Burkholderiales participating in pentachlorophenol biodegradation in iron-reducing paddy soil as identified by stable isotope probing

Abstract

As the most prevalent preservative worldwide for many years, pentachlorophenol (PCP) has attracted much interest in the study of biodegradation in soil and aquatic ecosystems. However, the key microorganisms involved in anaerobic degradation are less well understood. Hence, we used DNA-based stable isotope probing (SIP) to identify the PCP-degrading microorganisms in iron-rich paddy soil under anaerobic conditions. (12)C- and (13)C-labeled PCP were almost completely degraded in 30 days under iron-reducing conditions. The results of terminal restriction fragment length polymorphism (T-RFLP) of 16S rRNA genes showed that 197 and 217 bp (HaeIII digests) restriction fragments (T-RFs) were enriched in heavy DNA fractions of (13)C-labeled samples, and the information from 16S rRNA gene clone libraries suggested that the microorganisms corresponding to these T-RF fragments, which increased in relative abundance during incubation, belonged to the order of Burkholderiales, in which 197 and 217 bp were classified as unclassified Burkholderiales and the genus Achromobacter, respectively. The results of the present study indicated that Burkholderiales-affiliated microorganisms were responsible for PCP degradation in anaerobic paddy soil and shed new light on in situ bioremediation in anaerobic PCP contaminated soil.

Insights into interactions between vanadium (V) bio-reduction and pentachlorophenol dechlorination in synthetic groundwater

“…Interestingly, phenol concentration deceased in the later stages ( Fig. 2c), consistent with previous studies [43], showing that chlorophenols were ring-cleaved, and phenol acted as a supplementary carbon source for heterotrophs to realize partial mineralization of PCP through co-metabolism [55]. Solution pH increased slightly within the 7 d operation, which might be induced by proton consumption in microbial V(V) reduction and PCP anaerobic dechlorination [56].…”

“…The primer sets were as follows: napA V17F [42]; this was due to the strong toxicity of co-existing PCP in B-V/P. However, PCP removal efficiency in B-V/P was comparable to previously reported results, where approximately 50% of PCP was removed after 10 days by microbes in soil with initial PCP concentration of 8 mg/L [43]. In reported contaminated aquifers, PCP concentrations (around 0.1 mg/L) were much lower than V(V) (9.66 mg/L) [44,45], therefore, both V(V) and PCP could be efficiently removed by the proposed bioprocess.…”

Different fertilization treatments in coal mining-affected soils change bacterial populations and enable soil reclamation

“…The abundance of Burkholderiales increased rapidly after 1 year of reclamation and decreased significantly to the same abundance as in FS after 5 years. They were found to participate in pentachlorophenol biodegradation in iron-reducing paddy soil and as a degrader of 3-hydroxybutyrate-co-3-hydroxyhexanoate (PHBH) films in biofilm functions (Tong et al 2015;Morohoshi et al 2018).The abundance of Rhodospirillales in the 5-year group was higher than in the 1-year group. These organisms have extreme metabolic versatility encompassing photoheterotrophic, chemoorganotrophic, and photoautotrophic lifestyles, and could potentially adapt well to extremely oligotrophic areas and benefit from higher productivity (King et al 2010;Ding et al 2018).…”

Remediation of phthalates in river sediment by integrated enhanced bioremediation and electrokinetic process

“…The remaining six strains (i.e., Herminiimonas sp., Zoogloea sp., Naxibacter sp., Massilia sp Actinobacterium, Burkholderiales, and Duganella sp.) have been reported for degradation of other organic contaminants (Li et al, 2005;Kim et al, 2010Kim et al, , 2013Bajaj et al, 2012;Liu et al, 2014;Tong et al, 2015). Although there is no relevant literature showing these strains could degrade PAEs at the present time, however, these strains persistently exist in the environmental media contaminated by PAEs, gradually domesticated and evolved into species that could degrade contaminants in the environment (Wang et al, 2010).…”