| colony shape as a genetic trait in the pattern-forming bacillus mycoides. | bacillus mycoides flügge, a gram-positive, non-motile soil bacterium assigned to bacillus cereus group, grows on agar as chains of cells linked end to end, forming radial filaments curving clock- or counter-clockwise (sin or dx morphotypes). the molecular mechanism causing asymmetric curving is not known: our working hypothesis considers regulation of filamentous growth as the prerequisite for these morphotypes. | 2002 | 12429070 |
| magnetized carbonyl iron and insoluble zirconium hydroxide mixture facilitates bacterial concentration and separation from nonfat dry milk. | a mixture of magnetized carbonyl iron and insoluble zirconium hydroxide was investigated for its ability to concentrate various foodborne pathogens from 25-ml samples of reconstituted nonfat dry milk. each sample was artificially contaminated with 10(3) to 10(6) cfu/25 ml of representative foodborne pathogens (salmonella enterica serovar enteritidis, listeria monocytogenes, and bacillus cereus spores) and processed for bacterial concentration with high-speed centrifugation for the primary concen ... | 2002 | 12430708 |
| search for potential vaccine candidate open reading frames in the bacillus anthracis virulence plasmid pxo1: in silico and in vitro screening. | a genomic analysis of the bacillus anthracis virulence plasmid pxo1, aimed at identifying potential vaccine candidates and virulence-related genes, was carried out. the 143 previously defined open reading frames (orfs) (r. t. okinaka, k. cloud, o. hampton, a. r. hoffmaster, k. k. hill, p. keim, t. m. koehler, g. lamke, s. kumano, j. mahillon, d. manter, y. martinez, d. ricke, r. svensson, and p. j. jackson, j. bacteriol. 181:6509-6515, 1999) were subjected to extensive sequence similarity search ... | 2002 | 12438358 |
| the enterotoxin t (bcet) from bacillus cereus can probably not contribute to food poisoning. | a polymerase chain reaction (pcr) fragment from strain nvh 38 (containing bcet) was cloned, sequenced and expressed in escherichia coli. this sequence showed 50-60% identity to the original. when this bcet clone was expressed in e. coli no biological activity was found in either supernatants or cell extracts. cell extracts from the bacillus cereus strains (nvh 38 and b-4ac) were also negative on vero cells. neutralisation of supernatant from b. cereus b-4ac using a monoclonal antibody (reacting ... | 2002 | 12445654 |
| amplified fragment length polymorphism (aflp) analysis of clostridium novyi, c. perfringens and bacillus cereus isolated from injecting drug users during 2000. | as part of the follow-up investigations associated with an outbreak of severe illness and death among illegal injecting drug users during 2000, 43 cultures of clostridium novyi type a, 40 c. perfringens type a and 6 isolates of bacillus cereus were characterised by amplified fragment length polymorphism (aflp) analysis. among the 43 c. novyi isolates, 23 different aflp profiles were detected. the same aflp profile was detected in isolates from 18 drug users investigated during 2000 from scotland ... | 2002 | 12448684 |
| an investigation into the microflora of heroin. | in 2000, an unusual increase of morbidity and mortality among illegal injecting drug users in the uk and ireland was reported and clostridium novyi was identified as the likely source of the serious infection, although infections due to c. botulinum and bacillus cereus were also reported. because heroin was a possibile source of infection, this study investigated the microflora of heroin samples seized in england during 2000 and 2002. two methods were developed for the examination of the microfl ... | 2002 | 12448685 |
| toward an understanding of microbial communities through analysis of communication networks. | bacteria receive signals from diverse members of their biotic environment. they sense their own species through the process of quorum sensing, which detects the density of bacterial cells and regulates functions such as bioluminescence, virulence, and competence. bacteria also respond to the presence of other microorganisms and eukaryotic hosts. most studies of microbial communication focus on signaling between the microbe and one other organism for empirical simplicity and because few experimen ... | 2002 | 12448752 |
| broadband 10-300 ghz stimulus-response sensing for chemical and biological entities. | by illuminating the sample with a broadband 10-300 ghz stimulus and coherently detecting the response, we obtain reflection and transmission spectra of common powdered substances, and compare them as a starting point for distinguishing concealed threats in envelopes and on personnel. because these samples are irregular and their dielectric properties cannot be modulated, however, the spectral information we obtain is largely qualitative. to show how to gain quantitative information on biological ... | 2002 | 12452568 |
| isolation of nisin-producing lactococcus lactis wnc 20 strain from nham, a traditional thai fermented sausage. | a total of 14,020 lactic acid bacteria (lab) were isolated from nham and screened for bacteriocin production. one lactococcus lactis strain wnc 20 produced a bacteriocin that not only inhibited closely related lab, but also some food-borne pathogens including listeria monocytogenes, clostridium perfringens, bacillus cereus and staphylococcus aureus. biochemical studies revealed that the bacteriocin was heat-stable even at autoclaving temperature (121 degrees c for 15 min) and was active over a w ... | 2003 | 12457588 |
| cytotoxic potential of industrial strains of bacillus sp. | the cytotoxic potential of selected strains of bacillus licheniformis, bacillus amyloliquefaciens, and bacillus subtilis, used in the production of industrial enzyme products, has been assessed. cytotoxicity was determined in chinese hamster ovary (cho-k1) cells by measuring total cellular metabolic activity using the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (mtt). initially the mtt assay was validated against toxigenic strains of bacillus cereus, to define t ... | 2002 | 12460750 |
| [street-vendor foods: quality of ice creams, sherbets and sorbets sold in the urban agglomeration of antananarivo]. | a survey of selling conditions and bacteriological examinations of ice-cream was carried-out in antananarivo from june 1996 to may 1997. the way of investigation by vendors and of bacteriological examinations were widely described. sellers had classic features of a street-vended food vendor: uneducated, no having professional training and mishandling foodstuffs. 202 samples of ice-cream were collected. the contamination prevalence rate was of 95% +/- 3.7%. salmonella typhimurium was isolated fro ... | 1996 | 12463022 |
| dna sequence conservation between the bacillus anthracis pxo2 plasmid and genomic sequence from closely related bacteria. | complete sequencing and annotation of the 96.2 kb bacillus anthracis plasmid, pxo2, predicted 85 open reading frames (orfs). bacillus cereus and bacillus thuringiensis isolates that ranged in genomic similarity to b. anthracis, as determined by amplified fragment length polymorphism (aflp) analysis, were examined by pcr for the presence of sequences similar to 47 pxo2 orfs. | 2002 | 12473162 |
| role of the c-domain in the biological activities of clostridium perfringens alpha-toxin. | clostridium perfringens alpha-toxin (370 residues) possesses hemolytic and lethal activities as well as the enzymatic activity of phospholipase c (plc). in this study we examined the role of the c-domain (251-370 residues; cp251- 370) in biological activities of the toxin. the n-domain (1-250 residues; cp1- 250) of the alpha-toxin as well as the bacillus cereus phospholipase c (bcplc) possessed plc activity, but did not bind to rabbit erythrocytes and lyse them. a hybrid protein (bc-cp251-370) c ... | 2002 | 12477243 |
| application of a real-time biosensor to detect bacteria in platelet concentrates. | a spore-based biosensor for detecting low levels of bacteria in real-time has been recently developed. the system (termed lexsas, label-free exponential signal-amplification system) exploits spore's ability to produce fluorescence when sensing neighboring bacterial cells. we studied the lexsas as a possible approach for identifying bacterially contaminated platelet concentrates prior to transfusion because the system offers rapid analysis, high sensitivity, and low cost. if successful, this appr ... | 2003 | 12480543 |
| production and characterization of tannase from bacillus cereus kbr9. | a tannase-producing soil bacteria has been isolated and identified as bacillus cereus. it can degrade tannic acid and produce maximum tannase (0.22 u/ml) at stationary phases of growth (24 h). maximum growth and enzyme production occurred with initial medium ph of 4.5-5.0. partial purified tannase showed optimum activity at ph 4.5 and 40 degrees c. it remains stable up to 30 degrees c and ph 4.5 to 5.0. the enzyme is salt tolerant, stable up to 2 m of nacl and retains 82% original activity in 3 ... | 2001 | 12483613 |
| bacillus cereus, bacillus thuringiensis and bacillus mycoides differentiation using a pcr-re technique. | a method was developed to differentiate between bacillus cereus, bacillus mycoides and bacillus thuringiensis using the polymerase chain reaction combined with a restriction endonuclease (pcr-re) technique. this fast and simple protocol, applied to pure culture strains, was developed using the gyrb dna sequence, as previously proposed by other authors. strains from international collections were used to optimize the method which was then applied to the identification of strains isolated from foo ... | 2003 | 12485751 |
| identification of aerobic mesophilic bacilli isolated from board and paper products containing recycled fibres. | to identify aerobic mesophilic bacteria isolated from coreboard, kitchen roll paper and food packaging boards containing recycled fibres and to create a rapid fingerprint-based database for their identification. | 2003 | 12492920 |
| antibacterial activity of a stearic acid derivative from stemodia foliosa. | from the hexane-soluble fraction of an ethanol extract from leaves and stems of stemodia foliosa (scrophulariaceae), the new stearic acid 4-[(n-pentoxy)phenethyl] ester (1) was isolated. this compound exhibited antibacterial properties at 10 microg/ml concentration by using disc diffusion method against gram-positive bacteria bacillus cereus and bacillus subtilis and fast-acid bacterium mycobacterium fortuitum. the structure of the new compound was elucidated by spectroscopic methods and by chem ... | 2002 | 12494347 |
| effect of dissolved carbon dioxide on thermal inactivation of microorganisms in milk. | postpasteurization addition of co2 inhibits growth of certain microorganisms in dairy products, but few workers have investigated the effect of co2 on the thermal inactivation of microorganisms during pasteurization. concentrations of co2 ranging from 44 to 58 mm added to raw whole milk significantly (p < 0.05) reduced the number of surviving standard plate count (spc) organisms in milk heated over the range of 67 to 93 degrees c. a decrease in thermal survival rates (d-values) for pseudomonas f ... | 2002 | 12495011 |
| altered ability of bacillus cereus spores to grow under unfavorable conditions (presence of nisin, low temperature, acidic ph, presence of nacl) following heat treatment during sporulation. | the effect of thermal treatment on the heat resistance of bacillus cereus spores and their ability to germinate and grow under more or less adverse conditions during sporulation was investigated. spores produced by sporulating cells subjected to a mild heat treatment (at a temperature 15 degrees c higher than the growth temperature) were more resistant to heat than were spores produced by untreated cells. spore germination and growth (the lag time, the maximal growth rate, and the occurrence of ... | 2002 | 12495012 |
| bidirectional control of sphingomyelinase activity and surface topography in lipid monolayers. | lipid lateral organization is increasingly found to modulate membrane-bound enzymes. we followed in real time the reaction course of sphingomyelin (sm) degradation by bacillus cereus sphingomyelinase (smase) of lipid monolayers by epifluorescence microscopy. there is evidence that formation of ceramide (cer), a lipid second messenger, drives structural reorganization of membrane lipids. our results provide visual evidence that smase activity initially alters surface topography by inducing phase ... | 2002 | 12496108 |
| crystal structure and site-directed mutagenesis of enzymatic components from clostridium perfringens iota-toxin. | iota-toxin from clostridium perfringens type e is an adp-ribosylating toxin (adprt) that adp-ribosylates actin, which is lethal and dermonecrotic in mammals. it is a binary toxin composed of an enzymatic component (ia) and a binding component (ib). ia adp-ribosylates g-actin at arginine 177, resulting in the depolymerization of the actin cytoskeleton. here, we report on studies of the structure-function relationship by the crystal structures of ia complexed with nadh and nadph (at 1.8 a and 2.1 ... | 2003 | 12498797 |
| enterotoxigenicity and cytotoxicity of bacillus thuringiensis strains and development of a process for cry1ac production. | bacillus thuringiensis is indistinguishable from bacillus cereus except for the production of insecticidal crystal proteins (icps). b. thuringiensis strains may show enterotoxin profiles and toxin levels similar to those of b. cereus strains isolated from food-poisoning cases. it is important for the food industry and farmers to consider that with the application of b. thuringiensis strains to crops, their spores may be introduced into the human food chain. in this study, 59 b. thuringiensis str ... | 2003 | 12502392 |
| eggshell matrix proteins as defense mechanism of avian eggs. | this study focused on the role of eggshell matrix proteins as a function of potential natural antimicrobial defenses of avian eggs. the electrophoretic profile of sds-page showed that the soluble eggshell matrix proteins had three major bands of 15 000, 36 000, and 66 000 and several minor bands comprising 17 000, 25 000, 30 000, and 75 000, while insoluble matrix proteins were consisting of various bands comprising at least 16 distinct migration bands between 10 000 and 200 000. three bacteria ... | 2003 | 12502416 |
| presence of erm genes among macrolide-resistant gram-positive bacteria isolated from danish farm soil. | the presence of erm genes was investigated among macrolide-resistant gram-positive bacteria isolated from soil samples collected from four danish farms that had been treated with animal waste. soil samples were collected before, a few days after spread and 1 1/2 months and 5 months later. in 33% (9/27) of these isolates, an erm gene was detected using pcr. eight isolates were positive for erm(b) and one isolate was positive for erm(c). no isolates contained erm(a), erm(d) or erm(f). the positive ... | 2002 | 12503914 |
| influence of ph and temperature on growth of bacillus cereus in vegetable substrates. | bacillus cereus is a food-borne pathogen which most often contaminates foods of plant origin. spores of psychrotrophic strains have the ability to germinate and grow at refrigeration temperatures in different vegetable substrates, such as carrot broth, zucchini broth, and cooked carrot purée. in some circumstances, factors such as ph, heat treatment, and storage temperature play a fundamental role in controlling the growth of these psychrotrophic strains and in extending the shelf life of refrig ... | 2003 | 12505461 |
| bacillus anthracis diverges from related clades of the bacillus cereus group in 16s-23s ribosomal dna intergenic transcribed spacers containing trna genes. | mung bean nuclease treatment of 16s-23s ribosomal dna intergenic transcribed spacers (its) amplified from several strains of the six species of the bacillus cereus group showed that b. anthracis davis te702 and b. mycoides g2 have other intermediate fragments in addition to the 220- and 550-bp homoduplex fragments typical of the b. cereus group. long and intermediate homoduplex its fragments from strains davis te702 and g2 and from another 19 strains of the six species were sequenced. two main t ... | 2003 | 12513974 |
| production of proinflammatory mediators by indoor air bacteria and fungal spores in mouse and human cell lines. | we compared the inflammatory and cytotoxic responses caused by household mold and bacteria in human and mouse cell lines. we studied the fungi aspergillus versicolor, penicillium spinulosum, and stachybotrys chartarum and the bacteria bacillus cereus, pseudomonas fluorescens, and streptomyces californicus for their cytotoxicity and ability to stimulate the production of inflammatory mediators in mouse raw264.7 and human 28sc macrophage cell lines and in the human a549 lung epithelial cell line i ... | 2003 | 12515684 |
| lethal factor to mice produced by escherichia coli isolated from chickens with swollen head syndrome. | a lethal toxin similar to bacillus cererus lethal toxin was detected in the culture supernatants of escherichia coli isolated from chickens with swollen head syndrome. the lethal activity was heat-labile, protease-sensitive and killed mice within 10 min. the light microscopy of the histopathological studies revealed that the principal organ affected by this toxin was the lung but the liver and kidneys also showed lesions. the relevance of this lethal activity from e. coli remains to be determine ... | 2002 | 12516774 |
| dna detection and signal amplification via an engineered allosteric enzyme. | rapid, sensitive, and sequence-specific dna detection can be achieved in one step using an engineered intrasterically regulated enzyme. the semi-synthetic inhibitor-dna-enzyme (ide) construct (left) rests in the inactive state but upon exposure to a complementary dna sequence undergoes a dna hybridization-triggered allosteric enzyme activation (right). the ensuing rapid substrate turnover provides the built-in signal amplification mechanism for detecting approximately 10 fmol dna in less than 3 ... | 2003 | 12517141 |
| characterization of an algae-lytic substance secreted by bacillus cereus, an indigenous bacterial isolate from lake kasumigaura. | in order to develop a practical biological strategy for water bloom-control in lake kasumigaura, indigenous algae-lytic bacteria targeting microcystis spp. (the dominant cyanobacteria), was first carried out. some basic lytic characteristics of the isolates concerning the biological and physico-chemical factors in actual water environments were then investigated. fifteen algae-lytic bacteria were successfully isolated using the double layer method. the isolate showing the highest lytic activity ... | 2002 | 12523763 |
| beta-lactamase genes of the penicillin-susceptible bacillus anthracis sterne strain. | susceptibility to penicillin and other beta-lactam-containing compounds is a common trait of bacillus anthracis. beta-lactam agents, particularly penicillin, have been used worldwide to treat anthrax in humans. nonetheless, surveys of clinical and soil-derived strains reveal penicillin g resistance in 2 to 16% of isolates tested. bacterial resistance to beta-lactam agents is often mediated by production of one or more types of beta-lactamases that hydrolyze the beta-lactam ring, inactivating the ... | 2003 | 12533457 |
| vitreous penetration of orally administered gatifloxacin in humans. | to investigate the penetration of gatifloxacin, a novel extended-spectrum fluoroquinolone antibiotic, into the vitreous humor after oral administration. | 2002 | 12545689 |
| [detection of enterotoxin genes in bacillus thuringiensis by pcr]. | the presence of hemolysin hbla (hbla), enterotoxin bcet (bcet) and enterotoxin s (ents) genes from 45 strains of b. thuringiensis, 4 strains of b. cereus and b. sphaericus have been detected respectively by multiple pcr. the results showed that 95.6% b. thuringiensis strains contain the b component of hbla gene, 91.1% and 93.3% of them contain bcet and ents genes sequences respectively. the enterotoxin productions in all strains have also been analysis using two commercial immunoassay kits(tecra ... | 2001 | 12549018 |
| [transcriptional activator plcr regulate the expression of multiple genes in bacillus cereus]. | food-poisoning and some diseases of human can be caused by potential pathogenic factors including phospholipases of c-type, hemolysins, enterotoxins, emetic toxin and others from bacillus cereus which is an opportunistic pathegon. generally, the expression of pathogenic genes is completed by a co-regulation in many bacteria. the isolation of a mutant, displaying significant reducing expression of lecithinase and general proteolytic activities, from a transposon-induced bank of b. cereus type str ... | 2001 | 12549084 |
| [sequencing of a beta-amylase gene from bacillus firmus]. | the gene encoding a beta-amylase from bacillus firmus 725 was sequenced. the sequenced dna of 2012 bp contains one open reading frame of 1406 nucleotides without a translation stop codon. the deduced amino acid sequence homology with those known bacterial and some plant beta-amylase was 98% for bacillus polymyxa 72, 98% for bacillus polymyxa atcc8523, 82% for bacillus circulans, 54% for clostridium thermosulfurogenes, 49% for bacillus cereus bq10-s1, 50% for bacillus cereus var. mycoides, 36% fo ... | 1998 | 12549376 |
| [observations of characteristics of the mechanisms of biological oxidation of cell wall-deficient bacteria]. | the l-forms were induced from staphylococcus aureus, escherichia coli and bacillus cereus by beta-lactam antibiotics and then observations on the properties of oxygen requirement, sugar fermentation and sensitive to cyanide of the l-forms were done. the results were shown that the l-forms derived from the obligate aerobe or the facultative anaerobe did not ferment sugars and were highly oxygen-dependent and more sensitive to cyanide than their parent bacteria. the metabolic activities which were ... | 1998 | 12549407 |
| [studies on the parasites of paris polyphylla var. yunnanensis]. | two bacteria and three fungi were isolated from the hypogeal stems of paris polyphylla var. yunnanensis. the bacteria were identified as bacillus cereus and pseudomonas alcaligenes, and the fungi were identified as periconia sp., pachnocybe albida and hormomyces paridiphilus. the results on liquid culture of b. cereus, p. alcaligenes and h. paridiphilus indicated that the colloidization and polysaccharide content increasing in hypogeal stems of p. polyphylla var. yunnanensis were due to the extr ... | 1999 | 12555422 |
| [purification and characterization of a novel antifungal peptide aps-1 produced by bacillus cereus]. | in previous study, we isolated an antagonist bacillus cereus strain: s-1 from cotton plant. in field experiments, this bacterium was shown strong inhibition to several plant diseases. in this paper, we reported the purification of the antifungal substance produced by the bacterium and its properties. after the steps of acid precipitation, methanol and ethy lether extraction, sephadex g100 and deae52 column chromatography, the antifungal material was purified. the purified material had absorption ... | 1999 | 12555574 |
| degradation of predigested distillery effluent by isolated bacterial strains. | batch studies were conducted on degradation of anaerobically digested distillery wastewater by three bacterial strains, viz. xanthomonas fragariae, bacillus megaterium and bacillus cereus in free and immobilized form, isolated from the activated sludge of a distillery wastewater treatment plant. the removal of cod and colour with all the three strains increased with time up to 48 hr and only marginal increase in cod and colour removal efficiency was observed beyond this period up to 72 hr. after ... | 2002 | 12561978 |
| microbiological quality of take-away cooked rice and chicken sandwiches: effectiveness of food hygiene training of the management. | during august 2001 a microbiological study of ready-to-eat cooked rice from take-aways and of chicken sandwiches made on the premises from sandwich bars was undertaken. the intention was to identify risk factors in the production, storage and handling of cooked rice and sandwiches, and to establish their effect on microbiological quality. examination of cooked rice revealed that the majority of samples (87%; 442 of 508) were of satisfactory/acceptable microbiological quality; 50 (10%) were unsat ... | 2002 | 12564243 |
| active-site mutants of class b beta-lactamases: substrate binding and mechanistic study. | increased resistance to beta-lactam antibiotics is mainly due to beta-lactamases. x-ray structures of zinc beta-lactamases unraveled the coordination of the metal ions, but their mode of action remains unclear. recently, enzymes in which one of the zinc ligands was mutated have been characterized and their catalytic activity against several beta-lactam antibiotics measured. a molecular modeling study of these enzymes was performed here to explain the catalytic activity of the mutants. coordinati ... | 2002 | 12568339 |
| bacteriocins from pediococcus pentosaceus l and s from pork meat. | two strains of pediococcus pentosaceus were isolated from refrigerated pork and found to produce antimicrobial substances that may inhibit foodborne pathogens and have potential as natural food preservatives. they were named p. pentosaceus l and s. the antimicrobial substances were purified to electrophoretical homogeneity by chloroform extraction and designated pentocins l and s with molecular masses (m) of 27 and 25 kda, respectively. both pentocins also had broad inhibition spectra and were t ... | 2003 | 12568574 |
| inactivation of bacteria and spores by pulse electric field and high pressure co2 at low temperature. | the common methods for inactivation of bacteria involve heating or exposure to toxic chemicals. these methods are not suitable for heat-sensitive materials, food, and pharmaceutical products. recently, a complete inactivation of many microorganisms was achieved with high-pressure carbon dioxide at ambient temperature and in the absence of organic solvent and irradiation. the inactivation of spores with co(2) required long residence time and high temperatures, such as 60 degrees c. in this study ... | 2003 | 12569631 |
| cloning, sequencing, and expression of the chitinase gene chia74 from bacillus thuringiensis. | the endochitinase gene chia74 from bacillus thuringiensis serovar kenyae strain lbit-82 was cloned in escherichia coli dh5 alpha f'. a sequence of 676 amino acids was deduced when the gene was completely sequenced. a molecular mass of 74 kda was estimated for the preprotein, which includes a putative 4-kda signal sequence located at the n terminus. the deduced amino acid sequence showed high degree of identity with other chitinases such as chib from bacillus cereus (98%) and chia71 from bacillus ... | 2003 | 12571025 |
| use of a promoter trap to identify bacillus cereus genes regulated by tomato seed exudate and a rhizosphere resident, pseudomonas aureofaciens. | the goal of this study was to identify genes in bacillus cereus, a bacterium commonly associated with plant seeds and roots, that are affected by compounds originating from a host plant, tomato, or another rhizosphere resident, pseudomonas aureofaciens. we constructed a b. cereus chromosomal dna library in a promoter-trap plasmid, pad123, which contains a promoterless version of the green fluorescent protein (gfp) gene, gfpmut3a. the library was screened by using fluorescence-activated cell sort ... | 2003 | 12571047 |
| altering substrate specificity of phosphatidylcholine-preferring phospholipase c of bacillus cereus by random mutagenesis of the headgroup binding site. | plc(bc) is a 28.5 kda monomeric enzyme that catalyzes the hydrolysis of the phosphodiester bond of phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine to provide a diacylglycerol and the corresponding phosphorylated headgroup. because single replacements of glu4, tyr56, and phe66 in the headgroup binding pocket led to changes in substrate specificity [martin et al. (2000) biochemistry 39, 3410-3415], a combinatorial library of approximately 6000 maltose binding protein-plc(bc) ... | 2003 | 12578373 |
| thiols as classical and slow-binding inhibitors of imp-1 and other binuclear metallo-beta-lactamases. | the inhibitory effect of a variety of thiol compounds on the function of binuclear metallo-beta-lactamases, with a particular focus on imp-1 from pseudomonas aeruginosa, has been investigated. thiol inhibitors, depending on their structural features, fall into two categories, one in which inhibition at neutral ph was instantaneous and the other in which inhibition was time-dependent. while mercaptans with anionic substituents in the vicinity of their sh groups exhibited the former type of inhibi ... | 2003 | 12578382 |
| mobility, bioavailability, and toxic effects of cadmium in soil samples. | total concentration is not a reliable indicator of metal mobility or bioavailability in soils. the physicochemical form determines the behavior of metals in soils and hence the toxicity toward terrestrial biota. the main objectives of this study were the application and comparison of three approaches for the evaluation of cadmium behavior in soil samples. the mobility and bioavailability of cadmium in five selected soil samples were evaluated using equilibrium speciation (windermere humic aqueou ... | 2003 | 12584013 |
| use of bioactive glass slides for matrix-assisted laser desorption/ionization analysis: application to microorganisms. | glass slides are widely used in high-throughput analysis and are available commercially with surfaces activated, etched, and channeled. thin glass microscope slides are shown here to be suitable sample supports for matrix-assisted laser desorption/ionization (maldi) mass spectrometry. as a demonstration, lectins immobilized on glass slides with activated surfaces are used to concentrate and purify agglutinated bacillis spores. it is expected that such slides will provide a rapid, inexpensive way ... | 2003 | 12585503 |
| contamination flows of bacillus cereus and spore-forming aerobic bacteria in a cooked, pasteurized and chilled zucchini purée processing line. | a food processing plant producing pasteurized purées and its zucchini purée processing line were examined for contamination with aerobic and facultative anaerobic bacterial spores during a day's operation. multiplication of spores was also monitored in the product stored under different conditions. high concentrations of bacillus cereus spores were found in the soil in which the zucchinis were grown (4.6+/-0.3 log cfu/g), with a background spore population of 6.1+/-0.2 log cfu/g. in the processi ... | 2003 | 12593925 |
| fatal bacillus cereus sepsis following resolving neutropenic enterocolitis during the treatment of acute leukemia. | bacillus cereus is increasingly being acknowledged as a serious bacterial pathogen in immunosuppressed hosts. we report a case of fatal b. cereus sepsis in a patient with newly diagnosed acute leukemia following resolving neutropenic enterocolitis. gastrointestinal complaints are common during induction chemotherapy, yet some antimicrobial coverage suitable for generalized neutropenia is not optimal for the eradication of b. cereus. this case demonstrates that, in the neutropenic patient with ga ... | 2003 | 12605393 |
| vitreous and aqueous penetration of orally administered gatifloxacin in humans. | to investigate the penetration of gatifloxacin, a novel extended-spectrum fourth-generation fluoroquinolone antibiotic, into the vitreous and aqueous humor after oral administration. | 2003 | 12617704 |
| effects of gamma ray and electron-beam irradiations on survival of anaerobic and facultatively anaerobic bacteria. | an extension of the approval for food irradiation is desired due to the increase in the incidence of food poisoning in the world. one anaerobic (clostridium perfringens) and four facultatively anaerobic (bacillus cereus, escherichia coli o157:h7, listeria monocytogenes, and salmonella enteritidis) bacteria irradiated with gamma ray or electron beam (e-beam) were tested in terms of survival on agar under packaging atmosphere. using pouch pack, effects of two irradiations on survival of anaerobic ... | 2002 | 12638185 |
| isolation and characterisation of a novel bacteriocin produced by bacillus thuringiensis strain b439. | bacillus thuringiensis strain b439 produces a bacteriocin-like inhibitory substance in its growth medium. this antimicrobial peptide, referred to as thuricin 439, acts as a bacteriocidal peptide and exhibits an apparent narrow range of inhibitory activity, essentially only affecting growth of bacillus cereus and b. thuringiensis strains. it remains active over a relatively wide ph and temperature range, showing no loss of activity following heat treatments up to 80 degrees c. purification of thu ... | 2003 | 12644238 |
| effect of ultraviolet on the survival of bacteria airborne in simulated martian dust clouds. | a chamber was constructed to create simulated martian dust storms and thereby study the survival of airborne micro-organisms while exposed to the rigors of the martian environment, including ultraviolet irradiation. representative types of sporeforming and non-sporeforming bacteria present in spacecraft assembly areas and indigenous to humans were studied. it was found that daily ultraviolet irradiation of 2 to 9 x 10(7) erg cm-2 was not sufficient to sterilize the dust clouds. the soil particle ... | 1970 | 12664918 |
| coordination geometries of metal ions in d- or l-captopril-inhibited metallo-beta-lactamases. | d- and l-captopril are competitive inhibitors of metallo-beta-lactamases. for the enzymes from bacillus cereus (bcii) and aeromonas hydrophila (cpha), we found that the mononuclear enzymes are the favored targets for inhibition. by combining results from extended x-ray absorption fine structure, perturbed angular correlation of gamma-rays spectroscopy, and a study of metal ion binding, we derived that for cd(ii)1-bcii, the thiolate sulfur of d-captopril binds to the metal ion located at the site ... | 2003 | 12668674 |
| methionine regeneration and aminotransferases in bacillus subtilis, bacillus cereus, and bacillus anthracis. | the conversion of ketomethiobutyrate to methionine has been previously examined in a number of organisms, wherein the aminotransferases responsible for the reaction have been found to be members of the ia subfamily (l. c. berger, j. wilson, p. wood, and b. j. berger, j. bacteriol. 183:4421-4434, 2001). the genome of bacillus subtilis has been found to contain no subfamily ia aminotransferase sequences. instead, the analogous enzymes in b. subtilis were found to be members of the if subfamily. th ... | 2003 | 12670965 |
| probiotic and milk technological properties of lactobacillus brevis. | two lactobacillus brevis strains atcc 8287 and atcc 14869(t), were evaluated for their applicability as putative probiotics in dairy products. the strains expressed good in vitro adherence to human caco-2 and intestine 407 cells and tolerated well low ph, bile acids and pancreatic fluid under in vitro conditions. in antimicrobial activity assays, strain atcc 8287 showed inhibitory properties toward selected potential harmful microorganisms, particularly against bacillus cereus. both l. brevis st ... | 2003 | 12672593 |
| rope-producing strains of bacillus spp. from wheat bread and strategy for their control by lactic acid bacteria. | two types of white wheat bread (high- and low-type loaves) were investigated for rope spoilage. thirty of the 56 breads tested developed rope spoilage within 5 days; the high-type loaves were affected by rope spoilage more than the low-type loaves. sixty-one bacillus strains were isolated from ropy breads and were characterized on the basis of their phenotypic and genotypic traits. all of the isolates were identified as bacillus subtilis by biochemical tests, but molecular assays (randomly ampli ... | 2003 | 12676716 |
| production of diarrheal enterotoxins and other potential virulence factors by veterinary isolates of bacillus species associated with nongastrointestinal infections. | with the exceptions of bacillus cereus and bacillus anthracis, bacillus species are generally perceived to be inconsequential. however, the relevance of other bacillus species as food poisoning organisms and etiological agents in nongastrointestinal infections is being increasingly recognized. eleven bacillus species isolated from veterinary samples associated with severe nongastrointestinal infections were assessed for the presence and expression of diarrheagenic enterotoxins and other potentia ... | 2003 | 12676723 |
| detection of anthrax simulants with microcalorimetric spectroscopy: bacillus subtilis and bacillus cereus spores. | recent advances in the development of ultrasensitive micromechnical thermal detectors have led to the advent of novel subfemtojoule microcalorimetric spectoscopy (calspec). on the basis of principles of photothermal ir spectroscopy combined with efficient thermomechanical transduction, calspec provides acquisition of vibrational spectra of microscopic samples and absorbates. we use calspec as a method of identifying nanogram quantities of biological micro-organisms. our studies focus on bacillus ... | 2003 | 12683752 |
| demonstration of a hermetic airborne ozone disinfection system: studies on e. coli. | an enclosed flow-through system using airborne ozone for disinfection and which removes the ozone with a catalytic converter was tested with a strain of escherichia coli. petri dishes containing the microorganisms were inserted in a chamber and exposed for 10-480 min to ozone concentrations between 4 and 20 ppm. death rates in excess of 99.99% were achieved. survival data is fitted to a two-stage curve with a shoulder based on the multihit target model. ozone was removed from the exhaust air to ... | 2003 | 12688846 |
| inactivation of bacillus cereus spores by high hydrostatic pressure at different temperatures. | the effect of ph on the initiation of germination and on the inactivation of bacillus cereus (kctc 1012) spores during high hydrostatic pressure processing (hpp) with pressures of 0.1 to 600 mpa at different temperatures was investigated. two different high-pressure treatments were adopted to evaluate the effect of ph on the inactivation of b. cereus on sporulation medium and in suspension medium. inactivation of b. cereus spores with hpp treatment was affected more by sporulation medium ph than ... | 2003 | 12696682 |
| a retail and consumer phase model for exposure assessment of bacillus cereus. | an exposure assessment is conducted for psychrotrophic and mesophilic bacillus cereus in a cooked chilled vegetable product. a model is constructed that covers the retail and consumer phase of the food pathway, using the output of a similar model on the industrial process as input. microbial growth is the predominant process in the model. variability in time and temperature during transport and storage is included in the model and different domestic refrigerator temperature distributions are com ... | 2003 | 12706041 |
| demonstration of labeless detection of food pathogens using electrochemical redox probe and screen printed gold electrodes. | the demonstration of a labeless immunosensor for the detection of pathogenic bacteria using screen printed gold electrodes (spges) and a potassium hexacyanoferrate(ii) redox probe is reported. gold electrodes were produced using screen printing and the gold surfaces were modified by a thiol based self assembled monolayer (sam) to facilitate antibody immobilisation. sams based on the use of thioctic acid (ta), mercaptopropionic acid (mpa) and mercaptoundecanoic acid (mua) were evaluated. followin ... | 2003 | 12713911 |
| ym-266183 and ym-266184, novel thiopeptide antibiotics produced by bacillus cereus isolated from a marine sponge. i. taxonomy, fermentation, isolation, physico-chemical properties and biological properties. | novel antibiotics, ym-266183 (1) and ym-266184 (2), were found in the culture broth of bacillus cereus qn03323 which was isolated from the marine sponge halichondria japonica. the structures of both antibiotics were determined by several spectroscopic experiments as new thiopeptide compounds. they exhibited potent antibacterial activities against staphylococci and enterococci including multiple drug resistant strains, whereas they were inactive against gram-negative bacteria. | 2003 | 12715871 |
| ym-266183 and ym-266184, novel thiopeptide antibiotics produced by bacillus cereus isolated from a marine sponge ii. structure elucidation. | ym-266183 and ym-266184 are new antibacterial substances that have activity against drug-resistant bacteria produced by bacillus cereus qn03323. these structures were elucidated by ms and nmr spectral analysis. ym-266183 and ym-266184 are the cyclic thiopeptides containing thiazole and pyridine moieties, and several unusual amino acids. | 2003 | 12715872 |
| allosteric interactions within subsites of a monomeric enzyme: kinetics of fluorogenic substrates of pi-specific phospholipase c. | two novel water-soluble fluorescein myo-inositol phosphate (flip) substrates, butyl-flip and methyl-flip, were used to examine the kinetics and subsite interactions of bacillus cereus phosphatidylinositol-specific phospholipase c. butyl-flip exhibited sigmoidal kinetics when initial rates are plotted versus substrate concentration. the data fit a hill coefficient of 1.2-1.5, suggesting an allosteric interaction between two sites. two substrate molecules bind to this enzyme, one at the active sit ... | 2003 | 12719256 |
| genomics: relative pathogenic values. | | 2003 | 12721608 |
| the genome sequence of bacillus anthracis ames and comparison to closely related bacteria. | bacillus anthracis is an endospore-forming bacterium that causes inhalational anthrax. key virulence genes are found on plasmids (extra-chromosomal, circular, double-stranded dna molecules) pxo1 (ref. 2) and pxo2 (ref. 3). to identify additional genes that might contribute to virulence, we analysed the complete sequence of the chromosome of b. anthracis ames (about 5.23 megabases). we found several chromosomally encoded proteins that may contribute to pathogenicity--including haemolysins, phosph ... | 2003 | 12721629 |
| genome sequence of bacillus cereus and comparative analysis with bacillus anthracis. | bacillus cereus is an opportunistic pathogen causing food poisoning manifested by diarrhoeal or emetic syndromes. it is closely related to the animal and human pathogen bacillus anthracis and the insect pathogen bacillus thuringiensis, the former being used as a biological weapon and the latter as a pesticide. b. anthracis and b. thuringiensis are readily distinguished from b. cereus by the presence of plasmid-borne specific toxins (b. anthracis and b. thuringiensis) and capsule (b. anthracis). ... | 2003 | 12721630 |
| regioselective glucosylation of pyridoxine by microorganisms. | microorganisms from culture collections and isolates from nature were screened for the ability to catalyze the regioselective glucosylation of pyridoxine (pn) to produce pyridoxine 5'-alpha-d-glucoside (pn-5'-alpha-g) or pyridoxine 4'-alpha-d-glucoside (pn-4'-alpha-g). transglucosylation activity specific to 5'-position of pn was found in fungi belonging to genera such as coriolus and verticillium, and activity at the 4'-position of pn was found in bacteria belonging to genera such as bacillus a ... | 2003 | 12723596 |
| the inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding. | thiomandelic acid is a simple, broad spectrum, and reasonably potent inhibitor of metallo-beta-lactamases, enzymes that mediate resistance to beta-lactam antibiotics. we report studies by nmr and perturbed angular correlation (pac) spectroscopy of the mode of binding of the r and s enantiomers of thiomandelic acid, focusing on their interaction with the two metal ions in cadmium-substituted bacillus cereus metallo-beta-lactamase. the 113cd resonances are specifically assigned to the metals in th ... | 2003 | 12724330 |
| genome differences that distinguish bacillus anthracis from bacillus cereus and bacillus thuringiensis. | the three species of the group 1 bacilli, bacillus anthracis, b. cereus, and b. thuringiensis, are genetically very closely related. all inhabit soil habitats but exhibit different phenotypes. b. anthracis is the causative agent of anthrax and is phylogenetically monomorphic, while b. cereus and b. thuringiensis are genetically more diverse. an amplified fragment length polymorphism analysis described here demonstrates genetic diversity among a collection of non-anthrax-causing bacillus species, ... | 2003 | 12732546 |
| a mammalian cell regulatory agent, ceres-18, inhibits yeast cell proliferation but not bacterial replication. | a cell regulatory sialoglycopeptide, ceres-18, purified from intact bovine cerebral cortex cells, has exhibited the capability of reversibly inhibiting cellular dna synthesis and the proliferation of a wide array of mammalian cells. in the present study, the effect of ceres-18 on the proliferation of bacterial ( bacillus cereus and escherichia coli) and yeast ( saccharomyces cerevisiae and schizosaccharomyces pombe) cells was investigated. the results showed that replication and viability of the ... | 2003 | 12732963 |
| crystal structure of a catalytic site mutant of beta-amylase from bacillus cereus var. mycoides cocrystallized with maltopentaose. | the x-ray crystal structure of a catalytic site mutant of beta-amylase, e172a (glu172 --> ala), from bacillus cereus var. mycoides complexed with a substrate, maltopentaose (g5), and the wild-type enzyme complexed with maltose were determined at 2.1 and 2.0 a resolution, respectively. clear and continuous density corresponding to g5 was observed in the active site of e172a, and thus, the substrate, g5, was not hydrolyzed. all glucose residues adopted a relaxed (4)c(1) conformation, and the confo ... | 2003 | 12741813 |
| the microbiological quality of ready-to-eat foods with added spices. | a microbiological study of ready-to-eat foods with added spices or spice ingredients was undertaken to identify any risk factors in the production, storage and display of this product and to establish their effect on microbiological quality. examination of 1946 ready-to-eat foods from sandwich bars, cafés, public houses, restaurants, specialist sandwich producers, bakers, delicatessens, market stalls and mobile vendors found that 1291 (66%) were of satisfactory/acceptable microbiological quality ... | 2003 | 12745346 |
| bacillus thuringiensis associated with faeces of the kerama-jika, cervus nippon keramae, a wild deer indigenous to the ryukyus, japan. | faeces of the kerama-jika (cervus nippon keramae), a wild shika deer indigenous to the ryukyus, japan, were examined for the natural occurrence of bacillus thuringiensis. of the ten faecal samples tested, seven contained this organism. the frequency of b. thuringiensis was 8.5% among 387 colonies of spore-forming bacteria belonging to the bacillus cereus/b. thuringiensis group. of 33 b. thuringiensis isolates recovered, only one isolate, assigned to the serotype h3abc (serovar kurstaki), exhibit ... | 2003 | 12746858 |
| the patchwork nature of rolling-circle plasmids: comparison of six plasmids from two distinct bacillus thuringiensis serotypes. | bacillus thuringiensis, the entomopathogenic bacteria from the bacillus cereus group, harbors numerous extrachromosomal molecules whose sizes vary from 2 to more than 200kb. apart from the genes coding for the biopesticide delta-endotoxins located on large plasmids, little information has been obtained on these plasmids and their contribution to the biology of their host. in this paper, we embarked on a detailed comparison of six small rolling-circle replicating (rcr) plasmids originating from t ... | 2003 | 12749835 |
| [production of oil-processing compounds by microorganisms from the daqing oil field, china]. | twenty pure cultures isolated from formation waters of the daqing oil field were studied with respect to their capacity to produce surface-active compounds in media with individual hydrocarbons, lower alcohols, and fatty acids. aerobic saprotrophic bacteria belonging to the genera bacillus, brevibacillus, rhodococcus, dietzia, kocuria, gordonia, cellulomonas, clavibacter, pseudomonas, and acinetobacter decreased the surface tension of cultivation media from 55-63 to 28-44 mn/m. strains of bacill ... | 2003 | 12751245 |
| genetic relationship in the 'bacillus cereus group' by rep-pcr fingerprinting and sequencing of a bacillus anthracis-specific rep-pcr fragment. | to evaluate the genetic relationship in the bacillus cereus group by rep-pcr fingerprinting. | 2003 | 12752821 |
| genes of bacillus cereus and bacillus anthracis encoding proteins of the exosporium. | the exosporium is the outermost layer of spores of bacillus cereus and its close relatives bacillus anthracis and bacillus thuringiensis. for these pathogens, it represents the surface layer that makes initial contact with the host. to date, only the bcla glycoprotein has been described as a component of the exosporium; this paper defines 10 more tightly associated proteins from the exosporium of b. cereus atcc 10876, identified by n-terminal sequencing of proteins from purified, washed exospori ... | 2003 | 12754235 |
| relationship of plcr-regulated factors to bacillus endophthalmitis virulence. | the explosive, destructive course of bacillus endophthalmitis has been attributed to the production of toxins during infection. in this study we analyzed the contribution of toxins controlled by the global regulator plcr to the pathogenesis of experimental bacillus endophthalmitis. isogenic plcr-deficient mutants of bacillus cereus and bacillus thuringiensis were constructed by insertional inactivation of plcr by the kanamycin resistance cassette, apha3. rabbit eyes were injected intravitreally ... | 2003 | 12761089 |
| glu-53 of bacillus cereus sphingomyelinase acts as an indispensable ligand of mg2+ essential for catalytic activity. | bacillus cereus sphingomyelinase (smase) is an extracellular hemolysin classified into a group of mg(2+)-dependent neutral smases (nsmase). sequence comparison of bacterial and eukaryotic mg(2+)-dependent nsmases has shown that several amino acid residues, including glu-53 of b. cereus smase, are conserved, suggesting a catalytic mechanism common to these enzymes. mutational analysis has revealed that hemolytic and sm-hydrolyzing activities are abolished by e53a and e53q mutations. only the e53d ... | 2003 | 12761162 |
| crystal structures of beta-amylase from bacillus cereus var mycoides in complexes with substrate analogs and affinity-labeling reagents. | the crystal structures of beta-amylase from bacillus cereus var. mycoides in complexes with five inhibitors were solved. the inhibitors used were three substrate analogs, i.e. glucose, maltose (product), and a synthesized compound, o-alpha-d-glucopyranosyl-(1-->4)-o-alpha-d-glucopyranosyl-(1-->4)-d-xylopyranose (ggx), and two affinity-labeling reagents with an epoxy alkyl group at the reducing end of glucose. for all inhibitors, one molecule was bound at the active site cleft and the non-reducin ... | 2003 | 12761294 |
| methodologies for the characterization of microbes in industrial environments: a review. | there is growing interest in research and development to develop novel tools to study, detect, and characterize microbes and their communities in industrial environments. however, knowledge about their validity in practical industrial use is still scarce. this review describes the advantages and limitations of traditional and molecular methods used for biofilm and/or planktonic cell studies, especially those performed with listeria monocytogenes, bacillus cereus, and/or clostridium perfringens. ... | 2003 | 12764674 |
| phospholipase activity on n-acyl phosphatidylethanolamines is critically dependent on the n-acyl chain length. | we have recently shown that an endogenous phospholipase a2 from bovine erythrocytes does not hydrolyse napes (n-acyl l-alpha-phosphatidylethanolamines), which accumulate remarkably in this system [florin-christensen, suarez, florin-christensen, wainszelbaum, brown, mcelwain and palmer (2001) proc. natl. acad. sci. u.s.a. 98, 7736-7741]. here we investigate the causes underlying this resistance. n-acylation of pe (l-alpha-phosphatidylethanolamine) results in alteration of charge, head-group volum ... | 2003 | 12765548 |
| carbohydrates and glycoproteins of bacillus anthracis and related bacilli: targets for biodetection. | the spore is the form released in a bioterrorism attack. there is a real need for definition of new targets for bacillus anthracis that might be incorporated into emerging biodetection technologies. particularly of interest are macromolecules found in b. anthracis that are (1) spore-specific, (2) readily accessible on the spore surface and (3) distinct from those present in related organisms. one of the few biochemical methods to identify the spores of b. anthracis is based on the presence of rh ... | 2003 | 12782370 |
| fluorescent heteroduplex assay for monitoring bacillus anthracis and close relatives in environmental samples. | a fluorescent heteroduplex method was developed to assess the presence of 16s rrna gene (rdna) sequences from bacillus anthracis and close relatives in pcr-amplified 16s rdna sequence mixtures from environmental samples. the method uses a single-stranded, fluorescent dna probe, 464 nucleotides in length, derived from a b. anthracis 16s rrna gene. the probe contains a unique, engineered deletion such that all probe-target duplexes are heteroduplexes with an unpaired g at position 343 (deltag343). ... | 2003 | 12788732 |
| intestinal perforations in a premature infant caused by bacillus cereus. | although bacillus cereus is a ubiquitous bacterium, the incidence of neonatal infections is very low with only a few cases of b. cereus infections in neonates reported in the literature. we report the case of a premature infant with multiple intestinal perforations and an abdominal b. cereus infection. the initial course was characterized by severe cardiovascular shock, anemia, thrombocytopenia and disseminated intravascular coagulation, leading to periventricular leukomalacia, alopecia capitis ... | 2003 | 12789482 |
| chemical composition and antibacterial activity of essential oils from thymus spinulosus ten. (lamiaceae). | the chemical composition of essential oils from aerial parts of thymus spinulosus ten. (lamiaceae) is reported. four oils from plants growing in different environmental conditions were characterized by gc and gc-ms methods; the oils seem to indicate a new chemotype in the genus thymus. influences of soil and altitude characteristics on the essential oil composition are discussed. the oils showed antibacterial activity against gram-positive (staphylococcus aureus, streptococcus faecalis, bacillus ... | 2003 | 12797754 |
| the bacillus cereus bcet enterotoxin sequence reappraised. | bacillus cereus is a known opportunistic human pathogen belonging to the b. cereus group. establishment of the pathogenesis most likely involves several gene products. one of these gene products, a single gene component named bcet, has been cloned and described from b. cereus b-4ac [agata et al., microbiology 141 (1995) 983-988]. however, our sequences of the bcet region from 16 b. cereus group strains showed inconsistency with the published bcet sequence. only part of the bcet sequence had homo ... | 2003 | 12798995 |
| improved model based on the weibull distribution to describe the combined effect of ph and temperature on the heat resistance of bacillus cereus in carrot juice. | the effect of ph and temperature on the thermal inactivation of different strains of bacillus cereus was modeled. inactivation tests were carried out in carrot broth, following a full factorial design at four levels for temperature (from 90 to 105 degrees c, depending on the strain) and ph (6.2, 5.8, 5.2, and 4.7). individual inactivation curves were analyzed by applying the weibull model function (with percent discrepancy close to 20% for most cases), and the effects of ph and temperature on th ... | 2003 | 12800997 |
| potential of bacillus cereus for producing an emetic toxin, cereulide, in bakery products: quantitative analysis by chemical and biological methods. | a method for the direct quantitative analysis of cereulide, the emetic toxin of bacillus cereus, in bakery products was developed. the analysis was based on robotized extraction followed by quantitation of cereulide by liquid chromatography-mass spectrometry and an assay of toxicity by the boar sperm motility inhibition test. the bioassay and the chemical assay gave comparable results, demonstrating that the extracted cereulide was in a biologically active form. cereulide was formed when cereuli ... | 2003 | 12801008 |
| antimicrobial properties of commercial annatto extracts against selected pathogenic, lactic acid, and spoilage microorganisms. | annatto preparations are used to impart distinctive flavor and color to foods and are a primary colorant in dairy foods such as cheese and butter. there are several reports indicating that certain fractions of the annatto plant have biological activities against microorganisms of significance in food fermentation, food preservation, and human health. however, little is reported describing the nature of the antimicrobial compound(s) or their potential presence in commercial annatto colorant prepa ... | 2003 | 12801012 |
| detection and differentiation of biological species using microcalorimetric spectroscopy. | we report on the application of infrared (ir) microcalorimetric spectroscopy ( micro -calspec) to the identification and detection of trace amounts of biological species. our approach combines principles of photothermal ir spectroscopy with ultrasensitive microcantilever (mc) thermal detectors. we have obtained photothermal ir spectra for dna and rna bases and for bacillus cereus (an anthrax simulant) in the wavelength range of 2.5-14.5 micro m (4000-690 cm(-1)). the measurements are accomplishe ... | 2003 | 12801702 |
| bacteriocidal effects and inhibition of cell separation of cinnamic aldehyde on bacillus cereus. | in this study, bacteriocidal effects of cinnamic aldehyde on bacillus cereus were investigated. | 2003 | 12803558 |
| a novel double heme substitution produces a functional bo3 variant of the quinol oxidase aa3 of bacillus cereus. purification and paratial characterization. | a novel bo3-type quinol oxidase was highly purified from bacillus cereus pym1, a spontaneous mutant unable to synthesize heme a and therefore spectroscopically detectable cytochromes aa3 and caa3. the purified enzyme contained 12.4 nmol of heme o and 11.5 nmol of heme b mg-1 protein. the enzyme was composed of two subunits with an mr of 51,000 and 30,000, respectively. both subunits were immunoreactive to antibodies raised against the b cereus aa3 oxidase. moreover, amino-terminal sequence analy ... | 2003 | 12805383 |
| phylogenetic relationships between bacillus species and related genera inferred from comparison of 3' end 16s rdna and 5' end 16s-23s its nucleotide sequences. | the nucleotide sequences of the 3' end of the 16s rdna and the 16s-23s internal transcribed spacer (its) of 40 bacillaceae species were determined. these included 21 bacillus, 9 paenibacillus, 6 brevibacillus, 2 geobacillus, 1 marinibacillus and 1 virgibacillus species. comparative sequence analysis of a 220 bp region covering a highly conserved 150 bp sequence located at the 3' end of the 16s rrna coding region and a conserved 70 bp sequence located at the 5' end of the 16s-23s its of the 40 sp ... | 2003 | 12807189 |