EFFECTIVENESS FOR INACTIVATION OF BACILLUS SPORES Emily A. Knight, B.A., M.S. Major, USAF Committee Membership: Dr. William P. Baker Chair Dr. Larry W...linked to food poisoning and causes gastrointestinal diseases with symptoms ranging from mild nausea to frequent vomiting . However, as described above

  10. 14C Analysis of protein extracts from Bacillus spores.

    Science.gov (United States)

    Cappuccio, Jenny A; Falso, Miranda J Sarachine; Kashgarian, Michaele; Buchholz, Bruce A

    2014-07-01

    Investigators of bioagent incidents or interdicted materials need validated, independent analytical methods that will allow them to distinguish between recently made bioagent samples versus material drawn from the archives of a historical program. Heterotrophic bacteria convert the carbon in their food sources, growth substrate or culture media, into the biomolecules they need. The F(14)C (fraction modern radiocarbon) of a variety of media, Bacillus spores, and separated proteins from Bacillus spores was measured by accelerator mass spectrometry (AMS). AMS precisely measures F(14)C values of biological materials and has been used to date the synthesis of biomaterials over the bomb pulse era (1955 to present). The F(14)C of Bacillus spores reflects the radiocarbon content of the media in which they were grown. In a survey of commercial media we found that the F(14)C value indicated that carbon sources for the media were alive within about a year of the date of manufacture and generally of terrestrial origin. Hence, bacteria and their products can be dated using their (14)C signature. Bacillus spore samples were generated onsite with defined media and carbon free purification and also obtained from archived material. Using mechanical lysis and a variety of washes with carbon free acids and bases, contaminant carbon was removed from soluble proteins to enable accurate (14)C bomb-pulse dating. Since media is contemporary, (14)C bomb-pulse dating of isolated soluble proteins can be used to distinguish between historical archives of bioagents and those produced from recent media.

  11. Pollen and spores as a passive monitor of ultraviolet radiation

    NARCIS (Netherlands)

    Fraser, W.T.; Lomax, B.H.; Jardine, P.E.; Gosling, W.D.; Sephton, M.A.

    2014-01-01

    Sporopollenin is the primary component of the outer walls of pollen and spores. The chemical composition of sporopollenin is responsive to levels of ultraviolet (UV) radiation exposure, via a concomitant change in the concentration of phenolic compounds. This relationship offers the possibility of

  12. Phylogenetic placement of two species known only from resting spores

    DEFF Research Database (Denmark)

    Hajek, Ann E; Gryganskyi, Andrii; Bittner, Tonya;

    2016-01-01

    Molecular methods were used to determine the generic placement of two species of Entomophthorales known only from resting spores. Historically, these species would belong in the form-genus Tarichium, but this classification provides no information about phylogenetic relationships. Using DNA from...

  13. Multigeneration Cross-Contamination of Mail with Bacillus anthracis Spores.

    Directory of Open Access Journals (Sweden)

    Jason Edmonds

    Full Text Available The release of biological agents, including those which could be used in biowarfare or bioterrorism in large urban areas, has been a concern for governments for nearly three decades. Previous incidents from Sverdlosk and the postal anthrax attack of 2001 have raised questions on the mechanism of spread of Bacillus anthracis spores as an aerosol or contaminant. Prior studies have demonstrated that Bacillus atrophaeus is easily transferred through simulated mail handing, but no reports have demonstrated this ability with Bacillus anthracis spores, which have morphological differences that may affect adhesion properties between spore and formite. In this study, equipment developed to simulate interactions across three generations of envelopes subjected to tumbling and mixing was used to evaluate the potential for cross-contamination of B. anthracis spores in simulated mail handling. In these experiments, we found that the potential for cross-contamination through letter tumbling from one generation to the next varied between generations while the presence of a fluidizer had no statistical impact on the transfer of material. Likewise, the presence or absence of a fluidizer had no statistically significant impact on cross-contamination levels or reaerosolization from letter opening.

  14. The proteome of spore surface layers in food spoiling bacteria

    NARCIS (Netherlands)

    Abhyankar, W.R.

    2014-01-01

    Endospores are dormant, multilayered, highly resistant cellular structures formed in response to stress by certain bacteria belonging to the genera Bacillus, Clostridium and other related organisms. In presence of nutrients and favorable conditions spores germinate and grow out as normal vegetative

  15. Refined multivalent display of bacterial spore-binding peptides.

    Science.gov (United States)

    Lusvarghi, Sabrina; Kim, Jenny Morana; Creeger, Yehuda; Armitage, Bruce Alan

    2009-05-07

    A multiple antigen peptide display scaffold was used to create multivalent versions of a heptapeptide selected previously by phage display to bind to Bacillus subtilis spores. A simple flow cytometric assay was developed in which a biotinylated form of the peptide was first bound to fluorescent streptavidin, then the fluorescent streptavidin-peptide complex was bound to spores before introduction into the cytometer. This assay clearly demonstrated that the tetravalent scaffold enhanced the affinity for B. subtilis spores by greater than 1 and 2 orders of magnitude when compared to divalent and monovalent analogues, respectively. However, variations in the number and flexibility of spacer residues within the scaffold did not significantly affect the binding affinity of the tetravalent peptides. Similar to prior reports, these multivalent scaffolds are effective most likely because they mimic the multivalent display of the original peptide library on the phage coat. Moreover, the tetravalent peptides can be readily integrated into a variety of heterogeneous and homogeneous spore-detection assay formats.

  16. Phospholipase C delta regulates germination of Dictyostelium spores

    NARCIS (Netherlands)

    Van Dijken, P.; Van Haastert, PJM

    2001-01-01

    Background: Many eukaryotes including plants and fungi make spores that resist severe environmental stress. The micro-organism Dictyostelium contains a single phospholipase C gene (PLC); deletion of the gene has no effect on growth cell movement and differentiation. In this report we show that PLC

  17. Phospholipase C delta regulates germination of Dictyostelium spores

    NARCIS (Netherlands)

    Van Dijken, P.; Van Haastert, PJM

    2001-01-01

    Background: Many eukaryotes including plants and fungi make spores that resist severe environmental stress. The micro-organism Dictyostelium contains a single phospholipase C gene (PLC); deletion of the gene has no effect on growth cell movement and differentiation. In this report we show that PLC i

  18. Stem rust spores elicit rapid RPG1 phosphorylation

    Science.gov (United States)

    Stem rust threatens cereal production worldwide. Understanding the mechanism by which durable resistance genes, such as Rpg1, function is critical. We show that the RPG1 protein is phosphorylated within 5 min by exposure to spores from avirulent but not virulent races of stem rust. Transgenic mutant...

  19. Multigeneration Cross-Contamination of Mail with Bacillus anthracis Spores

    Science.gov (United States)

    Edmonds, Jason; Lindquist, H. D. Alan; Sabol, Jonathan; Martinez, Kenneth; Shadomy, Sean; Cymet, Tyler; Emanuel, Peter

    2016-01-01

    The release of biological agents, including those which could be used in biowarfare or bioterrorism in large urban areas, has been a concern for governments for nearly three decades. Previous incidents from Sverdlosk and the postal anthrax attack of 2001 have raised questions on the mechanism of spread of Bacillus anthracis spores as an aerosol or contaminant. Prior studies have demonstrated that Bacillus atrophaeus is easily transferred through simulated mail handing, but no reports have demonstrated this ability with Bacillus anthracis spores, which have morphological differences that may affect adhesion properties between spore and formite. In this study, equipment developed to simulate interactions across three generations of envelopes subjected to tumbling and mixing was used to evaluate the potential for cross-contamination of B. anthracis spores in simulated mail handling. In these experiments, we found that the potential for cross-contamination through letter tumbling from one generation to the next varied between generations while the presence of a fluidizer had no statistical impact on the transfer of material. Likewise, the presence or absence of a fluidizer had no statistically significant impact on cross-contamination levels or reaerosolization from letter opening. PMID:27123934

  20. Ascoaphaera osmophila sp.nov. An Australian Spore Cyst

    DEFF Research Database (Denmark)

    Skou, Jens-Peder; King, , J.

    1984-01-01

    Ascosphaera osmophila sp. nov. is described. Septa occur often close together and remain intact when the mycelium disintegrates. A fairly good production of mature spore cysts occurs only on media containing 10% sugar or more. A. osmophila lives in association with the mason bee, Chalicodoma...

  1. Spore to spore culture of Didymium operculatum, a new Myxomycete from the Atacama Desert of Chile.

    Science.gov (United States)

    de Basanta, D Wrigley; Lado, C; Estrada-Torres, A

    2011-01-01

    A new species of Didymium (Myxomycetes), D. operculatum, is described in this paper, and details of its life cycle are provided. The new species was recorded during studies of the Atacama Desert in Chile. It has been collected directly in the field and isolated in moist chamber cultures prepared with material from an endemic cactus. The distinguishing characters of this species are its dehiscence by means of an apical operculum combined with a whitish calcareous stalk and the banded reticulate ornamentation of the spores. The morphology of this new myxomycete was examined with scanning electron microscopy and light microscopy, and micrographs of relevant details are included in this paper. Some comments are made on the patterns of distribution of Didymium species in arid lands and adaptive characters enabling this genus to colonize such extreme environments. It is proposed that a longer cycle and the ability to resort to resistant forms many times during their development reflect the response of these myxomycetes to the largely unfavorable conditions of their environment.

  2. Radiosensitivity of spores of Paenibacillus larvae ssp. larvae in honey

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Wanderley Mendes de [Ministerio da Agricultura, Pecuaria e Abastecimento, Rio de Janeiro, RJ (Brazil). Servico de Inspecao de Produtos de Origem Animal]. E-mail: sipa-rj@agricultura.gov.br; Vital, Helio de Carvalho [Centro Tecnologico do Exercito CTEx, Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear]. E-mail: vital@ctex.eb.br; Schuch, Dulce Maria Tocchetto [Ministerio da Agricultura, Pecuaria e Abastecimento, Porto Alegre, RS (Brazil)]. E-mail: micro-lara-rs@agricultura.gov.br

    2007-07-01

    Irradiation, usually used in combination with other conventional methods of conservation, has been proven to be an efficient tool to ensure the safety of many types of foods by destroying pathogenic microorganisms and extending their shelf-lives. This work has investigated the efficacy of gamma irradiation to inactivate spores of the bacterium Paenibacillus larvae that causes the 'American foulbrood', a highly contagious disease still exotic in Brazil that kills bees and contaminates honey, preventing its commercialization and causing great economical losses. In this study, 60 g samples of two types of honey inoculated with 3.5x10{sup 3} spores/mL of that bacterium were irradiated with doses of 0, 5, 7.5, 10, 12.5 and 15 kGy and counted. The analyses indicated a mean reduction of 97.5{+-}0.7% in the number of viable spores exposed to 5 kGy. The application of doses of 7.5 kGy or higher yielded no viable spores above the detection threshold (10/mL). In addition the value of D{sub 10} (3.1{+-}0.3 kGy) was estimated and the logarithm of the population of viable spores of Paenibacillus larvae subsp. larvae was determined as linear and quadratic polynomial functions of the radiation dose. The results indicated that the dose of 10 kGy could be insufficient to assure complete sterilization of honey in some cases while suggesting that 25 kGy would perform such task adequately. (author)

  3. Fighting Ebola through Novel Spore Decontamination Technologies for the Military

    Directory of Open Access Journals (Sweden)

    Christopher J. Doona

    2015-08-01

    Full Text Available AbstractRecently, global public health organizations such as Doctors without Borders (MSF, the World Health Organization (WHO, Public Health Canada, National Institutes of Health (NIH, and the U.S. government developed and deployed Field Decontamination Kits (FDKs, a novel, lightweight, compact, reusable decontamination technology to sterilize Ebola-contaminated medical devices at remote clinical sites lacking infra-structure in crisis-stricken regions of West Africa (medical waste materials are placed in bags and burned. The basis for effectuating sterilization with FDKs is chlorine dioxide (ClO2 produced from a patented invention developed by researchers at the US Army – Natick Soldier RD&E Center (NSRDEC and commercialized as a dry mixed-chemical for bacterial spore decontamination. In fact, the NSRDEC research scientists developed an ensemble of ClO2 technologies designed for different applications in decontaminating fresh produce; food contact and handling surfaces; personal protective equipment; textiles used in clothing, uniforms, tents, and shelters; graywater recycling; airplanes; surgical instruments; and hard surfaces in latrines, laundries, and deployable medical facilities. These examples demonstrate the far-reaching impact, adaptability, and versatility of these innovative technologies. We present herein the unique attributes of NSRDEC’s novel decontamination technologies and a Case Study of the development of FDKs that were deployed in West Africa by international public health organizations to sterilize Ebola-contaminated medical equipment. FDKs use bacterial spores as indicators of sterility. We review the properties and structures of spores and the mechanisms of bacterial spore inactivation by ClO2. We also review mechanisms of bacterial spore inactivation by novel, emerging, and established nonthermal technologies for food preservation, such as high pressure processing, irradiation, cold plasma, and chemical sanitizers

  4. Dynamics of Bacillus thuringiensis var. israelensis and Lysinibacillus sphaericus spores in urban catch basins after simultaneous application against mosquito larvae.

    Directory of Open Access Journals (Sweden)

    Valeria Guidi

    Full Text Available Bacillus thuringiensis var. israelensis (Bti and Lysinibacillus sphaericus (Lsph are extensively used in mosquito control programs. These biocides are the active ingredients of a commercial larvicide. Quantitative data on the fate of both Bti and Lsph applied together for the control of mosquitoes in urban drainage structures such as catch basins are lacking. We evaluated the dynamics and persistence of Bti and Lsph spores released through their concomitant application in urban catch basins in southern Switzerland. Detection and quantification of spores over time in water and sludge samples from catch basins were carried out using quantitative real-time PCR targeting both cry4A and cry4B toxin genes for Bti and the binA gene for Lsph. After treatment, Bti and Lsph spores attained concentrations of 3.76 (± 0.08 and 4.13 (± 0.09 log ml(-1 in water, then decreased progressively over time, reaching baseline values. For both Bti and Lsph, spore levels in the order of 10(5 g(-1 were observed in the bottom sludge two days after the treatment and remained constant for the whole test period (275 days. Indigenous Lsph strains were isolated from previously untreated catch basins. A selection of those was genotyped using pulsed field gel electrophoresis of SmaI-digested chromosomal DNA, revealing that a subset of isolates were members of the clonal population of strain 2362. No safety issues related to the use of this biopesticide in the environment have been observed during this study, because no significant increase in the number of spores was seen during the long observation period. The isolation of native Lysinibacillus sphaericus strains belonging to the same clonal population as strain 2362 from catch basins never treated with Lsph-based products indicates that the use of a combination of Bti and Lsph for the control of mosquitoes does not introduce non-indigenous microorganisms in this area.

  5. Recombinant Bacillus subtilis spores expressing cholera toxin B subunit and Helicobacter pylori urease B confer protection against H. pylori in mice.

    Science.gov (United States)

    Zhou, Zhenwen; Dong, Hui; Huang, Yanmei; Yao, Shuwen; Liang, Bingshao; Xie, Yongqiang; Long, Yan; Mai, Jialiang; Gong, Sitang

    2017-01-01

    Helicobacter pylori infection is associated with chronic gastritis, peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. The limitations of current therapies for H. pylori infection include poor compliance and antibiotic resistance. Therefore, an effective anti-H. pylori vaccine would be an alternative or complement to antibiotic treatment. Urease B (UreB) is considered an ideal vaccine antigen against H. pylori infection. In this study, cholera toxin B subunit (CTB), a mucosal adjuvant, was used to enhance the immunogenicity of a novel Bacillus subtilis spore vaccine expressing CTB-UreB, along with the B. subtilis spore coat protein CotC as a fusion protein. Oral administration of B. subtilis spores expressing CotC-UreB or CotC-CTB-UreB led to increased levels of UreB-specific IgG in serum and UreB-specific IgA in faeces, as well as elevated levels of IL-10 and IFN-γ in splenocytes. In addition, oral administration of CotC-UreB or CotC-CTB-UreB spores induced significant reductions (80.0 and 90.5 %, respectively) in gastric H. pylori bacterial load (1.11±0.36×105 and 0.53±0.21×105 c.f.u., respectively) compared to that of the CotC control group (5.56±1.64×105 c.f.u., P<0.01). Moreover, CotC-CTB-UreB spores were significantly more effective at reducing the bacterial load than CotC-UreB spores (P<0.05). These results indicate that CotC-CTB-UreB-expressing B. subtilis spores are a potential vaccine candidate for the control of H. pylori infection.

  6. Protection of Penaeus monodon against white spot syndrome by continuous oral administration of a low concentration of Bacillus subtilis spores expressing the VP28 antigen.

    Science.gov (United States)

    Pham, K-C; Tran, H T T; Van Doan, C; Le, P H; Van Nguyen, A T; Nguyen, H A; Hong, H A; Cutting, S M; Phan, T-N

    2017-03-01

    In this study, Bacillus subtilis spores expressing a chimeric protein, CotB-VP28, were used as a probiotic vaccine to protect black tiger shrimps (Penaeus monodon) against white spot syndrome virus (WSSV) infection. Oral administration of pellets coated with CotB-VP28 spores (at ≥1 × 10(9 ) CFU per g pellet) to shrimps induced immune-relating phenoloxydase activity (PO) in shrimps after 14 days of feeding (prior challenge) and at day 3 post challenge (1·26 and 1·70 fold increase respectively). A 75% protection rate was obtained by continuous feeding of the spore-coated pellets at ≥1 × 10(9 ) CFU per g for 14 days prior to WSSV challenge and during all the postchallenge period. Even when the amount of CotB-VP28 spores in feed pellets was reduced down to ≥5 × 10(7)  CFU per g and ≥1 × 10(6)  CFU per g, relatively high protection rates of 70 and 67·5%, respectively, were still obtained. By contrast, feeding pellets without spores (untreated group) and with naked spores (PY79 group) at ≥1 × 10(9)  CFU per g could not protect shrimps against WSSV. These data suggest that supplementation of CotB-VP28 spores at low dose of ≥1 × 10(6)  CFU per g could be effective as a prophylactic treatment of WSS for black tiger shrimps.

  7. Inactivation of Spores of Bacillus Species by Wet Heat: Studies on Single Spores Using Laser Tweezers Taman Spectroscopy

    Science.gov (United States)

    2013-02-01

    germination using phase contrast and fluorescence microscopy, Raman spectroscopy and optical tweezers, Nature Protocols , (04 2011): . doi: 05/11...multiple individual spores [ Nature Protocols , 6, 625 (2011)]. (1e) We developed a multiple-trap laser tweezers Raman spectroscopy (LTRS) array for

  8. Workshop report: modeling the molecular mechanism of bacterial spore germination and elucidating reasons for germination heterogeneity.

    Science.gov (United States)

    Indest, Karl J; Buchholz, Wallace G; Faeder, Jim R; Setlow, Peter

    2009-08-01

    Over the course of 2 days, top researchers in the fields of bacterial spore biology and computational biology discussed approaches to determine the cause of spore germination heterogeneity. Biological and mathematical data gaps were identified, and experimental approaches and computational strategies for modeling spore germination were presented and evaluated. As a result of these interactions, future research directions were defined, the outcome of which should result in a robust model to help define the molecular mechanism(s) of spore germination. Mechanistic understanding of germination will be instrumental for developing novel sterilization, treatment, and decontamination strategies to mitigate threats posed by spores.

  9. Comparison of the properties of Bacillus subtilis spores made in liquid or on agar plates.

    Science.gov (United States)

    Rose, R; Setlow, B; Monroe, A; Mallozzi, M; Driks, A; Setlow, P

    2007-09-01

    To compare the properties of the spores of Bacillus subtilis prepared in liquid and on plates. The spores of B. subtilis were prepared at 37 degrees C using a nutrient exhaustion medium either in liquid or on agar plates. The levels of core water, dipicolinic acid (DPA) and small, acid-soluble spore proteins (SASP) were essentially identical in spores made in liquid or on plates. Spores prepared in liquid were killed approximately threefold more rapidly at 90 degrees C in water than the spores prepared on plates, and the spores prepared in liquid were more sensitive to nitrous acid and a diluted stable superoxidized water. Spores prepared in liquid also germinated more rapidly with several agents than those prepared on plates. Pellets of spores prepared on plates were darker than spores prepared in liquid, and spores prepared in liquid had more readily extracted coat protein. However, there were no major differences in the relative levels of individual coat proteins or the cross-linking of the coat protein GerQ in the two types of spores, although the inner membrane of spores prepared on plates had a higher ratio of anteiso- to iso-fatty acids. The preparation in liquid yielded spores with some different properties than those made on agar plates. Spores made in liquid had lower resistance to heat and several chemicals, and germinated more readily with several agents. There were also differences in the composition of the inner membrane of spores prepared under these two conditions. However, there were no major differences in the levels of DPA, core water, SASP and individual coat proteins or the cross-linking of a coat protein in spores made in liquid and on plates. This work demonstrates that the preparation method can affect the resistance and germination properties of bacterial spores, even if an identical medium and temperature are used. Evidence was also obtained consistent with the role of the inner membrane in spore resistance and germination, and that some

  10. Production of Soy Sauce Koji Mold Spore Inoculum in Plastic Bags

    OpenAIRE

    Lotong, N.; Suwanarit, P.

    1983-01-01

    An innovation is described for producing soy sauce koji mold spore inoculum by using inexpensive autoclavable plastic bags and reuseable plastic enclosures to make culture vessels. After growth, the spore mass could be dried and packaged in the same bag after removing the enclosure. Broken rice was used as the substrate for mold cultivation. Viable spore counts of 109 spores per g were obtained under optimal conditions. After drying at 50°C for 6 h, the moisture content of the spore mass decr...

  11. Effect of Ganoderma lucidum spore on expression of insulin-like growth factor-1, nuclear factor-kappa B, and neuronal apoptosis in the epileptic rat brain

    Institute of Scientific and Technical Information of China (English)

    Shuang Zhao; Shuqiu Wang; Shengchang Zhang; Fafang Li

    2008-01-01

    apoptotic cells were observed in the hippocampus and cerebral cortex,expression of NF-κB/P65 was lower, and immunoreactivity to IGF-1 increased more distinctly, compared with the epilepsy group. In addition, seizure latency was longer on 17, 21, and 25 days post-PTZ treatment in the Ganoderma lucidum spore powder group, compared with the epilepsy group (P < 0.05 0.01).CONCLUSION: Ganoderma lucidum spore powder down-regulated expression of NF-κB in brain tissues of rats with PTZ-induced epilepsy, increased immunoreactivity to IGF-1, and inhibited neuronal apoptosis.These results indicated that Ganoderma lucidum spore powder has a neuroprotective effect.

  12. Arabitol and mannitol as tracers for the quantification of airborne fungal spores

    Science.gov (United States)

    Bauer, Heidi; Claeys, Magda; Vermeylen, Reinhilde; Schueller, Elisabeth; Weinke, Gert; Berger, Anna; Puxbaum, Hans

    Fungal spores constitute a sizeable fraction of coarse organic carbon (OC) in the atmospheric aerosol. In order to avoid tedious spore count methods, tracers for quantifying the spore-OC in atmospheric aerosol are sought. Arabitol and mannitol have been proposed as such tracers, since no other emission sources for these compounds have been reported. By parallel investigations of spore counts and tracer determinations from PM 10 filter samples we could derive quantitative relationships between the amounts of tracer compounds and the numbers of spores in the atmosphere for different sites in the area of Vienna. We obtained over all average relationships of 1.2 pg arabitol spore -1, with a range of 0.8-1.8, and 1.7 pg mannitol spore -1, with a range of 1.2-2.4, with a clear site dependence. Thus, using these conversion factors from spore counts to spore-OC and spore-mass, along with analytical data for arabitol or mannitol in filter samples, the contribution of fungal spores to the OC and to the mass balance of atmospheric aerosol particles can be estimated.

  13. Architecture and High-Resolution Structure of Bacillus thuringiensis and Bacillus cereus Spore Coat Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; Leighton, T; Wheeler, K; Malkin, A

    2005-02-18

    We have utilized atomic force microscopy (AFM) to visualize the native surface topology and ultrastructure of Bacillus thuringiensis and Bacillus cereus spores in water and in air. AFM was able to resolve the nanostructure of the exosporium and three distinctive classes of appendages. Removal of the exosporium exposed either a hexagonal honeycomb layer (B. thuringiensis) or a rodlet outer spore coat layer (B. cereus). Removal of the rodlet structure from B. cereus spores revealed an underlying honeycomb layer similar to that observed with B. thuringiensis spores. The periodicity of the rodlet structure on the outer spore coat of B. cereus was {approx}8 nm, and the length of the rodlets was limited to the cross-patched domain structure of this layer to {approx}200 nm. The lattice constant of the honeycomb structures was {approx}9 nm for both B. cereus and B. thuringiensis spores. Both honeycomb structures were composed of multiple, disoriented domains with distinct boundaries. Our results demonstrate that variations in storage and preparation procedures result in architectural changes in individual spore surfaces, which establish AFM as a useful tool for evaluation of preparation and processing ''fingerprints'' of bacterial spores. These results establish that high-resolution AFM has the capacity to reveal species-specific assembly and nanometer scale structure of spore surfaces. These species-specific spore surface structural variations are correlated with sequence divergences in a spore core structural protein SspE.

  14. MECHANISM OF FUSARIUM TRICINCTUM (CORDA SACC. SPORE INACTIVATION BY CHLORINE DIOXIDE

    Directory of Open Access Journals (Sweden)

    Zhao Chen

    2015-06-01

    Full Text Available The mechanism of Fusarium tricinctum (Corda Sacc. spore inactivation by chlorine dioxide (ClO2 was investigated. During F. tricinctum spore inactivation by ClO2, protein, DNA, and metal ion leakage, enzyme activity, and cell ultrastructure were examined. Protein and DNA leakages were not detected, while there were metal ion leakages of K+, Ca2+, and Mg2+, which were well-correlated with the inactivation rate. The enzyme activities of glucose-6-phosphate dehydrogenase, citrate synthase, and phosphofructokinase were inhibited and were also well-correlated with the inactivation rate. Electron micrographs showed the ultrastructural modifications of spores and demonstrated that spores were heavily distorted and collapsed from their regular structure. Spore surface damage and disruption in inner components was also severe. The metal ion leakage, the inhibition of enzyme activities, and the damage of spore structure were significant in F. tricinctum spore inactivation by ClO2.

  15. In vitro high-resolution structural dynamics of single germinating bacterial spores

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; Leighton, T; Wheeler, K; Malkin, A

    2006-11-14

    Although significant progress has been achieved in understanding the genetic and biochemical bases of the spore germination process, the structural basis for breaking the dormant spore state remains poorly understood. We have used atomic force microscopy (AFM) to probe the high-resolution structural dynamics of single Bacillus atrophaeus spores germinating under native conditions. Here we show that AFM can reveal previously unrecognized germination-induced alterations in spore coat architecture and topology as well as the disassembly of outer spore coat rodlet structures. These results and previous studies in other microorganisms suggest that the spore coat rodlets are structurally similar to amyloid fibrils. AFM analysis of the nascent surface of the emerging germ cell revealed a porous network of peptidoglycan fibers. The results are consistent with a honeycomb model structure for synthetic peptidoglycan oligomers determined by nuclear magnetic resonance. AFM is a promising experimental tool for investigating the morphogenesis of spore germination and cell wall peptidoglycan structure.

  16. In vitro high-resolution structural dynamics of single germinating bacterial spores

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Livermore National Laboratory

    2006-12-11

    Although significant progress has been achieved in understanding the genetic and biochemical bases of the spore germination process, the structural basis for breaking the dormant spore state remains poorly understood. We have used atomic force microscopy (AFM) to probe the high-resolution structural dynamics of single Bacillus atrophaeus spores germinating under native conditions. Here we show that AFM can reveal previously unrecognized germination-induced alterations in spore coat architecture and topology as well as the disassembly of outer spore coat rodlet structures. These results and previous studies in other microorganisms suggest that the spore coat rodlets are structurally similar to amyloid fibrils. AFM analysis of the nascent surface of the emerging germ cell revealed a porous network of peptidoglycan fibers. The results are consistent with a honeycomb model structure for synthetic peptidoglycan oligomers determined by nuclear magnetic resonance. AFM is a promising experimental tool for investigating the morphogenesis of spore germination and cell wall peptidoglycan structure.

  17. Production of soy sauce koji mold spore inoculum in plastic bags.

    Science.gov (United States)

    Lotong, N; Suwanarit, P

    1983-11-01

    An innovation is described for producing soy sauce koji mold spore inoculum by using inexpensive autoclavable plastic bags and reuseable plastic enclosures to make culture vessels. After growth, the spore mass could be dried and packaged in the same bag after removing the enclosure. Broken rice was used as the substrate for mold cultivation. Viable spore counts of 10 spores per g were obtained under optimal conditions. After drying at 50 degrees C for 6 h, the moisture content of the spore mass decreased from 35.22 to 6.32% with no significant effect on spore viability. The dry spores could be stored in the refrigerator or at room temperature for at least 3 months.

  18. Development of Spore Protein of Myxobolus koi as an Immunostimulant for Prevent of Myxobolusis on Gold Fish (Cyprinus carpio Linn) by Oral Immunisation

    Science.gov (United States)

    Mahasri, Gunanti

    2017-02-01

    Production of Gold fish (Cyprinus carpio Linn) in Indonesia has always increased from 2013 to 2015 year by year with increasing average 2% per year. The amount of production was respectively 571.892 tonnes, 1129.273 tonnes, and 1186.674 tonnes. There were almost no problems to sale of gold fish because it had a good enough prospect. The aims of this research were Isolation of spore protein of Myxobolus koi by using SDS-PAGE to analyze immun respons and survival rate gold fish that immunized with spore protein of Myxobolus koi. The method of this research used experimental method, and belonged to 4 treatments that are: Controle = the group of gold fish not immunized with protein spore of Myxobolus koi neither infected by Myxobolus koi (T1). The group immunized and infested by spore of Myxobolus koi (T2), The group which immunized and not infested by Myxobolus koi (T3), and The group only infested by Myxobolus koi (T4). The dose of immunostimulant was 5 ml in 1 kg of food. The result showed that there were two bands of whole spore protein with molecule weight (MW) 150 kDa and 72 kDa and one band of crude protein Myxobolus koi with molecule weight 73 kD and the optical density point was 0.132 on the first day and increased to 0.769 on the 56 th day. The result also showed that the immun respons and survival rate increased from 27% to 86% in chellence test. The protein spore of Myxobolus koi can used to develops material for immunostimulant and to prevent the myxobolusis.

  19. Nanoscale structural and mechanical analysis of Bacillus anthracis spores inactivated with rapid dry heating.

    Science.gov (United States)

    Xing, Yun; Li, Alex; Felker, Daniel L; Burggraf, Larry W

    2014-03-01

    Effective killing of Bacillus anthracis spores is of paramount importance to antibioterrorism, food safety, environmental protection, and the medical device industry. Thus, a deeper understanding of the mechanisms of spore resistance and inactivation is highly desired for developing new strategies or improving the known methods for spore destruction. Previous studies have shown that spore inactivation mechanisms differ considerably depending upon the killing agents, such as heat (wet heat, dry heat), UV, ionizing radiation, and chemicals. It is believed that wet heat kills spores by inactivating critical enzymes, while dry heat kills spores by damaging their DNA. Many studies have focused on the biochemical aspects of spore inactivation by dry heat; few have investigated structural damages and changes in spore mechanical properties. In this study, we have inactivated Bacillus anthracis spores with rapid dry heating and performed nanoscale topographical and mechanical analysis of inactivated spores using atomic force microscopy (AFM). Our results revealed significant changes in spore morphology and nanomechanical properties after heat inactivation. In addition, we also found that these changes were different under different heating conditions that produced similar inactivation probabilities (high temperature for short exposure time versus low temperature for long exposure time). We attributed the differences to the differential thermal and mechanical stresses in the spore. The buildup of internal thermal and mechanical stresses may become prominent only in ultrafast, high-temperature heat inactivation when the experimental timescale is too short for heat-generated vapor to efficiently escape from the spore. Our results thus provide direct, visual evidences of the importance of thermal stresses and heat and mass transfer to spore inactivation by very rapid dry heating.

  20. Effect of high hydrostatic pressure on mycelial development, spore viability and enzyme activity of Penicillium Roqueforti.

    Science.gov (United States)

    Martínez-Rodríguez, Yamile; Acosta-Muñiz, Carlos; Olivas, Guadalupe I; Guerrero-Beltrán, José; Rodrigo-Aliaga, Dolores; Mujica-Paz, Hugo; Welti-Chanes, Jorge; Sepulveda, David R

    2014-01-03

    This study investigated the effect of high hydrostatic pressure treatments on mycelial development, spore viability, and total proteolytic and lipolytic activity of Penicillium roqueforti PV-LYO 10 D. Fungus growing in liquid medium was pressure-treated at 300, 400, and 500 MPa for 10 min at 20°C following seven days of incubation at 25°C and analyzed periodically up to day 9 after treatments to evaluate the effect on fungal growth. Mycelial mass of P. roqueforti was significantly affected at all pressure treatments evaluated, being 15.48%, 22.28%, 30.03%, and 12.53% lower than controls on day 1, 3, 6, and 9 after 300 MPa treatment, respectively. In a similar way, at 400 and 500 MPa, mycelial mass was 31.08% and 60.34% lower than controls one day after treatments and 49.74% and 80.85% lower on day 9, respectively. The viability of P. roqueforti spores decreased by 36.53% at 300 MPa, and complete inactivation took place at ≥400 MPa from an initial count of 7 log cfu/mL. Total proteolytic activity was not significantly affected at 300 MPa but was reduced by 18.22% at 400 MPa and by 43.18% at 500 MPa. Total lipolytic activity also decreased as the intensity of the pressure treatments increased. 21.69%, 39.12%, and 56.26% activity reductions were observed when treatments of 300, 400 and 500 MPa were applied, respectively. The results from this study show that pressure treatments are able to control growth, inactivate spores, and alter enzyme activity of P. roqueforti, which could be of interest in extending the shelf-life of blue-veined cheeses and other food products. © 2013.

  1. Effect of Carbon and Nitrogen Availability on Metabolism of Amino Acids in Germinating Spores of Arbuscular Mycorrhizal Fungi

    Institute of Scientific and Technical Information of China (English)

    JIN Hai-Ru; JIANG Dong-Hua; ZHANG Ping-Hua

    2011-01-01

    The effects of carbon (C) and nitrogen (N) sources on N utilization and biosynthesis of amino acids were examined in the germinating spores of the arbuscular mycorrhizal (AM) fungus Glomus intraradices Schenck & Smith after exposure to various N substrates,CO2,glucose,and/or root exudates.The N uptake and de novo biosynthesis of amino acids were analyzed using stable isotopic labeling with mass spectrometric detection.High-performance liquid chromatography-based analysis was used to measure amino acid levels.In the absence of exogenous N sources and in the presence of 25 mL L-1 CO2,the germinating AM fungal spores utilized internal N storage as well as C skeletons derived from the degradation of storage lipids to biosynthesize the free amino acids,in which serine and glycine were produced predominantly.The concentrations of internal amino acids increased gradually as the germination time increased from 0 to 1 or 2 weeks.However,asparagine and glutamine declined to the low levels; both degraded to provide the biosynthesis of other amino acids with C and N donors.The availability of exogenous inorganic N (ammonium and nitrate) and organic N (urea,arginine,and glutamine) to the AM fungal spores using only CO2 for germination generated more than 5 times more internal free amino acids than those in the absence of exogenous N.A supply of exogenous nitrate to the AM fungal spores with only CO2 gave rise to more than 10 times more asparagine than that without exogenous N.In contrast,the extra supply of exogenous glucose to the AM fungal spores generated a significant enhancement in the uptake of exogenous N sources,with more than 3 times more free amino acids being produced than those supplied with only exogenous CO2.Meanwhile,arginine was the most abundant free amino acid produced and it was incorporated into the proteins of AM fungal spores to serve as an N storage compound.

  2. Distribution of sterols in the fungi. I - Fungal spores

    Science.gov (United States)

    Weete, J. D.; Laseter, J. L.

    1974-01-01

    Mass spectrometry was used to examine freely extractable sterols from spores of several species of fungi. Ergosterol was the most common sterol produced by any individual species, but it was completely absent from two species belonging to apparently distantly related groups of fungi: the aquatic Phycomycetes and the rust fungi. This fact could have taxonomic or phylogenetic implications. The use of glass capillary columns in the resolution of the sterols is shown to eliminate some of the difficulty inherent in this process.

  3. Distribution of sterols in the fungi. I - Fungal spores

    Science.gov (United States)

    Weete, J. D.; Laseter, J. L.

    1974-01-01

    Mass spectrometry was used to examine freely extractable sterols from spores of several species of fungi. Ergosterol was the most common sterol produced by any individual species, but it was completely absent from two species belonging to apparently distantly related groups of fungi: the aquatic Phycomycetes and the rust fungi. This fact could have taxonomic or phylogenetic implications. The use of glass capillary columns in the resolution of the sterols is shown to eliminate some of the difficulty inherent in this process.

  4. 14C Analysis of Protein Extracts from Bacillus Spores

    Science.gov (United States)

    Cappucio, Jenny A.; Sarachine Falso, Miranda J.; Kashgarian, Michaele; Buchholz, Bruce A.

    2014-01-01

    Investigators of bioagent incidents or interdicted materials need validated, independent analytical methods that will allow them to distinguish between recently made bioagent samples versus material drawn from the archives of a historical program. Heterotrophic bacteria convert the carbon in their food sources, growth substrate or culture media, into the biomolecules they need. The F14C (fraction modern radiocarbon) of a variety of media, Bacillus spores, and separated proteins from Bacillus spores was measured by accelerator mass spectrometry (AMS). AMS precisely measures F14C values of biological materials and has been used to date the synthesis of biomaterials over the bomb pulse era (1955 to present). The F14C of Bacillus spores reflects the radiocarbon content of the media in which they were grown. In a survey of commercial media we found that the F14C value indicated that carbon sources for the media were alive within about a year of the date of manufacture and generally of terrestrial origin. Hence, bacteria and their products can be dated using their 14C signature. Bacillus spore samples were generated onsite with defined media and carbon free purification and also obtained from archived material. Using mechanical lysis and a variety of washes with carbon free acids and bases, contaminant carbon was removed from soluble proteins to enable accurate 14C bomb-pulse dating. Since media is contemporary, 14C bomb-pulse dating of isolated soluble proteins can be used to distinguish between historical archives of bioagents and those produced from recent media. PMID:24814329

  5. Solid-Phase Capture of Proteins, Spores, and Bacteria†

    OpenAIRE

    Weimer, B.C.; Walsh, M. K.; Beer, C.; Koka, R.; X. Wang

    2001-01-01

    Current methods for the detection of pathogens in food and water samples generally require a preenrichment step that allows selective enrichment of the test organism. The objective of this research was to eliminate an enrichment step to allow detection of bacteria directly in food and water samples in 30 min. A high-flow-rate, fluidized bed to capture and concentrate large (bacteria and spores) and small (protein) molecules was developed. This format, ImmunoFlow, is volume independent and use...

  6. Processing, Assembly and Localization of a Bacillus anthracis Spore Protein

    Science.gov (United States)

    2010-01-01

    10.1099/ mic .0.033407-0 174 033407 Printed in Great Britain Approved for public release. Distribution is unlimited Report Documentation Page Form...on LB agar plates to assay viable cells. In vivo challenges. Female Hartley guinea pigs (350–400 g) were obtained from Charles River Laboratories...Guinea pigs were challenged intramuscularly (Fellows et al., 2001) by injection of 200 ml of heat-activated spores suspended in water. The animals were

  7. Ribosomal ribonucleic acid maturation during bacterial spore germination.

    Science.gov (United States)

    Bleyman, M; Woese, C

    1969-01-01

    All the ribosomal ribonucleic acid made during the early stages of germination of spores of Bacillus subtilis is of the "precursor" type, i.e., that type appearing in the incomplete forms of the ribosome. Shortly before the onset of deoxyribonucleic acid synthesis in germination, this precursor ribonucleic acid changed to the mature ribosomal ribonucleic acid characteristic of the 30S and 50S ribosomal subunits.

  8. Indole and 3-indolylacetonitrile inhibit spore maturation in Paenibacillus alvei

    Directory of Open Access Journals (Sweden)

    Cho Moo

    2011-05-01

    Full Text Available Abstract Background Bacteria use diverse signaling molecules to ensure the survival of the species in environmental niches. A variety of both Gram-positive and Gram-negative bacteria produce large quantities of indole that functions as an intercellular signal controlling diverse aspects of bacterial physiology. Results In this study, we sought a novel role of indole in a Gram-positive bacteria Paenibacillus alvei that can produce extracellular indole at a concentration of up to 300 μM in the stationary phase in Luria-Bertani medium. Unlike previous studies, our data show that the production of indole in P. alvei is strictly controlled by catabolite repression since the addition of glucose and glycerol completely turns off the indole production. The addition of exogenous indole markedly inhibits the heat resistance of P. alvei without affecting cell growth. Observation of cell morphology with electron microscopy shows that indole inhibits the development of spore coats and cortex in P. alvei. As a result of the immature spore formation of P. alvei, indole also decreases P. alvei survival when exposed to antibiotics, low pH, and ethanol. Additionally, indole derivatives also influence the heat resistance; for example, a plant auxin, 3-indolylacetonitrile dramatically (2900-fold decreased the heat resistance of P. alvei, while another auxin 3-indoleacetic acid had a less significant influence on the heat resistance of P. alvei. Conclusions Together, our results demonstrate that indole and plant auxin 3-indolylacetonitrile inhibit spore maturation of P. alvei and that 3-indolylacetonitrile presents an opportunity for the control of heat and antimicrobial resistant spores of Gram-positive bacteria.

  9. Variation of desiccation tolerance and longevity in fern spores.

    Science.gov (United States)

    Ballesteros, Daniel; Hill, Lisa M; Walters, Christina

    2017-04-01

    This work contributes to the understanding of plant cell responses to extreme water stress when it is applied at different intensity and duration. Fern spores are used to explore survival at relative humidity (RH)desiccation damage occurs in desiccation tolerant cells, and that it is expressed as a time-dependent response, otherwise known as aging. Copyright © 2017 Elsevier GmbH. All rights reserved.

  10. Assessing the usefulness of clostridia spores for evaluating sewage sludge hygienization.

    Science.gov (United States)

    Martín-Díaz, Julia; Ruiz-Hernando, Maria; Astals, Sergi; Lucena, Francisco

    2017-02-01

    The capability of clostridia spores to act as pathogen indicators in sewage sludge treatment was investigated. Sulfite-reducing clostridia and E. coli levels were monitored during waste activated sludge pre-treatments (alkali and ultrasound) and its subsequent mesophilic anaerobic digestion. E. coli was maintained or reduced depending on treatment type and intensity. However, alkali pre-treatment (35.3gNaOH/kgTS) by itself and alkali (157gNaOH/kgTS) and ultrasound (27,000kJ/kgTS) pre-treatments followed by anaerobic digestion provoked reproducible clostridia increases. Specifically, up to 2.7log10 after 35.3gNaOH/kgTS pre-treatment and up to 1.9 and 1.1log10 after digesting the 157gNaOH/kg TS and 27,000kJ/kgTS pre-treated sludge, respectively. Having rejected the hypotheses of sporulation and floc dissipation, the most plausible explanation for these clostridia increases is re-growth. These results question the suitability of clostridia spores as indicators of sludge treatment and other biological treatments where clostridia may have a role.

  11. Investigation of ice-assisted sonication on the microstructure and chemical quality of Ganoderma lucidum spores.

    Science.gov (United States)

    Zhao, Ding; Chang, Ming-Wei; Li, Jing-Song; Suen, William; Huang, Jie

    2014-11-01

    Ganoderma lucidum spores (GLS) are well known for disease treatment and vitality enhancement, and have been shown to contain a variety of bioactive components, such as polysaccharides and triterpenes. However, the resilient bilayer sporoderm structure of GLS restricts the release of bioactive components and limits its complete pharmacological effects. The current study was aimed to improve the quality of GLS by means of a customized sonication technique, particularly, the effect of sonication processing parameters on GLS-breaking efficiencies was investigated. Significant morphological changes, such as cracked, fractured, and disintegrated GLS were observed using scanning electron microscopy (SEM) after sonication treatment. The performance for breaking GLS sporoderm was obtained at ultrasonic power density of 23.7 W/cm(2) , duty cycle 100%, and 90-min processing time. Through the combination of sonication in an ice bath, sporoderm breaking efficiency can be further increased from 45% to almost 75%. FTIR analysis revealed an increase in bioactive components of polysaccharide, protein, and fatty acid from the sonication processed GLS when compared to ground spores available commercially. The current results indicated that the ice bath combined sonication method is more effective in delivering GLS ingredients and could be an economic technique for the production of high-quality broken sporoderm GLS.

  12. Unlocking the Sporicidal Potential of Ethanol: Induced Sporicidal Activity of Ethanol against Clostridium difficile and Bacillus Spores under Altered Physical and Chemical Conditions.

    Directory of Open Access Journals (Sweden)

    Michelle M Nerandzic

    Full Text Available Due to their efficacy and convenience, alcohol-based hand sanitizers have been widely adopted as the primary method of hand hygiene in healthcare settings. However, alcohols lack activity against bacterial spores produced by pathogens such as Clostridium difficile and Bacillus anthracis. We hypothesized that sporicidal activity could be induced in alcohols through alteration of physical or chemical conditions that have been shown to degrade or allow penetration of spore coats.Acidification, alkalinization, and heating of ethanol induced rapid sporicidal activity against C. difficile, and to a lesser extent Bacillus thuringiensis and Bacillus subtilis. The sporicidal activity of acidified ethanol was enhanced by increasing ionic strength and mild elevations in temperature. On skin, sporicidal ethanol formulations were as effective as soap and water hand washing in reducing levels of C. difficile spores.These findings demonstrate that novel ethanol-based sporicidal hand hygiene formulations can be developed through alteration of physical and chemical conditions.

  13. Unlocking the Sporicidal Potential of Ethanol: Induced Sporicidal Activity of Ethanol against Clostridium difficile and Bacillus Spores under Altered Physical and Chemical Conditions

    Science.gov (United States)

    Nerandzic, Michelle M.; Sunkesula, Venkata C. K.; C., Thriveen Sankar; Setlow, Peter; Donskey, Curtis J.

    2015-01-01

    Background Due to their efficacy and convenience, alcohol-based hand sanitizers have been widely adopted as the primary method of hand hygiene in healthcare settings. However, alcohols lack activity against bacterial spores produced by pathogens such as Clostridium difficile and Bacillus anthracis. We hypothesized that sporicidal activity could be induced in alcohols through alteration of physical or chemical conditions that have been shown to degrade or allow penetration of spore coats. Principal Findings Acidification, alkalinization, and heating of ethanol induced rapid sporicidal activity against C. difficile, and to a lesser extent Bacillus thuringiensis and Bacillus subtilis. The sporicidal activity of acidified ethanol was enhanced by increasing ionic strength and mild elevations in temperature. On skin, sporicidal ethanol formulations were as effective as soap and water hand washing in reducing levels of C. difficile spores. Conclusions These findings demonstrate that novel ethanol-based sporicidal hand hygiene formulations can be developed through alteration of physical and chemical conditions. PMID:26177038

  14. Pollen and spores as biological recorders of past ultraviolet irradiance.

    Science.gov (United States)

    Jardine, Phillip E; Fraser, Wesley T; Lomax, Barry H; Sephton, Mark A; Shanahan, Timothy M; Miller, Charlotte S; Gosling, William D

    2016-12-15

    Solar ultraviolet (UV) irradiance is a key driver of climatic and biotic change. Ultraviolet irradiance modulates stratospheric warming and ozone production, and influences the biosphere from ecosystem-level processes through to the largest scale patterns of diversification and extinction. Yet our understanding of ultraviolet irradiance is limited because no method has been validated to reconstruct its flux over timescales relevant to climatic or biotic processes. Here, we show that a recently developed proxy for ultraviolet irradiance based on spore and pollen chemistry can be used over long (10(5) years) timescales. Firstly we demonstrate that spatial variations in spore and pollen chemistry correlate with known latitudinal solar irradiance gradients. Using this relationship we provide a reconstruction of past changes in solar irradiance based on the pollen record from Lake Bosumtwi in Ghana. As anticipated, variations in the chemistry of grass pollen from the Lake Bosumtwi record show a link to multiple orbital precessional cycles (19-21 thousand years). By providing a unique, local proxy for broad spectrum solar irradiance, the chemical analysis of spores and pollen offers unprecedented opportunities to decouple solar variability, climate and vegetation change through geologic time and a new proxy with which to probe the Earth system.

  15. Setting risk-informed environmental standards for Bacillus anthracis spores.

    Science.gov (United States)

    Hong, Tao; Gurian, Patrick L; Ward, Nicholas F Dudley

    2010-10-01

    In many cases, human health risk from biological agents is associated with aerosol exposures. Because air concentrations decline rapidly after a release, it may be necessary to use concentrations found in other environmental media to infer future or past aerosol exposures. This article presents an approach for linking environmental concentrations of Bacillus. anthracis (B. anthracis) spores on walls, floors, ventilation system filters, and in human nasal passages with human health risk from exposure to B. anthracis spores. This approach is then used to calculate example values of risk-informed concentration standards for both retrospective risk mitigation (e.g., prophylactic antibiotics) and prospective risk mitigation (e.g., environmental clean up and reoccupancy). A large number of assumptions are required to calculate these values, and the resulting values have large uncertainties associated with them. The values calculated here suggest that documenting compliance with risks in the range of 10(-4) to 10(-6) would be challenging for small diameter (respirable) spore particles. For less stringent risk targets and for releases of larger diameter particles (which are less respirable and hence less hazardous), environmental sampling would be more promising.

  16. Long-term survival of bacterial spores in space

    Science.gov (United States)

    Horneck, G.; Bucker, H.; Reitz, G.

    1994-01-01

    On board of the NASA Long Duration Exposure Facility (LDEF), spores of Bacillus subtilis in monolayers (10(exp 6)/sample) or multilayers (10(exp 8)/sample) were exposed to the space environment for nearly six years and their survival was analyzed after retrieval. The response to space parameters, such as vacuum (10(exp -6) Pa), solar electromagnetic radiation up to the highly energetic vacuum-ultraviolet range 10(exp 9) J/sq m) and/or cosmic radiation (4.8 Gy), was studied and compared to the results of a simultaneously running ground control experiment. If shielded against solar ultraviolet (UV)-radiation, up to 80% of spores in multilayers survive in space. Solar UV-radiation, being the most deleterious parameter of space, reduces survival by 4 orders of magnitude or more. However, up to 10(exp 4) viable spores were still recovered, even in completely unprotected samples. Substances, such as glucose or buffer salts serve as chemical protectants. With this 6 year study in space, experimental data are provided to the discussion on the likelihood of 'Panspermia'.

  17. Mutagenesis of Bacillus subtilis spores exposed to simulated space environment

    Science.gov (United States)

    Munakata, N.; Natsume, T.; Takahashi, K.; Hieda, K.; Panitz, C.; Horneck, G.

    Bacterial spores can endure in a variety of extreme earthly environments. However, some conditions encountered during the space flight could be detrimental to DNA in the spore, delimiting the possibility of transpermia. We investigate the genetic consequences of the exposure to space environments in a series of preflight simulation project of EXPOSE. Using Bacillus subtilis spores of repair-proficient HA101 and repair-deficient TKJ6312 strains, the mutations conferring resistance to rifampicin were detected, isolated and sequenced. Most of the mutations were located in a N-terminal region of the rpoB gene encoding RNA polymerase beta-subunit. Among several potentially mutagenic factors, high vacuum, UV radiation, heat, and accelerated heavy ions induced mutations with varying efficiencies. A majority of mutations induced by vacuum exposure carried a tandem double-base change (CA to TT) at a unique sequence context of TCAGC. Results indicate that the vacuum and high temperature may act synergistically for the induction of mutations.

  18. Pollen and spores as biological recorders of past ultraviolet irradiance

    Science.gov (United States)

    Jardine, Phillip E.; Fraser, Wesley T.; Lomax, Barry H.; Sephton, Mark A.; Shanahan, Timothy M.; Miller, Charlotte S.; Gosling, William D.

    2016-12-01

    Solar ultraviolet (UV) irradiance is a key driver of climatic and biotic change. Ultraviolet irradiance modulates stratospheric warming and ozone production, and influences the biosphere from ecosystem-level processes through to the largest scale patterns of diversification and extinction. Yet our understanding of ultraviolet irradiance is limited because no method has been validated to reconstruct its flux over timescales relevant to climatic or biotic processes. Here, we show that a recently developed proxy for ultraviolet irradiance based on spore and pollen chemistry can be used over long (105 years) timescales. Firstly we demonstrate that spatial variations in spore and pollen chemistry correlate with known latitudinal solar irradiance gradients. Using this relationship we provide a reconstruction of past changes in solar irradiance based on the pollen record from Lake Bosumtwi in Ghana. As anticipated, variations in the chemistry of grass pollen from the Lake Bosumtwi record show a link to multiple orbital precessional cycles (19–21 thousand years). By providing a unique, local proxy for broad spectrum solar irradiance, the chemical analysis of spores and pollen offers unprecedented opportunities to decouple solar variability, climate and vegetation change through geologic time and a new proxy with which to probe the Earth system.

  19. In vitro and in vivo analyses of the Bacillus anthracis spore cortex lytic protein SleL

    OpenAIRE

    2012-01-01

    The bacterial endospore is the most resilient biological structure known. Multiple protective integument layers shield the spore core and promote spore dehydration and dormancy. Dormancy is broken when a spore germinates and becomes a metabolically active vegetative cell. Germination requires the breakdown of a modified layer of peptidoglycan (PG) known as the spore cortex. This study reports in vitro and in vivo analyses of the Bacillus anthracis SleL protein. SleL is a spore cortex lytic en...

  20. Spore populations among bulk tank raw milk and dairy powders are significantly different.

    Science.gov (United States)

    Miller, Rachel A; Kent, David J; Watterson, Matthew J; Boor, Kathryn J; Martin, Nicole H; Wiedmann, Martin

    2015-12-01

    To accommodate stringent spore limits mandated for the export of dairy powders, a more thorough understanding of the spore species present will be necessary to develop prospective strategies to identify and reduce sources (i.e., raw materials or in-plant) of contamination. We characterized 1,523 spore isolates obtained from bulk tank raw milk (n=33 farms) and samples collected from 4 different dairy powder-processing plants producing acid whey, nonfat dry milk, sweet whey, or whey protein concentrate 80. The spores isolated comprised 12 genera, at least 44 species, and 216 rpoB allelic types. Bacillus and Geobacillus represented the most commonly isolated spore genera (approximately 68.9 and 12.1%, respectively, of all spore isolates). Whereas Bacillus licheniformis was isolated from samples collected from all plants and farms, Geobacillus spp. were isolated from samples from 3 out of 4 plants and just 1 out of 33 farms. We found significant differences between the spore population isolated from bulk tank raw milk and those isolated from dairy powder plant samples, except samples from the plant producing acid whey. A comparison of spore species isolated from raw materials and finished powders showed that although certain species, such as B. licheniformis, were found in both raw and finished product samples, other species, such as Geobacillus spp. and Anoxybacillus spp., were more frequently isolated from finished powders. Importantly, we found that 8 out of 12 genera were isolated from at least 2 different spore count methods, suggesting that some spore count methods may provide redundant information if used in parallel. Together, our results suggest that (1) Bacillus and Geobacillus are the predominant spore contaminants in a variety of dairy powders, implying that future research efforts targeted at elucidating approaches to reduce levels of spores in dairy powders should focus on controlling levels of spore isolates from these genera; and (2) the spore

  1. Characterization of bacterial spore germination using integrated phase contrast microscopy, Raman spectroscopy, and optical tweezers.

    Science.gov (United States)

    Kong, Lingbo; Zhang, Pengfei; Setlow, Peter; Li, Yong-Qing

    2010-05-01

    We present a methodology that combines external phase contrast microscopy, Raman spectroscopy, and optical tweezers to monitor a variety of changes during the germination of single Bacillus cereus spores in both nutrient (l-alanine) and non-nutrient (Ca-dipicolinic acid (DPA)) germinants with a temporal resolution of approximately 2 s. Phase contrast microscopy assesses changes in refractility of individual spores during germination, while Raman spectroscopy gives information on changes in spore-specific molecules. The results obtained include (1) the brightness of the phase contrast image of an individual dormant spore is proportional to the level of CaDPA in that spore; (2) the end of the first Stage of germination, revealed as the end of the rapid drop in spore refractility by phase contrast microscopy, precisely corresponds to the completion of the release of CaDPA as revealed by Raman spectroscopy; and (3) the correspondence between the rapid drop in spore refractility and complete CaDPA release was observed not only for spores germinating in the well-controlled environment of an optical trap but also for spores germinating when adhered on a microscope coverslip. Using this latter method, we also simultaneously characterized the distribution of the time-to-complete-CaDPA release (T(release)) of hundreds of individual B. cereus spores germinating with both saturating and subsaturating concentrations of l-alanine and with CaDPA.

  2. Role of YpeB in Cortex Hydrolysis during Germination of Bacillus anthracis Spores

    Science.gov (United States)

    Bernhards, Casey B.

    2014-01-01

    The infectious agent of the disease anthrax is the spore of Bacillus anthracis. Bacterial spores are extremely resistant to environmental stresses, which greatly hinders spore decontamination efforts. The spore cortex, a thick layer of modified peptidoglycan, contributes to spore dormancy and resistance by maintaining the low water content of the spore core. The cortex is degraded by germination-specific lytic enzymes (GSLEs) during spore germination, rendering the cells vulnerable to common disinfection techniques. This study investigates the relationship between SleB, a GSLE in B. anthracis, and YpeB, a protein necessary for SleB stability and function. The results indicate that ΔsleB and ΔypeB spores exhibit similar germination phenotypes and that the two proteins have a strict codependency for their incorporation into the dormant spore. In the absence of its partner protein, SleB or YpeB is proteolytically degraded soon after expression during sporulation, rather than escaping the developing spore. The three PepSY domains of YpeB were examined for their roles in the interaction with SleB. YpeB truncation mutants illustrate the necessity of a region beyond the first PepSY domain for SleB stability. Furthermore, site-directed mutagenesis of highly conserved residues within the PepSY domains resulted in germination defects corresponding to reduced levels of both SleB and YpeB in the mutant spores. These results identify residues involved in the stability of both proteins and reiterate their codependent relationship. It is hoped that the study of GSLEs and interacting proteins will lead to the use of GSLEs as targets for efficient activation of spore germination and facilitation of spore cleanup. PMID:25022853

  3. Role of YpeB in cortex hydrolysis during germination of Bacillus anthracis spores.

    Science.gov (United States)

    Bernhards, Casey B; Popham, David L

    2014-10-01

    The infectious agent of the disease anthrax is the spore of Bacillus anthracis. Bacterial spores are extremely resistant to environmental stresses, which greatly hinders spore decontamination efforts. The spore cortex, a thick layer of modified peptidoglycan, contributes to spore dormancy and resistance by maintaining the low water content of the spore core. The cortex is degraded by germination-specific lytic enzymes (GSLEs) during spore germination, rendering the cells vulnerable to common disinfection techniques. This study investigates the relationship between SleB, a GSLE in B. anthracis, and YpeB, a protein necessary for SleB stability and function. The results indicate that ΔsleB and ΔypeB spores exhibit similar germination phenotypes and that the two proteins have a strict codependency for their incorporation into the dormant spore. In the absence of its partner protein, SleB or YpeB is proteolytically degraded soon after expression during sporulation, rather than escaping the developing spore. The three PepSY domains of YpeB were examined for their roles in the interaction with SleB. YpeB truncation mutants illustrate the necessity of a region beyond the first PepSY domain for SleB stability. Furthermore, site-directed mutagenesis of highly conserved residues within the PepSY domains resulted in germination defects corresponding to reduced levels of both SleB and YpeB in the mutant spores. These results identify residues involved in the stability of both proteins and reiterate their codependent relationship. It is hoped that the study of GSLEs and interacting proteins will lead to the use of GSLEs as targets for efficient activation of spore germination and facilitation of spore cleanup.

  4. Carbon-13 (13C) labeling of Bacillus subtilis vegetative cells and spores: suitability for DNA stable isotope probing (DNA-SIP) of spores in soils.

    Science.gov (United States)

    Nicholson, Wayne L; Fedenko, Jeffrey; Schuerger, Andrew C

    2009-07-01

    To test the suitability of DNA stable isotope probing (DNA-SIP) for characterizing bacterial spore populations in soils, the properties of Bacillus subtilis cells and spores intensely labeled with [(13)C]glucose were characterized. Spore germination, vegetative growth rates, and sporulation efficiency were indistinguishable on glucose versus [(13)C]glucose, as were spore wet heat and UV resistance. Unlabeled and (13)C-labeled spores contained 1.0989 and 74.336 at.% (13)C, and exhibited wet densities of 1.356 and 1.365 g/ml, respectively. Chromosomal DNAs containing (12)C versus (13)C were readily separated by their different buoyant densities in cesium chloride/ethidium bromide gradients.

  5. Decontamination of Aspergillus flavus and Aspergillus parasiticus spores on hazelnuts via atmospheric pressure fluidized bed plasma reactor.

    Science.gov (United States)

    Dasan, Beyhan Gunaydin; Mutlu, Mehmet; Boyaci, Ismail Hakki

    2016-01-04

    In this study, an atmospheric pressure fluidized bed plasma (APFBP) system was designed and its decontamination effect on aflatoxigenic fungi (Aspergillus flavus and Aspergillus parasiticus) on the surface of hazelnuts was investigated. Hazelnuts were artificially contaminated with A. flavus and A. parasiticus and then were treated with dry air plasma for up to 5min in the APFBP system at various plasma parameters. Significant reductions of 4.50 log (cfu/g) in A. flavus and 4.19 log (cfu/g) in A. parasiticus were achieved after 5min treatments at 100% V - 25kHz (655W) by using dry air as the plasma forming gas. The decontamination effect of APFBP on A. flavus and A. parasiticus spores inoculated on hazelnuts was increased with the applied reference voltage and the frequency. No change or slight reductions were observed in A. flavus and A. parasiticus load during the storage of plasma treated hazelnuts whereas on the control samples fungi continued to grow under storage conditions (30days at 25°C). Temperature change on hazelnut surfaces in the range between 35 and 90°C was monitored with a thermal camera, and it was demonstrated that the temperature increase taking place during plasma treatment did not have a lethal effect on A. flavus and A. parasiticus spores. The damage caused by APFBP treatment on Aspergillus spp. spores was also observed by scanning electron microscopy.

  6. Forensic application of microbiological culture analysis to identify mail intentionally contaminated with Bacillus anthracis spores.

    Science.gov (United States)

    Beecher, Douglas J

    2006-08-01

    The discovery of a letter intentionally filled with dried Bacillus anthracis spores in the office of a United States senator prompted the collection and quarantine of all mail in congressional buildings. This mail was subsequently searched for additional intentionally contaminated letters. A microbiological sampling strategy was used to locate heavy contamination within the 642 separate plastic bags containing the mail. Swab sampling identified 20 bags for manual and visual examination. Air sampling within the 20 bags indicated that one bag was orders of magnitude more contaminated than all the others. This bag contained a letter addressed to Senator Patrick Leahy that had been loaded with dried B. anthracis spores. Microbiological sampling of compartmentalized batches of mail proved to be efficient and relatively safe. Efficiency was increased by inoculating culture media in the hot zone rather than transferring swab samples to a laboratory for inoculation. All mail sampling was complete within 4 days with minimal contamination of the sampling environment or personnel. However, physically handling the intentionally contaminated letter proved to be exceptionally hazardous, as did sorting of cross-contaminated mail, which resulted in generation of hazardous aerosol and extensive contamination of protective clothing. Nearly 8 x 10(6) CFU was removed from the most highly cross-contaminated piece of mail found. Tracking data indicated that this and other heavily contaminated envelopes had been processed through the same mail sorting equipment as, and within 1 s of, two intentionally contaminated letters.

  7. Response of Bacillus subtilis spores to dehydration and UV irradiation at extremely low temperatures.

    Science.gov (United States)

    Dose, K; Klein, A

    1996-02-01

    Spores of Bacillus subtilis have been exposed to the conditions of extreme dehydration (argon/silica gel; simulated space vacuum) for up to 12 weeks at 298 K and 80 K in the dark. The inactivation has been correlated with the production of DNA-double strand-breaks. The temperature-dependence of the rate constants for inactivation or production of DNA-double strand-breaks is surprisingly low. Controls kept in the frozen state at 250 K for the same period of time showed no sign of deterioration. In another series of experiments the spores have been UV irradiated (253.7 nm) at 298 K, 200 K and 80 K after exposure to dehydrating conditions for 3 days. Fluence-effect relationships for inactivation, production of DNA-double strand-breaks and DNA-protein cross-links are presented. The corresponding F37-values for inactivation and production of DNA lesions are significantly increased only at 80 K (factor of 4 to 5). The data indicate that the low temperatures that prevail in the outer parts of the Solar System or at the nightside of Mars or the Moon are not sufficiently low to crucially inhibit inactivation by dehydration. Our data place further constraints on the panspermia hypothesis.

  8. Enhancing Growth of Vigna radiata in the Presence of Pseudomonas aeruginosa Biopolymer and Metarhizium anisopliae Spores

    Directory of Open Access Journals (Sweden)

    Bhagwan N. Rekadwad

    2016-01-01

    Full Text Available Exopolysaccharide producing Pseudomonas aeruginosa NCIM 2945 (PANCL belonging to gamma-proteobacterium and entomopathogenic fungus Metarhizium anisopliae MCC 1129 (MAMCC belonging to Ascomycota were studied for their morphological features biochemical characteristics and plant growth promotion ability. Optimum growth of PANCL was recorded after 24 h at temperature 30°C and pH 7.0. Gram-negative PANCL appeared as white in color, one mm size, circular, opaque, and nonconsistent elevated colonies with entire margin. It has utilized dextrose, fructose, maltose, and sorbitol as carbon source and produced acid in the medium. PANCL was sensitive to Polymyxin B (300 µgm/disc followed by Neomycin (30 µgm/disc, Gentamycin (10 µgm/disc, and Chloramphenicol (30 µgm/disc. PANCL has secreted extracellular lipase, amylase, protease, and exopolysaccharides (EPS. Another fungal strain MAMCC sporulated after 168 h at temperature 30°C and pH 7.0. MAMCC has septate-white mycelium and bears dirty green colored spores. Growth of MAMCC was enhanced in the presence of Neem and Karela-Amla oil (0.1 mL each. Extracellular polysaccharide produced by PANCL and spores of MAMCC promoted growth of dicotyledon Vigna radiata (Mung individually as well as in consortium. Considerable increase in dry weight of Vigna radiata was recorded. Thus, reported PANCL and MAMCC strains have promoted growth Vigna radiata and may be a solution for sustainable agriculture.

  9. Dipicolinic Acid Release by Germinating Clostridium difficile Spores Occurs through a Mechanosensing Mechanism

    Science.gov (United States)

    Francis, Michael B.

    2016-01-01

    ABSTRACT Classically, dormant endospores are defined by their resistance properties, particularly their resistance to heat. Much of the heat resistance is due to the large amount of dipicolinic acid (DPA) stored within the spore core. During spore germination, DPA is released and allows for rehydration of the otherwise-dehydrated core. In Bacillus subtilis, 7 proteins are encoded by the spoVA operon and are important for DPA release. These proteins receive a signal from the activated germinant receptor and release DPA. This DPA activates the cortex lytic enzyme CwlJ, and cortex degradation begins. In Clostridium difficile, spore germination is initiated in response to certain bile acids and amino acids. These bile acids interact with the CspC germinant receptor, which then transfers the signal to the CspB protease. Activated CspB cleaves the cortex lytic enzyme, pro-SleC, to its active form. Subsequently, DPA is released from the core. C. difficile encodes orthologues of spoVAC, spoVAD, and spoVAE. Of these, the B. subtilis SpoVAC protein was shown to be capable of mechanosensing. Because cortex degradation precedes DPA release during C. difficile spore germination (opposite of what occurs in B. subtilis), we hypothesized that cortex degradation would relieve the osmotic constraints placed on the inner spore membrane and permit DPA release. Here, we assayed germination in the presence of osmolytes, and we found that they can delay DPA release from germinating C. difficile spores while still permitting cortex degradation. Together, our results suggest that DPA release during C. difficile spore germination occurs though a mechanosensing mechanism. IMPORTANCE Clostridium difficile is transmitted between hosts in the form of a dormant spore, and germination by C. difficile spores is required to initiate infection, because the toxins that are necessary for disease are not deposited on the spore form. Importantly, the C. difficile spore germination pathway

  10. Sterilization of hydrogen peroxide resistant bacterial spores with stabilized chlorine dioxide.

    Science.gov (United States)

    Friedline, Anthony; Zachariah, Malcolm; Middaugh, Amy; Heiser, Matt; Khanna, Neeraj; Vaishampayan, Parag; Rice, Charles V

    2015-01-01

    Bacillus pumilus SAFR-032 spores isolated from a clean room environment are known to exhibit enhanced resistance to peroxide, desiccation, UV radiation and chemical disinfection than other spore-forming bacteria. The survival of B. pumilus SAFR-032 spores to standard clean room sterilization practices requires development of more stringent disinfection agents. Here, we report the effects of a stabilized chlorine dioxide-based biocidal agent against spores of B. pumilus SAFR-032 and Bacillus subtilis ATCC 6051. Viability was determined via CFU measurement after exposure. Chlorine dioxide demonstrated efficacy towards sterilization of spores of B. pumilus SAFR-032 equivalent or better than exposure to hydrogen peroxide. These results indicate efficacy of chlorine dioxide delivered through a stabilized chlorine dioxide product as a means of sterilization of peroxide- and UV-resistant spores.

  11. Bacterial spores as particulate carriers for gene gun delivery of plasmid DNA.

    Science.gov (United States)

    Aps, Luana R M M; Tavares, Milene B; Rozenfeld, Julio H K; Lamy, M Teresa; Ferreira, Luís C S; Diniz, Mariana O

    2016-06-20

    Bacillus subtilis spores represent a suitable platform for the adsorption of proteins, enzymes and viral particles at physiological conditions. In the present work, we demonstrate that purified spores can also adsorb DNA on their surface after treatment with cationic molecules. In addition, we demonstrate that DNA-coated B. subtilis spores can be used as particulate carriers and act as an alternative to gold microparticles for the biolistic (gene gun) administration of plasmid DNA in mice. Gene gun delivery of spores pre-treated with DODAB (dioctadecyldimethylammonium bromide) allowed efficient plasmid DNA absorption and induced protein expression levels similar to those obtained with gold microparticles. More importantly, we demonstrated that a DNA vaccine adsorbed on spores can be loaded into biolistic cartridges and efficiently delivered into mice, which induced specific cellular and antibody responses. Altogether, these data indicate that B. subtilis spores represent a simple and low cost alternative for the in vivo delivery of DNA vaccines by the gene gun technology.

  12. Comparative evaluation of eleven commercial DNA extraction kits for real-time PCR detection of Bacillus anthracis spores in spiked dairy samples.

    Science.gov (United States)

    Mertens, Katja; Freund, Lisa; Schmoock, Gernot; Hänsel, Christoph; Melzer, Falk; Elschner, Mandy C

    2014-01-17

    Spores of Bacillus anthracis are highly resistant and can survive conditions used for food preservation. Sample size and complexity represent the major hurdles for pathogen detection in food-related settings. Eleven commercial DNA extraction kits were evaluated for detection of B. anthracis spores by quantitative real-time PCR (qPCR) in dairy products. DNA was extracted from serial dilutions of B. anthracis spores in milk powder, cream cheese, whole milk and buttermilk. Three kits (QIAamp DNA mini kit, Invisorb Food kit I and II) were determined to produce the lowest limit of detections (LODs) with equally good performance. These kits employed lysozyme and proteinase K treatments or proteinase K in combination with cethyltrimethylamonium bromide-mediated (CTAB) precipitation of cell debris for cell disruption and DNA release. The LODs for these three kits were determined as 10(2) spores/ml of distilled water, 10(3)s pores/20 mg of powdered milk and 10(4) spores/100 mg of cream cheese, respectively. Performance testing of the QIAamp DNA mini kit demonstrated a good reproducibility and appropriate detection limits from 10(3)/ml for butter milk, 10(4)/ml for whole milk and 10(4)/100 mg for low fat cream cheese. However, DNA extraction efficiency was strongly inhibited by cream cheese with higher fat contents with an increased LOD of 10(6)/100 mg spores. This study demonstrated that qPCR detection depends directly on the appropriate DNA extraction method for an individual food matrix and bacterial agent.

  13. Induced sporicidal activity of chlorhexidine against Clostridium difficile spores under altered physical and chemical conditions.

    Directory of Open Access Journals (Sweden)

    Michelle M Nerandzic

    Full Text Available Chlorhexidine is a broad-spectrum antimicrobial commonly used to disinfect the skin of patients to reduce the risk of healthcare-associated infections. Because chlorhexidine is not sporicidal, it is not anticipated that it would have an impact on skin contamination with Clostridium difficile, the most important cause of healthcare-associated diarrhea. However, although chlorhexidine is not sporicidal as it is used in healthcare settings, it has been reported to kill spores of Bacillus species under altered physical and chemical conditions that disrupt the spore's protective barriers (e.g., heat, ultrasonication, alcohol, or elevated pH. Here, we tested the hypothesis that similarly altered physical and chemical conditions result in enhanced sporicidal activity of chlorhexidine against C. difficile spores.C. difficile spores became susceptible to heat killing at 80 °C within 15 minutes in the presence of chlorhexidine, as opposed to spores suspended in water which remained viable. The extent to which the spores were reduced was directly proportional to the concentration of chlorhexidine in solution, with no viable spores recovered after 15 minutes of incubation in 0.04%-0.0004% w/v chlorhexidine solutions at 80 °C. Reduction of spores exposed to 4% w/v chlorhexidine solutions at moderate temperatures (37 °C and 55 °C was enhanced by the presence of 70% ethanol. However, complete elimination of spores was not achieved until 3 hours of incubation at 55 °C. Elevating the pH to ≥9.5 significantly enhanced the killing of spores in either aqueous or alcoholic chlorhexidine solutions.Physical and chemical conditions that alter the protective barriers of C. difficile spores convey sporicidal activity to chlorhexidine. Further studies are necessary to identify additional agents that may allow chlorhexidine to reach its target within the spore.

  14. The occurrence of Ganoderma spores in the air and its relationships with meteorological factors

    Directory of Open Access Journals (Sweden)

    Agnieszka Grinn-Gofroń

    2012-12-01

    Full Text Available According to a recent study, Ganoderma may be the third genus, after Alternaria and Cladosporium, whose spores cause symptoms of allergy and whose levels are directly related to meteorological factors. There are only few articles from different parts of the world about the relationships between Ganoderma spore count and meteorological factors. The aim of the study was to review all available publications about airborne Ganoderma spores and to compare the results in a short useful form.

  15. Diurnal variations of airborne fungal spores concentration in the town and rural area

    Directory of Open Access Journals (Sweden)

    Idalia Kasprzyk

    2012-12-01

    Full Text Available Airborne fungal spores were monitored in 2001-2002 in Rzeszów (town and its neighborhood. The aim of investigations was to ascertain if there were differences in diurnal variations of airborne fungal spores concentration between town and rural area. The sampling was carried out using volumetric method. Traps were located at the same heights - app. 12 m. Airborne spores were sampled continuously. Microscopical slides were prepared for each day. Analysis was carried out on one longitudinal band of 48 mm long divided into 24 segments corresponding following hours of day. The results were expressed as mean number of fungal spores per cubic meter per 24 hours. For this survey, five geni of allergenic fungi were selected: Alternaria, Botrytis, Cladosporium, Epicoccum, Ganoderma. The concentrations of their airborne spores were high or very high. It was calculated theoretical day, where the hourly count was the percentage mean of number of spores at that time every chosen day without rainfall from 2001 and 2001 years. The diurnal periodicity of Alternaria, Cladosporium, Epicoccum and Ganoderma showed one peak, while Botrytis two. Anamorphic spores peaked in the afternoon, while their minima occurred in the morning. The highest concentrations of Ganoderma basidiospores were at down or at night, but minima during the day. There were no clear differences in the peak values between two studied sites. The results indicate that maximum concentrations of all spores generally occurred a few hour earlier in the rural area than in the town. Probably, in the rural area airborne spores came from many local sources and their diurnal periodicity reflected rhythm of spore liberation. Towns are characterized by specific microclimate with higher temperature and wind blowing to the centre. In Rzeszów fungal spores could be transported outside and carried out by wind from distant sources. This study showed, among others, that habitat conditions are an important factors

  16. Ultraweak luminescence from germinating resting spores of Entomophthora virulenta Hall et Dunn

    OpenAIRE

    Janusz Sławiński; Irena Majchrowicz; Edward Grabikowski

    2014-01-01

    Germinating resting spores of Entomophthora virulenta Hall et Dunn emit ultraweak luminescence with the intensity of the order 100 photons • s-1 • cm-2 in the spectral region 200-750 nm. The emission kinetics and intensity depend on vitality and incubation temperature of the spores. The higher the ability of resting spores to germinate, the more intense the luminescence. Elevation of the incubation temperature to 50°C enhances ultraweak luminescence. The activation energy was found to be abou...

  17. A novel method for standardized application of fungal spore coatings for mosquito exposure bioassays

    Directory of Open Access Journals (Sweden)

    Knols Bart GJ

    2010-01-01

    Full Text Available Abstract Background Interest in the use of fungal entomopathogens against malaria vectors is growing. Fungal spores infect insects via the cuticle and can be applied directly on the insect to evaluate infectivity. For flying insects such as mosquitoes, however, application of fungal suspensions on resting surfaces is more realistic and representative of field settings. For this type of exposure, it is essential to apply specific amounts of fungal spores homogeneously over a surface for testing the effects of fungal dose and exposure time. Contemporary methods such as spraying or brushing spore suspensions onto substrates do not produce the uniformity and consistency that standardized laboratory assays require. Two novel fungus application methods using equipment developed in the paint industry are presented and compared. Methods Wired, stainless steel K-bars were tested and optimized for coating fungal spore suspensions onto paper substrates. Different solvents and substrates were evaluated. Two types of coating techniques were compared, i.e. manual and automated coating. A standardized bioassay set-up was designed for testing coated spores against malaria mosquitoes. Results K-bar coating provided consistent applications of spore layers onto paper substrates. Viscous Ondina oil formulations were not suitable and significantly reduced spore infectivity. Evaporative Shellsol T solvent dried quickly and resulted in high spore infectivity to mosquitoes. Smooth proofing papers were the most effective substrate and showed higher infectivity than cardboard substrates. Manually and mechanically applied spore coatings showed similar and reproducible effects on mosquito survival. The standardized mosquito exposure bioassay was effective and consistent in measuring effects of fungal dose and exposure time. Conclusions K-bar coating is a simple and consistent method for applying fungal spore suspensions onto paper substrates and can produce coating layers

  18. Novel Strategies for Enhanced Removal of Persistent Bacillus anthracis Surrogates and Clostridium difficile Spores from Skin

    Science.gov (United States)

    Nerandzic, Michelle M.; Rackaityte, Elze; Jury, Lucy A.; Eckart, Kevin; Donskey, Curtis J.

    2013-01-01

    Background Removing spores of Clostridium difficile and Bacillus anthracis from skin is challenging because they are resistant to commonly used antimicrobials and soap and water washing provides only modest efficacy. We hypothesized that hygiene interventions incorporating a sporicidal electrochemically generated hypochlorous acid solution (Vashe®) would reduce the burden of spores on skin. Methods Hands of volunteers were inoculated with non-toxigenic C. difficile spores or B. anthracis spore surrogates to assess the effectiveness of Vashe solution for reducing spores on skin. Reduction in spores was compared for Vashe hygiene interventions versus soap and water (control). To determine the effectiveness of Vashe solution for removal of C. difficile spores from the skin of patients with C. difficile infection (CDI), reductions in levels of spores on skin were compared for soap and water versus Vashe bed baths. Results Spore removal from hands was enhanced with Vashe soak (>2.5 log10 reduction) versus soap and water wash or soak (~2.0 log10 reduction; P soap and water wash followed by soaking in Vashe removed >3.5 log10 spores from hands (P washing or soaking alone). Bed baths using soap and water (N =26 patients) did not reduce the percentage of positive skin cultures for CDI patients (64% before versus 57% after bathing; P =0.5), whereas bathing with Vashe solution (N =21 patients) significantly reduced skin contamination (54% before versus 8% after bathing; P =0.0001). Vashe was well-tolerated with no evidence of adverse effects on skin. Conclusions Vashe was safe and effective for reducing the burden of B. anthracis surrogates and C. difficile spores on hands. Bed baths with Vashe were effective for reducing C. difficile on skin. These findings suggest a novel strategy to reduce the burden of spores on skin. PMID:23844234

  19. Neutron flow exposure as a test for survival of Artemia salina spores.

    Science.gov (United States)

    Matveeva, I S; Smirnov, A N; Vodennikov, B D; Popov, I M; Semenov, D S; Kolesnikov, M V; Syroeshkin, A V

    2004-11-01

    Live and heat-inactivated Artemia salina spores (samples with the same mass and filling density) were exposed to a flow of thermal neutrons from a (252)Cf radioactive source at an equivalent dose power of about 1 microSv/h. Irradiation led to a 4-fold acceleration of nauplius development and to modification of the element profiles of live spores. The difference between absorption/diffusion of thermal neutrons by live and dead spores was revealed.

  20. Novel strategies for enhanced removal of persistent Bacillus anthracis surrogates and Clostridium difficile spores from skin.

    Science.gov (United States)

    Nerandzic, Michelle M; Rackaityte, Elze; Jury, Lucy A; Eckart, Kevin; Donskey, Curtis J

    2013-01-01

    Removing spores of Clostridium difficile and Bacillus anthracis from skin is challenging because they are resistant to commonly used antimicrobials and soap and water washing provides only modest efficacy. We hypothesized that hygiene interventions incorporating a sporicidal electrochemically generated hypochlorous acid solution (Vashe(®)) would reduce the burden of spores on skin. Hands of volunteers were inoculated with non-toxigenic C. difficile spores or B. anthracis spore surrogates to assess the effectiveness of Vashe solution for reducing spores on skin. Reduction in spores was compared for Vashe hygiene interventions versus soap and water (control). To determine the effectiveness of Vashe solution for removal of C. difficile spores from the skin of patients with C. difficile infection (CDI), reductions in levels of spores on skin were compared for soap and water versus Vashe bed baths. Spore removal from hands was enhanced with Vashe soak (>2.5 log10 reduction) versus soap and water wash or soak (~2.0 log10 reduction; Psoap and water wash followed by soaking in Vashe removed >3.5 log10 spores from hands (Psoap and water (N =26 patients) did not reduce the percentage of positive skin cultures for CDI patients (64% before versus 57% after bathing; P =0.5), whereas bathing with Vashe solution (N =21 patients) significantly reduced skin contamination (54% before versus 8% after bathing; P =0.0001). Vashe was well-tolerated with no evidence of adverse effects on skin. Vashe was safe and effective for reducing the burden of B. anthracis surrogates and C. difficile spores on hands. Bed baths with Vashe were effective for reducing C. difficile on skin. These findings suggest a novel strategy to reduce the burden of spores on skin.

  1. Novel strategies for enhanced removal of persistent Bacillus anthracis surrogates and Clostridium difficile spores from skin.

    Directory of Open Access Journals (Sweden)

    Michelle M Nerandzic

    Full Text Available BACKGROUND: Removing spores of Clostridium difficile and Bacillus anthracis from skin is challenging because they are resistant to commonly used antimicrobials and soap and water washing provides only modest efficacy. We hypothesized that hygiene interventions incorporating a sporicidal electrochemically generated hypochlorous acid solution (Vashe(® would reduce the burden of spores on skin. METHODS: Hands of volunteers were inoculated with non-toxigenic C. difficile spores or B. anthracis spore surrogates to assess the effectiveness of Vashe solution for reducing spores on skin. Reduction in spores was compared for Vashe hygiene interventions versus soap and water (control. To determine the effectiveness of Vashe solution for removal of C. difficile spores from the skin of patients with C. difficile infection (CDI, reductions in levels of spores on skin were compared for soap and water versus Vashe bed baths. RESULTS: Spore removal from hands was enhanced with Vashe soak (>2.5 log10 reduction versus soap and water wash or soak (~2.0 log10 reduction; P3.5 log10 spores from hands (P<0.01 compared to washing or soaking alone. Bed baths using soap and water (N =26 patients did not reduce the percentage of positive skin cultures for CDI patients (64% before versus 57% after bathing; P =0.5, whereas bathing with Vashe solution (N =21 patients significantly reduced skin contamination (54% before versus 8% after bathing; P =0.0001. Vashe was well-tolerated with no evidence of adverse effects on skin. CONCLUSIONS: Vashe was safe and effective for reducing the burden of B. anthracis surrogates and C. difficile spores on hands. Bed baths with Vashe were effective for reducing C. difficile on skin. These findings suggest a novel strategy to reduce the burden of spores on skin.

  2. MICROFILTRATION AND ULTRAFILTRATION OF Bacillus thuringiensis FERMENTATION BROTH: MEMBRANE PERFORMANCE AND SPORE-CRYSTAL RECOVERY APPROACHES

    OpenAIRE

    R. Marzban; F. Saberi; M.M.A. Shirazi

    2016-01-01

    Abstract Recovery of spores and crystals from the fermentation broth of Bacillus thuringiensis (Bt) was studied using the membrane separation technology. Four types of polymeric membranes, with different characteristics, in the range of microfiltration (MF) and ultrafiltration (UF) were used for evaluating their permeate flux and spore-crystal recovery capacity. Results indicated that both MF and UF membranes are effective for spore-crystal recovery. The hydrophobic MF membrane made of polyvi...

  3. Simple detection of Bacillus anthracis spores by precipitation method with goat antibody anti anthrosa

    OpenAIRE

    2016-01-01

    Background: Bacillus anthracis has a potential for biological weapon or bioterorism. Attack of Bacillus anthracis is very fatal, and the distribution is very easy and cheap through the spores. The aim of this was study to detect the spores of Bacillus anthracis. Methods: Bacillus anthracis isolates were grown on serum agar and then sheep blood medium, to stimulate capsule formation. Spores which formed painted using the method of Schaefer and Fultton. The methods of precipitation and immun...

  4. Achieving Consistent Multiple Daily Low-Dose Bacillus anthracis Spore Inhalation Exposures in the Rabbit Model

    Science.gov (United States)

    2012-06-13

    daily low-dose Bacillus anthracis spore inhalation exposures in the rabbit model Roy E. Barnewall 1, Jason E. Comer 1, Brian D. Miller 1, BradfordW...multiple exposure days. Keywords: Bacillus anthracis , inhalation exposures, low-dose, subchronic exposures, spores, anthrax, aerosol system INTRODUCTION... Bacillus Anthracis Spore Inhalation Exposures In The Rabbit Model 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d

  5. Maximum shields: the assembly and function of the bacterial spore coat.

    Science.gov (United States)

    Driks, Adam

    2002-06-01

    Spores produced by bacilli and clostridia are surrounded by a multilayered protein shell called the coat. As the armor-like appearance of the coat suggests, this structure, along with others within the spore, confers the remarkable resistance properties that make Bacillus anthracis spores such potent biological weapons. Here, I review recent studies of coat assembly in the model organism Bacillus subtilis, and explore the implications of these findings for coat assembly in B. anthracis and for defense against biological weapons.

  6. Regulation of the Spore Cortex Lytic Enzyme SleB in Bacillus anthracis

    OpenAIRE

    2014-01-01

    Bacillus anthracis is the causative agent of the disease anthrax and poses a threat due to its potential to be used as a biological weapon. The spore form of this bacterium is an extremely resistant structure, making spore decontamination exceptionally challenging. During spore germination, nutrient germinants interact with Ger receptors, triggering a cascade of events. A crucial event in this process is degradation of the cortex peptidoglycan by germination-specific lytic enzymes (GSLEs),...

  7. Current Physical and SDS Extraction Methods Do Not Efficiently Remove Exosporium Proteins from Bacillus anthracis spores

    OpenAIRE

    Thompson, Brian M.; Binkley, Jana M; Stewart, George C.

    2011-01-01

    Biochemical studies of the outermost spore layers of the Bacillus cereus family are hindered by difficulties in efficient dispersal of the external spore layers and difficulties in dissociating protein complexes that comprise the exosporium layer. Detergent and physical methods have been utilized to disrupt the exosporium layer. Herein we compare commonly used SDS extraction buffers used to extract spore proteins and demonstrate the incomplete extractability of the exosporium layer by these m...

  8. Challenges and advances in systems biology analysis of Bacillus spore physiology; molecular differences between an extreme heat resistant spore forming Bacillus subtilis food isolate and a laboratory strain.

    Science.gov (United States)

    Brul, Stanley; van Beilen, Johan; Caspers, Martien; O'Brien, Andrea; de Koster, Chris; Oomes, Suus; Smelt, Jan; Kort, Remco; Ter Beek, Alex

    2011-04-01

    Bacterial spore formers are prime organisms of concern in the food industry. Spores from the genus Bacillus are extremely stress resistant, most notably exemplified by high thermotolerance. This sometimes allows surviving spores to germinate and grow out to vegetative cells causing food spoilage and possible intoxication. Similar issues though more pending toward spore toxigenicity are observed for the anaerobic Clostridia. The paper indicates the nature of stress resistance and highlights contemporary molecular approaches to analyze the mechanistic basis of it in Bacilli. A molecular comparison between a laboratory strain and a food borne isolate, very similar at the genomic level to the laboratory strain but generating extremely heat resistant spores, is discussed. The approaches cover genome-wide genotyping, proteomics and genome-wide expression analyses studies. The analyses aim at gathering sufficient molecular information to be able to put together an initial framework for dynamic modelling of spore germination and outgrowth behaviour. Such emerging models should be developed both at the population and at the single spore level. Tools and challenges in achieving the latter are succinctly discussed.

  9. High avidity binding of engineered papaya mosaic virus virus-like particles to resting spores of Plasmodiophora brassicae.

    Science.gov (United States)

    Morin, Hélène; Tremblay, Marie-Hélène; Plante, Edith; Paré, Christine; Majeau, Nathalie; Hogue, Richard; Leclerc, Denis

    2007-02-01

    Papaya mosaic virus (PapMV) like particles (VLPs) were used as a platform for fusion of affinity peptides binding to resting spores of Plasmodiophora brassicae-a major pathogen of crucifers. Three peptides with specific affinity to the target were isolated and cloned at the C-terminus of the PapMV coat protein (CP), generating three different high avidity VLPs. The peptides were exposed at the surface of the VLPs and their avidity to resting spores of P. brassicae was measured by flow cytometry. NLP-A, with the peptide DPAPRPR, showed the highest avidity. The binding avidity of NLP-A to P. brassicae spores was comparable to that of a polyclonal antibody. NLP-A was also shown to be more specific than the antibody. Fusion of the affinity peptide to a monomeric form (mCP) of the CP [Lecours, K., Tremblay, M.-H., Laliberté Gagné, M.-E., Gagné, S.M., Leclerc, D., 2006. Purification and biochemical characterization of a monomeric form of papaya mosaic potexvirus coat protein. Protein Express. Purific. 47, 273-280] generated a fusion protein that was unable to assemble into VLPs, and mCP-A fusions failed to bind resting spores. The avidity of VLP-A was increased by adding a glycine spacer between the C-terminus of the PapMV CP and the peptide, and improved even further by using a duplicated A peptide in the fusion protein. The use of high avidity VLPs has advantages over polyclonal antibodies because of target specificity. VLPs offers the specificity of monoclonal antibodies but can be more easily generated using the powerful selection of phage display.

  10. Delayed Clostridium perfringens growth from a spore inocula by sodium lactate in sous-vide chicken products.

    Science.gov (United States)

    Juneja, Vijay K

    2006-04-01

    Clostridium perfringens growth from a spore inoculum was investigated in vacuum-packaged, cook-in-bag marinated chicken breast that included 0%, 1.5%, 3%, or 4.8% sodium lactate (NaL; w/w). The packages were processed to an internal temperature of 71.1 degrees C, ice chilled and stored at 4, 19, and 25 degrees C. The total C. perfringens population was determined by plating diluted samples on Tryptose-sulfite-cycloserine agar followed by anaerobic incubation for 48 h at 37 degrees C. At 25 degrees C, addition of 1.5% NaL was effective in delaying growth for 29 h. Increasing the NaL level to 4.8%, C. perfringens growth from a spore inoculum during storage at 25 degrees C for 480 h was not observed. At 19 degrees C, the growth was > 6 log 10 cfu/g by 288 h in control samples. In samples with 3.0% or 4.8% NaL, the growth of C. perfringens from spores was dramatically restricted with little or no growth in 648 h at 19 degrees C. C. perfringens growth was not observed at 4 degrees C regardless of NaL concentration. The D-values at 55 degrees C ranged from 47.40 (no NaL) to 57.58 min (1.5% NaL). Cyclic and static temperature abuse of refrigerated products for 20 h did not permit C. perfringens growth. However, temperature abuse of products for periods 24 h or longer in the absence of NaL led to growth of C. perfringens from a spore inoculum. An extra degree of safety may be assured in such products by supplementation with NaL at 1.5-4.8% NaL level.

  11. Detection limit of Clostridium botulinum spores in dried mushroom samples sourced from China.

    Science.gov (United States)

    Malakar, Pradeep K; Plowman, June; Aldus, Clare F; Xing, Zengtao; Zhao, Yong; Peck, Michael W

    2013-08-16

    A survey of dried mushrooms (Lentinula edodes (Shiitake) and Auricularia auricula (Wood Ear)) sourced from China was carried out to determine the natural contamination of these mushrooms with spores of proteolytic Clostridium botulinum and non-proteolytic C. botulinum. The mushrooms were collected from supermarkets and retailers in 21 cities in China during October 2008. Spore loads of C. botulinum in mushrooms have a degree of uncertainty and variability and this study contributes valuable data for determining prevalence of spores of C. botulinum in mushrooms. An optimized detection protocol that combined selective enrichment culture with multiplex PCR was used to test for spores of proteolytic and non-proteolytic C. botulinum. Detection limits were calculated, using a maximum likelihood protocol, from mushroom samples inoculated with defined numbers of spores of proteolytic C. botulinum or non-proteolytic C. botulinum. Based on the maximum likelihood detection limit, it is estimated that dried mushroom A. auricula contained <550spores/kg of proteolytic C. botulinum, and <350spores/kg of non-proteolytic C. botulinum. Dried L. edodes contained <1500spores/kg of proteolytic C. botulinum and it was not possible to determine reliable detection limits for spores of non-proteolytic C. botulinum using the current detection protocol.

  12. Fungal spore content of the atmosphere of the Cave of Nerja (southern Spain): diversity and origin.

    Science.gov (United States)

    Docampo, Silvia; Trigo, M Mar; Recio, Marta; Melgar, Marta; García-Sánchez, José; Cabezudo, Baltasar

    2011-01-15

    Fungal spores are of great interest in aerobiology and allergy due to their high incidence in both outdoor and indoor environments and their widely recognized ability to cause respiratory diseases and other pathologies. In this work, we study the spore content of the atmosphere of the Cave of Nerja, a karstic cavity and an important tourist attraction situated on the eastern coast of Malaga (southern Spain), which receives more than half a million visitors every year. This study was carried out over an uninterrupted period of 4 years (2002-2005) with the aid of two Hirst-type volumetric pollen traps (Lanzoni VPPS 2000) situated in different halls of the cave. In the atmosphere of the Cave of Nerja, 72 different spore types were detected during the studied period and daily mean concentrations of up to 282,195 spores/m(3) were reached. Thirty-five of the spore types detected are included within Ascomycota and Basidiomycota (19 and 16 types, respectively). Of the remaining spore types, 32 were categorized within the group of so-called imperfect fungi, while Oomycota and Myxomycota were represented by 2 and 3 spore types, respectively. Aspergillus/Penicillium was the most abundant spore type with a yearly mean percentage that represented 50% of the total, followed by Cladosporium. Finally, the origin of the fungal spores found inside the cave is discussed on the basis of the indoor/outdoor concentrations and the seasonal behaviour observed. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Rapid inactivation of Penicillium digitatum spores using high-density nonequilibrium atmospheric pressure plasma

    Science.gov (United States)

    Iseki, Sachiko; Ohta, Takayuki; Aomatsu, Akiyoshi; Ito, Masafumi; Kano, Hiroyuki; Higashijima, Yasuhiro; Hori, Masaru

    2010-04-01

    A promising, environmentally safe method for inactivating fungal spores of Penicillium digitatum, a difficult-to-inactivate food spoilage microorganism, was developed using a high-density nonequilibrium atmospheric pressure plasma (NEAPP). The NEAPP employing Ar gas had a high electron density on the order of 1015 cm-3. The spores were successfully and rapidly inactivated using the NEAPP, with a decimal reduction time in spores (D value) of 1.7 min. The contributions of ozone and UV radiation on the inactivation of the spores were evaluated and concluded to be not dominant, which was fundamentally different from the conventional sterilizations.

  14. Decontamination of B. globigii spores from drinking water infrastructure using disinfectants

    Data.gov (United States)

    U.S. Environmental Protection Agency — Decontamination of Bacillus spores adhered to common drinking water infrastructure surfaces was evaluated using a variety of disinfectants. Corroded iron and...

  15. Metabolism of bile salts in mice influences spore germination in Clostridium difficile.

    Directory of Open Access Journals (Sweden)

    Jennifer L Giel

    Full Text Available Clostridium difficile, a spore-forming bacterium, causes antibiotic-associated diarrhea. In order to produce toxins and cause disease, C. difficile spores must germinate and grow out as vegetative cells in the host. Although a few compounds capable of germinating C. difficile spores in vitro have been identified, the in vivo signal(s to which the spores respond were not previously known. Examination of intestinal and cecal extracts from untreated and antibiotic-treated mice revealed that extracts from the antibiotic-treated mice can stimulate colony formation from spores to greater levels. Treatment of these extracts with cholestyramine, a bile salt binding resin, severely decreased the ability of the extracts to stimulate colony formation from spores. This result, along with the facts that the germination factor is small, heat-stable, and water-soluble, support the idea that bile salts stimulate germination of C. difficile spores in vivo. All extracts able to stimulate high level of colony formation from spores had a higher proportion of primary to secondary bile salts than extracts that could not. In addition, cecal flora from antibiotic-treated mice was less able to modify the germinant taurocholate relative to flora from untreated mice, indicating that the population of bile salt modifying bacteria differed between the two groups. Taken together, these data suggest that an in vivo-produced compound, likely bile salts, stimulates colony formation from C. difficile spores and that levels of this compound are influenced by the commensal gastrointestinal flora.

  16. Evaluation of germination, distribution, and persistence of Bacillus subtilis spores through the gastrointestinal tract of chickens.

    Science.gov (United States)

    Latorre, J D; Hernandez-Velasco, X; Kallapura, G; Menconi, A; Pumford, N R; Morgan, M J; Layton, S L; Bielke, L R; Hargis, B M; Téllez, G

    2014-07-01

    Spores are popular as direct-fed microbials, though little is known about their mode of action. Hence, the first objective of the present study was to evaluate the in vitro germination and growth rate of Bacillus subtilis spores. Approximately 90% of B. subtilis spores germinate within 60 min in the presence of feed in vitro. The second objective was to determine the distribution of these spores throughout different anatomical segments of the gastrointestinal tract (GIT) in a chicken model. For in vivo evaluation of persistence and dissemination, spores were administered to day-of-hatch broiler chicks either as a single gavage dose or constantly in the feed. During 2 independent experiments, chicks were housed in isolation chambers and fed sterile corn-soy-based diets. In these experiments one group of chickens was supplemented with 10(6) spores/g of feed, whereas a second group was gavaged with a single dose of 10(6) spores per chick on day of hatch. In both experiments, crop, ileum, and cecae were sampled from 5 chicks at 24, 48, 72, 96, and 120 h. Viable B. subtilis spores were determined by plate count method after heat treatment (75°C for 10 min). The number of recovered spores was constant through 120 h in each of the enteric regions from chickens receiving spores supplemented in the feed. However, the number of recovered B. subtilis spores was consistently about 10(5) spores per gram of digesta, which is about a 1-log10 reduction of the feed inclusion rate, suggesting approximately a 90% germination rate in the GIT when fed. On the other hand, recovered B. subtilis spores from chicks that received a single gavage dose decreased with time, with only approximately 10(2) spores per gram of sample by 120 h. This confirms that B. subtilis spores are transiently present in the GIT of chickens, but the persistence of vegetative cells is presently unknown. For persistent benefit, continuous administration of effective B. subtilis direct-fed microbials as vegetative

  17. Live/Dead Bacterial Spore Assay Using DPA-Triggered Tb Luminescence

    Science.gov (United States)

    Ponce, Adrian

    2003-01-01

    A method of measuring the fraction of bacterial spores in a sample that remain viable exploits DPA-triggered luminescence of Tb(3+) and is based partly on the same principles as those described earlier. Unlike prior methods for performing such live/dead assays of bacterial spores, this method does not involve counting colonies formed by cultivation (which can take days), or counting of spores under a microscope, and works whether or not bacterial spores are attached to other small particles (i.e., dust), and can be implemented on a time scale of about 20 minutes.

  18. Utility of sodium hypochlorite for ultrastructure study of bacterial spore integuments.

    Science.gov (United States)

    Rode, L J; Williams, M G

    1966-12-01

    Rode, L. J. (The University of Texas, Austin), and M. Glenn Williams. Utility of sodium hypochlorite for ultrastructure study of bacterial spore integuments. J. Bacteriol. 92:1772-1778. 1966.-Spores of Bacillus megaterium are partially dissolved by sodium hypochlorite. Spore integuments become visible during the dissolution, and ultrastructural features may be detected. Three distinct integument types are described for B. megaterium QM B1551 with the use of this technique. Since a variety of microbial cells are affected by sodium hypochlorite, its use may be applicable to ultrastructure study of cells other than bacterial spores.

  19. In pursuit of protein targets: proteomic characterization of bacterial spore outer layers.

    Science.gov (United States)

    Abhyankar, Wishwas; Hossain, Abeer H; Djajasaputra, André; Permpoonpattana, Patima; Ter Beek, Alexander; Dekker, Henk L; Cutting, Simon M; Brul, Stanley; de Koning, Leo J; de Koster, Chris G

    2013-10-04

    Bacillus cereus, responsible for food poisoning, and Clostridium difficile, the causative agent of Clostridium difficile-associated diarrhea (CDAD), are both spore-forming pathogens involved in food spoilage, food intoxication, and other infections in humans and animals. The proteinaceous coat and the exosporium layers from spores are important for their resistance and pathogenicity characteristics. The exosporium additionally provides an ability to adhere to surfaces eventually leading to spore survival in food. Thus, studying these layers and identifying suitable protein targets for rapid detection and removal of spores is of the utmost importance. In this study, we identified 100 proteins from B. cereus spore coat, exosporium and 54 proteins from the C. difficile coat insoluble protein fraction. In an attempt to define a universal set of spore outer layer proteins, we identified 11 superfamily domains common to the identified proteins from two Bacilli and one Clostridium species. The evaluated orthologue relationships of identified proteins across different spore formers resulted in a set of 13 coat proteins conserved across the spore formers and 12 exosporium proteins conserved in the B. cereus group, which could be tested for quick and easy detection or targeted in strategies aimed at removal of spores from surfaces.

  20. Current Physical and SDS Extraction Methods Do Not Efficiently Remove Exosporium Proteins from Bacillus anthracis spores

    Science.gov (United States)

    Thompson, Brian M.; Binkley, Jana M.; Stewart, George C.

    2011-01-01

    Biochemical studies of the outermost spore layers of the Bacillus cereus family are hindered by difficulties in efficient dispersal of the external spore layers and difficulties in dissociating protein complexes that comprise the exosporium layer. Detergent and physical methods have been utilized to disrupt the exosporium layer. Herein we compare commonly used SDS extraction buffers used to extract spore proteins and demonstrate the incomplete extractability of the exosporium layer by these methods. Sonication and bead beating methods for exosporium layer removal were also examined. A combination of genetic and physical methods is the most effective for isolating proteins found in the spore exosporium. PMID:21338631

  1. Effects of meteorological factors on the levels of Alternaria spores on a potato crop

    Science.gov (United States)

    Escuredo, Olga; Seijo, Maria Carmen; Fernández-González, Maria; Iglesias, Isabel

    2011-03-01

    Alternaria solani Soraeur produces early blight in Solanum tuberosum L., leading to significant agricultural losses. The current study was carried out on the extensive potato crop situated in north-western of Spain during 2007, 2008 and 2009. In this area potato crops are the most important source of income. In this work we used a Hirst-type volumetric spore-trap for the aerobiological monitoring of Alternaria spores. The highest spore concentrations were recorded during the 2009 cycle (10,555 spores), and the lowest concentrations were recorded during the 2008 cycle (5,471 spores). Over the 3 years of study, the highest concentrations were registered during the last stage of the crop. The aim of the study was to observe the influence of meteorological factors on the concentration of Alternaria spores, which can lead to serious infection and early blight. Prediction of the stages during which a crop is particularly vulnerable to infection allows for adjustment of the application of fungicide and is of environmental and agricultural importance. For this reason, we tested three models (P-Days, DD and IWP) to predict the first treatment and decrease the negative effect that these spores have on potato crops. The parameter that showed the most significant correlation with spore concentrations was minimum temperature. We used ARIMA (autoregressive integrated model of running mean) time-series models to determine the forecast. We considered weather data as predictor variables and the concentration of spores on the previous day as the fixed variable.

  2. At-line determination of spore inoculum quality in Penicillium chrysogenum bioprocesses.

    Science.gov (United States)

    Ehgartner, Daniela; Herwig, Christoph; Neutsch, Lukas

    2016-06-01

    Spore inoculum quality in filamentous bioprocesses is a critical parameter influencing pellet morphology and, consequently, process performance. It is essential to determine the concentration of viable spores before inoculation, to implement quality control and decrease batch-to-batch variability. The ability to assess the spore physiologic status with close-to-real time resolution would offer interesting perspectives enhanced process analytical technology (PAT) and quality by design (QbD) strategies. Up to now, the parameters contributing to spore inoculum quality are not clearly defined. The state-of-the-art method to investigate this variable is colony-forming unit (CFU) determination, which assesses the number of growing spores. This procedure is tedious, associated with significant inherent bias, and not applicable in real time.Here, a novel method is presented, based on the combination of viability staining (propidium iodide and fluorescein diacetate) and large-particle flow cytometry. It is compatible with the complex medium background often observed in filamentous bioprocesses and allows for a classification of the spores into different subpopulations. Next to viable spores with intact growth potential, dormant or inactive as well as physiologically compromised cells are accurately determined. Hence, a more holistic few on spore inoculum quality and early-phase biomass composition is provided, offering enhanced information content.In an industrially relevant model bioprocess, good correlation to CFU counts was found. Morphological parameters (e.g. spore swelling) that are not accessible via standard monitoring tools were followed over the initial process phase with close temporal resolution.

  3. Current physical and SDS extraction methods do not efficiently remove exosporium proteins from Bacillus anthracis spores.

    Science.gov (United States)

    Thompson, Brian M; Binkley, Jana M; Stewart, George C

    2011-05-01

    Biochemical studies of the outermost spore layers of the Bacillus cereus family are hindered by difficulties in efficient dispersal of the external spore layers and difficulties in dissociating protein complexes that comprise the exosporium layer. Detergent and physical methods have been utilized to disrupt the exosporium layer. Herein we compare commonly used SDS extraction buffers used to extract spore proteins and demonstrate the incomplete extractability of the exosporium layer by these methods. Sonication and bead beating methods for exosporium layer removal were also examined. A combination of genetic and physical methods is the most effective for isolating proteins found in the spore exosporium.

  4. An improved system for the surface immobilisation of proteins on Bacillus thuringiensis vegetative cells and spores through a new spore cortex-lytic enzyme anchor.

    Science.gov (United States)

    Shao, Xiaohu; Ni, Hong; Lu, Ting; Jiang, Mengtian; Li, Hua; Huang, Xinfeng; Li, Lin

    2012-02-15

    An improved surface-immobilisation system was engineered to target heterologous proteins onto vegetative cells and spores of Bacillus thuringiensis plasmid-free recipient strain BMB171. The sporulation-dependent spore cortex-lytic enzyme from B. thuringiensis YBT-1520, SceA, was expressed in vegetative cells and used as the surface anchoring motif. Green fluorescent protein (GFP) and a Bacillus endo-β-1,3-1,4-glucanase (BglS) were used as the fusion partners to test the binding efficiency and the functional activities of immobilised surface proteins. The surface localisation of the SceA-GFP fusion protein on vegetative cells and spores was confirmed by Western blot, immunofluorescence microscopy and flow cytometry. The GFP fluorescence intensity from both vegetative cells and spores was measured and compared to a previously characterised surface display system using a peptidoglycan hydrolase anchor (Mbg). Results demonstrated comparable efficiency of SceA- and Mbg-mediated immobilisation on vegetative cells but a more efficient immobilisation on spores using the SceA anchor, suggesting SceA has greater potential for spore-based applications. The SceA protein was then applied to target BglS onto vegetative cells and spores, and the surface immobilisation was verified by the substantial whole-cell enzymatic activity and enhanced whole-spore enzymatic activity compared to vegetative cells. A dually active B. thuringiensis vegetative cell and spore display system could prove especially valuable for the development of regenerable and heat-stable biocatalysts that function under adverse environmental conditions, for example, an effective feed additive for improved digestion and nutrient absorption by livestock.

  5. Characteristics and determinants of ambient fungal spores in Hualien, Taiwan

    Science.gov (United States)

    Ho, Hsiao-Man; Rao, Carol Y.; Hsu, Hsiao-Hsien; Chiu, Yueh-Hsiu; Liu, Chi-Ming; Chao, H. Jasmine

    Characteristics and determinants of ambient aeroallergens are of much concern in recent years because of the apparent health impacts of allergens. Yet relatively little is known about the complex behaviors of ambient aeroallergens. To address this issue, we monitored ambient fungal spores in Hualien, Taiwan from 1993-1996 to examine the compositions and temporal variations of fungi, and to evaluate possible determinants. We used a Burkard seven-day volumetric spore trap to collect daily fungal spores. Air pollutants, meteorological factors, and Asian dust events were included in the statistical analyses to predict fungal levels. We found that the most dominant fungal categories were ascospores, followed by Cladosporium and Aspergillus/Penicillium. The majority of the fungal categories had significant diurnal and seasonal variations. Total fungi, Cladosporium, Ganoderma, Arthrinium/Papularia, Cercospora, Periconia, Alternaria, Botrytis, and PM 10 had significantly higher concentrations ( p<0.05) during the period affected by Asian dust events. In multiple regression models, we found that temperature was consistently and positively associated with fungal concentrations. Other factors correlated with fungal concentrations included ozone, particulate matters with an aerodynamic diameter less than 10 μm (PM 10), relative humidity, rainfall, atmospheric pressure, total hydrocarbons, carbon monoxide, nitrogen dioxide, and sulfur dioxide. Most of the fungal categories had higher levels in 1994 than in 1995-96, probably due to urbanization of the study area. In this study, we demonstrated complicated interrelationships between fungi and air pollution/meteorological factors. In addition, long-range transport of air pollutants contributed significantly to local aeroallergen levels. Future studies should examine the health impacts of aeroallergens, as well as the synergistic/antagonistic effects of weather, and local and global-scale air pollutions.

  6. Hydrolysis of cortex peptidoglycan during bacterial spore germination.

    Science.gov (United States)

    Makino, Shio; Moriyama, Ryuichi

    2002-06-01

    Despite the most extreme dormancy and resistance properties among living systems, bacterial endospores retain an alert sensory mechanism to respond to the germinants and initiate germination. Although the molecular mechanism of the germination process is not completely described, current progress in the studies on the enzymes involved in the process gave us a somewhat clearer picture of the process of spore peptidoglycan (cortex) hydrolysis, a major biochemical event in germination. Germination-specific cortex-lytic enzymes require muramic acid d-lactam in their substrates. At least two types of enzymes are involved in the germination process: a spore cortex-lytic enzyme (SCLE) and a cortical fragment-lytic enzyme (CFLE). Except for their peptidoglycan-binding regions, the primary structures of SCLE and CFLE vary according species. Both enzymes differ in their hydrolytic bond-specificities and recognition of the substrates morphology. SCLE appears to initiate germination by uncrosslinking the intract cortex, and the CFLE further degrades the polysaccharide moiety of the SCLE-modified cortex. In vivo CFLE activity is likely regulated by its requirement for partially un-crosslinked cortex, while SCLE requires activation process. Clostridium perfringens SCLE is activated by a germination-specific serine protease during germination, but the activation mechanism of SCLE in Bacillus species is unknown. Cortex-lytic enzymes are expressed at the early stage of sporulation but the compartment of expression depends on proteins. However, all enzymes are located outside the cortex layer in dormant spores, suggesting that the hydrolysis process initiates at the exterior side of the cortex. The assembly of the germination apparatus is also discussed.

  7. Dry heat exposures of surface exposed and embedded Bacillus spores

    Science.gov (United States)

    Schubert, Wayne

    Dry heat microbial reduction (DHMR) is the primary technique used to reduce the microbial load of spacecraft and component parts. Often, manufacturing procedures require heating flight hardware to high temperatures for purposes other than planetary protection DHMR. The existing specifications, however, do not allow for additional planetary protection bioburden reduction credit if the hardware is exposed without controlled relative humidity. The intent of this study was to provide adequate data on the DHMR technique to support modification of four aspects of current requirements; expansion of acceptable time and temperature combinations used for spacecraft dry heat microbial reduction processes above 125° C, determining the effect that humidity has on spore lethality as a function of temperature, understanding the lethality for spores with exceptionally high thermal resistance and to investigate the extended exposure requirement for materials that might contain embedded microorganisms. Spores from two bacterial species were tested, B. atrophaeus ATCC 9372 and B. sp. ATCC 29669, under three conditions encompassing 5 temperature points. Embedded experiments utilized a silicone rubber polymer that is commonly used on robotic spacecraft, and surface exposed experiments were performed under both ambient and vacuum-controlled humidity conditions. The results obtained support the use of DHMR protocols that extend the maximum temperature range from 125° C to 170° C, with either controlled or ambient humidity. If implemented, this will give projects bioburden reduction credit for shorter treatments at extended temperatures, and allow spacecraft to be processed in more readily available and less expensive facilities that do not have humidity control, with significant cost and schedule benefits. The study also demonstrated that the required heating time for materials presumed to have embedded bioburden is conservative.

  8. Episodic perturbations of end-Permian atmosphere recorded in plant spore chemistry

    Science.gov (United States)

    Fraser, Wesley; Lomax, Barry; Beerling, David; James, David; Pyle, John; Self, Stephen; Sephton, Mark; Wellman, Charles

    2016-04-01

    The largest marine Phanerozoic extinction occurred 251 million years ago at the end of the Permian period with a contemporaneous major reorganisation of terrestrial. Previous work suggests the eruption of the Siberian Traps large igneous province could have generated substantial volumes of ozone depleting substances; the result being a partial collapse of the stratospheric ozone layer, and commensurate increase in ultraviolet-B (UV-B, 280-315nm) radiation. Increased UV-B flux would contribute additional pressures to an already stressed environment and flora and fauna. Here we present data utilising a new biogeochemical proxy for UV-B radiation to analyse clubmoss (lycophyta) megaspores to track UV-B radiation across the end-Permian interval. Our biogeochemical data when combined with published work on spore and pollen mutations suggests a highly dynamic global atmospheric system, oscillating between episodes of high and low UV-B flux, most likely driven by pulsed eruptive phases of the Siberian Traps.

  9. Bacterial spores survive treatment with commercial sterilants and disinfectants.

    Science.gov (United States)

    Sagripanti, J L; Bonifacino, A

    1999-09-01

    This study compared the activity of commercial liquid sterilants and disinfectants on Bacillus subtilis spores deposited on three types of devices made of noncorrodible, corrodible, or polymeric material. Products like Renalin, Exspor, Wavicide-01, Cidexplus, and cupric ascorbate were tested under conditions specified for liquid sterilization. These products, at the shorter times indicated for disinfection, and popular disinfectants, like Clorox, Cavicide, and Lysol were also studied. Data obtained with a sensitive and quantitative test suggest that commercial liquid sterilants and disinfectants are less effective on contaminated surfaces than generally acknowledged.

  10. Encapsulation of Bacterial Spores in Nanoorganized Polyelectrolyte Shells (Postprint)

    Science.gov (United States)

    2009-05-27

    Baca, H.; Ashley, C.; Carnes , E.; Lopez, D.; Flemming, J.; Dunphy, D.; Singh, S.; Lopez, G.; Brozik, S.; Werner-Washburne, M.; Brinker, J. Science...concentration of aqueous polyelectrolytes was 2 mg/mL ( pH 6.8). All polymer samples were treated briefly in a sonicating bath and then vortex mixed before...positively charged and PGA is negatively charged at pH 6.5-7 due to amine and acid ionized Scheme 1 Figure 1. ζ-potential of a B. subtilis spore in DI water at

  11. An Optical Biosensor for Bacillus Cereus Spore Detection

    Science.gov (United States)

    Li, Chengquan; Tom, Harry W. K.

    2005-03-01

    We demonstrate a new transduction scheme for optical biosensing. Bacillus cereus is a pathogen that may be found in food and dairy products and is able to produce toxins and cause food poisoning. It is related to Bacillus anthracis (anthrax). A CCD array covered with micro-structured glass coverslip is used to detect the optical resonant shift due to the binding of the antigen (bacillus cereus spore) to the antibody (polyclonal antibody). This novel optical biosensor scheme has the potential for detecting 10˜100 bioagents in a single device as well as the potential to test for antigens with multiple antibody tests to avoid ``false positives.''

  12. Spore production of Beauveria bassiana from agro-industrial residues

    Directory of Open Access Journals (Sweden)

    Herta Stutz Dalla Santa

    2005-06-01

    Full Text Available The purpose of this work was to produce Beauveria bassiana by Solid-State Fermentation using agro-industrial residues and optimizing the cultivation conditions. Refused potatoes, coffee husks and sugar-cane bagasse were tested. The blend of refused potatoes and sugar-cane bagasse (60-40% with particle size in the range of 0.8-2 mm was used in the fermentation experiments. In Erlenmeyer flasks the best spore production was achieved with the following conditions: incubation temperature 26º C; initial pH 6.0; inoculum concentration 10(7 spores.g-1.dw and initial moisture 75%. In the column type reactor using forced aeration under the optimized conditions, the maximum production (1.07x10(10spores.g-1.dw was obtained at the 10th day of fermentation. The respirometric analyses of the fermentation showed a strong correlation between fungal growth and spore production.O objetivo deste trabalho foi produzir Beauveria bassiana por fermentação no estado sólido em resíduos agro-industriais e otimizar as condições de cultivo. Batata-refugo, polpa de café e bagaço de cana de açúcar foram testados. A mistura de batata-refugo e de bagaço de cana de açúcar (60:40%, com granulometria de 2 a 0,8 mm foi escolhida como melhor substrato/suporte. Em frascos de Erlenmeyer a produção de esporos foi maior com as seguintes condições: pH 6,0; temperatura de incubação de 26º C; taxa de inóculo de 10(7 esporos.g-1 de matéria seca; e umidade inicial de 75%. Em bioreator do tipo coluna com aeração forçada, as condições otimizadas possibilitaram uma produção máxima de esporos no 10º dia de fermentação, obtendo-se 1,07x10(10 esporos.g-1 de matéria seca. A análise respirométrica desta fermentação permitiu correlacionar o desenvolvimento do fungo com a produção de esporos.

  13. Deoxyribonucleic acid synthesis and deoxynucleotide metabolism during bacterial spore germination.

    Science.gov (United States)

    Setlow, P

    1973-06-01

    Deoxyribonucleic acid (DNA) synthesis during germination of Bacillus megaterium spores takes place in two stages. In stage I (0-55 min) DNA synthesis is slow and there is no detectable net synthesis, whereas in stage II (from 55 min on) the rate of synthesis is much faster and net DNA synthesis occurs. Deoxyribonucleotide pool sizes match the rates of DNA synthesis in stages I and II. The level of deoxyribonucleotide triphosphates is not correlated with the level of deoxyribonucleotide kinases, but rather with that of ribonucleotide reductase activity.

  14. Comparison of the antitumor activity on spore polysaccharides (G/-SP) and broken spore polysaccharides (Gl-BSP) isolated from Ganoderma lucidum

    Institute of Scientific and Technical Information of China (English)

    Peng-yunWANG; Zhi-binLIN

    2004-01-01

    AIM: To compare the antitumor activity of spore polysaccharides (GI-SP) and broken spore polysaccharides (GI-BSP) from spores of Ganoderma lucidum (Leyss ex fr) Karst. METHODS: BALB/c mice were implanted with Sarcoma 180 and administered intragastrically with Gl-SP or G/-BPS (50, 100, 200 mg/kg)respectively for 14 d. At the end of experiment, the tumor were removed and weighted. At the same time, spleens of tumorbearing mice were prepared to observe the effect of Gl-SP and

  15. Ice nucleation by fungal spores from the classes Agaricomycetes, Ustilaginomycetes, and Eurotiomycetes, and the effect on the atmospheric transport of these spores

    Science.gov (United States)

    Haga, D. I.; Burrows, S. M.; Iannone, R.; Wheeler, M. J.; Mason, R. H.; Chen, J.; Polishchuk, E. A.; Pöschl, U.; Bertram, A. K.

    2014-08-01

    We studied the ice nucleation properties of 12 different species of fungal spores chosen from three classes: Agaricomycetes, Ustilaginomycetes, and Eurotiomycetes. Agaricomycetes include many types of mushroom species and are widely distributed over the globe. Ustilaginomycetes are agricultural pathogens and have caused widespread damage to crops. Eurotiomycetes are found on all types of decaying material and include important human allergens. We focused on these classes because they are thought to be abundant in the atmosphere and because there is very little information on the ice nucleation ability of these classes of spores in the literature. All of the fungal spores investigated contained some fraction of spores that serve as ice nuclei at temperatures warmer than homogeneous freezing. The cumulative number of ice nuclei per spore was 0.001 at temperatures between -19 °C and -29 °C, 0.01 between -25.5 °C and -31 °C, and 0.1 between -26 °C and -31.5 °C. On average, the order of ice nucleating ability for these spores is Ustilaginomycetes > Agaricomycetes ≃ Eurotiomycetes. The freezing data also suggests that, at temperatures ranging from -20 °C to -25 °C, all of the fungal spores studied here are less efficient ice nuclei compared to Asian mineral dust on a per surface area basis. We used our new freezing results together with data in the literature to compare the freezing temperatures of spores from the phyla Basidiomycota and Ascomycota, which together make up 98% of known fungal species found on Earth. The data show that within both phyla (Ascomycota and Basidiomycota), there is a wide range of freezing properties, and also that the variation within a phylum is greater than the variation between the average freezing properties of the phyla. Using a global chemistry-climate transport model, we investigated whether ice nucleation on the studied spores, followed by precipitation, can influence the transport and global distributions of these spores in

  16. Ice Nucleation of Fungal Spores from the Classes Agaricomycetes, Ustilaginomycetes, and Eurotiomycetes, and the effect on the Atmospheric Transport of these Spores

    Energy Technology Data Exchange (ETDEWEB)

    Haga, D. I.; Burrows, Susannah M.; Iannone, R.; Wheeler, M. J.; Mason, R.; Chen, J.; Polishchuk, E. A.; Poschl, U.; Bertram, Allan K.

    2014-08-26

    Ice nucleation on fungal spores may affect the frequency and properties of ice and mixed-phase clouds. We studied the ice nucleation properties of 12 different species of fungal spores chosen from three classes: Agaricomycetes, Ustilagomycetes, and Eurotiomycetes. Agaricomycetes include many types of mushroom species and are cosmopolitan all over the globe. Ustilagomycetes are agricultural pathogens and have caused widespread damage to crops. Eurotiomycetes are found on all types of decaying material and include important human allergens. We focused on these classes since they are thought to be abundant in the atmosphere and because there is very little information on the ice nucleation ability of these classes of spores in the literature. All of the fungal spores investigated were found to cause freezing of water droplets at temperatures warmer than homogeneous freezing. The cumulative number of ice nuclei per spore was 0.001 at temperatures between -19 °C and -29 °C, 0.01 between -25.5 °C and -31 °C, and 0.1 between -26 °C and -36 °C. On average, the order of ice nucleating ability for these spores is Ustilagomycetes > Agaricomycetes ≅ Eurotiomycetes. We show that at temperatures below -20 °C, all of the fungal spores studied here are less efficient ice nuclei compared to Asian mineral dust on a per surface area basis. We used our new freezing results together with data in the literature to compare the freezing temperatures of spores from the phyla Basidiomycota and Ascomycota, which together make up 98 % of known fungal species found on Earth. The data show that within both phyla (Ascomycota and Basidiomycota) there is a wide range of freezing properties, and also that the variation within a phylum is greater than the variation between the average freezing properties of the phyla. Using a global chemistry-climate transport model, we investigated whether ice nucleation on the studied spores, followed by precipitation, can influence the atmospheric

  17. Detection and Enumeration of Spore-Forming Bacteria in Powdered Dairy Products

    Science.gov (United States)

    McHugh, Aoife J.; Feehily, Conor; Hill, Colin; Cotter, Paul D.

    2017-01-01

    With the abolition of milk quotas in the European Union in 2015, several member states including Ireland, Luxembourg, and Belgium have seen year on year bi-monthly milk deliveries to dairies increase by up to 35%. Milk production has also increased outside of Europe in the past number of years. Unsurprisingly, there has been a corresponding increased focus on the production of dried milk products for improved shelf life. These powders are used in a wide variety of products, including confectionery, infant formula, sports dietary supplements and supplements for health recovery. To ensure quality and safety standards in the dairy sector, strict controls are in place with respect to the acceptable quantity and species of microorganisms present in these products. A particular emphasis on spore-forming bacteria is necessary due to their inherent ability to survive extreme processing conditions. Traditional microbiological detection methods used in industry have limitations in terms of time, efficiency, accuracy, and sensitivity. The following review will explore the common spore-forming bacterial contaminants of milk powders, will review the guidelines with respect to the acceptable limits of these microorganisms and will provide an insight into recent advances in methods for detecting these microbes. The various advantages and limitations with respect to the application of these diagnostics approaches for dairy food will be provided. It is anticipated that the optimization and application of these methods in appropriate ways can ensure that the enhanced pressures associated with increased production will not result in any lessening of safety and quality standards. PMID:28197144

  18. Decontamination options for Bacillus anthracis-contaminated drinking water determined from spore surrogate studies.

    Science.gov (United States)

    Raber, Ellen; Burklund, Alison

    2010-10-01

    Five parameters were evaluated with surrogates of Bacillus anthracis spores to determine effective decontamination alternatives for use in a contaminated drinking water supply. The parameters were as follows: (i) type of Bacillus spore surrogate (B. thuringiensis or B. atrophaeus), (ii) spore concentration in suspension (10(2) and 10(6) spores/ml), (iii) chemical characteristics of the decontaminant (sodium dichloro-S-triazinetrione dihydrate [Dichlor], hydrogen peroxide, potassium peroxymonosulfate [Oxone], sodium hypochlorite, and VirkonS), (iv) decontaminant concentration (0.01% to 5%), and (v) exposure time to decontaminant (10 min to 1 h). Results from 138 suspension tests with appropriate controls are reported. Hydrogen peroxide at a concentration of 5% and Dichlor or sodium hypochlorite at a concentration of 2% were highly effective at spore inactivation regardless of spore type tested, spore exposure time, or spore concentration evaluated. This is the first reported study of Dichlor as an effective decontaminant for B. anthracis spore surrogates. Dichlor's desirable characteristics of high oxidation potential, high level of free chlorine, and a more neutral pH than that of other oxidizers evaluated appear to make it an excellent alternative. All three oxidizers were effective against B. atrophaeus spores in meeting the EPA biocide standard of greater than a 6-log kill after a 10-min exposure time and at lower concentrations than typically reported for biocide use. Solutions of 5% VirkonS and Oxone were less effective as decontaminants than other options evaluated in this study and did not meet the EPA's efficacy standard for a biocide, although they were found to be as effective for concentrations of 10(2) spores/ml. Differences in methods and procedures reported by other investigators make quantitative comparisons among studies difficult.

  19. The characterisation of Bacillus spores occurring in the manufacturing of (low acid) canned products.

    Science.gov (United States)

    Oomes, S J C M; van Zuijlen, A C M; Hehenkamp, J O; Witsenboer, H; van der Vossen, J M B M; Brul, S

    2007-11-30

    Spore-forming bacteria can be a problem in the food industry, especially in the canning industry. Spores present in ingredients or present in the processing environment severely challenge the preservation process since their thermal resistance may be very high. We therefore asked the question which bacterial spore formers are found in a typical soup manufacturing plant, where they originate from and what the thermal resistance of their spores is. To answer these questions molecular techniques for bacterial species and strain identification were used as well as a protocol for the assessment of spore heat stress resistance based on the Kooiman method. The data indicate the existence and physiological cause of the high thermal resistance of spores of many of the occurring species. In particular it shows that ingredients used in soup manufacturing are a rich source of high thermal resistant spores and that sporulation in the presence of ingredients rich in divalent metal ions exerts a strong influence on spore heat resistance. It was also indicated that Bacillus spores may well be able to germinate and resporulate during manufacturing i.e. through growth and sporulation in line. Both these spores and those originating from the ingredients were able to survive certain thermal processing settings. Species identity was confirmed using fatty acid analysis, 16SrRNA gene sequencing and DNA-DNA hybridisation. Finally, molecular typing experiments using Ribotyping and AFLP analysis show that strains within the various Bacillus species can be clustered according to the thermal resistance properties of their spores. AFLP performed slightly better than Ribotyping. The data proofed to be useful for the generation of strain specific probes. Protocols to validate these probes in routine identification and innovation aimed at tailor made heat processing in soup manufacturing have been formulated.

  20. Germination and outgrowth of spores of Bacillus cereus group members: diversity and role of germinant receptors.

    Science.gov (United States)

    Abee, Tjakko; Groot, Masja Nierop; Tempelaars, Marcel; Zwietering, Marcel; Moezelaar, Roy; van der Voort, Menno

    2011-04-01

    Bacillus cereus is a gram-positive, facultative anaerobic, endospore-forming toxicogenic human pathogen. Endospores are highly specialized, metabolically dormant cell types that are resistant to extreme environmental conditions, including heat, dehydration and other physical stresses. B. cereus can enter a range of environments, and can in its spore form, survive harsh conditions. If these conditions become favorable, spores can germinate and grow out and reach considerable numbers in a range of environments including processed foods. Certainly the last decade, when consumer preferences have shifted to mildly processed food, new opportunities arose for spore-forming spoilage and pathogenic organisms. Only rigorous methods have been shown to be capable of destroying all spores present in food, thus a shift toward e.g., milder heat preservation strategies, may result in low but significant amounts of viable spores in food products. Hence, the need for a mild spore destruction strategy is eminent including control of spore outgrowth. Consequently, there is a large interest in triggering spore germination in foodstuffs, since germinated spores have lost the extreme resistance of dormant spores and are relatively easy to kill. Another option could be to prevent germination so that no dangerous levels can be reached. This contribution will focus on germination and outgrowth characteristics of B. cereus and other members of the B. cereus group, providing an overview of the niches these spore-formers can occupy, the signals that trigger germination, and how B. cereus copes with these wake-up calls in different environments including foods, during food processing and upon interaction with the human host.

  1. Self-healing concrete by use of microencapsulated bacterial spores

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.Y. [Magnel Laboratory for Concrete Research, Faculty of Engineering and Architecture, Ghent University, TechnologieparkZwijnaarde 904, B-9052 Ghent (Belgium); Laboratory of Microbial Ecology and Technology (LabMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent (Belgium); Soens, H. [Devan Chemicals NV, Klein Frankrijk 18, 9600 Ronse (Belgium); Verstraete, W. [Laboratory of Microbial Ecology and Technology (LabMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent (Belgium); De Belie, N., E-mail: nele.debelie@ugent.be [Magnel Laboratory for Concrete Research, Faculty of Engineering and Architecture, Ghent University, TechnologieparkZwijnaarde 904, B-9052 Ghent (Belgium)

    2014-02-15

    Microcapsules were applied to encapsulate bacterial spores for self-healing concrete. The viability of encapsulated spores and the influence of microcapsules on mortar specimens were investigated first. Breakage of the microcapsules upon cracking was verified by Scanning Electron Microscopy. Self-healing capacity was evaluated by crack healing ratio and the water permeability. The results indicated that the healing ratio in the specimens with bio-microcapsules was higher (48%–80%) than in those without bacteria (18%–50%). The maximum crack width healed in the specimens of the bacteria series was 970 μm, about 4 times that of the non-bacteria series (max 250 μm). The overall water permeability in the bacteria series was about 10 times lower than that in non-bacteria series. Wet–dry cycles were found to stimulate self-healing in mortar specimens with encapsulated bacteria. No self-healing was observed in all specimens stored at 95%RH, indicating that the presence of liquid water is an essential component for self-healing.

  2. Holographic deep learning for rapid optical screening of anthrax spores

    Science.gov (United States)

    Jo, YoungJu; Park, Sangjin; Jung, JaeHwang; Yoon, Jonghee; Joo, Hosung; Kim, Min-hyeok; Kang, Suk-Jo; Choi, Myung Chul; Lee, Sang Yup; Park, YongKeun

    2017-01-01

    Establishing early warning systems for anthrax attacks is crucial in biodefense. Despite numerous studies for decades, the limited sensitivity of conventional biochemical methods essentially requires preprocessing steps and thus has limitations to be used in realistic settings of biological warfare. We present an optical method for rapid and label-free screening of Bacillus anthracis spores through the synergistic application of holographic microscopy and deep learning. A deep convolutional neural network is designed to classify holographic images of unlabeled living cells. After training, the network outperforms previous techniques in all accuracy measures, achieving single-spore sensitivity and subgenus specificity. The unique “representation learning” capability of deep learning enables direct training from raw images instead of manually extracted features. The method automatically recognizes key biological traits encoded in the images and exploits them as fingerprints. This remarkable learning ability makes the proposed method readily applicable to classifying various single cells in addition to B. anthracis, as demonstrated for the diagnosis of Listeria monocytogenes, without any modification. We believe that our strategy will make holographic microscopy more accessible to medical doctors and biomedical scientists for easy, rapid, and accurate point-of-care diagnosis of pathogens. PMID:28798957

  3. Efficient transformation of Rhizopus delemar by electroporation of germinated spores.

    Science.gov (United States)

    Xu, Sha; Zhou, Zhengxiong; Du, Guocheng; Zhou, Jingwen; Chen, Jian

    2014-08-01

    High efficient transformation of mycelial fungi is essential to both metabolic engineering and physiological analysis of these industrially important microorganisms. However, transformation efficiencies for mycelial fungi are highly restricted by difficulties in colony formation and competent cell preparation. In this work, an innovative transformation procedure that could significantly improve the efficiency of colony formation and transformation process has been established for a typical mycelial fungus, Rhizopus delemar. Single colonies of R. delemar were obtained with the addition of sodium deoxycholate. Fresh germinated spores of R. delemar were successfully transformed by electroporation. In addition, by pretreatment of the germinated spores with 0.05M lithium acetate (LiAc) and 20mM dithiothreitol (DTT) before electroporation, the transformation efficiency was further improved by 9.5-fold. The final transformation efficiency at optimal conditions reached 1239 transformants/μg DNA. The method described here would facilitate more efficient metabolic engineering and investigation of physiological functions in R. delemar or other similar mycelial fungi.

  4. Investigation of UV-TiO2 photocatalysis and its mechanism in Bacillus subtilis spore inactivation.

    Science.gov (United States)

    Zhang, Yiqing; Zhou, Lingling; Zhang, Yongji

    2014-09-01

    The inactivation levels of Bacillus subtilis spores for various disinfection processes (ultraviolet (UV), TiO2 and UV-TiO2) were compared. The results showed that the inactivation effect of B. subtilis spores by UV treatment alone was far below that for bacteria without endospores. TiO2 alone in the dark, as a control experiment, exhibited almost no inactivation effect. Compared with UV treatment alone, the inactivation effect increased significantly with the addition of TiO2. Increases of the UV irradiance and TiO2 concentration both contributed to the increase of the inactivation effect. Lipid peroxidation was found to be the underlying mechanism of inactivation. Malondialdehyde (MDA), the degradation product of lipid peroxidation, was used as an index to determine the extent of the reaction. The MDA concentration surged surprisingly to 3.24nmol/mg dry cell with the combination disinfection for 600sec (0.10mW/cm(2) irradiance and 10mg/L TiO2). In contrast, for UV alone or TiO2 in the dark, the MDA concentration was 0.38 and 0.25nmol/mg dry cell, respectively, under the same conditions. This indicated that both UV and TiO2 were essential for lipid peroxidation. Changes in cell ultrastructure were observed by transmission electron microscopy. The cell membrane was heavily damaged and cellular contents were completely lysed with the UV-TiO2 process, suggesting that lipid peroxidation was the root of the enhancement in inactivation efficiency.

  5. Role of visible light-activated photocatalyst on the reduction of anthrax spore-induced mortality in mice.

    Directory of Open Access Journals (Sweden)

    Jyh-Hwa Kau

    Full Text Available BACKGROUND: Photocatalysis of titanium dioxide (TiO(2 substrates is primarily induced by ultraviolet light irradiation. Anion-doped TiO(2 substrates were shown to exhibit photocatalytic activities under visible-light illumination, relative environmentally-friendly materials. Their anti-spore activity against Bacillus anthracis, however, remains to be investigated. We evaluated these visible-light activated photocatalysts on the reduction of anthrax spore-induced pathogenesis. METHODOLOGY/PRINCIPAL FINDINGS: Standard plating method was used to determine the inactivation of anthrax spore by visible light-induced photocatalysis. Mouse models were further employed to investigate the suppressive effects of the photocatalysis on anthrax toxin- and spore-mediated mortality. We found that anti-spore activities of visible light illuminated nitrogen- or carbon-doped titania thin films significantly reduced viability of anthrax spores. Even though the spore-killing efficiency is only approximately 25%, our data indicate that spores from photocatalyzed groups but not untreated groups have a less survival rate after macrophage clearance. In addition, the photocatalysis could directly inactivate lethal toxin, the major virulence factor of B. anthracis. In agreement with these results, we found that the photocatalyzed spores have tenfold less potency to induce mortality in mice. These data suggest that the photocatalysis might injury the spores through inactivating spore components. CONCLUSION/SIGNIFICANCE: Photocatalysis induced injuries of the spores might be more important than direct killing of spores to reduce pathogenicity in the host.

  6. Hourly predictive artificial neural network and multivariate regression tree models of Alternaria and Cladosporium spore concentrations in Szczecin (Poland)

    Science.gov (United States)

    Grinn-Gofroń, Agnieszka; Strzelczak, Agnieszka

    2009-11-01

    A study was made of the link between time of day, weather variables and the hourly content of certain fungal spores in the atmosphere of the city of Szczecin, Poland, in 2004-2007. Sampling was carried out with a Lanzoni 7-day-recording spore trap. The spores analysed belonged to the taxa Alternaria and Cladosporium. These spores were selected both for their allergenic capacity and for their high level presence in the atmosphere, particularly during summer. Spearman correlation coefficients between spore concentrations, meteorological parameters and time of day showed different indices depending on the taxon being analysed. Relative humidity (RH), air temperature, air pressure and clouds most strongly and significantly influenced the concentration of Alternaria spores. Cladosporium spores correlated less strongly and significantly than Alternaria. Multivariate regression tree analysis revealed that, at air pressures lower than 1,011 hPa the concentration of Alternaria spores was low. Under higher air pressure spore concentrations were higher, particularly when RH was lower than 36.5%. In the case of Cladosporium, under higher air pressure (>1,008 hPa), the spores analysed were more abundant, particularly after 0330 hours. In artificial neural networks, RH, air pressure and air temperature were the most important variables in the model for Alternaria spore concentration. For Cladosporium, clouds, time of day, air pressure, wind speed and dew point temperature were highly significant factors influencing spore concentration. The maximum abundance of Cladosporium spores in air fell between 1200 and 1700 hours.

  7. Pyrimidine dimer formation and germination of UV-irradiated spores of Dictyostelium discoideum NC-4 and. gamma. s-13

    Energy Technology Data Exchange (ETDEWEB)

    Nozu, K.; Ohnishi, T.; Okaichi, K. (Nara Medical Univ., Kashihara (Japan))

    1982-04-01

    Survival, UV-photoproducts and germination of UV-irradiated spores of Dictyostelium discoideum were studied on two strains, NC-4 and ..gamma..s-13. The spores of NC-4 are about 35 times more resistant to UV than ..gamma..s-13 spores at 10% survival. Pyrimidine dimers were formed in UV-irradiated spores in both strains. No photoproducts other than pyrimidine dimers were detected. The formation of pyrimidine dimers in spores was about 2% in both strains at 800 J/m/sup 2/. In the germination of spores, the conversion of spores into swollen spores was not affected by UV in both strains, but the emergence of amoebae from the swollen spores was suppressed, which was more distinctive in ..gamma..s-13 spores than in NC-4 spores. The emerged amoebae from the UV-irradiated NC-4 spores were viable, while those from the ..gamma..s-13 spores were inviable even when they succeeded in emergence.

  8. Toward a Noninvasive, Label-Free Screening Method for Determining Spore Inoculum Quality of Penicillium chrysogenum Using Raman Spectroscopy.

    Science.gov (United States)

    Wieland, Karin; Kuligowski, Julia; Ehgartner, Daniela; Ramer, Georg; Koch, Cosima; Ofner, Johannes; Herwig, Christoph; Lendl, Bernhard

    2017-01-01

    We report on a label-free, noninvasive method for determination of spore inoculum quality of Penicillium chrysogenum prior to cultivation/germination. Raman microspectroscopy providing direct, molecule-specific information was used to extract information on the viability state of spores sampled directly from the spore inoculum. Based on the recorded Raman spectra, a supervised classification method was established for classification between living and dead spores and thus determining spore inoculum quality for optimized process control. A fast and simple sample preparation method consisting of one single dilution step was employed to eliminate interfering signals from the matrix and to achieve isolation of single spores on the sample carrier (CaF2). Aiming to avoid any influence of the killing procedure in the Raman spectrum of the spore, spores were considered naturally dead after more than one year of storage time. Fluorescence staining was used as reference method. A partial least squares discriminant analysis classifier was trained with Raman spectra of 258 living and dead spores (178 spectra for calibration, 80 spectra for validation). The classifier showed good performance when being applied to a 1 µL droplet taken from a 1:1 mixture of living and dead spores. Of 135 recorded spectra, 51% were assigned to living spores while 49% were identified as dead spores by the classifier. The results obtained in this work are a fundamental step towards developing an automated, label-free, and noninvasive screening method for assessing spore inoculum quality.

  9. Draft Genome Sequences of Seven Thermophilic Spore-Forming Bacteria Isolated from Foods That Produce Highly Heat-Resistant Spores, Comprising Geobacillus spp., Caldibacillus debilis, and Anoxybacillus flavithermus

    NARCIS (Netherlands)

    Berendsen, Erwin M; Wells-Bennik, Marjon H J; Krawczyk, Antonina O; de Jong, Anne; van Heel, Auke; Holsappel, Siger; Eijlander, Robyn T; Kuipers, Oscar P

    2016-01-01

    Here, we report the draft genomes of five strains of Geobacillus spp., one Caldibacillus debilis strain, and one draft genome of Anoxybacillus flavithermus, all thermophilic spore-forming Gram-positive bacteria.

  10. Draft Genome Sequences of Seven Thermophilic Spore-Forming Bacteria Isolated from Foods That Produce Highly Heat-Resistant Spores, Comprising Geobacillus spp., Caldibacillus debilis, and Anoxybacillus flavithermus

    Science.gov (United States)

    Berendsen, Erwin M.; Wells-Bennik, Marjon H. J.; Krawczyk, Antonina O.; de Jong, Anne; van Heel, Auke; Holsappel, Siger; Eijlander, Robyn T.

    2016-01-01

    Here, we report the draft genomes of five strains of Geobacillus spp., one Caldibacillus debilis strain, and one draft genome of Anoxybacillus flavithermus, all thermophilic spore-forming Gram-positive bacteria. PMID:27151781

  11. Clostridium difficile virulence factors: Insights into an anaerobic spore-forming pathogen

    Science.gov (United States)

    Awad, Milena M; Johanesen, Priscilla A; Carter, Glen P; Rose, Edward; Lyras, Dena

    2014-01-01

    The worldwide emergence of epidemic strains of Clostridium difficile linked to increased disease severity and mortality has resulted in greater research efforts toward determining the virulence factors and pathogenesis mechanisms used by this organism to cause disease. C. difficile is an opportunist pathogen that employs many factors to infect and damage the host, often with devastating consequences. This review will focus on the role of the 2 major virulence factors, toxin A (TcdA) and toxin B (TcdB), as well as the role of other putative virulence factors, such as binary toxin, in C. difficile-mediated infection. Consideration is given to the importance of spores in both the initiation of disease and disease recurrence and also to the role that surface proteins play in host interactions. PMID:25483328

  12. Effects of humidity on sterilization of Geobacillus stearothermophilus spores with plasma-excited neutral gas

    Science.gov (United States)

    Matsui, Kei; Ikenaga, Noriaki; Sakudo, Noriyuki

    2015-06-01

    We investigate the effects of relative humidity on the sterilization process using a plasma-excited neutral gas that uniformly sterilizes both the space and inner wall of the reactor chamber at atmospheric pressure. Only reactive neutral species such as plasma-excited gas molecules and radicals were separated from the plasma and sent to the reactor chamber for chemical sterilization. The plasma source gas is nitrogen mixed with 0.1% oxygen, and the relative humidity in the source gas is controlled by changing the mixing ratio of water vapor. The relative humidity near the sample in the reactor chamber is controlled by changing the sample temperature. As a result, the relative humidity near the sample should be kept in the range from 60 to 90% for the sterilization of Geobacillus stearothermophilus spores. When the relative humidity in the source gas increases from 30 to 90%, the sterilization effect is enhanced by the same degree.

  13. Bacillus subtilis spore protein SpoVAC functions as a mechanosensitive channel

    NARCIS (Netherlands)

    Velasquez Guzman, Jeanette; Schuurman-Wolters, Geesina; Birkner, Jan Peter; Abee, Tjakko; Poolman, Bert

    2014-01-01

    A critical event during spore germination is the release of Ca-DPA (calcium in complex with dipicolinic acid). The mechanism of release of Ca-DPA through the inner membrane of the spore is not clear, but proteins encoded by the Bacillus subtilis spoVA operon are involved in the process. We cloned an

  14. Evaluating the transport of bacillus subtilis spores as a potential surrogate for Cryptosporidium parvum Oocysts

    Science.gov (United States)

    The USEPA has recommended the use of aerobic spores as an indicator for Cryptosporidium oocysts when determining groundwater under the direct influence of surface water. Surface properties, interaction energies, transport, retention, and release behavior of B. subtilis spores were measured over a r...

  15. Detecting Clostridium difficile spores from inanimate surfaces of the hospital environment: which method is best?

    Science.gov (United States)

    Claro, Tânia; Daniels, Stephen; Humphreys, Hilary

    2014-09-01

    The recovery of Clostridium difficile spores from hospital surfaces was assessed using rayon swabs, flocked swabs, and contact plates. The contact plate method was less laborious, achieved higher recovery percentages, and detected spores at lower inocula than swabs. Rayon swabs were the least efficient method. However, further studies are required in health care settings.

  16. Presence of Clostridium botulinum spores in Matricaria chamomilla (chamomile) and its relationship with infant botulism.

    Science.gov (United States)

    Bianco, María I; Lúquez, Carolina; de Jong, Laura I T; Fernández, Rafael A

    2008-02-10

    Nowadays, infant botulism is the most important form of human botulism in some countries. This illness affects infants younger than 52 weeks of age. The infection occurs in the intestinal tract; therefore, ingestion of Clostridium botulinum spores with food is proposed. In some countries, people use chamomile tea as a household remedy for intestinal colics and given this tea to infants. Chamomile can be contaminated with C. botulinum and could be a vehicle of its spores. Our aim was to study the prevalence and spore-load of C. botulinum in chamomile. We analysed 200 samples; the 7.5% of them were contaminated with botulinum spores. However, prevalence of these spores was significantly higher in chamomile sold by weight in herbal stores (unwrapped chamomile) than prevalence in chamomile sold in tea bags (p=0.0055). The spore-load detected in all positive samples was 0.3-0.4 spores per gram of chamomile. We identified C. botulinum types A, B, and F in the 53.3%, 6.7%, and 13.3%, respectively. Chamomile (principally, unwrapped chamomile) is a potencial vehicle of C. botulinum spores, and ingestion of chamomile tea could represent a risk for infant botulism.

  17. High gas pressure: an innovative method for the inactivation of dried bacterial spores.

    Science.gov (United States)

    Colas de la Noue, A; Espinasse, V; Perrier-Cornet, J-M; Gervais, P

    2012-08-01

    In this article, an original non-thermal process to inactivate dehydrated bacterial spores is described. The use of gases such as nitrogen or argon as transmission media under high isostatic pressure led to an inactivation of over 2 logs CFU/g of Bacillus subtilis spores at 430 MPa, room temperature, for a 1 min treatment. A major requirement for the effectiveness of the process resided in the highly dehydrated state of the spores. Only a water activity below 0.3 led to substantial inactivation. The solubility of the gas in the lipid components of the spore and its diffusion properties was essential to inactivation. The main phenomenon involved seems to be the sorption of the gas under pressure by the spores' structures such as residual pores and plasma membranes, followed by a sudden drop in pressure. Observation by phase-contrast microscopy suggests that internal structures have been affected by the treatment. Some parallels with polymer permeability to gas and rigidity at various water activities offer a few clues about the behavior of the outer layers of spores in response to this parameter and provide a good explanation for the sensitivity of spores to high gas pressure discharge at low hydration levels. Specificity of microorganisms such as size, organization, and composition could help in understanding the differences between spores and yeast regarding the parameters required for inactivation, such as pressure or maintenance time.

  18. Specific peptides as alternative to antibody ligands for biomagnetic separation of Clostridium tyrobutyricum spores.

    Science.gov (United States)

    Lavilla, Maria; Moros, Maria; Puertas, Sara; Grazú, Valeria; Pérez, María Dolores; Calvo, Miguel; de la Fuente, Jesus M; Sánchez, Lourdes

    2012-04-01

    Nowadays, the reference method for the detection of Clostridium tyrobutyricum in milk is the most-probable-number method, a very time-consuming and non-specific method. In this work, the suitability of the use of superparamagnetic beads coated with specific antibodies and peptides for bioseparation and concentration of spores of C. tyrobutyricum has been assessed. Peptide or antibody functionalized nanoparticles were able to specifically bind C. tyrobutyricum spores and concentrate them up to detectable levels. Moreover, several factors, such as particle size (200 nm and 1 μm), particle derivatization (aminated and carboxylated beads), coating method, and type of ligand have been studied in order to establish the most appropriate conditions for spore separation. Results show that concentration of spore is favored by a smaller bead size due to the wider surface of interaction in relation to particle volume. Antibody orientation, related to the binding method, is also critical in spore recovery. However, specific peptides seem to be a better ligand than antibodies, not only due to the higher recovery ratio of spores obtained but also due to the prolonged stability over time, allowing an optimal recovery of spores up to 3 weeks after bead coating. These results demonstrate that specific peptides bound to magnetic nanoparticles can be used instead of traditional antibodies to specifically bind C. tyrobutyricum spores being a potential basis for a rapid method to detect this bacterial target.

  19. Minimizing the level of butyric acid bacteria spores in farm tank milk

    NARCIS (Netherlands)

    Vissers, M.M.M.; Driehuis, F.; Giffel, M.C.T.; Jong, de P.; Lankveld, J.M.G.

    2007-01-01

    A year-long survey of 24 dairy farms was conducted to determine the effects of farm management on the concentrations of butyric acid bacteria (BAB) spores in farm tank milk (FTM). The results were used to validate a control strategy derived from model simulations. The BAB spore concentrations were m

  20. Gas discharge plasmas are effective in inactivating Bacillus and Clostridium spores.

    Science.gov (United States)

    Tseng, Shawn; Abramzon, Nina; Jackson, James O; Lin, Wei-Jen

    2012-03-01

    Bacterial spores are the most resistant form of life and have been a major threat to public health and food safety. Nonthermal atmospheric gas discharge plasma is a novel sterilization method that leaves no chemical residue. In our study, a helium radio-frequency cold plasma jet was used to examine its sporicidal effect on selected strains of Bacillus and Clostridium. The species tested included Bacillus subtilis, Bacillus stearothermophilus, Clostridium sporogenes, Clostridium perfringens, Clostridium difficile, and Clostridium botulinum type A and type E. The plasmas were effective in inactivating selected Bacillus and Clostridia spores with D values (decimal reduction time) ranging from 2 to 8 min. Among all spores tested, C. botulinum type A and C. sporogenes were significantly more resistant to plasma inactivation than other species. Observations by phase contrast microscopy showed that B. subtilis spores were severely damaged by plasmas and the majority of the treated spores were unable to initiate the germination process. There was no detectable fragmentation of the DNA when the spores were treated for up to 20 min. The release of dipicolinic acid was observed almost immediately after the plasma treatment, indicating the spore envelope damage could occur quickly resulting in dipicolinic acid release and the reduction of spore resistance.

  1. Detection of Fungal Spores Using a Generic Surface Plasmon Resonance Immunoassay

    DEFF Research Database (Denmark)

    Skottrup, Peter; Hearty, Stephen; Frøkiær, Hanne;

    2007-01-01

    . Spiked Pst samples were further examined in a background of a related spore and it was found that Pst quantification was possible in this mixture. This study represent the first use of SPR technology for fungal spore detection as well as the first report of a successful biosensor-based detection strategy...

  2. Bringing Evolution to a Technological Generation: A Case Study with the Video Game SPORE

    Science.gov (United States)

    Poli, DorothyBelle; Berenotto, Christopher; Blankenship, Sara; Piatkowski, Bryan; Bader, Geoffrey A.; Poore, Mark

    2012-01-01

    The video game SPORE was found to hold characteristics that stimulate higher-order thinking even though it rated poorly for accurate science. Interested in evaluating whether a scientifically inaccurate video game could be used effectively, we exposed students to SPORE during an evolution course. Students that played the game reported that they…

  3. Dynamic localization of penicillin-binding proteins during spore development in Bacillus subtilis

    NARCIS (Netherlands)

    Scheffers, Dirk-Jan

    2005-01-01

    During Bacillus subtilis spore formation, many membrane proteins that function in spore development localize to the prespore septum and, subsequently, to the outer prespore membrane. Recently, it was shown that the cell-division-specific penicillin-binding proteins (PBPs) 1 and 2b localize to the as

  4. Removal of Bacillus anthracis sterne spore from commercial unpasteurized liquid egg white using crossflow microfiltration

    Science.gov (United States)

    Current pasteurization technology used by the egg industry is ineffective for destruction of spores such as those of Bacillus anthracis (BA). The validity of a cross-flow microfiltration (MF) process for separation of the attenuated strain of BA (Sterne) spores from commercial unpasteurized liquid ...

  5. The contribution of endogenous and exogenous effects to radiation-induced damage in the bacterial spore.

    Science.gov (United States)

    Jacobs, G P; Samuni, A; Czapski, G

    1985-06-01

    Radical scavengers such as polyethylene glycol 400 and 4000 and bovine albumin have been used to define the contribution of exogenous and endogenous effects to the gamma-radiation-induced damage in aqueous buffered suspensions of Bacillus pumilus spores. The results indicate that this damage in the bacterial spore is predominantly endogenous both in the presence of 1 atmosphere of oxygen, and in anoxia.

  6. The characterisation of Bacillus spores occurring in the manufacturing of (low acid) canned products

    NARCIS (Netherlands)

    Oomes, S.J.C.M.; Zuijlen, A.C.M. van; Hehenkamp, J.O.; Witsenboer, H.; Vossen, J.M.B.M. van der; Brul, S.

    2007-01-01

    Spore-forming bacteria can be a problem in the food industry, especially in the canning industry. Spores present in ingredients or present in the processing environment severely challenge the preservation process since their thermal resistance may be very high. We therefore asked the question which

  7. Contribution of endogenous and exogenous effects to radiation-induced damage in the bacterial spore

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, G.P. (Hebrew Univ., Jerusalem (Israel). School of Pharmacy); Samuni, A. (Hebrew Univ., Jerusalem (Israel). School of Medicine); Czapski, G. (Hebrew Univ., Jerusalem (Israel). Dept. of Physical Chemistry)

    1985-06-01

    Radical scavengers such as polyethylene glycol 400 and 4000 and bovine albumin have been used to define the contribution of exogenous and endogenous effects to the gamma-radiation-induced damage in aqueous buffered suspensions of Bacillus pumilus spores. The results indicate that this damage in the bacterial spore is predominantly endogenous both in the presence of 1 atmosphere of oxygen, and in anoxia.

  8. Inactivation and ultrastructure analysis of Bacillus spp. and Clostridium perfringens spores.

    Science.gov (United States)

    Brantner, Christine A; Hannah, Ryan M; Burans, James P; Pope, Robert K

    2014-02-01

    Bacterial endospores are resistant to many environmental factors from temperature extremes to ultraviolet irradiation and are generally more difficult to inactivate or kill than vegetative bacterial cells. It is often considered necessary to treat spores or samples containing spores with chemical fixative solutions for prolonged periods of time (e.g., 1-21 days) to achieve fixation/inactivation to enable electron microscopy (EM) examination outside of containment laboratories. Prolonged exposure to chemical fixatives, however, can alter the ultrastructure of spores for EM analyses. This study was undertaken to determine the minimum amount of time required to inactivate/sterilize and fix spore preparations from several bacterial species using a universal fixative solution for EM that maintains the ultrastructural integrity of the spores. We show that a solution of 4% paraformaldehyde with 1% glutaraldehyde inactivated spore preparations of Bacillus anthracis, Bacillus cereus, Bacillus megaterium, Bacillus thuringiensis, and Clostridium perfringens in 30 min, and Bacillus subtilis in 240 min. These results suggest that this fixative solution can be used to inactivate and fix spores from several major groups of bacterial spore formers after 240 min, enabling the fixed preparations to be removed from biocontainment and safely analyzed by EM outside of biocontainment.

  9. Challenges in risk assessment and predictive microbiology of foodborne spore-forming bacteria.

    Science.gov (United States)

    Augustin, Jean-Christophe

    2011-04-01

    Mathematical description of the behavior of bacterial foodborne pathogens and concepts of risk assessment were first applied to spore-forming bacteria and specially to Clostridium botulinum with numerous works dealing with spores heat destruction to ensure the safety of canned foods or with their germination and growth probability in foods. This paper discusses two aspects which appear specific to pathogenic sporeformers in comparison to vegetative microorganisms, that is, firstly, the extreme intra-species biodiversity of spore-forming bacteria and its consequences for risk assessment and, secondly, the modeling of spore germination and outgrowth processes. The intra-species biodiversity of spore-forming bacteria has a great impact on hazard identification, exposure assessment and hazard characterization leading thus to an extremely variable individual poisoning risk for consumers. The germination and outgrowth processes were shown independent at the single cell level and although numerous studies were performed to study the effect of spores treatments and growth conditions on these two events, the mathematical modeling and the prediction of these processes is still challenging today. The difficulties to accurately assess the biodiversity and the germination and outgrowth processes of spore-forming bacteria lead to a substantial uncertainty in risk estimates related to the exposure to these microorganisms. Nevertheless, significant progress have been made these last years improving the relevance of quantitative risk assessments for spore-forming bacteria and decreasing the risk uncertainty. Despite these difficulties, risk assessment still constitutes a valuable tool to justify the implementation of management options.

  10. Spore dispersal of fetid Lysurus mokusin by feces of mycophagous insects.

    Science.gov (United States)

    Chen, Gao; Zhang, Rui-Rui; Liu, Yang; Sun, Wei-Bang

    2014-08-01

    The ecological roles and biological mechanisms of zoochory in plants have long been foci in studies of co-evolutionary processes between plants and animals. However, the dispersal of fungal spores by animals has received comparatively little attention. In this study, the dispersal of spores of a selected fetid fungus, Lysurus mokusin, via feces of mycophagous insects was explored by: collecting volatiles emitted by the fungus using dynamic headspace extraction and analyzing them by GC-MS; testing the capacity of mycophagous insects to disperse its spores by counting spores in their feces; comparing the germinability of L. mokusin spores extracted from feces of nocturnal earwigs and natural gleba of the fungus; and assessing the ability of L. mokusin volatiles to attract insects in bioassays with synthetic scent mixtures. Numerous spores were detected in insects' feces, the bioassays indicated that L. mokusin odor (similar to that of decaying substances) attracts diverse generalist mycophagous insects, and passage through the gut of Anisolabis maritima earwigs significantly enhanced the germination rate of L. mokusin spores. Therefore, nocturnal earwigs and diurnal flies probably play important roles in dispersal of L. mokusin spores, and dispersal via feces may be an important common dispersal mechanism for fungal reproductive tissue.

  11. The Effect of Growth Medium on B. anthracis Sterne Spore Carbohydrate Content

    Energy Technology Data Exchange (ETDEWEB)

    Colburn, Heather A.; Wunschel, David S.; Antolick, Kathryn C.; Melville, Angela M.; Valentine, Nancy B.

    2011-06-01

    The expressed characteristics of biothreat agents may be impacted by variations in the culture environment, including growth medium formulation. The carbohydrate composition of B. anthracis spores has been well studied, particularly for the exosporium, which is the outermost spore structure. The carbohydrate composition of the exosporium has been demonstrated to be distinct from the vegetative form containing unique monosaccharides.

  12. Draft genome sequences of four thermophilic spore formers isolated from a dairy-processing environment

    NARCIS (Netherlands)

    Caspers, M.P.M.; Boekhorst, J.; Jong, de A.; Kort, R.; Nierop Groot, M.N.; Abee, T.

    2016-01-01

    Spores of thermophilic spore-forming bacteria are a common cause of contamination in dairy products. Here, we report draft genome sequences of four thermophilic strains from a milk-processing plant or standard milk, namely, a Geobacillus thermoglucosidans isolate (TNO-09.023), Geobacillus stearother

  13. Does spore ultrastructure mirror different dispersal strategies in mosses? A study of seven iberian orthotrichum species.

    Directory of Open Access Journals (Sweden)

    Nagore G Medina

    Full Text Available Most mosses have xerochastic dispersal (i.e., they open their capsules when conditions are dry, which is thought to favor long-distance dispersal. However, there are several species that use a hygrochastic strategy: spores are dispersed when conditions are wet. The significance of this strategy in the Mediterranean region is unknown. In this study, we explored whether ultrastructural features related to differences in spore resistance may explain these different strategies of spore dispersal. To this end, we examined the ultrastructural features of the spores of seven closely related species in the moss genus Orthotrichum. These species all grow as epiphytes in sub-Mediterranean forests, and the group includes both xerochastic and hygrochastic members. First, we found that the spore wall layers exhibit several features previously undescribed in mosses. Second, we discovered that there are only subtle differences in spore ultrastructure with regards to spore wall thickness, the degree of plastid development, or the storage substances used. We suggest that the hygrochastic dispersal in mosses from Mediterranean environments might be related to a safe-site strategy, rather than to drought avoidance, and we underscore the necessity of conducting spore ultrastructural studies on a greater number of bryophyte species.

  14. Decontamination of Bacillus spores adhered to iron and cement-mortar drinking water infrastructure in a model system using disinfectants.

    Science.gov (United States)

    Szabo, Jeffrey G; Meiners, Greg; Heckman, Lee; Rice, Eugene W; Hall, John

    2017-02-01

    Decontamination of Bacillus spores adhered to common drinking water infrastructure surfaces was evaluated using a variety of disinfectants. Corroded iron and cement-mortar lined iron represented the infrastructure surfaces, and were conditioned in a 23 m long, 15 cm diameter (75 ft long, 6 in diameter) pilot-scale drinking water distribution pipe system. Decontamination was evaluated using increased water velocity (flushing) alone at 0.5 m s(-1) (1.7 ft s(-1)), as well as free chlorine (5 and 25 mg L(-1)), monochloramine (25 mg L(-1)), chlorine dioxide (5 and 25 mg L(-1)), ozone (2.0 mg L(-1)), peracetic acid 25 mg L(-1)) and acidified nitrite (0.1 mol L(-1) at pH 2 and 3), all followed by flushing at 0.3 m s(-1) (1 ft s(-1)). Flushing alone reduced the adhered spores by 0.5 and 2.0 log10 from iron and cement-mortar, respectively. Log10 reduction on corroded iron pipe wall coupons ranged from 1.0 to 2.9 at respective chlorine dioxide concentrations of 5 and 25 mg L(-1), although spores were undetectable on the iron surface during disinfection at 25 mg L(-1). Acidified nitrite (pH 2, 0.1 mol L(-1)) yielded no detectable spores on the iron surface during the flushing phase after disinfection. Chlorine dioxide was the best performing disinfectant with >3.0 log10 removal from cement-mortar at 5 and 25 mg L(-1). The data show that free chlorine, monochloramine, ozone and chlorine dioxide followed by flushing can reduce adhered spores by > 3.0 log10 on cement-mortar.

  15. DECONTAMINATION ASSESSMENT OF BACILLUS ANTHRACIS, BACILLUS SUBTILIS, AND GEOBACILLUS STEAROTHERMOPHILUS SPORES ON INDOOR SURFACTS USING A HYDROGEN PERIOXIDE GAS GENERATOR

    Science.gov (United States)

    Aims: To evaluate the decontamination of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surface materials using hydrogen peroxide gas. Methods and Results: B. anthracis, B. subtilis, and G. Stearothermophilus spores were dried on seven...

  16. Germinant-enhanced decontamination of Bacillus spores adhered to iron and cement-mortar drinking water infrastructures.

    Science.gov (United States)

    Szabo, Jeffrey G; Muhammad, Nur; Heckman, Lee; Rice, Eugene W; Hall, John

    2012-04-01

    Germination was evaluated as an enhancement to decontamination methods for removing Bacillus spores from drinking water infrastructure. Germinating spores before chlorinating cement mortar or flushing corroded iron was more effective than chlorinating or flushing alone.

  17. DESTRUCTION OF ASPERGILLUS VERSICOLOR, PENICILLIUM CRYSOGENUM, STACHYBOTRYS CHARTARUM, AND CLADOSPORIUM CLADOSPORIDES SPORES USING CHEMICAL OXIDATION TREATMENT PROCESS

    Science.gov (United States)

    The survival of aqueous suspensions of Penicillium chrysogenum, Stachybotrys chartarum, Aspergillus versicolor, and Cladosporium cladosporioides spores was evaluated using various combinations of hydrogen peroxide and iron (II) as catalyst. Spores were suspended in water and trea...

  18. Nanoparticles Composed of Zn and ZnO Inhibit Peronospora tabacina Spore Germination in vitro and P. tabacina Infectivity on Tobacco Leaves

    Directory of Open Access Journals (Sweden)

    George Wagner

    2016-03-01

    Full Text Available Manufactured nanoparticles (NPs are increasingly being used for commercial purposes and certain NP types have been shown to have broad spectrum antibacterial activity. In contrast, their activities against fungi and fungi-like oomycetes are less studied. Here, we examined the potential of two types of commercially available Zn NPs (Zn NPs and ZnO NPs to inhibit spore germination and infectivity on tobacco leaves resulting from exposure to the fungi-like oomycete pathogen Peronospora tabacina (P. tabacina. Both types of NPs, as well as ZnCl2 and bulk ZnO control treatments, inhibited spore germination compared to a blank control. ZnO ENMs were shown to be a much more powerful suppressor of spore germination and infectivity than bulk ZnO. ZnO and Zn NPs significantly inhibited leaf infection at 8 and 10 mg·L−1, respectively. Both types of NPs were found to provide substantially higher concentration dependent inhibition of spore germination and infectivity than could be readily explained by the presence of dissolved Zn. These results suggest that both NP types have potential for use as economic, low-dose, potentially non-persistent anti-microbial agents against the oomycete P. tabacina.

  19. A microfluidic device for real-time monitoring of Bacillus subtilis bacterial spores during germination based on non-specific physicochemical interactions on the nanoscale level.

    Science.gov (United States)

    Zabrocka, L; Langer, K; Michalski, A; Kocik, J; Langer, J J

    2015-01-07

    A microfluidic device for studies on the germination of bacterial spores (e.g. Bacillus subtilis) based on non-specific interactions on the nanoscale is presented. A decrease in the population of spores during germination followed by the appearance of transition forms and an increase in the number of vegetative cells can be registered directly and simultaneously by using the microfluidic device, which is equipped with a conductive polymer layer (polyaniline) in the form of a nano-network. The lab-on-a-chip-type device, operating in a continuous flow regime, allows monitoring of germination of bacterial spores and analysis of the process in detail. The procedure is fast and accurate enough for quantitative real-time monitoring of the main steps of germination, including final transformation of the spores into vegetative cells. All of this is done without the use of biomarkers or any bio-specific materials, such as enzymes, antibodies and aptamers, and is simply based on an analysis of physicochemical interactions on the nanoscale level.

  20. Ultraweak luminescence from germinating resting spores of Entomophthora virulenta Hall et Dunn

    Directory of Open Access Journals (Sweden)

    Janusz Sławiński

    2014-08-01

    Full Text Available Germinating resting spores of Entomophthora virulenta Hall et Dunn emit ultraweak luminescence with the intensity of the order 100 photons • s-1 • cm-2 in the spectral region 200-750 nm. The emission kinetics and intensity depend on vitality and incubation temperature of the spores. The higher the ability of resting spores to germinate, the more intense the luminescence. Elevation of the incubation temperature to 50°C enhances ultraweak luminescence. The activation energy was found to be about 15 kJ • mol-1 and 5 kJ • mol-1 for nongerminating and germinating in 50% spores, respectively. The possibility of applying ultraweak luminescence as a simple assay for the spores vitality is discussed.

  1. Effect of High-pressure CO2 Processing on Bacterial Spores.

    Science.gov (United States)

    Rao, Lei; Bi, Xiufang; Zhao, Feng; Wu, Jihong; Hu, Xiaosong; Liao, Xiaojun

    2016-08-17

    High-pressure CO2 (HPCD) is a nonthermal technology that can effectively inactivate the vegetative forms of pathogenic and spoilage bacteria, yeasts, and molds at pressures less than 30 MPa and temperatures in the range of 20°C to 40°C. However, HPCD alone at moderate temperatures (20-40°C) is often insufficient to obtain a substantial reduction in bacterial spore counts because their structures are more complex than those of vegetative cells. In this review, we first thoroughly summarized and discussed the inactivation effect of HPCD treatment on bacterial spores. We then presented and discussed the kinetics by which bacterial spores are inactivated by HPCD treatment. We also summarized hypotheses drawn by different researchers to explain the mechanisms of spore inactivation by HPCD treatment. We then summarized the current research status and future challenges of spore inactivation by HPCD treatment.

  2. Protection of bacterial spores in space, a contribution to the discussion on Panspermia.

    Science.gov (United States)

    Horneck, G; Rettberg, P; Reitz, G; Wehner, J; Eschweiler, U; Strauch, K; Panitz, C; Starke, V; Baumstark-Khan, C

    2001-12-01

    Spores of Bacillus subtilis were exposed to space in the BIOPAN facility of the European Space Agency onboard of the Russian Earth-orbiting FOTON satellite. The spores were exposed either in dry layers without any protecting agent, or mixed with clay, red sandstone, Martian analogue soil or meteorite powder, in dry layers as well as in so-called 'artificial meteorites', i.e. cubes filled with clay and spores in naturally occurring concentrations. After about 2 weeks in space, their survival was tested from the number of colony formers. Unprotected spores in layers open to space or behind a quartz window were completely or nearly completely inactivated (survival rates in most cases Panspermia, may not provide sufficient protection for spores to survive. The data are also pertinent to search for life on Mars and planetary protection considerations for future missions to Mars.

  3. The Adsorption Properties of Bacillus atrophaeus Spore on Functionalized Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    P. Cortes

    2010-01-01

    Full Text Available An equilibrium study of Bacillus atrophaeus (B.a spores on functionalized Single-Wall Carbon Nanotubes (SWCNTs has been performed in order to characterize the adsorption properties of the spores/nanotubes complex. The carbon nanotubes here investigated were subjected to a two-step purification and functionalization treatment in order to introduce chemical groups on their basal planes. The inclusion of carboxyl functional groups on the nanotubes was corroborated by Raman and infrared spectroscopy. These carboxyl groups appear to enhance the nanotube-B.a. interaction by reacting with the proteinaceous pili appendages present on the spore surface. The adsorption data demonstrate that bacillus spores diffuse faster on functionalized carbon nanotubes than on as-received and purified nanomaterials. Transmission Electron Microscopy also shows that the chemically treated nanotubes resulted in a swollen nano-network which seems to further enhance the bacillus adsorption due to a more extensive spore-nanotube contact area.

  4. Efficacy of different cleaning and disinfection methods against Clostridium difficile spores: importance of physical removal versus sporicidal inactivation.

    Science.gov (United States)

    Rutala, William A; Gergen, Maria F; Weber, David J

    2012-12-01

    We tested the effectiveness of disinfectants and wipe methods against Clostridium difficile spores. Wiping with nonsporicidal agents (physical removal) was effective in removing more than 2.9 log(10) C. difficile spores. Wiping with sporicidal agents eliminated more than 3.90 log(10) C. difficile spores (physical removal and/or inactivation). Spraying with a sporicide eliminated more than 3.44 log(10) C. difficile spores but would not remove debris.

  5. Variability in DPA and calcium content in the spores of Clostridium species

    Directory of Open Access Journals (Sweden)

    Jan Jamroskovic

    2016-11-01

    Full Text Available Spores of a number of clostridial species, and their resistance to thermal treatment is a major concern for the food industry. Spore resistance to wet heat is related to the level of spore hydration, which is inversely correlated with the content of calcium and dipicolinic acid (DPA in the spore core. It is widely believed that the accumulation of DPA and calcium in the spore core is a fundamental component of the sporulation process for all endospore forming species. We have noticed heterogeneity in the heat resistance capacity and overall DPA/calcium content among the spores of several species belonging to Clostridium sensu stricto group: two C. acetobutylicum strains (DSM 792 and 1731, two C. beijerinckii strains (DSM 791 and NCIMB 8052, and a C. collagenovorans strain (DSM 3089. A C. beijerinckii strain (DSM 791 and a C. acetobutylicum strain (DSM 792 display low Ca and DPA levels. In addition, these two species, with the lowest average Ca/DPA content amongst the strains considered, also exhibit minimal heat resistance. There appears to be no correlation between the Ca/DPA content and the phylogenetic distribution of the C. acetobutylicum and C. beijerinckii species based either on the 16S rRNA or the spoVA gene. This finding suggests that a subset of Clostridium sensu stricto species produce spores with low resistance to wet heat. Additionally, analysis of individual spores using STEM-EDS and STXM revealed that DPA and calcium levels can also vary amongst individual spores in a single spore population.

  6. Airborne bacterial spore counts by terbium-enhanced luminescence detection: pitfalls and real values.

    Science.gov (United States)

    Li, Qingyang; Dasgupta, Purnendu K; Temkins, Henry K

    2008-04-15

    Bacterial spore determination by terbium(III)-dipicolinate luminescence has been reported by several investigators. We collected spore samples with a cyclone and extracted dipicolinic acid (DPA) in-line with hot aqueous dodecylamine, added Tb(III) in a continuous-flow system and detected the Tb(III)-DPA with a gated liquid core waveguide fluorescence detector with a flashlamp excitation source. The absolute limit of detection (LOD) for the system was equivalent to 540 B. subtilis spores (for a 1.8 m3 sample volume (t = 2 h, Q = 15 L/min), concentration LOD is 0.3 spores/L air). Extant literature suggests that, from office to home settings, viable spore concentrations range from 0.1 to 10 spores/L; however, these data have never been validated. Previously reported semiautomated instrumentation had an LOD of 50 spores/L. The present system was tested at five different location settings in Lubbock, Texas. The apparent bacterial spore concentrations ranged from 9 to 700 spores/L and only occasionally exhibited the same trend as the simultaneously monitored total optical particle counts in the > or = 0.5 microm size fraction. However, because the apparent spore counts sometimes were very large relative to the 0.5+ microm size particle counts, we investigated potential positive interferences. We show that aromatic acids are very likely large interferents. This interference typically constitutes approximately 70% of the signal and can be as high as 95%. It can be completely removed by prewashing the particles.

  7. Regulation of Clostridium difficile spore germination by the CspA pseudoprotease domain.

    Science.gov (United States)

    Kevorkian, Yuzo; Shirley, David J; Shen, Aimee

    2016-03-01

    Clostridium difficile is a spore-forming obligate anaerobe that is a leading cause of healthcare-associated infections. C. difficile infections begin when its metabolically dormant spores germinate in the gut of susceptible individuals. Binding of bile salt germinants to the Csp family pseudoprotease CspC triggers a proteolytic signaling cascade consisting of the Csp family protease CspB and the cortex hydrolase SleC. Conserved across many of the Clostridia, Csp proteases are subtilisin-like serine proteases that activate pro-SleC by cleaving off its inhibitory pro-peptide. Active SleC degrades the protective cortex layer, allowing spores to resume metabolism and growth. This signaling pathway, however, is differentially regulated in C. difficile, since CspC functions both as a germinant receptor and regulator of CspB activity. CspB is also produced as a fusion to a catalytically inactive CspA domain that subsequently undergoes interdomain processing during spore formation. In this study, we investigated the role of the CspA pseudoprotease domain in regulating C. difficile spore germination. Mutational analyses revealed that the CspA domain controls CspC germinant receptor levels in mature spores and is required for optimal spore germination, particularly when CspA is fused to the CspB protease. During spore formation, the YabG protease separates these domains, although YabG itself is dispensable for germination. Bioinformatic analyses of Csp family members suggest that the CspC-regulated signaling pathway characterized in C. difficile is conserved in related Peptostreptococcaceae family members but not in the Clostridiaceae or Lachnospiraceae. Our results indicate that pseudoproteases play critical roles in regulating C. difficile spore germination and highlight that diverse mechanisms control spore germination in the Clostridia.

  8. Mass production of spores of lactic acid-producing Rhizopus oryzae NBRC 5384 on agar plate.

    Science.gov (United States)

    Yamane, Tsuneo; Tanaka, Ryosuke

    2013-01-01

    Mass production of sporangiospores (spores) of Rhizopus oryzae NBRC 5384 (identical to NRRL 395 and ATCC 9363) on potato-dextrose-agar medium was studied aiming at starting its L(+)-lactic acid fermentation directly from spore inoculation. Various parameters including harvest time, sowed spore density, size of agar plate, height of air space, and incubation mode of plate (agar-on-bottom or agar-on-top) were studied. Ordinarily used shallow Petri dishes were found out to be unsuitable for the full growth of R. oryzae sporangiophores. In a very wide range of the sowed spore density, the smaller it was, the greater the number of the harvested spores was. It was also interesting to find out that R. oryzae grown downward vertically with a deep air space in an agar-on-top mode gave larger amount of spores than in an agar-on-bottom mode at 30°C for 7-day cultivation. Scale-up of the agar plate culture from 26.4 to 292 cm(2) was studied, resulting in the proportional relationship between the number of the harvested spores/plate and the plate area in the deep Petri dishes. The number of plates of 50 cm in diameter needed for 100 m(3) industrial submerged fermentation started directly from 2 × 10(5) spores/mL inoculum size was estimated as about 6, from which it was inferred that such a fermentation would be feasible. Designing a 50 cm plate and a method of spreading and collecting the spores were suggested. Bioprocess technological significance of the "full-scale industrial submerged fermentation started directly from spore inoculation omitting pre-culture" has been discussed.

  9. A Gompertz regression model for fern spores germination

    Directory of Open Access Journals (Sweden)

    Gabriel y Galán, Jose María

    2015-06-01

    Full Text Available Germination is one of the most important biological processes for both seed and spore plants, also for fungi. At present, mathematical models of germination have been developed in fungi, bryophytes and several plant species. However, ferns are the only group whose germination has never been modelled. In this work we develop a regression model of the germination of fern spores. We have found that for Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei and Polypodium feuillei species the Gompertz growth model describe satisfactorily cumulative germination. An important result is that regression parameters are independent of fern species and the model is not affected by intraspecific variation. Our results show that the Gompertz curve represents a general germination model for all the non-green spore leptosporangiate ferns, including in the paper a discussion about the physiological and ecological meaning of the model.La germinación es uno de los procesos biológicos más relevantes tanto para las plantas con esporas, como para las plantas con semillas y los hongos. Hasta el momento, se han desarrollado modelos de germinación para hongos, briofitos y diversas especies de espermatófitos. Los helechos son el único grupo de plantas cuya germinación nunca ha sido modelizada. En este trabajo se desarrolla un modelo de regresión para explicar la germinación de las esporas de helechos. Observamos que para las especies Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei y Polypodium feuillei el modelo de crecimiento de Gompertz describe satisfactoriamente la germinación acumulativa. Un importante resultado es que los parámetros de la regresión son independientes de la especie y que el modelo no está afectado por variación intraespecífica. Por lo tanto, los resultados del trabajo muestran que la curva de Gompertz puede representar un modelo general para todos los helechos leptosporangiados

  10. Fern spore longevity in saline water: can sea bottom sediments maintain a viable spore bank?

    NARCIS (Netherlands)

    Groot, de G.A.; During, H.

    2013-01-01

    Freshwater and marine sediments often harbor reservoirs of plant diaspores, from which germination and establishment may occur whenever the sediment falls dry. Therewith, they form valuable records of historical interand intraspecific diversity, and are increasingly exploited to facilitate diversity

  11. Cold-air atmospheric pressure plasma against Clostridium difficile spores: a potential alternative for the decontamination of hospital inanimate surfaces.

    Science.gov (United States)

    Claro, Tânia; Cahill, Orla J; O'Connor, Niall; Daniels, Stephen; Humphreys, Hilary

    2015-06-01

    Clostridium difficile spores survive for months on environmental surfaces and are highly resistant to decontamination. We evaluated the effect of cold-air plasma against C. difficile spores. The single-jet had no effect while the multi-jet achieved 2-3 log10 reductions in spore counts and may augment traditional decontamination.

  12. Myxobolus turpisrotundus (Myxosporea: Bivalvulida) spores with caudal appendages: investigating the validity of the genus Henneguya with morphological and molecular evidence.

    Science.gov (United States)

    Liu, Yang; Whipps, Christopher M; Gu, Z M; Zeng, L B

    2010-08-01

    Spores of the myxozoan parasite Myxobolus turpisrotundus Zhang 2009 were observed for the first time bearing caudal appendages. Most spores had the typical Myxobolus spp. morphology, but approximately 10% of spores possessed a spore body that was slightly elongated with a short tail projecting from the spore valve. In other spores, the tail was much more clearly visible and elongate. The spore body of these unusual spores is consistent in morphology and dimension to the normal spores of M. turpisrotundus. Both spore types were found within individual cysts, and the small subunit ribosomal RNA (ssrRNA) gene sequence from parasite cysts of this type was nearly identical to the previously published sequence of M. turpisrotundus from allogynogenetic gibel carp Carassius auratus gibelio (Bloch). The phenomenon of Myxobolus spores with caudal appendages provides additional evidence that the use of this character to separate Myxobolus and Henneguya into distinct genera is not reflective of an evolutionarily accurate classification scheme. Phylogenetic analysis of ssrDNA sequence from Myxobolus and Henneguya species showed clustering of species in some locations of the tree, but ultimately these genera are intermixed. The use of a single character to delineate species in the two most species-rich myxozoan genera has been consistently challenged where DNA analyses are used. The present finding of a single species bearing both Myxobolus-type and Henneguya-type spores emphasizes the inadequacy of this classification scheme, and highlights the need for careful consideration of these variable characteristics when describing myxozoan species.

  13. Quantification of the impact of single and multiple mild stresses on outgrowth heterogeneity of Bacillus cereus spores

    NARCIS (Netherlands)

    Melis, van C.C.J.; Besten, den H.M.W.; Nierop Groot, M.N.; Abee, T.

    2014-01-01

    Outgrowth heterogeneity of bacterial spore populations complicates both prediction and efficient control of spore outgrowth. In this study, the impact of mild preservation stresses on outgrowth of Bacillus cereus ATCC 14579 spores was quantified during the first stages of outgrowth. Heterogeneity in

  14. Effects of nifedipine on gravi-dependent germination of moss spores

    Science.gov (United States)

    Khorkavtsiv, O. Y.; Demkiv, O. T.

    Influence of gravity on germination of spores and dependence of the generation of a polar axis on a Ca2+ influx were investigated. The germination of spores does not depend on gravity but outgrowth polarity is controlled by light and gravity (Sytnik et al., 1989; Pundiak et al., 2001). We have shown that gravity determines the polarity of germination of spores and development of rhizoid and chloronemal outgrowths in both moss species -- Ceratodon purpureus and Pohlia nutans, the alignment of polar of germinating spores in C. purpureus, however, is less dependent on gravistimulus than in P. nutans. In 48 h after sowing onto culture medium+0,2% glucose in vertically oriented petri dishes in darkness spores of P. nutans germinated positively gravitropic rhizoid at the lower spore side and negatively gravitropic chloronema at the opposite one. The germination of C. purpureus spores is similar but the outgrowths show the lower level of alignment to the gravity vector than that of P. nutans, the dispersion of angles being 8,9 vs. 1,2 respectively. The cellular mechanism by which gravity acts remains unknown. The intracellular signaling Ca2+ ions play a crucial role in gravity perception and ability of a single cell to respond to gravity. We determined relative intensity of Ca2+ luminescence in the spores before their germination and at the early stages of outgrowth formation after treatment with the nifedipine and in a dependence on gravity vector. Gravity determined the position of outgrowth initiation zone and later on the growth direction of spore filaments. Treatment with nifedipine suppressed the gravity-directed calcium channel influx and distrupted polar growth of outgrowths. In experiments with calcium channel blocker sterilized spores were pregerminated on normal Knop's agar one day after were transferred to 50 μ M nifedipine just before emergence of the germ tube. After 48 h on nifedipine treatment, 50% spores did not germinate, 35% grew apolarily and in 15

  15. FTIR Spectroscopy for Bacterial Spore Identification and Classification

    Energy Technology Data Exchange (ETDEWEB)

    Valentine, Nancy B.; Johnson, Timothy J.; Su, Yin-Fong; Forrester, Joel B.

    2006-12-31

    The ability to distinguish endospores from each other, from vegetative cells, and from background particles has been demonstrated by PNNL and several other laboratories using various analytical techniques such as MALDI and SIMS. Recent studies at PNNL using Fourier transform Infrared (FTIR) spectroscopy combined with statistical analysis have shown the ability to characterize and discriminate bacterial spores and vegetative bacteria from each other, as well as from background interferents. In some cases it is even possible to determine the taxonomical identity of the species using FTIR. This effort has now grown to include multiple species of bacterial endospores, vegetative cells, and background materials. The present work reports on advances in being able to use FTIR, or IR in combination with other techniques, for rapid and reliable discrimination.

  16. Evaluating Composite Sampling Methods of Bacillus spores at Low Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Hess, Becky M.; Amidan, Brett G.; Anderson, Kevin K.; Hutchison, Janine R.

    2016-10-13

    Restoring facility operations after the 2001 Amerithrax attacks took over three months to complete, highlighting the need to reduce remediation time. The most time intensive tasks were environmental sampling and sample analyses. Composite sampling allows disparate samples to be combined, with only a single analysis needed, making it a promising method to reduce response times. We developed a statistical experimental design to test three different composite sampling methods: 1) single medium single pass composite: a single cellulose sponge samples multiple coupons; 2) single medium multi-pass composite: a single cellulose sponge is used to sample multiple coupons; and 3) multi-medium post-sample composite: a single cellulose sponge samples a single surface, and then multiple sponges are combined during sample extraction. Five spore concentrations of Bacillus atrophaeus Nakamura spores were tested; concentrations ranged from 5 to 100 CFU/coupon (0.00775 to 0.155CFU/cm2, respectively). Study variables included four clean surface materials (stainless steel, vinyl tile, ceramic tile, and painted wallboard) and three grime coated/dirty materials (stainless steel, vinyl tile, and ceramic tile). Analysis of variance for the clean study showed two significant factors: composite method (p-value < 0.0001) and coupon material (p-value = 0.0008). Recovery efficiency (RE) was higher overall using the post-sample composite (PSC) method compared to single medium composite from both clean and grime coated materials. RE with the PSC method for concentrations tested (10 to 100 CFU/coupon) was similar for ceramic tile, painted wall board, and stainless steel for clean materials. RE was lowest for vinyl tile with both composite methods. Statistical tests for the dirty study showed RE was significantly higher for vinyl and stainless steel materials, but significantly lower for ceramic tile. These results suggest post-sample compositing can be used to reduce sample analysis time when

  17. Evaluating Composite Sampling Methods of Bacillus Spores at Low Concentrations

    Science.gov (United States)

    Hess, Becky M.; Amidan, Brett G.; Anderson, Kevin K.; Hutchison, Janine R.

    2016-01-01

    Restoring all facility operations after the 2001 Amerithrax attacks took years to complete, highlighting the need to reduce remediation time. Some of the most time intensive tasks were environmental sampling and sample analyses. Composite sampling allows disparate samples to be combined, with only a single analysis needed, making it a promising method to reduce response times. We developed a statistical experimental design to test three different composite sampling methods: 1) single medium single pass composite (SM-SPC): a single cellulose sponge samples multiple coupons with a single pass across each coupon; 2) single medium multi-pass composite: a single cellulose sponge samples multiple coupons with multiple passes across each coupon (SM-MPC); and 3) multi-medium post-sample composite (MM-MPC): a single cellulose sponge samples a single surface, and then multiple sponges are combined during sample extraction. Five spore concentrations of Bacillus atrophaeus Nakamura spores were tested; concentrations ranged from 5 to 100 CFU/coupon (0.00775 to 0.155 CFU/cm2). Study variables included four clean surface materials (stainless steel, vinyl tile, ceramic tile, and painted dry wallboard) and three grime coated/dirty materials (stainless steel, vinyl tile, and ceramic tile). Analysis of variance for the clean study showed two significant factors: composite method (pmethod compared to the SM-SPC and SM-MPC methods. RE with the MM-MPC method for concentrations tested (10 to 100 CFU/coupon) was similar for ceramic tile, dry wall, and stainless steel for clean materials. RE was lowest for vinyl tile with both composite methods. Statistical tests for the dirty study showed RE was significantly higher for vinyl and stainless steel materials, but lower for ceramic tile. These results suggest post-sample compositing can be used to reduce sample analysis time when responding to a Bacillus anthracis contamination event of clean or dirty surfaces. PMID:27736999

  18. The use of bacterial spore formers as probiotics.

    Science.gov (United States)

    Hong, Huynh A; Duc, Le Hong; Cutting, Simon M

    2005-09-01

    The field of probiosis has emerged as a new science with applications in farming and aqaculture as alternatives to antibiotics as well as prophylactics in humans. Probiotics are being developed commercially for both human use, primarily as novel foods or dietary supplements, and in animal feeds for the prevention of gastrointestinal infections, with extensive use in the poultry and aquaculture industries. The impending ban of antibiotics in animal feed, the current concern over the spread of antibiotic resistance genes, the failure to identify new antibiotics and the inherent problems with developing new vaccines make a compelling case for developing alternative prophylactics. Among the large number of probiotic products in use today are bacterial spore formers, mostly of the genus Bacillus. Used primarily in their spore form, these products have been shown to prevent gastrointestinal disorders and the diversity of species used and their applications are astonishing. Understanding the nature of this probiotic effect is complicated, not only because of the complexities of understanding the microbial interactions that occur within the gastrointestinal tract (GIT), but also because Bacillus species are considered allochthonous microorganisms. This review summarizes the commercial applications of Bacillus probiotics. A case will be made that many Bacillus species should not be considered allochthonous microorganisms but, instead, ones that have a bimodal life cycle of growth and sporulation in the environment as well as within the GIT. Specific mechanisms for how Bacillus species can inhibit gastrointestinal infections will be covered, including immunomodulation and the synthesis of antimicrobials. Finally, the safety and licensing issues that affect the use of Bacillus species for commercial development will be summarized, together with evidence showing the growing need to evaluate the safety of individual Bacillus strains as well as species on a case by case by basis.

  19. Temporaly germinating rhythms of moss Funaria hygrometrica Hedw. spores

    Science.gov (United States)

    Pundiak, O.; Demkiv, O.

    The process of an organism development is regular and gradual. These characteristics of the development are especially evident in archegonial plants. It was shown that spores of moss Funar ia hygrometrica Hedw. in Knop's nutrient medium with 0,2% glucose in the dark in vertical orientation of Petry dishes, germinated polarly depending on gravity direction. At the begining, the primary rhyziod developed being usually directed downwards and then after 24 hours primary chloronema developed growing usually upwards. The amyloplasts sedimentation was shown before the rhyzoid and chloronema formation. It determines not only the time, but spatial orientation of the primary rhyzoid and chloronema (Pundjak at al., 2001). EGTA in concentration of 510- 5 M inhibited the initiation of the primary rhyzoid. The primary chloronema developed as usual in 48 h after the spores sowing. Temporary cooling caused analogical effect. Basing on these results we drew the conclusion that the primary rhyzoid and chloronema differently react on the action of EGTA and the cooling. The primary chloronema was more tolerant then the rhyzoid and maintained its usual gravisensitivy. Thus, we can think that EGTA and the cooling stop the development of primary rhyzoid, but it does not disturb physiological rhythm which underlais in the base of the function of the biological clock. The stability of biological rhythms and their indeterminism in respect of described above external and internal factors is real thanks to dissipation, which makes considerable interval of uncertainties of distributions of distances between segments of biopolymers and thus, of their fermentative activities (Pundjak,2001). Therefore the rise of biological clocks of each organism is in certain sense transcendental.

  20. The interactive effect of phosphorus and nitrogen on "in vitro" spore germination of Glomus etunicatum Becker & Gerdemann, root growth and mycorrhizal colonization

    Directory of Open Access Journals (Sweden)

    Bressan Wellington

    2001-01-01

    Full Text Available The effects of P and N amendment and its interactions on spore germination, root growth and colonized root length by Glomus etunicatum Becker & Gerdemann (INVAM S329 was studied "in vitro" in RiT - DNA transformed roots of Anthylis vulneraria sub sp. Sampaiana (Kidney vetch. Three N media concentrations (5, 10 and 50 mg/l at P constant level (2 mg/l and three P media concentrations (2, 10 and 20 mg/l at N constant level (5 mg/l were utilized as a treatment. Bécard & Fortin medium was used as a basal medium for root growth and colonized root length, and water/agar (0.8% media was the control for spore germination. Spore germination of G. etunicatum at low P level was reduced by N addition in relation to the control media, and at low N level addition of P stimulated spore germination. Total root length was stimulated by N addtion at low P level, but no significant difference (p£0.05 was observed between 10 and 50 mg/l of N. P addition at low N level media also stimulated total root growth, and a significant difference (p£0.05 was observed among P concentrations. Colonized root length by G. etunicatum increased significantly (p£0.05 with P additions at low N levels. Under low P level no significant differences was found between 10 and 50 mg/l of N. These results demonstrate that the interaction between P and N affect differently spore germination, root growth and colonized root lenght.