Heterologous expression of the Mycobacterium tuberculosis gene encoding antigen 85A in Corynebacterium glutamicum (original) (raw)

1997, Applied and environmental microbiology

By using appropriate Corynebacterium glutamicum-Escherichia coli shuttle plasmids, the gene encoding the fibronectin-binding protein 85A (85A) from Mycobacterium tuberculosis was expressed in C. glutamicum, also an actinomycete and nonsporulating gram-positive rod bacterium, which is widely used in industrial amino acid production. The 85A gene was weakly expressed in C. glutamicum under the control of the ptac promoter from E. coli, but it was produced efficiently under the control of the promoter of the cspB gene encoding PS2, one of the two major secreted proteins from C. glutamicum. The 85A protein was produced in various forms, with or without its own signal sequence and with or without the signal sequence and the NH2-terminal (18-amino-acid) mature sequence of PS2. Western blot analysis with monoclonal antibodies raised against the M. tuberculosis antigen 85 complex showed that recombinant 85A protein was present in the corynebacterial cell wall extract and also released in ex...