Lipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversion
Abstract Background Lignin is a recalcitrant aromatic polymer that is a potential feedstock for renewable fuel and chemical production. Rhodococcus opacus PD630 is a promising strain for the biological upgrading of lignin due to its ability to tolerate and utilize lignin-derived aromatic compounds....
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2018-12-01
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| Series: | Biotechnology for Biofuels |
| Subjects: | |
| Online Access: | http://link.springer.com/article/10.1186/s13068-018-1337-z |
| _version_ | 1818232196881711104 |
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| author | William R. Henson Fong-Fu Hsu Gautam Dantas Tae Seok Moon Marcus Foston |
| author_facet | William R. Henson Fong-Fu Hsu Gautam Dantas Tae Seok Moon Marcus Foston |
| author_sort | William R. Henson |
| collection | DOAJ |
| description | Abstract Background Lignin is a recalcitrant aromatic polymer that is a potential feedstock for renewable fuel and chemical production. Rhodococcus opacus PD630 is a promising strain for the biological upgrading of lignin due to its ability to tolerate and utilize lignin-derived aromatic compounds. To enhance its aromatic tolerance, we recently applied adaptive evolution using phenol as a sole carbon source and characterized a phenol-adapted R. opacus strain (evol40) and the wild-type (WT) strain by whole genome and RNA sequencing. While this effort increased our understanding of the aromatic tolerance, the tolerance mechanisms were not completely elucidated. Results We hypothesize that the composition of lipids plays an important role in phenol tolerance. To test this hypothesis, we applied high-resolution mass spectrometry analysis to lipid samples obtained from the WT and evol40 strains grown in 1 g/L glucose (glucose), 0.75 g/L phenol (low phenol), or 1.5 g/L phenol (high phenol, evol40 only) as a sole carbon source. This analysis identified > 100 lipid species of mycolic acids, phosphatidylethanolamines (PEs), phosphatidylinositols (PIs), and triacylglycerols. In both strains, mycolic acids had fewer double bond numbers in phenol conditions than the glucose condition, and evol40 had significantly shorter mycolic acid chain lengths than the WT strain in phenol conditions. These results indicate that phenol adaptation affected mycolic acid membrane composition. In addition, the percentage of unsaturated phospholipids decreased for both strains in phenol conditions compared to the glucose condition. Moreover, the PI content increased for both strains in the low phenol condition compared to the glucose condition, and the PI content increased further for evol40 in the high phenol condition relative to the low phenol condition. Conclusions This work represents the first comprehensive lipidomic study on the membrane of R. opacus grown using phenol as a sole carbon source. Our results suggest that the alteration of the mycolic acid and phospholipid membrane composition may be a strategy of R. opacus for phenol tolerance. |
| first_indexed | 2024-12-12T11:02:27Z |
| format | Article |
| id | doaj.art-0cfccb70b2bf457a955e77305d430cd9 |
| institution | Directory Open Access Journal |
| issn | 1754-6834 |
| language | English |
| last_indexed | 2024-12-12T11:02:27Z |
| publishDate | 2018-12-01 |
| publisher | BMC |
| record_format | Article |
| series | Biotechnology for Biofuels |
| spelling | doaj.art-0cfccb70b2bf457a955e77305d430cd92022-12-22T00:26:28ZengBMCBiotechnology for Biofuels1754-68342018-12-0111111510.1186/s13068-018-1337-zLipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversionWilliam R. Henson0Fong-Fu Hsu1Gautam Dantas2Tae Seok Moon3Marcus Foston4Department of Energy, Environmental and Chemical Engineering, Washington University in St. LouisMass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid Research, Department of Internal Medicine, Washington University School of MedicineDepartment of Pathology and Immunology, Washington University in St. Louis School of MedicineDepartment of Energy, Environmental and Chemical Engineering, Washington University in St. LouisDepartment of Energy, Environmental and Chemical Engineering, Washington University in St. LouisAbstract Background Lignin is a recalcitrant aromatic polymer that is a potential feedstock for renewable fuel and chemical production. Rhodococcus opacus PD630 is a promising strain for the biological upgrading of lignin due to its ability to tolerate and utilize lignin-derived aromatic compounds. To enhance its aromatic tolerance, we recently applied adaptive evolution using phenol as a sole carbon source and characterized a phenol-adapted R. opacus strain (evol40) and the wild-type (WT) strain by whole genome and RNA sequencing. While this effort increased our understanding of the aromatic tolerance, the tolerance mechanisms were not completely elucidated. Results We hypothesize that the composition of lipids plays an important role in phenol tolerance. To test this hypothesis, we applied high-resolution mass spectrometry analysis to lipid samples obtained from the WT and evol40 strains grown in 1 g/L glucose (glucose), 0.75 g/L phenol (low phenol), or 1.5 g/L phenol (high phenol, evol40 only) as a sole carbon source. This analysis identified > 100 lipid species of mycolic acids, phosphatidylethanolamines (PEs), phosphatidylinositols (PIs), and triacylglycerols. In both strains, mycolic acids had fewer double bond numbers in phenol conditions than the glucose condition, and evol40 had significantly shorter mycolic acid chain lengths than the WT strain in phenol conditions. These results indicate that phenol adaptation affected mycolic acid membrane composition. In addition, the percentage of unsaturated phospholipids decreased for both strains in phenol conditions compared to the glucose condition. Moreover, the PI content increased for both strains in the low phenol condition compared to the glucose condition, and the PI content increased further for evol40 in the high phenol condition relative to the low phenol condition. Conclusions This work represents the first comprehensive lipidomic study on the membrane of R. opacus grown using phenol as a sole carbon source. Our results suggest that the alteration of the mycolic acid and phospholipid membrane composition may be a strategy of R. opacus for phenol tolerance.http://link.springer.com/article/10.1186/s13068-018-1337-zRhodococcus opacusPhenolTriacylglycerolMycolic acidPhospholipidMass spectrometry |
| spellingShingle | William R. Henson Fong-Fu Hsu Gautam Dantas Tae Seok Moon Marcus Foston Lipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversion Biotechnology for Biofuels Rhodococcus opacus Phenol Triacylglycerol Mycolic acid Phospholipid Mass spectrometry |
| title | Lipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversion |
| title_full | Lipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversion |
| title_fullStr | Lipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversion |
| title_full_unstemmed | Lipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversion |
| title_short | Lipid metabolism of phenol-tolerant Rhodococcus opacus strains for lignin bioconversion |
| title_sort | lipid metabolism of phenol tolerant rhodococcus opacus strains for lignin bioconversion |
| topic | Rhodococcus opacus Phenol Triacylglycerol Mycolic acid Phospholipid Mass spectrometry |
| url | http://link.springer.com/article/10.1186/s13068-018-1337-z |
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