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Anthracis Spores (anthraci + spore)
Kinds of Anthracis Spores Selected AbstractsEarly events of Bacillus anthracis germination identified by time-course quantitative proteomicsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 19 2006Pratik Jagtap Abstract Germination of Bacillus anthracis spores involves rehydration of the spore interior and rapid degradation of several of the protective layers, including the spore coat. Here, we examine the temporal changes that occur during B. anthracis spore germination using an isobaric tagging system. Over the course of 17,min from the onset of germination, the levels of at least 19 spore proteins significantly decrease. Included are acid-soluble proteins, several known and predicted coat proteins, and proteins of unknown function. Over half of these proteins are small (less than 100 amino acids) and would have been undetectable by conventional gel-based analysis. We also identified 20 proteins, whose levels modestly increased at the later time points when metabolism has likely resumed. Taken together, our data show that isobaric labeling of complex mixtures is particularly effective for temporal studies. Furthermore, we describe a rigorous statistical approach to define relevant changes that takes into account the nature of data obtained from multidimensional protein identification technology coupled with the use of isobaric tags. This study provides an expanded list of the proteins that may be involved in germination of the B. anthracis spore and their relative levels during germination. [source] Murine splenocytes produce inflammatory cytokines in a MyD88-dependent response to Bacillus anthracis sporesCELLULAR MICROBIOLOGY, Issue 2 2007Ian J. Glomski Summary Bacillus anthracis is a sporulating Gram-positive bacterium that causes the disease anthrax. The highly stable spore is the infectious form of the bacterium that first interacts with the prospective host, and thus the interaction between the host and spore is vital to the development of disease. We focused our study on the response of murine splenocytes to the B. anthracis spore by using paraformaldehyde-inactivated spores (FIS), a treatment that prevents germination and production of products associated with vegetative bacilli. We found that murine splenocytes produce IL-12 and IFN-, in response to FIS. The IL-12 was secreted by CD11b cells, which functioned to induce the production of IFN-, by CD49b (DX5) NK cells. The production of these cytokines by splenocytes was not dependent on TLR2, TLR4, TLR9, Nod1, or Nod2; however, it was dependent on the signalling adapter protein MyD88. Unlike splenocytes, Nod1- and Nod2-transfected HEK cells were activated by FIS. Both IL-12 and IFN-, secretion were inhibited by treatment with B. anthracis lethal toxin. These observations suggest that the innate immune system recognizes spores with a MyD88-dependent receptor (or receptors) and responds by secreting inflammatory cytokines, which may ultimately aid in resisting infection. [source] Large-Area Silver-Coated Silicon Nanowire Arrays for Molecular Sensing Using Surface-Enhanced Raman Spectroscopy,ADVANCED FUNCTIONAL MATERIALS, Issue 16 2008Baohua Zhang Abstract A new and facile method to prepare large-area silver-coated silicon nanowire arrays for surface-enhanced Raman spectroscopy (SERS)-based sensing is introduced. High-quality silicon nanowire arrays are prepared by a chemical etching method and used as a template for the generation of SERS-active silver-coated silicon nanowire arrays. The morphologies of the silicon nanowire arrays and the type of silver-plating solution are two key factors determining the magnitude of SERS signal enhancement and the sensitivity of detection; they are investigated in detail for the purpose of optimization. The optimized silver-coated silicon nanowire arrays exhibit great potential for ultrasensitive molecular sensing in terms of high SERS signal enhancement ability, good stability, and reproducibility. Their further applications in rapidly detecting molecules relating to human health and safety are discussed. A 10 s data acquisition time is capable of achieving a limit of detection of approximately 4,×,10,6M calcium dipicolinate (CaDPA), a biomarker for anthrax. This value is 1/15 the infectious dose of spores (6,×,10,5,M required), revealing that the optimized silver-coated silicon nanowire arrays as SERS-based ultrasensitive sensors are extremely suitable for detecting Bacillus anthracis spores. [source] Difference between the spore sizes of Bacillus anthracis and other Bacillus speciesJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2007M. Carrera Abstract Aims:, To determine the size distribution of the spores of Bacillus anthracis, and compare its size with other Bacillus species grown and sporulated under similar conditions. Methods and Results:, Spores from several Bacillus species, including seven strains of B. anthracis and six close neighbours, were prepared and studied using identical media, protocols and instruments. Here, we report the spore length and diameter distributions, as determined by transmission electron microscopy (TEM). We calculated the aspect ratio and volume of each spore. All the studied strains of B. anthracis had similar diameter (mean range between 0·81 ± 0·08 ,m and 0·86 ± 0·08 ,m). The mean lengths of the spores from different B. anthracis strains fell into two significantly different groups: one with mean spore lengths 1·26 ± 0·13 ,m or shorter, and another group of strains with mean spore lengths between 1·49 and 1·67 ,m. The strains of B. anthracis that were significantly shorter also sporulated with higher yield at relatively lower temperature. The grouping of B. anthracis strains by size and sporulation temperature did not correlate with their respective virulence. Conclusions:, The spores of Bacillus subtilis and Bacillus atrophaeus (previously named Bacillus globigii), two commonly used simulants of B. anthracis, were considerably smaller in length, diameter and volume than all the B. anthracis spores studied. Although rarely used as simulants, the spores of Bacillus cereus and Bacillus thuringiensis had dimensions similar to those of B. anthracis. Significance and Impact of the Study:, Spores of nonvirulent Bacillus species are often used as simulants in the development and testing of countermeasures for biodefence against B. anthracis. The data presented here should help in the selection of simulants that better resemble the properties of B. anthracis, and thus, more accurately represent the performance of collectors, detectors and other countermeasures against this threat agent. [source] Evaluation of spore extraction and purification methods for selective recovery of viable Bacillus anthracis sporesLETTERS IN APPLIED MICROBIOLOGY, Issue 2 2001D.C. Dragon Aims: To investigate methods of improving anthrax spore detection with PLET. Methods and Results: Comparisons were made of PLET and blood-supplemented PLET to recover and distinguish spores of a variety of Bacillus species. Heat and ethanol purification of spores, and spore extraction from soil with water and high specific gravity sucrose plus non-ionic detergent, were also carried out. Conclusions: PLET was more selective and suitable than blood-supplemented PLET for detection of anthrax spores in the environmental specimens. However, PLET is not an optimal spore recovery medium. Purification of spores with ethanol was as effective as heat purification. High specific gravity sucrose plus detergent extraction solutions may be more sensitive than extraction with water. Significance and Impact of the Study: This study highlights shortcomings with the standard PLET isolation of anthrax spores and describes ways in which the procedure may be improved. [source] Evaluation of body mass index, pre-vaccination serum progesterone levels and anti-anthrax protective antigen immunoglobulin G on injection site adverse events following anthrax vaccination in womenPHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 11 2008Yujia Zhang PhD Abstract Background In 2002, CDC initiated the Anthrax Vaccination Program (AVP) to provide voluntary pre-exposure anthrax vaccination for individuals at high risk for exposure to Bacillus anthracis spores. The AVP offered an opportunity to investigate hypothesized reasons for a reported gender difference in injection site adverse events (AEs) following anthrax vaccine adsorbed (AVA). Objectives To evaluate in women the impact of body mass index (BMI), pre-vaccination serum progesterone levels, and pre-vaccination anti-anthrax protective antigen immunoglobulin G concentrations (anti-PA IgG) on the occurrence of AEs following subcutaneous AVA vaccination. Methods Participants' BMI was determined at enrollment. Also, pre-vaccination blood samples were assayed for serum progesterone and anti-PA IgG. Post-vaccination solicited AEs were recorded by participants using a 4-day diary card. Results Obese group had an elevated risk for arm soreness. Decreased pre-vaccination serum progesterone level was associated with arm swelling. Increased pre-vaccination anti-PA IgG was associated with itching on the arm; and within the obese group, was associated with arm swelling, lump or knot, redness, soreness, and warmth. Conclusions In AVA vaccinated women, obesity was associated with arm soreness and decreased pre-vaccination serum progesterone levels were associated with increased rate of arm swelling. Increased pre-vaccination anti-PA IgG may be associated with an increased frequency of itching on the arm, and in obese women, may increase the occurrence of arm swelling, lump or knot, redness, and warmth. Administering AVA according to a woman's menstrual phase may reduce the occurrence of certain injection site reactions. Copyright © 2008 John Wiley & Sons, Ltd. [source] Photogenerated glycan arrays identify immunogenic sugar moieties of Bacillus anthracis exosporiumPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 2 2007Denong Wang Dr. Abstract Using photogenerated glycan arrays, we characterized a large panel of synthetic carbohydrates for their antigenic reactivities with pathogen-specific antibodies. We discovered that rabbit IgG antibodies elicited by Bacillus anthracis spores specifically recognize a tetrasaccharide chain that decorates the outermost surfaces of the B. anthracis exosporium. Since this sugar moiety is highly specific for the spores of B. anthracis, it appears to be a key biomarker for detection of B. anthracis spores and development of novel vaccines that target anthrax spores. [source] Early events of Bacillus anthracis germination identified by time-course quantitative proteomicsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 19 2006Pratik Jagtap Abstract Germination of Bacillus anthracis spores involves rehydration of the spore interior and rapid degradation of several of the protective layers, including the spore coat. Here, we examine the temporal changes that occur during B. anthracis spore germination using an isobaric tagging system. Over the course of 17,min from the onset of germination, the levels of at least 19 spore proteins significantly decrease. Included are acid-soluble proteins, several known and predicted coat proteins, and proteins of unknown function. Over half of these proteins are small (less than 100 amino acids) and would have been undetectable by conventional gel-based analysis. We also identified 20 proteins, whose levels modestly increased at the later time points when metabolism has likely resumed. Taken together, our data show that isobaric labeling of complex mixtures is particularly effective for temporal studies. Furthermore, we describe a rigorous statistical approach to define relevant changes that takes into account the nature of data obtained from multidimensional protein identification technology coupled with the use of isobaric tags. This study provides an expanded list of the proteins that may be involved in germination of the B. anthracis spore and their relative levels during germination. [source] Murine splenocytes produce inflammatory cytokines in a MyD88-dependent response to Bacillus anthracis sporesCELLULAR MICROBIOLOGY, Issue 2 2007Ian J. Glomski Summary Bacillus anthracis is a sporulating Gram-positive bacterium that causes the disease anthrax. The highly stable spore is the infectious form of the bacterium that first interacts with the prospective host, and thus the interaction between the host and spore is vital to the development of disease. We focused our study on the response of murine splenocytes to the B. anthracis spore by using paraformaldehyde-inactivated spores (FIS), a treatment that prevents germination and production of products associated with vegetative bacilli. We found that murine splenocytes produce IL-12 and IFN-, in response to FIS. The IL-12 was secreted by CD11b cells, which functioned to induce the production of IFN-, by CD49b (DX5) NK cells. The production of these cytokines by splenocytes was not dependent on TLR2, TLR4, TLR9, Nod1, or Nod2; however, it was dependent on the signalling adapter protein MyD88. Unlike splenocytes, Nod1- and Nod2-transfected HEK cells were activated by FIS. Both IL-12 and IFN-, secretion were inhibited by treatment with B. anthracis lethal toxin. These observations suggest that the innate immune system recognizes spores with a MyD88-dependent receptor (or receptors) and responds by secreting inflammatory cytokines, which may ultimately aid in resisting infection. 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