Pseudomonasisolates degrade and form biofilms on polyethylene terephthalate (PET) plastic

Abstract

Bioaugmentation is a possible remediation strategy for the massive amounts of plastic waste in our oceans and landfills. For this study, soil samples were collected from petroleum polluted locations in the Houston, Texas area to isolate microorganisms capable of plastic degradation.Bacteria were propagated and screened for lipase activity, which has been associated with the bacterial degradation of some plastics to date. We identified three lipase-positive Pseudomonas species, and Bacillus cereus as part of two consortia, which we predict enhances biofilm formation and plastic degradation. Lipase-positive consortia bacteria were incubated alongside blank and E.coli controls with UV-irradiated polyethylene terephthalate (PET), high-density polyethylene (HDPE), or low-density polyethylene (LDPE) as sole sources of carbon. Surface degradation of PET plastic was quantified by changes in molecular vibrations by infrared spectroscopy. The bacteria formed biofilms on PET, observed by scanning electron microscopy, and induced molecular changes on the plastic surface, indicating the initial stages of plastic degradation. We also found molecular evidence that one of the Pseudomonas isolates degrades LDPE. To date, lipase positive Pseudomonas spp. degradation of PET has not been well described, and this work highlights the potential for using consortia of common soil bacteria to degrade plastic waste.

UV Pretreatment Impairs the Enzymatic Degradation of Polyethylene Terephthalate

“…Nevertheless, only colonization of Ideonella sakaiensis on amorphous PET materials has been evidenced so far in correlation with a notable polymer degradation (Yoshida et al, 2016). More recently, another study speculated that microbial biofilm formation might be more pronounced on PET materials exposed to UV radiation for 30 min (Vague et al, 2019). However, the biodegradation of PET could not be unambiguously verified by either demonstrating the release of degradation products or by a significant weight loss.…”

The Impact of Bacteria of the Genus Bacillus upon the Biodamage/Biodegradation of Some Metals and Extensively Used Petroleum-Based Plastics

“…Strains B. subtilis and B. cereus formed biofilm on PET and poly (lactic acid), demonstrating biochemical activity and accelerating biodegradation of both plastic materials [64]. B. cereus was also identified as part of two consortia capable of biofilm formation and PET degradation [65]. B. megaterium formed a biofilm on PET film [28].…”

Isolation, characterization and optimization of bacterial isolate SARR1 for biodegradation of pretreated low density polyethylene

“…After the primary screening, secondary screening was done to confirm the degradation of LDPE by the isolated bacteria using different types of polyethylene biodegradability tests, i.e. Sturm test (CO 2 evolution) (Esmaeili et al, 2013), triphenyl tetrazolium chloride (TTC) test (Wolinska et al, 2016, Kumari et al, 2019, and microbial adhesion to hydrocarbons test (MATH) (Vague et al, 2019).…”