Methyl chloride utilising bacteria are ubiquitous in the natural environment

Abstract

Enrichment and isolation of methyl chloride utilising bacteria from a variety of pristine terrestrial, freshwater, estuarine and marine environments resulted in the detection of six new methyl chloride utilising Hyphomicrobium strains, strain CMC related to Aminobacter spp. and to two previously isolated methyl halide utilising bacteria CC495 and IMB-1, and a Gram-positive isolate SAC-4 phylogenetically related to Nocardioides spp. All the pristine environments sampled for enrichment resulted in the successful isolation of methyl chloride utilising organisms. ß

Degradation of methyl bromide and methyl chloride in soil microcosms: Use of stable C isotope fractionation and stable isotope probing to identify reactions and the responsible microorganisms

“…This may be because not all cells of a particular strain capable of utilizing methyl halides are active at the same time, with the inactive cells present in the 12 C-fraction, or because the ability of one member of a genus to degrade methyl halides does not mean that all species in the genus are capable of methyl halide degradation. Although Hyphomicrobium chloromethanicum CM2 is able to utilize methyl halides, other Hyphomicrobium strains are not (McAnulla et al, 2001b). Therefore, although similar sequences were found in both 12 C-and 13 C-DNA libraries, they may differ at the species or strain level and the sequences in the 12 C-DNA libraries may represent organisms that are unable to degrade methyl halides.…”

Evidence for the presence of a CmuA methyltransferase pathway in novel marine methyl halide‐oxidizing bacteria

“…Soils are another important sink for methyl halides and recently a number of bacterial strains capable of growth on methyl bromide and methyl chloride have been isolated from a variety of soils (Doronina et al ., 1996;Connell-Hancock et al ., 1998;Coulter et al ., 1999;McAnulla et al ., 2001a). These strains belonged to the genera Methylobacterium , Hyphomicrobium and Aminobacter and used a novel pathway for methyl halide oxidation.…”

“…cmuA encodes the unusual bifunctional methyltransferase/corrinoid-binding enzyme involved in the first step of methyl halide oxidation and this gene has been detected in all extant methyl halide utilizers isolated from the terrestrial environment . cmuA therefore appears to be a good target gene in molecular ecological studies in order to determine the occurrence of methyl halide-oxidizing bacteria in the environment (McAnulla et al ., 2001a;Miller et al ., 2004). Other genes in the vicinity of cmuA have also been implicated in the oxidation of methyl chloride and clusters of chloromethane utilization genes have now been sequenced from several methyl chloride and methyl bromide utilizers (Vannelli et al ., 1999;McAnulla et al ., 2001b;Woodall et al ., 2001;Borodina et al ., 2004).…”

Biodegradability of chlorinated solvents and related chlorinated aliphatic compounds

“…The average rate extrapolated over the land area of the earth accounts for an estimated terrestrial sink of CM of 0.5 Tg y )1 . Strains of aerobic bacteria capable of utilizing CM as a growth substrate have been isolated from a variety of pristine terrestrial, freshwater, estuarine and marine environments (Coulter et al 1999;McAnulla et al 2001). Also anaerobic sludge that was not previously exposed to chloromethanes was capable of degrading CM and DCM (van Eekert et al 1998).…”

“…One research group (Doronina et al 1996;McDonald et al 2001) isolated eight CM-utilizing bacteria belonging to the genera Hyphomicrobium and Methylobacterium from polluted soil at a petrochemical factory. Additionally CM-utilizing bacteria belonging to the genera Rhizobium, Aminobacter and Nocardioides have been isolated from unpolluted environmental samples (Coulter et al 1999;McAnulla et al 2001). Similar to anaerobic growth on CM, the biochemistry of aerobic CMutilization also involves corrinoid-dependent methyltransferases (Coulter et al 1999;McDonald et al 2002).…”