Properties and Origin of Filamentous Appendages on Spores of <i>Bacillus cereus</i>

Kozuka, Satoshi; Tochikubo, Kunio

doi:10.1111/j.1348-0421.1985.tb00799.x

Cited by 43 publications

(30 citation statements)

References 26 publications

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“…We also note that all the selected isolates were capable of efficient sporulation under laboratory conditions, and their spores conformed to the general structural organization described for Bacillus species (20 (15,28). The hair-like layer at the edge of the spores of isolate 259 is particularly intriguing due to the high similarity observed between the coat polypeptide composition of this isolate and Enterogermina, as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (data not shown).…”

Section: Discussionmentioning

confidence: 90%

Screening for Bacillus Isolates in the Broiler Gastrointestinal Tract

Barbosa

Serra

Ragione

et al. 2005

Appl Environ Microbiol

343

247

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Spores from a number of different Bacillus species are currently being used as human and animal probiotics, although their mechanisms of action remain poorly understood. Here we describe the isolation of 237 presumptive gut-associated Bacillus spp. isolates that were obtained by heat and ethanol treatment of fecal material from organically reared broilers followed by aerobic plating. Thirty-one representative isolates were characterized according to their morphological, physiological, and biochemical properties as well as partial 16S rRNA gene sequences and screening for the presence of plasmid DNA. The Bacillus species identified included B. subtilis, B. pumilus, B. licheniformis, B. clausii, B. megaterium, B. firmus, and species of the B. cereus group, whereas a number of our isolates could not be classified. Intrinsic properties of potential importance for survival in the gut that could be advantageous for spore-forming probiotics were further investigated for seven isolates belonging to five different species. All isolates sporulated efficiently in the laboratory, and the resulting spores were tolerant to simulated gastrointestinal tract conditions. They also exhibited antimicrobial activity against a broad spectrum of bacteria, including food spoilage and pathogenic organisms such as Bacillus spp., Clostridium perfringens, Staphylococcus aureus, and Listeria monocytogenes. Importantly, the isolates were susceptible to most of the antibiotics tested, arguing that they would not act as donors for resistance determinants if introduced in the form of probiotic preparations. Together, our results suggest that some of the sporeformers isolated in this study have the potential to persist in or transiently associate with the complex gut ecosystem.The widespread use of antibiotics as therapeutic and prophylactic agents and as growth promoters in animal husbandry has led to a worldwide increase in antibiotic resistance and the emergence of untreatable multidrug-resistant strains of bacteria (4, 33). This has prompted the European Union to phase out the use of these compounds as animal feed additives by 2006 (47). The use of competitive exclusion agents and probiotic feed additives in the livestock industry is therefore attracting increased attention as a cost-effective alternative to controlling animal disease and improving breeding performance (54).The genus Bacillus comprises a diverse collection of aerobic endospore-forming bacteria whose spores consist of several protective layers surrounding the nucleoid in the spore core (20, 51). This structural organization makes the spores extremely resistant to external physical and chemical insults and in part determines their exceptional longevity in the environment (20, 38). The resilient and ubiquitous nature of these bacteria results in considerable daily intake of these organisms by humans and animals. This ingestion, which is often in the form of spores, occurs primarily through contaminated food and water.Bacillus spores are being used as human and animal probiotics...

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Section: Discussionmentioning

confidence: 90%

Screening for Bacillus Isolates in the Broiler Gastrointestinal Tract

Barbosa

Serra

Ragione

et al. 2005

Appl Environ Microbiol

343

247

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“…Different bacteria and different life cycle stages of bacteria differ in morphology and physiology and express different cell surface structures. The largest difference between B. cereus and B. subtilis is the spores; B. cereus spores are very hydrophobic compared to B. subtilis spores due to appendages on the surface (24,49). This difference is also reflected in differences in frequency and dissipation shifts (Fig.…”

Section: Discussionmentioning

confidence: 99%

“…Good spore yields for both strains (93 to 97%) were obtained. Spores of B. cereus have appendages on the surface (24,49).…”

Section: Methodsmentioning

confidence: 99%

Use of a Quartz Crystal Microbalance To Investigate the Antiadhesive Potential of N -Acetyl- l -Cysteine

Olofsson

Hermansson

Elwing

2005

Appl Environ Microbiol

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The reduction of bacterial biofilm formation on stainless steel surfaces by N-acetyl-L-cysteine (NAC) is attributed to effects on bacterial growth and polysaccharide production, as well as an increase in the wettability of steel surfaces. In this report, we show that NAC-coated stainless steel and polystyrene surfaces affect both the initial adhesion of Bacillus cereus and Bacillus subtilis and the viscoelastic properties of the interaction between the adhered bacteria and the surface. A quartz crystal microbalance with dissipation was shown to be a powerful and sensitive technique for investigating changes in the applied NAC coating for initial cell surface interactions of bacteria. The kinetics of frequency and dissipation shifts were dependent on the bacteria, the life cycle stage of the bacteria, and the surface. We found that exponentially grown cells gave rise to a positive frequency shift as long as their cell surface hydrophobicity was zero. Furthermore, when the characteristics of binding between the cell and the surface for different growth phases were compared, the rigidity increased from exponentially grown cells to starved cells. There was a trend in which an increase in the viscoelastic properties of the interaction, caused by the NAC coating on stainless steel, resulted in a reduction in irreversibly adhered cells. Interestingly, for B. cereus that adhered to polystyrene, the viscoelastic properties decreased, while there was a reduction in adhered cells, regardless of the life cycle stage. Altogether, NAC coating on surfaces was often effective and could both decrease the initial adhesion and increase the detachment of adhered cells and spores. The most effective reduction was found for B. cereus spores, for which the decrease was caused by a combination of these two parameters.Bacteria commonly adhere to a surface and are part of a complex biofilm. Since the growth of biofilms causes enormous economic losses and health problems in industrial systems like food and paper production, huge efforts are made to solve this problem. The adhesion of bacteria to surfaces is a complex interplay of physical, chemical, and biological factors (5), and there are large variations in the adhesion behaviors of different bacteria and also for different life cycle stages of one strain (41). It is very important to consider these differences when antiadhesion coatings are developed. It is generally thought that bacterial adhesion is preceded by the adsorption of a conditioning layer of molecules that influence adhesion of bacteria to surfaces (43). A good antiadhesion coating should form a conditioning film that prevents adhesion and has a low cohesive strength, making a weak bond between the biofilm and the surface (6). One such agent may be N-acetyl-L-cysteine (NAC). NAC is commonly used in medical treatment of chronic bronchitis and cancer (38,46) and is one of the smallest drug molecules in use (30). Moreover, we recently demonstrated that NAC affects several processes that are important for bacterial biofilm fo...

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“…Scanning electron microscopy has revealed a paracrystalline basal layer, with hexagonal periodicity, and a hairlike outer layer (3,11). There are also pilus-like structures on the surface (15). The exosporium contains protein, lipid, and carbohydrate (43 to 52, 15 to 18, and 23% of dry weight, respectively [3,19]).…”

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confidence: 99%

Genes of Bacillus cereus and Bacillus anthracis Encoding Proteins of the Exosporium

et al. 2003

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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 exosporium. Likely coding sequences were identified from the incomplete genome sequence of B. anthracis or B. cereus ATCC 14579, and the precise corresponding sequence from B. cereus ATCC 10876 was defined by PCR and sequencing. Eight genes encode likely structural components (exsB, exsC, exsD, exsE, exsF, exsG, exsJ, and cotE). Several proteins of the exosporium are related to morphogenetic and outer spore coat proteins of B. subtilis, but most do not have homologues in B. subtilis. ExsE is processed from a larger precursor, and the CotE homologue appears to have been C-terminally truncated. ExsJ contains a domain of GXX collagen-like repeats, like the BclA exosporium protein of B. anthracis. Although most of the exosporium genes are scattered on the genome, bclA and exsF are clustered in a region flanking the rhamnose biosynthesis operon; rhamnose is part of the sugar moiety of spore glycoproteins. Two enzymes, alanine racemase and nucleoside hydrolase, are tightly adsorbed to the exosporium layer; they could metabolize small molecule germinants and may reduce the sensitivity of spores to these, limiting premature germination.Spores of the Bacillus cereus family, which includes Bacillus anthracis and Bacillus thuringiensis, all possess a loose balloonlike exosporium (7). A similar layer is also found on spores of some other bacilli and clostridia. The particular adherence and hydrophobic properties conferred by the exosporium (4, 14) suggest that it may possibly be of significance to spore pathogenicity. Bacillus subtilis, the paradigm of sporeformers, has no such clearly defined exosporial layer, so the exosporium has not been studied in molecular detail. Scanning electron microscopy has revealed a paracrystalline basal layer, with hexagonal periodicity, and a hairlike outer layer (3, 11). There are also pilus-like structures on the surface (15). The exosporium contains protein, lipid, and carbohydrate (43 to 52, 15 to 18, and 23% of dry weight, respectively [3,19]). A spore glycoprotein of B. thuringiensis was purified and partially characterized (10); it was present as two forms according to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)-a 70-kDa monomer and a 205-kDa multimer. Another glycoprotein, BclA, important to the surface hairlike layer, has recently been identified in the B. anthracis exosporium (22). Crude exosporium extracts of B. cereus (5) contain at least 12 major and some minor protein components that can be readily solubilized, including GroEL and a zinc metalloprotease called immune inh...

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Properties and Origin of Filamentous Appendages on Spores of Bacillus cereus

Cited by 43 publications

References 26 publications

Screening for Bacillus Isolates in the Broiler Gastrointestinal Tract

Screening for Bacillus Isolates in the Broiler Gastrointestinal Tract

Use of a Quartz Crystal Microbalance To Investigate the Antiadhesive Potential of N -Acetyl- l -Cysteine

Genes of Bacillus cereus and Bacillus anthracis Encoding Proteins of the Exosporium

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