Evidence for lignin oxidation by the giant panda fecal microbiome.
The digestion of lignin and lignin-related phenolic compounds from bamboo by giant pandas has puzzled scientists because of the lack of lignin-degrading genes in the genome of the bamboo-feeding animals. We constructed a 16S rRNA gene library from the microorganisms derived from the giant panda fece...
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2012-01-01
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| Series: | PLoS ONE |
| Online Access: | https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23209704/?tool=EBI |
| _version_ | 1818405397217673216 |
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| author | Wei Fang Zemin Fang Peng Zhou Fei Chang Yuzhi Hong Xuecheng Zhang Hui Peng Yazhong Xiao |
| author_facet | Wei Fang Zemin Fang Peng Zhou Fei Chang Yuzhi Hong Xuecheng Zhang Hui Peng Yazhong Xiao |
| author_sort | Wei Fang |
| collection | DOAJ |
| description | The digestion of lignin and lignin-related phenolic compounds from bamboo by giant pandas has puzzled scientists because of the lack of lignin-degrading genes in the genome of the bamboo-feeding animals. We constructed a 16S rRNA gene library from the microorganisms derived from the giant panda feces to identify the possibility for the presence of potential lignin-degrading bacteria. Phylogenetic analysis showed that the phylotypes of the intestinal bacteria were affiliated with the phyla Proteobacteria (53%) and Firmicutes (47%). Two phylotypes were affiliated with the known lignin-degrading bacterium Pseudomonas putida and the mangrove forest bacteria. To test the hypothesis that microbes in the giant panda gut help degrade lignin, a metagenomic library of the intestinal bacteria was constructed and screened for clones that contained genes encoding laccase, a lignin-degrading related enzyme. A multicopper oxidase gene, designated as lac51, was identified from a metagenomic clone. Sequence analysis and copper content determination indicated that Lac51 is a laccase rather than a metallo-oxidase and may work outside its original host cell because it has a TAT-type signal peptide and a transmembrane segment at its N-terminus. Lac51 oxidizes a variety of lignin-related phenolic compounds, including syringaldazine, 2,6-dimethoxyphenol, ferulic acid, veratryl alcohol, guaiacol, and sinapinic acid at conditions that simulate the physiologic environment in giant panda intestines. Furthermore, in the presence of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), syringic acid, or ferulic acid as mediators, the oxidative ability of Lac51 on lignin was promoted. The absorbance of lignin at 445 nm decreased to 36% for ABTS, 51% for syringic acid, and 51% for ferulic acid after incubation for 10 h. Our findings demonstrate that the intestinal bacteria of giant pandas may facilitate the oxidation of lignin moieties, thereby clarifying the digestion of bamboo lignin by the animal. |
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| format | Article |
| id | doaj.art-3b358bbe644e4fe98db7b7dddef08f17 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-14T08:55:24Z |
| publishDate | 2012-01-01 |
| publisher | Public Library of Science (PLoS) |
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| spelling | doaj.art-3b358bbe644e4fe98db7b7dddef08f172022-12-21T23:08:56ZengPublic Library of Science (PLoS)PLoS ONE1932-62032012-01-01711e5031210.1371/journal.pone.0050312Evidence for lignin oxidation by the giant panda fecal microbiome.Wei FangZemin FangPeng ZhouFei ChangYuzhi HongXuecheng ZhangHui PengYazhong XiaoThe digestion of lignin and lignin-related phenolic compounds from bamboo by giant pandas has puzzled scientists because of the lack of lignin-degrading genes in the genome of the bamboo-feeding animals. We constructed a 16S rRNA gene library from the microorganisms derived from the giant panda feces to identify the possibility for the presence of potential lignin-degrading bacteria. Phylogenetic analysis showed that the phylotypes of the intestinal bacteria were affiliated with the phyla Proteobacteria (53%) and Firmicutes (47%). Two phylotypes were affiliated with the known lignin-degrading bacterium Pseudomonas putida and the mangrove forest bacteria. To test the hypothesis that microbes in the giant panda gut help degrade lignin, a metagenomic library of the intestinal bacteria was constructed and screened for clones that contained genes encoding laccase, a lignin-degrading related enzyme. A multicopper oxidase gene, designated as lac51, was identified from a metagenomic clone. Sequence analysis and copper content determination indicated that Lac51 is a laccase rather than a metallo-oxidase and may work outside its original host cell because it has a TAT-type signal peptide and a transmembrane segment at its N-terminus. Lac51 oxidizes a variety of lignin-related phenolic compounds, including syringaldazine, 2,6-dimethoxyphenol, ferulic acid, veratryl alcohol, guaiacol, and sinapinic acid at conditions that simulate the physiologic environment in giant panda intestines. Furthermore, in the presence of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), syringic acid, or ferulic acid as mediators, the oxidative ability of Lac51 on lignin was promoted. The absorbance of lignin at 445 nm decreased to 36% for ABTS, 51% for syringic acid, and 51% for ferulic acid after incubation for 10 h. Our findings demonstrate that the intestinal bacteria of giant pandas may facilitate the oxidation of lignin moieties, thereby clarifying the digestion of bamboo lignin by the animal.https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23209704/?tool=EBI |
| spellingShingle | Wei Fang Zemin Fang Peng Zhou Fei Chang Yuzhi Hong Xuecheng Zhang Hui Peng Yazhong Xiao Evidence for lignin oxidation by the giant panda fecal microbiome. PLoS ONE |
| title | Evidence for lignin oxidation by the giant panda fecal microbiome. |
| title_full | Evidence for lignin oxidation by the giant panda fecal microbiome. |
| title_fullStr | Evidence for lignin oxidation by the giant panda fecal microbiome. |
| title_full_unstemmed | Evidence for lignin oxidation by the giant panda fecal microbiome. |
| title_short | Evidence for lignin oxidation by the giant panda fecal microbiome. |
| title_sort | evidence for lignin oxidation by the giant panda fecal microbiome |
| url | https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23209704/?tool=EBI |
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