Cometabolic degradation of polychlorinated biphenyls (PCBs) by axenic cultures of Ralstonia sp. strain SA-5 and Pseudomonas sp. strain SA-6 obtained from Nigerian contaminated soils

Abstract

Substantial metabolism of 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-tetraCB) and 2,3¢,4¢,5-tetraCB by axenic cultures of Ralstonia sp. SA-5 and Pseudomonas sp. SA-6 was observed in the presence of biphenyl supplementation, although, the strains were unable to utilize tetrachlorobiphenyls as growth substrate. The former was more amenable to aerobic degradation (~70% degradation) than the latter (22-45% degradation). Recovery of 2,5-chlorobenzoic acid and chloride from 2,3¢,4¢,5-tetraCB assay is an indication of initial dioxygenase attack on the 3,4-dichlorophenyl ring. The PCB-degradative ability of both strains was also investigated by GC analysis of individual congeners in Aroclor 1242 (100 ppm) following 12-day incubation with washed benzoate-grown cells. Results revealed two different catabolic properties. Whereas strain SA-6 required biphenyl as inducer of the degradation activity, such induction was not required by strain SA-5. Nearly all the detectable congeners in the mixture were extensively degraded (% reduction in ECD area counts for individual congeners ranged from 50.0 to 100% and 14.2 to 100%, respectively, for SA-5 and SA-6). The two strains exhibited no noticeable specificity for congeners with varying numbers of chlorine substitution and positions. The degradative competence of these isolates most especially SA-5 makes them among the most versatile PCB-metabolizing organisms yet reported.

Contrasting microbial community composition and function perspective in sections of a full-scale coking wastewater treatment system

“…Arrows indicate the direction and magnitude of environmental parameters associated with major genera. Each circle represents a subsample of CWW active sludge (A: 1, 2, 3; O 1 : 4, 5, 6; O 2 : 7, 8, 9) (Adebusoye et al 2008) and dimethylsulfide (Arellano-Garcia et al 2009). At the same time, Thiobacillus was found to be responsible for the denitrification (Vishnivetskaya et al 2013).…”

“…The major genera detected in anaerobic active sludge was dominated by Pseudomonas (72.59 %), followed by Alkaliphilus (6.27 %), Comamonas (5.67 %), Campylobacter (1.91 %), and Pusillimonas (1.44 %). It was reported that the genus of Pseudomonas had the ability to degrade quinolone, pyridine, and pyrene (Bai et al 2011a;Deng et al 2012;Zhang et al 2014) and related to the biodegradation of refractory organics (Adebusoye et al 2008) Table S2 and Fig. 4 show the comparison of the major genera.…”

A comprehensive overview of elements in bioremediation

“…It was observed that the consortia derived from anaerobic sludge and amended with electron donors quantitatively and incompletely degraded PCE to cis-dichloroethylene, whereas in reactors augmented with a dehalogenating culture complete dechlorination of PCE occurred even in the presence of additional toxic contaminants. Adebusoye et al (2008) have observed substantial metabolism of 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-tetraCB) and 2,3 0 ,4 0 ,5-tetraCB by axenic cultures of Ralstonia sp. SA-5 and Pseudomonas sp.…”

PCB Association with Model Phospholipid Bilayers

“…There is much interest in environmental contamination from persistent organic pollutants (POPs) due to their pervasiveness in the environment. Studies on the prevalence , and remediation − of molecules such as polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) provide evidence concerning the scope of the POP problem. Several studies on PBBs and PCBs ,− document their environmental persistence and propagation in fish and river sediments.…”