Multispecies plastic associated bacterial community MAGs separation by electromagnetic radiations

Abstract

Plastic is a pollutant that is believed to be difficult to remove from the environment. Most portion of the plastic is a hydrocarbon, which can act as a substrate for the attachment of microorganisms and serves as a source of nutrition for attached microorganisms. We observed and investigated microbial communities developed on in situ incubated low-density polyethylene for 6 months in the ambient marine environment. The plastic degrading microbial community formed was given electromagnetic radiation pretreatment to enhance the recovery of microbial community involved in plastic degradation using shotgun metagenomic sequencing and the probable mechanism of separation of plastic degrading microbial community involving the presence of photoreceptor which sense particular wavelength electromagnetic radiation and activate gene inhibitor. Four different phyla such as Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria have been examined from a total of 62 metagenome-assembled genomes (MAGs). Phylum Proteobacteria was observed to be abundant plastic degrading bacteria; whereas other phyla might be symbiotically associated with proteobacteria in plastic combinely form the plastic associated bacterial community. This is a first report that deals with the community pattern of multispecies plastic degrading bacterial community separated from a substrate by electromagnetic radiations of 650 nm (red light) and 480nm (blue light). Bacterium Piscirickettsiaceae specifically and abundantly (46.57) response to red light whereas bacterium Chromatiaceae specifically and abundantly (16.99) response to blue light. ImportanceIn natural marine environment especially at benthic region, microbes can efficiently degrade plastic by making biofilm on its surface. However this strongly attached biofilm is very much difficult to detach from its substratum. Some people even used high pressure water or scrap using sharp surface in order to remove this biofilm from plastic. However major drawback of using such techniques is we can not recover this biofilm in intact form. In present study we used application of different wavelength electromagnetic radiations in order to recover this biofilm in intact form. It is based on the observation that the bacterial density significantly decreases at higher intensity of light. SynopsisThis study significantly demonstrate strongly attached (on the surface of plastics) plastic degrading marine microbial community composition and function on pretreatment with electromagnetic radiations.