Sequence and expression of the Mycobacterium leprae dnaJ gene

Study of Mycobacterium leprae, the causative agent of leprosy, has been advanced by the isolation of genes encoding mycobacterial proteins including dnaK encoding the M. leprae 70 kDa heat shock protein. The sequence downstream from dnaK revealed a second open reading frame coding for a protein of 389 amino acids with a calculated molecular mass of 41.2 kDa. Sequence analysis demonstrated significant DNA homology with the dnaJ gene of other organisms. High amino acid sequence identity was obtained between the DnaJ protein of M. leprae and M. tuberculosis (89%) with significant divergence between the two occurring only at the C-terminal end. The expressed recombinant DnaJ protein had a molecular mass of 42 kDa.