Every year up to 12 000 tonnes of plastics enter our oceans. As the plastics are not made to degrade easily, all this plastic pollution is piling up. PhD student Astrid Rombouts, recently graduated dr. Valérie Mattelin and post-doc dr. Josefien Van Landuyt wondered how certain bacteria, like Alcanivorax, can help break down plastics in the marine environment. This study focused on three types of plastics: PHBH, nylon 6/69, and a newly developed plastic called B4PF01. They investigated how Alcanivorax interacts with these materials during the early stages of colonization.

Initial tests showed that Alcanivorax made up a large portion of the microbial community on plastics, with up to 58.8% abundance after a year of enrichment. Further experiments revealed that Alcanivorax grew most successfully on whole plastic samples compared to plastic fragments or leachable compounds. Nylon 6/69 was particularly favorable, supporting a community where Alcanivorax reached 62.7% abundance.

They also isolated two specific strains of Alcanivorax that are closely related to known species, A. borkumensis SK2 and Alcanivorax sp. DG881. These strains showed strong growth and activity on plastics when studied individually, aligning with their behavior in larger microbial communities.

This study highlights the potential of Alcanivorax to contribute to the breakdown of certain plastics, particularly nylon 6/69. These findings improve our understanding of how bacteria can play a role in reducing plastic pollution and support future efforts in bioremediation!