title: Characterization of a monoclonal antibody to Spiroplasma eriocheiris and identification of a motif expressed by the pathogen.
abstract: Tremor disease (TD) has been found to be a lethal epidemic in Chinese mitten crab during recent years. A new species of spiroplasma, Spiroplasma eriocheiris (S. eriocheiris), was identified as the pathogen causing TD. In order to acquire appropriate biological tools for characterizing this newly discovered pathogen, we developed a new S. eriocheiris specific monoclonal antibody (mAb) 6H7. The antibody showed high binding affinity to S. eriocheiris (K(a)=6.25×10(8) M(-1)) and it bound to the adhesin-like protein (ALP41) of S. eriocheiris in Western blot analysis. Screening of a commercially available 12-mer linear peptide library by using 6H7 as bait led to isolation of a consensus sequence (FQGINHYNQMER). The clone displaying this sequence exhibited a significant, dose-dependent binding to 6H7 and inhibited the binding of S. eriocheiris to 6H7, suggesting a similar epitope between the sequence and S. eriocheiris. Homology searches and multiple sequence alignments indicated moderate homology between the consensus peptides and the ALP of S. eriocheiris. Thus, an internal image of 6H7 binding epitope might be buried in ALP41 of S. eriocheiris. In conclusion, 6H7 is a promising mAb to identify S. eriocheiris and the consensus sequence can be used in future research on the characterization of S. eriocheiris and its pathogenesis.
authors.affiliation: The Laboratory of Developmental Genes and Human Diseases, Ministry of Education, Southeast University Medical School, Nanjing 210009, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Haixun
authors.initials: H
authors.lastname: Bao
authors.forename: Fengqin
authors.initials: F
authors.lastname: Miao
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Shen
authors.forename: Youjie
authors.initials: Y
authors.lastname: He
authors.forename: Wei
authors.initials: W
authors.lastname: Gu
authors.forename: Qingguo
authors.initials: Q
authors.lastname: Meng
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
authors.forename: Jianqiong
authors.initials: J
authors.lastname: Zhang
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D001483:Base Sequence; D015153:Blotting, Western; D003386:Brachyura / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000032:analysis / Q000235:genetics / Q000276:immunology; D006825:Hybridomas; D008969:Molecular Sequence Data; D019151:Peptide Library; D017434:Protein Structure, Tertiary; D013149:Spiroplasma / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification
chemical_list: D018829:Adhesins, Bacterial; D000911:Antibodies, Monoclonal; D000939:Epitopes; D019151:Peptide Library