Degradation of aniline and monochloroanilines byRhodococcus sp. An 117 and a pseudomonad: A comparative study

Abstract

Two newly isolated aniline-degrading bacterial strains were characterized with regard to their enzyme systems responsible for aniline catabolism. One of them identified as a Rhodococcus sp. metabolized aniline exclusively via the beta-ketoadipate pathway by means of inducible enzymes. The aniline-degrading enzyme system of the second isolate, presumably a pseudomonad, was shown to consist of an inducible aniline-converting enzyme and constitutive meta-pathway enzymes. Both isolates failed to metabolize monochlorinated anilines in the absence of additional carbon sources. To explain this the ring-cleaving enzymes of both isolates were examined for their substrate specificities. Furthermore, the effect of 4-chlorocatechol on the enzymes catalyzing aniline conversion and catechol oxygenation was investigated.

Efficient biodegradation of chlorophenols in aqueous phase by magnetically immobilized aniline-degrading Rhodococcus rhodochrous strain

“…R. rhodochrous DSM6263 has been isolated as an aniline and monochloroaniline degrader [ 18 ]. It metabolized aniline exclusively via the β-ketoadipate pathway (with catechol as the central metabolite) while failed to metabolize monochlorinated anilines in the absence of additional carbon sources.…”

“…The broth for cultivation (M65) contained 4 g/L yeast extract, 4 g/L glucose and 10 g/L malt extract. The culture temperature was 28 °C and initial pH was set at 7.2 [ 18 ]. All chemicals used in this study were of analytical grade and commercially available.…”

Pseudomonas acidovorans: a bacterium capable of mineralizing 2‐chloroaniline

“…For aniline-pregrown cells of bacteria which only can cometabolize 2-CA it seems rather likely, that the corresponding chlorocatechol is ring-cleaved by the initial enzyme of the ordinary ortho-cleavage pathway, C120 type I (DORN and KNACKMUSS 1978). This is indicated by the activity pattern of such a C120 exhibiting a relative high conversion rate for catechol and strongly reduced for 4-chlorocatechol (KAMINSKI et al 1983). In contrast, increased relative activities with chlorinated catechols, as determined with C 120 of strain CA50, resemble the properties of the corresponding enzyme of the modified ortho-cleavage pathway, C120 type 11, responsible for the degradation of chloroaromatics (DORN andKNACKMUSS 1978, HINTEREGGER et al 1992b).…”

Involvement of the plasmid pPGH1 in the phenol degradation of Pseudomonas putida strain H

“…All methods and conditions used for this purpose were essentially those described in previous papers: (I) respirometric experiments with wholecell suspension [8], (II) preparation of cell-free extracts and determination of specific activities of catechol 2, 3-dioxygenase (EC 1.13.1.2.) and the 2-hydroxymuconic semialdehyde-metabolizing enzyme(s) [12], and (III) preparation of HMS (2-hydroxymuconic semialdehyde)-substrate solutions WI.…”