A Preliminary Analysis Of K-mer Based Association Between Lung Microorganisms And Lung Lesions In Pigs

The lung is the main organ of the lower respiratory tract in the body’s respiratory system.When the body breathes,the lungs exchange gas with the outside,and microorganisms complete their colonization in the lungs along with the breathing.Pathogenic microorganisms may enter the lungs,affect normal lung function,and even cause lung diseases.When the sequencing technology and microbial culture technology are not very perfect,the researchers once thought that there is basically no flora in healthy lungs.However,with the emergence and development of microbiological research methods that do not rely on culture,such as high-throughput sequencing technology,people have corrected the erroneous perception that healthy lungs are sterile.In recent years,research on the correlation between lung microbes and diseases has become a research hotspot in the Post-Human Genome Project.Under natural farming conditions,the microbial endostasis of the pig lung remains constant and the invasion of pathogens destabilises the internal microbiome of the lung,subsequently causing lung pathology.Of course,domestic pigs are becoming a new research model for human medicine.The study of pig lung microbes can provide implications for human lung research.In this study,the F6 and F7 heterogeneous populations were used as the main research objects,and the correlation analysis between pulmonary microbial flora and pulmonary lesions based on the k-mer method(the lung lesion score was used as the The degree of disease)was used to explore the species composition of the pig lung flora and the candidate genes that affect the disease of the pig lung,at the same time,the optimal k-mer length value of the gene sequence in this study is evaluated.In this paper,through the k-mer-based correlation analysis of lung lesions and lung microbial metagenomics,we preliminarily explored the influence of pig lung microbial composition and its genes on lung lesions.In this paper,we collected the bronchoalveolar lavage from 44 pigs in the heterogeneous populations with F6(N=10)and F7(N=34)and extracted lavage DNA for metagenomic shotgun sequencing,and recorded the extent of lung lesions in the collected samples and scored them,conducted correlation analysis on lung lesions and lung microbes,and follow-up k-mer traceability,traceability reads assembly,gene prediction,and functional annotation The results were as follows:(1)In the correlation analysis of this study,the significance level of the 90% confidence interval obtained by the correlation analysis of the two groups A and B in this study satisfies the significance level of-log(PA)=6.41587,-log(PB)=7.19218,the significance level The total number of k-mers were 9820 and 436(P<10-7 significantly less than 0.05);(2)The number of non-redundant gene sets predicted by genes was 1106 and 24,respectively,according to the annotations of the Egg NOG database The number of genes received was 135.The filtered genes were enriched in the moderate(MLL)and severe(SVLL)lung disease groups,and there were different enrichments in the severe lung disease A and B groups.Degree performance;(3)Sequence species classification is annotated to the species level according to the two groups of severe lung disease A and B(SVLL-A,SVLL-B)Mycoplasma hyopneumoniae and Ureaplasma urealyticum,the mainly pathogen was Mycoplasma hyopneumoniae;(4)The candidate genes were analyzed for KEGG and GO based on the KEGG database,and a total of 10 KEGG pathways(KEGG Pathway)and 35 GO entries(Gene Ontology Term)were obtained.