Separation of a phenol carboxylating organism from a two-member, strict anaerobic co-culture

Abstract

In a culture converting phenol to benzoic acid under anaerobic conditions and previously described as being constituted of only a Clostridium-like strain 6, another bacterium (strain 7) was observed. Each organism was enriched by centrifugation on a Percoll gradient. Strain 6 was purified by dilution and plating. Strain 7 did not grow on solid media, but a strain 7 culture, cleared of strain 6, was obtained by subculturing in the presence of ampicillin and by dilution. In fresh medium, phenol was transformed by the reconstituted co-culture but not by each strain alone. In a supernatant from a co-culture or from a strain 6 culture, strain 7 alone transformed phenol but not strain 6. Maintenance of an active strain 7 in fresh medium instead of co-culture supernatant became possible when phenol was replaced by 4-hydroxybenzoate (4-OHB), which is decarboxylated to phenol before being transformed to benzoate. Even with 4-OHB, the use of co-culture (or strain 6 culture) supernatant resulted in faster transformation activity and growth rate. A phylogenetic analysis placed strain 7 in a cluster of uncultivated or nonisolated bacteria (92-96% homology). Strain 7 is also related to Desulfotomaculum, Desulfitobacterium, Desulfosporosinus, Moorella, and Sporotomaculum genera (87-92% homology).

Performance and microbial community composition in a long-term sequential anaerobic-aerobic bioreactor operation treating coking wastewater

“…Soehngenia, the second most abundant anaerobic bacterium in this study, was previously reported to degrade benzaldehyde (Parshina et al 2003), an intermediate in anaerobic phenol degradation (Sharma and Philip 2015). Hydrolytic fermentative acidogenic activity in anaerobic bioreactors is likely controlled by strict anaerobic bacteria like Longilinea, Clostridium, and Proteiniphilum (Yamada et al 2007;Kohda et al 1997;Letowski et al 2001;Chen and Dong 2005;Larsen et al 2009) and facultative aerobic bacteria such as Corynebacterium (Kampfer et al 2009). In the aerobic sludge, the high abundances of Thiobacillus, Comamonas, Diaphorobacter, Ottowia, and Weeksella (Table S8), which reportedly degrade several phenol and SCN − compounds (Felföldi et al 2010;Beller et al 2006;Klankeo et al 2009;Yuste et al 2000), were in accordance with the significant removal of pollutants in the final effluent.…”

Identification and Isolation of Anaerobic, Syntrophic Phthalate Isomer-Degrading Microbes from Methanogenic Sludges Treating Wastewater from Terephthalate Manufacturing

“…Importantly, the methanogenic phthalate isomer-degrading syntrophic consortia reported by Kleerebezem et al (14), in which sporeformers were observed as the major populations, were also shown to have no ability to utilize sulfate; these traits strongly suggest that the bacterial populations in the enrichments were likely to be similar to the ones we identified as members of subcluster Ih. Recently, strain 7, which is also a member of subcluster Ih in 'Desulfotomaculum lineage I', was purified from a phenol-degrading anaerobic culture and showed the ability to metabolize phenol (17). In addition, a number of environmental clones belonging to subcluster Ih can be found in the public databases, some of which were retrieved from anaerobic petroleum-contaminated sites (7).…”

Non-Sulfate-Reducing, Syntrophic Bacteria Affiliated with Desulfotomaculum Cluster I Are Widely Distributed in Methanogenic Environments

“…With the exception of Cryptanaerobacter phenolicus (24), all previously isolated strains and cultures of subcluster Ih obtained in this study showed this unique phenotype, although the range of degradable substrates differed among strains/cultures. The physiology of the phenol degrader C. phenolicus (previously known as strain 7) has not been fully examined, and thus, it is currently unknown whether this strain can perform syntrophic substrate oxidation in cooperation with hydro- genotrophic microbes (24,31). Given their recognized phenotypes and wide occurrence in low-sulfate, methanogenic environments, descendants of the Desulfotomaculum subcluster Ih branch most likely function as non-sulfate-reducing, syntrophic degraders of organic substrates in situ.…”