{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T15:48:25Z","timestamp":1791820105611,"version":"4.3.4"},"reference-count":37,"publisher":"American Chemical Society (ACS)","issue":"10","license":[{"start":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T00:00:00Z","timestamp":1790467200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T00:00:00Z","timestamp":1790467200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T00:00:00Z","timestamp":1790467200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"name":"Department of Energy","award":["NFE-24-10496"],"award-info":[{"award-number":["NFE-24-10496"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Protein engineering has recently emerged as a promising strategy for enhancing the enzymatic recycling of bio-based polymers with the aim of replacing non-degradable petroleum-based plastics with biodegradable ones like poly-l-lactic acid (PLLA). However, a significant challenge exists in the evaluation of the biodegradation efficiency of newly developed enzymes. The precise tracking and continuous rate monitoring of the enzyme-catalyzed hydrolysis remain difficult to achieve with a conventional l-lactate assay kit, which provides only endpoint measurements and is therefore decoupled from the real-time degradation process. To address this issue, we introduce a novel Fo\u0308rster Resonance Energy Transfer (FRET)-based PLLA substrate capable of monitoring real-time PLLA degradation. This was achieved by connecting a highly fluorescent amino carbamoyl coumarin (ACC) dye with a quencher (2,4-dinitrophenyl-l-lysine) via a tetrameric oligo-l-lactate chain. Several fluorescence studies demonstrate that this substrate can effectively detect PLLA-degrading enzyme activity by monitoring increased fluorescence due to enzyme-catalyzed hydrolysis of the oligolactate chain and disruption of the intramolecular FRET system. This substrate can be a potent replacement for the conventional l-lactate assay kit as it allows fast and accurate tracking of the enzyme activity toward PLLA.<\/jats:p>","DOI":"10.1021\/acs.biomac.6c01709","type":"journal-article","created":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T08:01:40Z","timestamp":1790496100000},"page":"6998-7006","source":"Crossref","is-referenced-by-count":0,"title":["A FRET-Based Fluorometric Assay for Tracking the Enzymatic Degradation of Poly-\n                    <scp>l<\/scp>\n                    -Lactic Acid"],"prefix":"10.1021","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-3731-7388","authenticated-orcid":true,"given":"Mahbub","family":"Ullah","sequence":"first","affiliation":[{"name":"University of Tennessee , , , ,","place":["Knoxville, Tennessee, United States, 37996"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5425-4194","authenticated-orcid":true,"given":"Jordan A.","family":"Cannon","sequence":"additional","affiliation":[{"name":"University of Tennessee , , , ,","place":["Knoxville, Tennessee, United States, 37996"]},{"name":"Circular Biosciences LLC , , ,","place":["Knoxville, Tennessee, United States, 37919"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2867-7182","authenticated-orcid":true,"given":"Todd B.","family":"Reynolds","sequence":"additional","affiliation":[{"name":"University of Tennessee , , , ,","place":["Knoxville, Tennessee, United States, 37996"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8737-5910","authenticated-orcid":true,"given":"Michael D.","family":"Best","sequence":"additional","affiliation":[{"name":"University of Tennessee , , , ,","place":["Knoxville, Tennessee, United States, 37996"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,27]]},"reference":[{"key":"2026101210565099800_cit1","doi-asserted-by":"publisher","first-page":"803","DOI":"10.1126\/science.297.5582.803","article-title":"Biodegradable Polymers for the Environment","volume":"297","author":"Gross","year":"2002","journal-title":"Sci."},{"key":"2026101210565099800_cit2","doi-asserted-by":"publisher","first-page":"50","DOI":"10.1002\/anie.201805766","article-title":"Plastics of the Future? 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