title: [Construction and application of prokaryotic expression system of Leptospira interrogans lipL32/1-lipL41/1 fusion gene].
abstract: To construct lipL32/1-lipL41/1 fusion gene and its prokaryotic expression system and to determine frequencies of carrying and expression of lipL32 and lipL41 genes in L.interrogans wild strains and specific antibody levels in sera from leptospirosis patients.
  
  
  
  lipL32/1-lipL41/1 fusion gene was constructed using linking primer PCR method and the prokaryotic expression system of the fusion gene done with routine techniques. SDS-PAGE was used to examine expression of the target recombinant protein rLipL32/1-rLipL41/1. Immunogenicity of rLipL32/1-rLipL41/1 was identified by Western blot. PCR and MAT were performed to detect carrying and expression of lipL32 and lipL41 genes in 97 wild L.interrogans strains. Antibodies against products of lipL32 and lipL41 genes in serum samples from 228 leptospirosis patients were detected by ELISA method.
  
  
  
  The homogeneity of nucleotide and putative amino acid sequence of lipL32/1-lipL41/1 fusion gene were 99.9 % and 99.8 % in comparison with the reported sequences. Expression output of the target recombinant protein rLipL32/1-rLipL41/1, mainly present in inclusion body, accounted for 10 % of the total bacterial proteins. Both the rabbit antisera against rLipL32/1 and rLipL41/1 could combine to rLipL32/1-rLipL41/1. 97.9 % and 87.6 % of the L.interrogans wild strains had lipL32 and lipL41 genes, respectively. 95.9 % and 84.5 % of the wild strains were positive for MAT with titers of 1:4 - 1:128 using rabbit anti-rLipL32s or anti-rLipL41s sera, respectively. 94.7 % - 97.4 % of the patients'serum samples were positive for rLipL32s antibodies, while 78.5 % - 84.6 % of them were rLipL41s antibodies detectable.
  
  
  
  lipL32/1-jlipL41/1 fusion gene and its prokaryotic expression system were successfully constructed. The expressed fusion protein had qualified immunogenicity. Both the lipL32 and lipL41 genes are extensively carried and frequently expressed by different serogroups of L.interrogans, and their expression products exhibit cross-antigenicity.
authors.affiliation: Department of Medical Microbiology and Parasitology, College of Medicine, Zhejiang University, Hangzhou 310031, China.
authors.forename: Dong-jiao
authors.initials: DJ
authors.lastname: Luo
authors.forename: Jie
authors.initials: J
authors.lastname: Yan
authors.forename: Ya-fei
authors.initials: YF
authors.lastname: Mao
authors.forename: Shu-ping
authors.initials: SP
authors.lastname: Li
authors.forename: Yi-hui
authors.initials: YH
authors.lastname: Luo
authors.forename: Li-wei
authors.initials: LW
authors.lastname: Li
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D004797:Enzyme-Linked Immunosorbent Assay; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics*; D006801:Humans; D007921:Leptospira interrogans / Q000235:genetics*; D007922:Leptospirosis / Q000276:immunology / Q000382:microbiology; D008074:Lipoproteins / Q000235:genetics*; D011387:Prokaryotic Cells / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; C406589:LipL32 protein, Leptospira; D008074:Lipoproteins; D011993:Recombinant Fusion Proteins; C081904:ompL1 protein, Leptospira