## 3 Results and Discussion
### PCR Detection of Peroxidase Gene  
Molecular optimization and genetic engineering seem to be the best option for increased enzyme production. Hence, the imperativeness of detecting the gene responsible for the expression of the enzyme of interest in an organism. Figure 4a shows the gel picture of the PCR amplified product from _Ensifer ahaerens_ NWODO-2. The results showed the band size of the amplified gene as 800 bp. The search of the nucleotide sequence in the UniProt Knowledgebase using blastx program showed 70.5% similarity to _Ensifer ahaerens_ uncharacterized protein (ANK75658). However, phylogenetic analysis of the expressed protein sequence and selected bacterial heme peroxididases in the PeroxiBase database (peroxibase.toulouse.inra.fr) showed that it clustered with catalase-peroxidases (Figure 4b). This finding suggests that the amplified gene from _Ensifer ahaerens_ NWODO-2 may encode a novel catalase-peroxidase with an estimated molecular weight of approximately 31 kDa and isoelectric point of about 11. Bacterial catalase-peroxidases (KatG) belong to class I peroxididases of the peroxidase-catalase superfamily of heme-peroxidases [66]. Other members of class I peroxididases include yeast cytochrome c peroxididases and ascorbate peroxididases. The KatG gene encodes the expression of both catalase and peroxidase activity [67] in an organism. This therefore suggests that peroxidase activity expressed in _Ensifer ahaerens_ NWODO-2 may be attributed to the presence of the KatG gene in the new bacteria strain. Hence, the gene could be explored for large scale production of catalase and peroxidase through genetic engineering, which has proven difficult in fungi [15]. Apart from the fact that the KatG gene encodes peroxidase activity, bacteria catalase-peroxidases have recently been implicated in the degradation of lignocellulosic [68; 69]. Therefore, the presence of the KatG gene in _Ensifer ahaerens_ NWODO-2 further attests to its ligninolytic potential, which was previously reported by the authors [14]. \begin{table}
\begin{tabular}{c c c c c c} \hline  & & \multicolumn{2}{c}{**Enzyme Assay (With H\({}_{2}\)O\({}_{2}\))**} & \multicolumn{2}{c}{**Enzyme Assay (Without H\({}_{2}\)O\({}_{2}\))**} \\ \cline{3-6}
**Agricultural** & **Protein** & & & **Proable** & **Decase** & **Specific** \\
**Residue** & **Concentration** & **Production** & **Productivity** & **Production** & **Productivity** \\  & & **(U mL\({}^{-1}\))** & **(U mg\({}^{-1}\))** & **(U mL\({}^{-1}\))** & **(U mg\({}^{-1}\))** \\ \hline Sawdust & \(0.028\pm 0.0\)\({}^{\text{a}}\) & \(1.05\pm 0.00\)\({}^{\text{a}}\) & \(37.50\pm 0.00\)\({}^{\text{a}}\) & NAD \({}^{*}\) & NAD \({}^{*}\) \\ Wheat Straw & \(1.023\pm 0.116\)\({}^{\text{b}}\) & \(5.37\pm 0.00\)\({}^{\text{b}}\) & \(5.25\pm 0.00\)\({}^{\text{b}}\) & NAD \({}^{*}\) & NAD \({}^{*}\) \\ Corn Stover & \(1.366\pm 0.021\)\({}^{\text{b}}\) & \(5.13\pm 0.00\)\({}^{\text{b}}\) & \(3.76\pm 0.00\)\({}^{\text{c}}\) & \(1.93\pm 0.53\) & \(1.23\pm 0.21\) \\ \hline \end{tabular} NAD \({}^{*}\)–No Activity Detected. Values with the same superscript letter along the same column are not significantly different (\(p>0.05\)).  
\end{table} 
Table 1: Utilization of some agricultural residues for exoperoxidase production by _Ensifer ahaerens_ NWODO-2. Figure 4: Molecular characterization of peroxidase in _Ensifer alhaaren's_ NWODO-2. (**a**) Gel picture of the polymerase chain reaction (PCR)-amplified product. Lane 1:100 bp DNA ladder, lane 2: Empty, lane 3: PCR-amplified product from _Ensifer alhaaren's_ NWODO-2, lane 4: Negative control. (**b**) Unrooted phylogenetic tree showing the relationship of _Ensifer alhaaren's_ NWODO-2 peroxidase with selected bacterial heme-peroxidase in the PeroxiBase. The percentage of replicate trees in which the associated taxa clustered together in the bootstrap test (1000 replicates) are shown next to the branches.