Bacterial Biotransformation of Pentachlorophenol and Micropollutants Formed during Its Production Process

Abstract

Pentachlorophenol (PCP) is a toxic and persistent wood and cellulose preservative extensively used in the past decades. The production process of PCP generates polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) as micropollutants. PCDD/Fs are also known to be very persistent and dangerous for human health and ecosystem functioning. Several physico-chemical and biological technologies have been used to remove PCP and PCDD/Fs from the environment. Bacterial degradation appears to be a cost-effective way of removing these contaminants from soil while causing little impact on the environment. Several bacteria that cometabolize or use these pollutants as their sole source of carbon have been isolated and characterized. This review summarizes current knowledge on the metabolic pathways of bacterial degradation of PCP and PCDD/Fs. PCP can be successfully degraded aerobically or anaerobically by bacteria. Highly chlorinated PCDD/Fs are more likely to be reductively dechlorinated, while less chlorinated PCDD/Fs are more prone to aerobic degradation. The biochemical and genetic basis of these pollutants' degradation is also described. There are several documented studies of effective applications of bioremediation techniques for the removal of PCP and PCDD/Fs from soil and sediments. These findings suggest that biodegradation can occur and be applied to treat these contaminants.

Cyclodextrin-Based Polymer-Supported Bacterium for the Adsorption and in-situ Biodegradation of Phenolic Compounds

“…In Figure 3a , the observed increase in absorbance relates to the formation of various PCP metabolites such as DCHQ and TCBQ, as described elsewhere (Ling et al, 2016 ). The degradation pathway of chlorophenols and other quinones to intermediates/byproducts such as DCHQ and TCBQ with the use of SpC and other microorganisms have been reported (Arora and Bae, 2014 ; Lopez-Echartea et al, 2016 ). Herein, the PCP metabolic by-products were monitored according to the measurement of absorbance values (λ max = 340 nm).…”

“…By contrast, biological treatment of soil and water using injectable/infusible bacterial microorganisms offers a clean and sustainable bioremediation strategy for PCP (Banat, 1995 ). The biodegradation of chlorophenols by various microorganisms such as Pseudomonas sp., Sphingomonas sp., Alcaligenes sp., and Sphingobium Chlorophenolicum have been reported (Olaniran and Igbinosa, 2011 ; Arora and Bae, 2014 ; Lopez-Echartea et al, 2016 ). In particular, the mechanism and metabolic pathway for the biodegradation of PCP and its derivatives using Sphingobium Chlorophenolicum (SpC) have also been studied (Copley et al, 2012 ; Arora and Bae, 2014 ).…”

Nghiên Cứu Phân Lập Một Số Chủng Vi Khuẩn Từ Đất Nhiễm Dioxin Ở a Lưới, Thừa Thiên Huế

“…Gần đây, phương pháp xử lý sinh học bằng thực vật, vi khuẩn và vi nấm được đề xuất và nhận được nhiều quan tâm của các nhà nghiên cứu trên thế giới do khả năng phân hủy mạnh cấu trúc dioxin và các hợp chất tương tự dioxin, qua đó loại bỏ độc tính của chúng [3,6,16,18]. Nhiều vi sinh vật đất được thông báo có khả năng phân hủy dioxin như Janibacter terrae [11], Comamonas sp.…”

Genomic analysis of dibenzofuran-degradingPseudomonas veroniistrain Pvy reveals its biodegradative versatility

“…Rieske non-heme iron dioxygenases are generally responsible for catalyzing the first reaction in the aerobic degradation pathway of aromatic POPs, which is followed by cleaving dioxygenases involved in the opening of the aromatic ring ( Hiraishi 2003 ; Field and Sierra-Alvarez 2008 ; Lopez-Echartea et al 2016 ). The aim of this study was to analyze the genome of Pseudomonas veronii strain Pvy, which was isolated through its ability to degrade dibenzofuran (DF), with respect to aromatic ring-hydroxylating dioxygenases (ARHD) and other enzymes responsible for the biodegradative versatility of the strain.…”