A gene encoding the major secreted fibrinolytic protein of Bacillus amyloliquefaciens CH86-1 was cloned from genomic DNAs. DNA sequencing showed that the gene, aprE86-1, could direct the synthesis of a mature protein 275 amino acids in length after processing. When aprE86-1 was introduced into B. subtilis, a mature 27-kDa protein was produced as expected. The fibrinolytic activity of the B. subtilis transformant (TF) was higher than that of B. amyloliquefaciens CH86-1, showing the possibility of increasing the fibrinolytic activity of Bacillus strains through genetic engineering.