Screening And Identification Of Swainsonine Degrading Bacteria

Locoweed, the most serious poisonous plants which was harm to the sustainable development ofanimal husbandry in the world, is the common name of the genera Astragalus sp. and Oxytropis sp. Itscharacteristic is barren, drought resistant, earlier, strong reproduction. Animal feed locoweed performancehas addicted to addiction, accumulation of poisoning。Locoweeds contain swainsonine, which is the principal agent responsible for locoism in animals. SWis an inhibitor of mannosidase in cell, which can alter metabolism of glycoprotein, leads to cellularvacuolation and cellular death, finaly can results in animal death. Infuence on the properties of animalbreeding, easy to abortion, malformation, weak fetal and other symptoms caused by animal reproductiveperformance barriers. Brings the serious economic losses to livestock industry. Research shows thatlocoweed contains rich nutrition and mineral elements, its nutritional value and alfalfa rather, its reasonabledevelopment use not only can solve the problem of shortage of forage, but also can reduce locoweedpoisoning caused economic losses. The dynamics change of nutritional evaluation and swainsoninnecontent of Oxytropis glabra DC during growth in South Xinjiang, And screened from the soil able todegrade SW bacteria, the SW-degrading baeteria was identified by16S rDNA identification. Thisexperiment locoweed was lay the foundation for the development and utilization.1.The dynamics change of nutritional evaluation and SW content of O. glabra DC during growthwere measuredThe dynamics change of nutritional evaluation and SW content of South Xinjiang during growth weremeasured, find that with the growth of O. glabra DC, its nutrition composition has a rising trend. The peakperiod of content of crude protein, ether extract, crude ash and calcium arrived in flowering stage, the peakperiod of content of dry matter and phosphonium arrived in pod-setting stage, the peak period of content ofNDF and ADF arrived in defoliation stage. Determination of SW were significantly different during test,the peak period was pod-setting stage, then content of SW in O. glabra DC reduced after pod-setting stage.2. Soil treatmentCollected from Xinjiang Akqi County habitat0～30cm soil, weighed gravel removal10g soil added90mL sterile water, mix well static, and the supernatant add beef extract-peptone37℃overnight. Fromtotal alkaloid extracted by adding inorganic liquid culture medium, transfer once every four days, transferthree times, the liquid medium uniformly applied to inorganic solid medium containing alkaloids, picked adifferent colony morphology and gram staining different cell morphology observed pure culture of bacteria.3.Screening of SW-degrading bacteria in soil and determing the degradation abilityStrains have been isolated and purified after taking in LB liquid medium37℃,200r/min overnightculture, bacteria pipetted in SW inorganic salt medium was added so that the inorganic salt in the inorganicsalt medium, the medium content from30mg/L adapter once every four days, gradually increasing SWcontent to100mg/L medium containing inorganic salts, found that there are two strains of bacteria capableof degrading, XJAHQ5, XJAHQ26strains the degradation efficiency of20.86%and30.12%.4. Idetification of the SW-degrading bacteriaStrain XJAHQ5and XJAHQ26have the ability to degrade, of the16S were conserved sequences inthe NCBI BLAST comparison, download the similar strains use MEGE6.0software to establish unrootedphylogenetic tree, to understand the evolutionary relationship strains identified two strains found it isPseudomonas putida. Cultured at different pH conditions, the strain found in XJAHQ26can be grown inpH4to10, which adapt to a wide range of development has a certain value.