In vitro evolutional selection of a combinatorial phage library displaying randomly-rearranged various binding domains of SpA and SpG with four human IgG subclasses.
- Author:
Peipei QI
1
;
Yingying DING
;
Lili WU
;
Qiuli CHEN
;
Jinhong WANG
;
Chao LIU
;
Wenting LIAO
;
Jing ZHANG
;
Jie CAO
;
Wei PAN
Author Information
1. Department of Microbiology, Second Military Medical University, Shanghai 200433, China.
- Publication Type:Journal Article
- MeSH:
Amino Acid Sequence;
Antibody Specificity;
Bacterial Proteins;
immunology;
metabolism;
Binding Sites;
Binding, Competitive;
Evolution, Molecular;
Immunoglobulin G;
immunology;
metabolism;
Molecular Sequence Data;
Peptide Library;
Sequence Alignment;
Staphylococcal Protein A;
immunology;
metabolism
- From:
Chinese Journal of Biotechnology
2012;28(9):1093-1105
- CountryChina
- Language:Chinese
-
Abstract:
Protein A and protein G are two well-defined immunoglobulin (Ig)-binding proteins (IBPs), which show affinity for specific sites on Ig of mammalian hosts. Protein A and protein G contained several highly homologous IgG-binding domains which had been demonstrated to have function to bind to IgG. Whether combinations of Ig-binding domains of various IBPs could produce useful novel binding properties remains interesting. We constructed a combinatorial phage library which displayed randomly-rearranged A, B, C, D and E domains of protein A, B2 and B3 domains of protein G. Four rounds molecular evolution of this library directed by all four human IgG subclasses respectively generated a common arrangement of D-C respectively which didn't exist in SpA. The dynamic loss of control phages and increase of the phages displaying two or more binding domains, especially the selective enrichment of D-C and strict selection of its linking peptides demonstrated the efficient molecular evolutions and the significance of the selected D-C arrangement. The phage binding assays confirmed that D-C possessed a binding advantage with four human IgG subclasses compared to SpA. In this work, a novel combination of Ig-binding domains, D-C, was obtained and presented the novel Ig binding properties which provided a novel candidate molecule for the purification, production and detection of IgG antibodies and a new approach for the further study of structures and functions of IBPs.
