Studies on peroxidase production and detection of -like catalase-peroxidase gene in a species isolated from Hogsback forest reserve, South Africa.

This study sought to determine the process conditions for optimum peroxidase production by a species ( sp. FALADE-1-KX640922) isolated from Hogsback forest reserve in South Africa and characterize the peroxidase gene in the bacteria. We optimized peroxidase production by manipulating the environmental and nutritional parameters under submerged fermentation. Subsequently, the gene encoding heme-peroxidase was determined through nested polymerase chain reaction and Sanger DNA sequencing. The studied bacteria had maximum peroxidase production at pH 8, 30 °C and 150 rpm. The addition of guaiacol to lignin fermentation medium enhanced peroxidase production by over 100 % in the studied bacteria. However, the other lignin monomers (veratryl alcohol, vanillin, vanillic acid and ferulic acid) repressed the enzyme activity. Modification of the fermentation medium with ammonium sulphate gave the maximum peroxidase yield (8.87 U mL). Under the predetermined culture conditions, sp. FALADE-1 expressed maximum specific peroxidase activity at 48 h (8.32 U mg). Interestingly, a search of the sequenced gene in PeroxiBase showed 100% similarity to catalase-peroxidase gene (), as well, the deduced protein sequence clustered with bacterial catalase-peroxidases and had a molecular weight of about 11.45 kDa with 7.01 as the estimated isoelectric point. Subsequently, the nucleotide sequence was deposited in the National Center for Biotechnology Information (NCBI) repository with the accession number MF407314. In conclusion, sp. FALADE-1 is a promising candidate for improved peroxidase production.