Epidemiolody Survey And Preliminary Study On The Infection Mechanism Of Cow Brucellosis In Tongliao District Of Inner Mongolia

Brucellosis （Brucellosis, referred to as brucellosis caused by Brucella）is themain source of infection in cattle for zoonotic diseases. At present, there are manycountries in human and animals brucellosis, after2000, human and animalsbrucellosis in China has the tendency to rise year by year, also have outbreaks ofsingle group and livestock and animal husbandry, health of people caused great harm.All these reflect the prevalence of brucellosis in domestic animals. Reasons forbrucellosis treatment and control involves many, its pathogenic mechanism,intracellular survival mechanism is not very clear is the key.In this study, in2009~2011years of epidemiological survey of brucellosis in aplurality of different cows in Inner Mongolia Tongliao region, we collected5875unimmunized cow serum and1931milk samples. Using RBT, SAT, MRT, CFT andother four kinds of different serological detecting method, results show that, TongliaoCity dairy cattle brucellosis was prevalent in the infection rate, showing noequilibrium obvious field, and more serious. Preliminary view may be associated withthe disease prevention and control, feeding cycle is long, elimination rate low, cowtrade, transport frequently and so on.In order to control the epidemic of brucellosis better, we study on the molecularmechanism of brucellosis, looking for the pathogenic mechanism of brucellosis.Brucella infection due to full-time macrophages and non-professional phagocytes, andin which the survival and reproduction, considering the interaction between thebacterial protein and host cell proteins may have correlation with Brucella infection.The study found, because Omp22belongs to a member of the third group of Brucellaouter membrane protein of Omp22/Omp31family, if the individual cow Omp22genedeletion, the body of Brucella mutant did not induce host abortion, and proliferation invivo, and toxicity than the parent strain decreased significantly, and the humoral immunity is weakened, in a certain extent, thus, not only is the Omp22virulencefactors but also the immunogenic protein. Based on the experimental results, in orderto further explore the mechanism of the molecular pathogenesis of Brucella parasitismand intracellular, this research will use diagnosed by544A strain infected cDNA micemacrophage library, then Omp22protein as bait, and then from the library screeningand identification of interacting proteins.Use of molecular biology techniques of Brucella544A strain Omp22was cloned,sequenced, bioinformatics analysis. Firstly, to construct the bait vector （where theOmp22is connected to the pSos carrier）, and detect the bait vector of self-excitedactivity, toxicity and membrane localization. In the experiment, screening interactionproteins for bait plasmid and pMyr-cDNA library plasmids were transformed intocdc25H α yeast competent cells of this process. The results showed that, Omp22genewas cloned correctly diagnosed by16M strain, the bait vector for yeast cells withoutactivation, membrane localization is accurate, non-toxic side effects, can be used inthe yeast two-hybrid system.In the experiment, the bait plasmid and pMyr-cDNA library plasmids weretransformed into cdc25H α yeast yeast two-hybrid competent cells, the resultsobtained2positive clones, sequenced two genes are NDAH reductase equipment（Mus musculus NADH dehydrogenase factor2ubiquinone）. Through the aboveexperiment, we can put forward the following hypothesis: Omp22and Ndufaf2combined, can promote the increase of NADH concentration in the cells, increase theactivity of NADH, reduce the oxidation of macrophages on Brucella killer, so as tocreate a conducive to the survival of Brucella intracellular conditions.To sum up, the study of brucellosis in livestock husbandry in Inner MongoliaTongliao area production line appears, epidemiological investigation, master woodGacha （Village）the brucellosis epidemic situation, and relying on laboratory testing,provide technical support for the judgement of the epidemic. In addition, this researchtake the Tongliao area the Brucella strains screening of Brucella outer membraneprotein Omp22and third groups of identified proteins interacting with Ndufaf2, whichlays a foundation for further study of Brucella Omp22immunogenicity and relatedfunctions, and provide a theoretical basis for revealing the molecular mechanism of pathogenesis and parasitic Brucella intracellular.