The disclosure provides modified biotin-binding proteins which can be expressed in soluble form in high yield in bacteria. Also provided are fusion proteins comprising the modified biotin-binding protein and an antigen. The disclosure further provides non-hemo lytic variants of alpha-hemolysin from S. aureus and fusion protein comprising non-hemolytic variant of alpha- hemolysin and a biotin-binding domains. Immunogenic compositions comprising the proteins are also disclosed and use of such immunogenic compositions for inducing an immune response or for vaccinating a subject are also disclosed.
