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Cyhalothrin was isolated as the sole carbon source, the growth of bacteria, named GF-3 from the the pesticide plant wastewater discharge near the mouth of the activated sludge. According to their physiological and biochemical characteristics and the 16SrDNA gene sequence (GenBank sequence number EU219735) similarity analysis, this strain was identified as the genus Bacillus (Bacillus sp.) O GF-3 strains grow well at about pH8-9; optimum growth temperature 30 ° C; aerobic growth; having a salt tolerance, but is preferably growth range in 0-0.2g/100mL salt; GF-3 grow better when galactose, glucose and fructose as carbon source; organic nitrogen as nitrogen source growth significantly better than inorganic nitrogen. GF-3 to ceftazidime and amoxicillin strong resistant to card to penicillin, rifampin, streptomycin, kanamycin, gentamicin, tetracycline, chloramphenicol, erythromycin, itching fluorine gatifloxacin no resistance. Degradation characteristics on the GF-3 The results showed that the strain degradation cyhalothrin optimum temperature is about 30 ° C, the optimum pH 7-10; the cyhalothrin degradation rate and the amount of initial inoculum relationship, inoculum in the range of 3-15% have access to a higher degradation rate; GF-3 could effectively degrade the concentration of 50-600mg / L cyhalothrin, within 24 hours of 100mg / L cyhalothrin degradation rate of 98.4% . GF-3 in addition to degradation cyhalothrin, but also the degradation of fenpropathrin, cypermethrin, deltamethrin, beta-cypermethrin; GF-3 in the presence of the size of 6500bp and 3500 bp plasmid, plasmid curing GF-3 degradation cyhalothrin is not affected, indicating that the the cyhalothrin degradation has nothing to do with the plasmid. GF-3 crude enzyme solution in the reaction temperature to 40 ° C, pH value of 9.0, the degradation activity maximum; enzyme stability in the 30-60 ° C, 60 ° C for 4h still 50% of the enzyme activity; different organic solvents on activity of the enzyme was inhibited by which its strongest inhibition ethanol; different metal ions in different concentrations enzyme activity would have a certain impact, Ag, Cu2 and Mg2 at a concentration of 0.2 mmol, 2 mmol and 20 mmol on enzyme activity were significantly inhibited, Ca2 and Ni at a concentration of 20mmol on enzyme activity inhibition; 0.2 mmol, 2 mmol and 20 mmol of Mn2 and Zn2, 0.2 mmol of Ni, Fe3 0.2 mmol and 0.2 mmol, 2 mmol Ca2 on enzyme activity have little effect; 0.2 mmol 2 mmol and 20mmol CO2,, 2 mmol and 20mmol the Fe3 and 2 mmol of Ni on enzyme activity certain role in promoting. Enzyme localized test degrading enzymes for extracellular enzymes; the substrate induction tests showed that degrading enzymes constituted enzymes. Bacillus sp. GF-3, cyhalothrin space pollution bioremediation of soil and its influencing factors in the laboratory under simulated conditions. The results showed that the inoculum size of 108 and 109 · kg-the degradation effect is more obvious, add organic fertilizer and glucose can promote the degradation of the Bacillus sp. GF-3 cyhalothrin.
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