Publication Date:
2018-06-13
Description:
Phenol is particularly toxic and can be found in many environments, in particular in the atmosphere due to its high volatility. It can be emitted directly from manufacturing processes or natural sources, and it can also result from benzene oxidation. Although phenol biodegradation by microorganisms has been studied in many environments, the cloud medium has not been investigated yet as the discovery of active microorganisms in cloud is rather recent. The main objective of this work was to evaluate the potential degradation of phenol by cloud microorganisms. Phenol concentrations were measured by GC-MS on five cloud samples collected at the PUY station: they ranged from 0.15 to 0.74µgL−1. The strategy for investigating its potential biodegradation involved a metatranscriptomic analysis and metabolic screening of bacterial isolates from cloud water collected at the PUY station (summit of puy de Dôme , 1465ma.s.l., France) for phenol degradation capabilities. Among prokaryotic messenger RNA enriched metatranscriptomes obtained from 3 cloud water samples, we detected transcripts of genes coding for enzymes involved in phenol degradation (phenol monooxygenases and phenol hydroxylases) and its main degradation product, catechol (catechol 1.2-dioxygenases). These enzymes were likely from Gamma-Proteobacteria, a dominant class in clouds, more specifically the genera Acinetobacter and Pseudomonas. Bacterial isolates from cloud water samples (Pseudomonas spp., Rhodococcus spp. and strains from the Moraxellaceae family) were screened for their ability to degrade phenol: 93% of the 145 strains tested were positive. These findings highlight the possibility of phenol degradation by microorganisms in clouds.
Print ISSN:
1810-6277
Electronic ISSN:
1810-6285
Topics:
Biology
,
Geosciences
