Showing papers on "Bacillus anthracis published in 1987"
TL;DR: The potential for flies to mechanically transmit anthrax suggests that fly control should be considered as part of a program for control of epizootic anthrax and supports recent anecdotal reports of fly-bite-associated cutaneous human anthrax.
Abstract: We evaluated the potential of stable flies, Stomoxys calcitrans, and two species of mosquitoes, Aedes aegypti and Aedes taeniorhynchus, to transmit Bacillus anthracis Vollum 1B mechanically. After probing on Hartley guinea pigs with a bacteremia of ca. 10(8.6) CFU of B. anthracis per ml of blood, individual or pools of two to four stable flies or mosquitoes were allowed to continue feeding on either uninfected guinea pigs or A/J mice. All three insect species transmitted lethal anthrax infections to both guinea pigs and mice. Both stable flies and mosquitoes transmitted anthrax, even when they were held at room temperature for 4 h after exposure to the bacteremic guinea pig before being allowed to continue feeding on the susceptible animals. This study confirms that blood-feeding insects can mechanically transmit anthrax and supports recent anecdotal reports of fly-bite-associated cutaneous human anthrax. The potential for flies to mechanically transmit anthrax suggests that fly control should be considered as part of a program for control of epizootic anthrax.
133 citations
TL;DR: The transfer of plasmids by mating from four Bacillus thuringiensis subspecies to Bacillus anthracis and Bacillus cereus recipients was monitored by selecting transcipients which acquired plasmid pBC16 (Tcr), and DNA-DNA hybridization experiments suggested that DNA homology exists among pXO13, pX o14, and pXo16.
Abstract: The transfer of plasmids by mating from four Bacillus thuringiensis subspecies to Bacillus anthracis and Bacillus cereus recipients was monitored by selecting transcipients which acquired plasmid pBC16 (Tcr). Transcipients also inherited a specific large plasmid from each B. thuringiensis donor at a high frequency along with a random array of smaller plasmids. The large plasmids (ca. 50 to 120 megadaltons), pXO13, pXO14, pXO15, and pXO16, originating from B. thuringiensis subsp. morrisoni, B. thuringiensis subsp. toumanoffi, B. thuringiensis subsp. alesti, and B. thuringiensis subsp. israelensis, respectively, were demonstrated to be responsible for plasmid mobilization. Transcipients containing any of the above plasmids had donor capability, while B. thuringiensis strains cured of each of them were not fertile, indicating that the plasmids confer conjugation functions. Confirmation that pXO13, pXO14, and pXO16 were self-transmissible was obtained by the isolation of fertile B. anthracis and B. cereus transcipients that contained only pBC16 and one of these plasmids. pXO14 was efficient in mobilizing the toxin and capsule plasmids, pXO1 and pXO2, respectively, from B. anthracis transcipients to plasmid-cured B. anthracis or B. cereus recipients. DNA-DNA hybridization experiments suggested that DNA homology exists among pXO13, pXO14, and the B. thuringiensis subsp. thuringiensis conjugative plasmids pXO11 and pXO12. Matings performed between strains which each contained the same conjugative plasmid demonstrated reduced efficiency of pBC16 transfer. However, in many instances when donor and recipient strains contained different conjugative plasmids, the efficiency of pBC16 transfer appeared to be enhanced.
99 citations
TL;DR: No correlation was found between rate of spore germination and virulence or between susceptibility of animal species to anthrax andSpores germinated poorly at high cell densities unless the alanine racemase inhibitor O-carbamyl-D-serine was added to the germination medium.
Abstract: Spores of Bacillus anthracis germinated poorly at high cell densities unless the alanine racemase inhibitor O-carbamyl-D-serine was added to the germination medium. Spores derived from a variety of strains of B. anthracis germinated optimally at 22 degrees C. No correlation was found between rate of spore germination and virulence or between susceptibility of animal species to anthrax and spore germination rate using sera from those animals as the germination medium.
66 citations
TL;DR: Restriction endonuclease analysis of these plasmids shows that they are not related and their GC contents are close to the GC content of B. anthracis genomic DNA.
36 citations
Journal Article•
TL;DR: The experience suggests that the Sterne strain of anthrax vaccine can induce fatal disease when given to young llamas and should be used only with extreme care and in face of strong "at risk" situations.
Abstract: Two llama calves died 3 days after inoculation with anthrax vaccine. Concurrent administration of ivermectin and other biologics may have enhanced the infectivity of the Sterne strain vaccine of Bacillus anthracis. This experience suggests that the Sterne strain of anthrax vaccine can induce fatal disease when given to young llamas and should be used only with extreme care and in face of strong "at risk" situations.
21 citations
TL;DR: A kanamycin-resistance plasmid, pUB110, was introduced into Bacillus anthracis by a newly devised method of transformation.
Abstract: A kanamycin-resistance plasmid, pUB110, was introduced into Bacillus anthracis by a newly devised method of transformation. The transformation frequency was ca. 1 × 103 cells/1 μg DNA.
9 citations
16 Jul 1987
TL;DR: The inbred mouse model for anthrax is recommended for testing the efficacy and safety of new vaccines and characterizing the mechanisms of immunity to anthrax.
Abstract: : The safety and protective efficacy of the Sterne vaccine strain of Bacillus anthracis and of a recombinant Bacillus subtilis strain were investigated in mice. Strains of mice which vary in their natural resistance to killing by the Sterne strain were used. Vaccination with Sterne spores protected Sterne-resistant CBA/J mice against challenge with a fully virulent strain of B. anthracis, but only at vaccine doses within a magnitude of the 50% lethal dose (LD50). The Sterne-susceptible A/J mice were not protected. Bacillus subtilis recombinant strain PA2, which produces the protective antigen component of anthrax toxin, protected CBA/J but not A/J mice. Both strains of mice developed high antibody titers to protective antigen. BALB/cJ and CBA/J mice were similarly resistant to lethal Sterne infection, - but BALB/cJ mice were more difficult to protect by immunization with either live vaccine. The inbred mouse model for anthrax is recommended for testing the efficacy and safety of new vaccines and characterizing the mechanisms of immunity to anthrax.
1 citations