Purification, characterization and comparison of two non-haem bromoperoxidases from Streptomyces aureofaciens ATCC 10762

Abstract

Two non-haem bromoperoxidases (BPO 1 and BPO 2) were purified from the 7-chlorotetracycline-producing strain Streptomyces uureofaciens ATCC 10762. Both enzymes showed azide-insensitive brominating activity, and bromide-dependent peroxidase activity. BPO 1 was a dimer (Mc 65000) with subunits of identical size (M, 31 OOO). The PI was estimated to be 4.5. The enzyme did not cross-react with antibodies raised against the non-haem bromoperoxidase ( M , 90000) from S. aureofmiens TU24, a strain that also produces 7-chlorotetracycline. The M, of BPO 2 was estimated to be 90000. The enzyme had three identical subunits (M, 31 000), and its isoelectric point was 3.5, identical with that of the bromoperoxidase from S. aweofmiens TU24. Moreover, BPO 2 was immunologically identical with the bromoperoxidase from S. aweofmiens Tii24, although both it and BPO 1 could be distinguished electrophoretically from the latter bromoperoxidase.

Chloroperoxidase from Streptomyces lividans: isolation and characterization of the enzyme and the corresponding gene

“…However, during the cloning of the cpoT gene from S. aureofaciens Tu24, brominating activity had been detected in this strain. Like other previously isolated haloperoxidases, CPO-L was not detected in crude extracts (36,39,41) but only after dialysis or ion-exchange chromatography. This phenomenon may be due to one or several inhibitory substances of unknown structure.…”

“…The absorption spectrum of the native enzyme did not exhibit any absorption bands in the visible region of the spectrum (Fig. 2) pared by Ouchterlony gel diffusion assay with BPO-A1 and BPO-A2 from S. aureofaciens ATCC 10762 (39), CPO-T from S. aureofaciens Tu24 (36), and CPO-P from P. pyrrocinia ATCC 15958 (42) with antisera raised against homogeneous CPO-T and CPO-P. The chloroperoxidase produced by S. lividans TK64 showed partial cross-reaction with CPO-P ( Chlorination of indole.…”

“…In the last few years, a number of prokaryotic nonheme haloperoxidases have been purified from different bacteria and characterized (36,39,42). In these enzymes, which represent the third group of haloperoxidases, no prosthetic groups or metal ions are detectable.…”

Biological Effects and Biosynthesis of Brominated Metabolites

“…Br [227] aureofaciens Acinetobacter Br [102] calcoaceti species (references in [57,240]). Examples of reactions mediated by mammalian lactoperoxidase are given later in this section, and of the eosinophil peroxidase in the sections "Simple Phenols" and "Iminazoles, Quinolines, Pyrimidines, Pyrrolopyrimidines, and Purines".…”

Improvement of the stability and activity of the BPO-A1 haloperoxidase from Streptomyces aureofaciens by directed evolution

“…Among metal-free haloperoxidases, BPO-A1 from Streptomyces aureofaciens has been relatively well studied (Pelletier et al, 1994;Hofmann et al, 1998). However, because it has a homodimeric structure (Weng et al, 1991), enzyme deactivation could be caused by subunit dissociation (FernandezLafuente, 2009). Thus, the development of a stable metal-free haloperoxidase is desired for industrial application.…”