Gene redundancy of two-component (chloro)phenol hydroxylases inRhodococcus opacus1CP

Abstract

Among other factors, a distinct gene redundancy is discussed to facilitate high metabolic versatility of rhodococci. Rhodococcus opacus 1CP is a typical member in that respect and degrades a multitude of (chlorinated) aromatic compounds. In contrast to the central pathways of aromatic degradation in strain 1CP, little is known about the degree of gene redundancy and to what extent this is reflected on protein level within the steps of peripheral degradation. By means of degenerated primers deduced from tryptic peptides of a purified phenol hydroxylase component and using the amplified fragment as a labelled probe against genomic 1CP-DNA, three gene sets encoding three different two-component phenol hydroxylases pheA1/pheA2(1-3) could be identified. One of them was found to be located on the megaplasmid p1CP, which confirms the role of these elements for metabolic versatility. Protein chromatography of phenol- and 4-chlorophenol-grown 1CP-biomass gave first evidences on a functional expression of these oxygenases, which could be initially characterised in respect of their substrate specificity.

Catabolism of alkylphenols inRhodococcusvia ameta-cleavage pathway associated with genomic islands

“…), as reported for 297PheA2(Gröning et al, 2014;Saa et al, 2010;Straube, 1987). 298Annotation of additional genes299During growth of EP4 on 4-ethylphenol, phenol hydroxylase genes, pheA and pheB, adjacent to 300 the cat gene cluster, were additionally upregulated (Figure 2B, Supplementary Figure 3).…”

“…was previously 322 annotated as an aromatic ring hydroxylase possibly involved in steroid degradation(McLeod et 323 al., 2006) and there were three previously-identified pheA homologs (Supplementary Table 4) 324(Gröning et al, 2014). Local alignment of the 13 Aph proteins against proteins predicted from all 325 325 Rhodococcus genomes identified 75 strains with full or partial (≥7 genes) putative Aph 326 pathways, including RHA1 (SupplementaryFigure 5A).…”

Catalytic and hydrodynamic properties of styrene monooxygenases from Rhodococcus opacus 1CP are modulated by cofactor binding

“…Thus, in strain 1CP, both the styA1/styA2B gene cluster and the newly discovered styABCD -cluster might be regulated differently compared to that found for Pseudomonas species (Alonso et al 2003 ; Oelschlägel et al 2014 ). The presence of three StyA isoenzymes in a single strain is new and underlines the gene redundancy of rhodococci (Gröning et al 2014a ; Patrauchan et al 2005 ). The different gene cluster organization as well as the respective regulatory machinery might indicate a convergent evolution (Tischler et al 2012 ).…”

Catabolism of Phenol and Its Derivatives in Bacteria

“…The substrate specificities of these paralogous isoenzymes were analyzed in R. opacus 1CP, and the importance of redundancy of this enzyme for high metabolic capacity of this strain was discussed (Gr€ oning et al, 2014). Differences in the transcriptional regulation of two clusters encoding paralogous two-component PHs in Rhodococcus jostii RHA1 were also observed (Sz€ ok€ ol et al, 2014).…”