| As a biologic weapon, Bacillus anthracis spores is a standard biologic agent. After the terrorist attack on September 11, all over the world have pay more attention about the threat of biologic weapon by Bacillus anthracis spores again. Researching and establishing new techniques of treatment and prevention for anthrax have became an important mission for military medicine and public health. Bacillus anthracis spores maintains the dormant state and protects the cellular compartment from environmental factors, such as heat, dryness, radiation, chemical disinfectant and hydrostatic pressure insult. Spores of Bacillus anthracis remain viable for years even decades in soil. It is difficult to destroy the spores in expanse contaminated area when attacked by powder or aerosol of Bacillus anthracis spores. At all time, the issue of persist threat to people by Bacillus anthracis is a big problem in biologic weapon defending. At present, the general ways of decontamination are as follows:(1) close the focus area for a long time and take the effect of decontamination by self-purification;(2) carry out measure of downright disinfection immediately by using chemical disinfectants with a high dosage. The both ways have obvious disadvantage, such as limited effect of disinfection, long treatment time, great economic loss and lead to environment contamination again. Destroyed the balance of relationship between organism and their environment. So study about the new efficacious method of killing Bacillus anthracis spores in field environment has great significance in biologic weapons defending. In order to develop the technique of phage lysing of host bacterium for biologic weapons safeguard, the Bacillus anthracoides were used as test bacterium. we screened the Bacillus anthracoides bacteriophages from natural soil environment. Then the phage's characteristic, such as morphologic features, growth curve, antigenic and nucleic acid peculiarity were observed. For studies the killing effect, we have selected some nutrient germinants and validate their co-operation effect with bacteriophages to destroy Bacillus anthracoides. The results are as follows. 1.Using Bacillus anthracoides(80-08), a bacteriophage strain, phage03Z-1 was isolated from soil samples. Test data showed that this bacteriophage was lytic bacteriophage, the titers of original liquid of phage is higher than 1010 pfu/ml. It could lyse Bacillus anthracoides (80-08) and Bacillus pumilus (ATCC 27142). After 30-cycled culture, the bacteriophage preserved the characteristic of multi-host-lysis and replication activity. 2.Under the electron microscope, the bacteriophage 03Z-1 is a rotundity or ellipse particle with a diameter of 22～45nm, tailless. The plaque with a diameter of 4～5mm is transparent without turbid loop. The anti-serum K value of the phage is 284.54. One-step-growth test showed that bacteriophage 03Z-1 has a higher adsorption rate, a shorter incubation period and a higher lytic efficacy. Analysis test for Nucleic acid revealed that bacteriophage 03Z-1 is a double-stranded RNA bacteriophage with about 20000bp.3. At the most suitable condition (37°C, pH 7.9), the nutrient germinant with 6mmol/L inosine could induce germination at the rate of 57.6%. At the treatment condition (30°C, pH 8.9), the nutrient germinant with 70mmol/L L-alanine could induce germination at the rate of 74.5%. Mixing the two nutrients germinant, the blending germinant could increase the germination effect. The rate increased to 85.6%. Under the transmission electron microscope, the germinated spores' coat and cortex were breakdown and degraded. And the core was exposure completely. In the germination reaction of spores, the different cations such as sodium ions, calcium ions in nutrient germinant have different effect. Sodium ions and ammonium ions induced and facilitated the germination in germinant of inosine and L-alanine respectively.4. Treating the spores in contaminated soil by bacteriophage 03Z-1, the germicidal test showed that the disinfected rate of B...
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