fibrinogen and fibronectin binding activity and immunogenic nature of choline binding protein m

Background: choline-binding proteins (cbps) are a group of surface-exposed proteins, which play crucial and physi-ological roles in streptococcus pneumoniae. the novel member of cbps, choline-binding protein m (cbpm) may have binding activity to plasma proteins. this study aimed to clone and express cbpm and demonstrate its interaction with plasma proteins and patients’ sera. methods: the total length of cbpm gene was cloned in pet21a vector and expressed in bl21 expression host. verifi-cation of recombinant protein was evaluated by western blot using anti-his tag monoclonal antibody. binding ability of the recombinant protein to plasma proteins and the interaction with patients’ sera were assessed by western blot and elisa methods. results: the cbpm gene was successfully cloned into pet21a and expressed in bl21 host. binding activity to fibro-nectin and fibrinogen and antibody reaction of cbpm to patients’ sera was demonstrated by western blot and elisa methods, respectively. conclusion: cbpm is one of the pneumococcal surface-exposed proteins, which mediates pneumococcal binding to fibronectin and fibrinogen proteins.