Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient Conditions
Poly-lactic acid (PLA) is increasingly used as a biodegradable alternative to traditional petroleum-based plastics. In this study, we identify a novel agricultural soil isolate of Bacillus pumilus (B12) that is capable of degrading high molecular weight PLA films. This degradation can be detected on...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2019-11-01
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| Series: | Frontiers in Microbiology |
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| Online Access: | https://www.frontiersin.org/article/10.3389/fmicb.2019.02548/full |
| _version_ | 1828520939205165056 |
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| author | Kyle S. Bonifer Xianfang Wen Sahar Hasim Elise K. Phillips Rachel N. Dunlap Eric R. Gann Jennifer M. DeBruyn Todd B. Reynolds |
| author_facet | Kyle S. Bonifer Xianfang Wen Sahar Hasim Elise K. Phillips Rachel N. Dunlap Eric R. Gann Jennifer M. DeBruyn Todd B. Reynolds |
| author_sort | Kyle S. Bonifer |
| collection | DOAJ |
| description | Poly-lactic acid (PLA) is increasingly used as a biodegradable alternative to traditional petroleum-based plastics. In this study, we identify a novel agricultural soil isolate of Bacillus pumilus (B12) that is capable of degrading high molecular weight PLA films. This degradation can be detected on a short timescale, with significant degradation detected within 48-h by the release of L-lactate monomers, allowing for a rapid identification ideal for experimental variation. The validity of using L-lactate as a proxy for degradation of PLA films is corroborated by loss of rigidity and appearance of fractures in PLA films, as measured by atomic force microscopy and scanning electron microscopy (SEM), respectively. Furthermore, we have observed a dose-dependent decrease in PLA degradation in response to an amino acid/nucleotide supplement mix that is driven mainly by the nucleotide base adenine. In addition, amendments of the media with specific carbon sources increase the rate of PLA degradation, while phosphate and potassium additions decrease the rate of PLA degradation by B. pumilus B12. These results suggest B. pumilus B12 is adapting its enzymatic expression based on environmental conditions and that these conditions can be used to study the regulation of this process. Together, this work lays a foundation for studying the bacterial degradation of biodegradable plastics. |
| first_indexed | 2024-12-11T19:39:48Z |
| format | Article |
| id | doaj.art-991db7c70ee046bdb6ad97b3d3cea37b |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-12-11T19:39:48Z |
| publishDate | 2019-11-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-991db7c70ee046bdb6ad97b3d3cea37b2022-12-22T00:53:02ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2019-11-011010.3389/fmicb.2019.02548482387Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient ConditionsKyle S. Bonifer0Xianfang Wen1Sahar Hasim2Elise K. Phillips3Rachel N. Dunlap4Eric R. Gann5Jennifer M. DeBruyn6Todd B. Reynolds7Department of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United StatesDepartment of Biosystems Engineering and Soil Science, Institute of Agriculture, University of Tennessee, Knoxville, Knoxville, TN, United StatesDepartment of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United StatesDepartment of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United StatesDepartment of Biosystems Engineering and Soil Science, Institute of Agriculture, University of Tennessee, Knoxville, Knoxville, TN, United StatesDepartment of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United StatesDepartment of Biosystems Engineering and Soil Science, Institute of Agriculture, University of Tennessee, Knoxville, Knoxville, TN, United StatesDepartment of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United StatesPoly-lactic acid (PLA) is increasingly used as a biodegradable alternative to traditional petroleum-based plastics. In this study, we identify a novel agricultural soil isolate of Bacillus pumilus (B12) that is capable of degrading high molecular weight PLA films. This degradation can be detected on a short timescale, with significant degradation detected within 48-h by the release of L-lactate monomers, allowing for a rapid identification ideal for experimental variation. The validity of using L-lactate as a proxy for degradation of PLA films is corroborated by loss of rigidity and appearance of fractures in PLA films, as measured by atomic force microscopy and scanning electron microscopy (SEM), respectively. Furthermore, we have observed a dose-dependent decrease in PLA degradation in response to an amino acid/nucleotide supplement mix that is driven mainly by the nucleotide base adenine. In addition, amendments of the media with specific carbon sources increase the rate of PLA degradation, while phosphate and potassium additions decrease the rate of PLA degradation by B. pumilus B12. These results suggest B. pumilus B12 is adapting its enzymatic expression based on environmental conditions and that these conditions can be used to study the regulation of this process. Together, this work lays a foundation for studying the bacterial degradation of biodegradable plastics.https://www.frontiersin.org/article/10.3389/fmicb.2019.02548/fullpoly-lactic aciddegradationBacillusregulationassay |
| spellingShingle | Kyle S. Bonifer Xianfang Wen Sahar Hasim Elise K. Phillips Rachel N. Dunlap Eric R. Gann Jennifer M. DeBruyn Todd B. Reynolds Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient Conditions Frontiers in Microbiology poly-lactic acid degradation Bacillus regulation assay |
| title | Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient Conditions |
| title_full | Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient Conditions |
| title_fullStr | Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient Conditions |
| title_full_unstemmed | Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient Conditions |
| title_short | Bacillus pumilus B12 Degrades Polylactic Acid and Degradation Is Affected by Changing Nutrient Conditions |
| title_sort | bacillus pumilus b12 degrades polylactic acid and degradation is affected by changing nutrient conditions |
| topic | poly-lactic acid degradation Bacillus regulation assay |
| url | https://www.frontiersin.org/article/10.3389/fmicb.2019.02548/full |
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