Purification and partial characterization of multiple bromoperoxidases from Streptomyces griseus. 
The presence of multiple bromoperoxidases in extracts of Streptomyces griseus Tü 6 was detected.  The enzyme pattern varied with the age of the culture.  A haem-type bromoperoxidase (BPO 2) was always present.  Additionally three nonhaem-type bromoperoxidases (BPO 1a, 1b and 3) were detected and purified to homogeneity.  The Mr of non-denatured BPO 1a was 70,000 +/- 10,000 and those of BPO 1b and 3 were 90,000 +/- 5000.  BPO 1a and 1b were dimers with subunit Mr values of 34,000 and 43,000, respectively.  BPO 3 was a trimer with a subunit Mr of 31,000.  The enzymes differed in their isoelectric points, heat stability, and Km values.  In immunodiffusion experiments BPO 1a and 3 showed partial identity with the nonhaem-type bromoperoxidase from Streptomyces aureofaciens.  The nonhaem-type BPO 1a, 1b and 3 had neither peroxidase nor catalase activity.