title: Homology modeling three-dimensional structure of AnxB1 and reducing its immunogenicity by sequence-deleted mutagenesis.
abstract: AnxB1, a novel annexin previously isolated from Cysticercus cellulose, shows high thrombi affinity and anticoagulant activity in vivo. In order to investigate the relationship between structure and biological function, a predicted three-dimensional (3D) model of AnxB1 was generated by homology modeling. This model contains four homologous internal-domains and the Ca trace of domain I, II and IV shows high similarity. Based on the structure characterization, four sequence-deleted mutants were constructed and expressed as GST fusion proteins in E. coli. Two of the mutants, GST-M3 and GST-M4 reserved high anticoagulant activity (p<0.01 vs. GST). Furthermore, compared with the wild type GST-AnxB1, the immunogenicity of GST-M3 and GST-M4 was reduced significantly (p<0.01) and the molecular weight was lowered to 27 kD and 34 kD, respectively. These observations laid a solid foundation for further study on developing new thrombolytic agents with higher efficiency and lower side effect.
authors.affiliation: Department of Medical Genetics, Second Military Medical University, Shanghai 200433, China.
authors.forename: Hongli
authors.initials: H
authors.lastname: Yan
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Song
authors.forename: Fan
authors.initials: F
authors.lastname: Liu
authors.forename: Yan
authors.initials: Y
authors.lastname: He
authors.forename: Shuhan
authors.initials: S
authors.lastname: Sun
mesh_terms: D017302:Annexins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D008958:Models, Molecular; D016296:Mutagenesis / Q000235:genetics*; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion / Q000235:genetics*; D013696:Temperature
chemical_list: D017302:Annexins; D011993:Recombinant Fusion Proteins