Into the Plastisphere, Where Only the Generalists Thrive: Early Insights in Plastisphere Microbial Community Succession

Abstract

The ubiquity of plastic debris in marine environments raises the question, what impacts do plastics have on our marine microbiota? To investigate this, we applied bacterial 16S rRNA gene and fungal ITS2 region sequencing to identify changes in microbial biofilm community compositions on marine plastic, over time. We sampled biofilm on virgin linear low-density polyethylene (LLDPE), nylon-6 (PA) and glass after 2, 6 and 12 weeks of constant immersion in Te Whakaraupō-Lyttelton Harbour, Aotearoa-New Zealand. Of the prokaryotes, Proteobacteria and Bacteroidetes were predominant in all samples and Verrucomicrobiota were most abundant in mature biofilms. Microbial communities on the three substrate types were significantly distinct from those in the surrounding seawater, regardless of age, but not between attachment substrates. Bacterial communities occurring two weeks after immersion and fungal communities at six weeks were found to vary more among substrate types than at other times; however, no significant substrate-specific communities were identified overall. Taxa closely related to previously reported plastic-biodegrading species were found in very low abundance across all substrates, including on the glass slides. Our findings suggest that microorganisms do not selectively persist on the LLDPE or PA surfaces to gain significant direct metabolic benefit, instead using these plastics primarily as an attachment surface on which they form generalist biofilm communities.

Year-Long Microbial Succession on Microplastics in Wastewater: Chaotic Dynamics Outweigh Preferential Growth

“…While fungal biofilms demonstrated this same pattern of chaotic succession up to 6 months as in 16S rDNA, the 12-month fungal data shows an, albeit small (6% average similarity), increase in similarity between 6-12 months, indicating that this chaotic drift seen in samples, at least regarding fungal communities, reaches an endpoint. Interestingly, these findings are generally similar to those by Wallbank et al [75], who also examined MP bacterial and fungal biofilm succession over time, albeit in seawater between 2 and 12 weeks. They demonstrated the highest similarity at the first time point, comparable for both bacteria and fungi, and also saw complete shifts in bacterial communities over time while seeing less fundamental shifts with more overlap in fungal communities, all of which is similar to what was observed within our study.…”

Does plastic type matter? Insights into non-indigenous marine larvae recruitment under controlled conditions

“…The sonicate solution was centrifuged (4,500 × g , 10 min, 4 °C). Supernatants were gently decanted and discarded, followed by an additional 5 min centrifugation step and removal of the remaining supernatant with a pipette ( Wallbank et al, 2022 ).…”

“…In 2013, Zettler, Mincer & Amaral-Zettler (2013) coined the term “Plastisphere” to characterize the diverse microbial assemblages of organisms attached to plastic surfaces. This pioneering publication triggered numerous investigators to characterize microbial communities inhabiting the plastisphere, including bacteria ( Zettler, Mincer & Amaral-Zettler, 2013 ; Frère et al, 2018 ), fungi ( Lacerda et al, 2020 ), diatoms ( Cheng et al, 2021 ), putative pathogens ( Kirstein et al, 2016 ; Viršek et al, 2017 ), and potential plastic degraders ( Erni-Cassola et al, 2020 ; Wallbank et al, 2022 ). However, despite remarkable advances in characterizing the micro-plastisphere on various polymer types, little is known regarding the mechanisms involved in macro-plastisphere community succession and the factors influencing the recruitment of macro-invertebrates, especially NIS larvae and propagules.…”

Engineering a microbiosphere to clean up the ocean – inspiration from the plastisphere

“…Many of the members of the plastisphere community are bacterial species but also include other types of microorganisms such as archaea, fungi and microbial eukaryotes (Oberbeckmann et al, 2014;Oberbeckmann et al, 2016;Oberbeckmann et al, 2018). For a comprehensive list of species associated with plastispheres, refer to Wallbank et al, (2022). Two main groups of microorganisms, known as the photoautotrophs e.g.…”

“…diatoms (Mastogloia, Navicula, Nitzschia), cyanobacteria (Phormidium, Rivularia, and Leptolyngbya) and heterotrophs, e.g. bacteria (Pseudomonas, Azotobacter, Bacillus), are typically encountered in plastisphere communities (Dey et al, 2022;Wallbank et al, 2022). The co-cultivation and coexistence of these organisms within a microbiosphere could be achieved with a symbiotic arrangement of these species (Zuñiga et al, 2020).…”