{"id":102574,"date":"2022-01-07T07:26:00","date_gmt":"2022-01-07T06:26:00","guid":{"rendered":"https:\/\/renewable-carbon.eu\/news\/?p=102574"},"modified":"2022-01-04T13:17:57","modified_gmt":"2022-01-04T12:17:57","slug":"plastic-degrading-enzymes-correlate-with-pollution","status":"publish","type":"post","link":"https:\/\/renewable-carbon.eu\/news\/plastic-degrading-enzymes-correlate-with-pollution\/","title":{"rendered":"Plastic-degrading enzymes correlate with pollution"},"content":{"rendered":"\n

<\/h2>\n\n\n\n\n\n

The number of microbial enzymes with the ability to degrade plastic is growing, in correlation with local levels of plastic pollution. That is the finding of a new study from Chalmers that measured samples of environmental DNA from around the globe. The results illustrate the impact plastic pollution is having on the environment, and hint at potential new solutions for managing the problem.\u200b<\/strong><\/p>\n\n\n\n

\u200bThe problems of global plastic pollution are all too widespread, as mass-production of plastic has exploded in the last 70 years or so \u2013 from around 2 million tonnes per year to around 380 million. This has given sufficient evolutionary time for various microbes present in the environment to respond to these compounds, and many different enzymes have been discovered in previous studies with the ability to degrade different plastics.<\/p>\n\n\n\n

\"Aleksej
Aleksej Zelezniak \/ Photo: Martina Butorac<\/figcaption><\/figure><\/div>\n\n\n\n

The new study<\/a>, recently published in the scientific journal mBIO<\/em>, analysed samples of environmental DNA from hundreds of locations around the world. The researchers used computer modelling to search for microbial enzymes with plastic-degrading potential, which was then cross-referenced with the official numbers for plastic waste pollution across countries and oceans.<\/p>\n\n\n\n

\u201cUsing our models, we found multiple lines of evidence supporting the fact that the global microbiome’s plastic-degrading potential correlates strongly with measurements of environmental plastic pollution \u2013 a significant demonstration of how the environment is responding to the pressures we are placing on it,\u201d says Aleksej Zelezniak<\/strong>, Associate Professor in Systems Biology at Chalmers.<\/p><\/blockquote>\n\n\n\n

More enzymes in the most polluted areas<\/h3>\n\n\n\n

In other words, the quantity and diversity of plastic-degrading enzymes is increasing, in direct response to local levels of plastic pollution. In total, over 30,000 enzyme \u2018homologues\u2019 were found with the potential to degrade 10 different types of commonly used plastic. Homologues are members of protein sequences sharing similar properties. Some of the locations that contained the highest amounts were notoriously highly polluted areas, for example samples from the Mediterranean Sea and South Pacific Ocean.<\/p>\n\n\n\n

\"Jan
Jan Zrimec \/ Photo: Matej Kolakovic<\/figcaption><\/figure><\/div>\n\n\n\n

\u201cCurrently, very little is known about these plastic-degrading enzymes, and we did not expect to find such a large number of them across so many different microbes and environmental habitats. This is a surprising discovery that really illustrates the scale of the issue,\u201d explains Jan Zrimec<\/strong>, first author of the study and former post-doc in Aleksej Zelezniak\u2019s group, now a researcher at the National Institute of Biology in Slovenia.<\/p><\/blockquote>\n\n\n\n

Potential value for fighting the global plastic crisis<\/h3>\n\n\n\n

Every year around 8 million tonnes of plastic escapes into the world\u2019s oceans. The natural progresses for plastic degradation are very slow \u2013 the lifetime of a PET-bottle, for example, can be up to hundreds of years. The growth and accumulation of plastic waste in the oceans and on land is a truly global problem and there is an increasing need for solutions to manage this waste. The researchers believe that their results could potentially be used to discover and adapt enzymes for novel recycling processes.<\/p>\n\n\n\n

\u201cThe next step would be to test the most promising enzyme candidates in the lab to closely investigate their properties and the rate of plastic degradation they can achieve. From there you could engineer microbial communities with targeted degrading functions for specific polymer types,\u201d explains Aleksej Zelezniak<\/strong>.<\/p><\/blockquote>\n\n\n\n

The article, Plastic-Degrading Potential across the Global Microbiome Correlates with Recent Pollution Trends, is published in the journal mBio<\/em>. It was written by Jan Zrimec, Mariia Kokina, Sara Jonasson, Francisco Zorrilla and Aleksek Zelezniak.<\/p>\n\n\n\n

Contact<\/h3>\n\n\n\n

Aleksej Zelezniak, Associate Professor
Department of Biology and Biological Engineering, Chalmers
Tel: +46 31 772 81 71
E-mail: aleksej.zelezniak@chalmers.se<\/a><\/p>\n\n\n\n

\u200b<\/p>\n\n\n\n

More evidence of a connection from comparing land and sea<\/h3>\n\n\n\n
  • The researchers compiled a data set of 95 previously known enzymes with plastic-degrading or modifying capability. They then used \u2018Hidden Markov Models\u2019 to search through data taken from some of the largest global metagenomic studies to identify homologous sequences from 236 locations. The researchers used samples of the internal human microbiome as a control for false positives \u2013 no plastic-degrading enzymes have as yet been identified within humans, despite concerns of microplastic-ingestion.<\/li>
  • They identified a total of around 30,000 enzyme hits, circa 12,000 in the ocean microbiome and 18,000 in the soil, corresponding to 10 major commercial plastics, including 6 polymers and 4 additives. Nearly 60% of the identified plastic-degrading enzymes did not map to any known enzyme classes, suggesting that the researchers uncovered novel plastic-degrading functional content.<\/li><\/ul>\n\n\n\n

    \u200bMore information about how the researchers catalogued the enzymes<\/h3>\n\n\n\n
    • The researchers compiled a data set of 95 previously known enzymes with plastic-degrading or modifying capability. They then used \u2018Hidden Markov Models\u2019 to search through data taken from some of the largest global metagenomic studies to identify homologous sequences from 236 locations. The researchers used samples of the internal human microbiome as a control for false positives \u2013 no plastic-degrading enzymes have as yet been identified within humans, despite concerns of microplastic-ingestion.<\/li>
    • They identified a total of around 30,000 enzyme hits, circa 12,000 in the ocean microbiome and 18,000 in the soil, corresponding to 10 major commercial plastics, including 6 polymers and 4 additives. Nearly 60% of the identified plastic-degrading enzymes did not map to any known enzyme classes, suggesting that the researchers uncovered novel plastic-degrading functional content.<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"

      The number of microbial enzymes with the ability to degrade plastic is growing, in correlation with local levels of plastic pollution. That is the finding of a new study from Chalmers that measured samples of environmental DNA from around the globe. The results illustrate the impact plastic pollution is having on the environment, and hint […]<\/p>\n","protected":false},"author":59,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","nova_meta_subtitle":"Microbes across the globe are evolving to eat the plastic pollution","footnotes":""},"categories":[5572],"tags":[6406,5840,12615,11966],"supplier":[8249],"class_list":["post-102574","post","type-post","status-publish","format-standard","hentry","category-bio-based","tag-environment","tag-enzymes","tag-microbes","tag-plastics","supplier-chalmers-university-of-technology"],"_links":{"self":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/102574","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/users\/59"}],"replies":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/comments?post=102574"}],"version-history":[{"count":0,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/102574\/revisions"}],"wp:attachment":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/media?parent=102574"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/categories?post=102574"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/tags?post=102574"},{"taxonomy":"supplier","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/supplier?post=102574"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}