A TonB-dependent receptor constitutes outer membrane transport system for a lignin-derived aromatic compound

生物統合工学専攻 D3 藤田 雅也（政井・上村グループ）

　バクテリアの細胞外膜に普遍的に存在するTonB-dependent receptorが芳香族化合物の輸送と代謝に関与することを初めて明らかにしました。さらに、外膜トランスポーター遺伝子の高発現が、有用物質の生産速度の向上に寄与することを初めて示しました。

発表雑誌

雑誌名：Communications Biology
タイトル：A TonB-dependent receptor constitutes outer membrane transport system for a lignin-derived aromatic compound
著者：Fujita M, Mori K, Hara H, Hishiyama S, Kamimura N, Masai E.
論文URL　https://www.ncbi.nlm.nih.gov/pubmed/31799434

英語要旨
TonB-dependent receptors (TBDRs) mediate substrate-specific transport across the outer membrane, utilizing energy derived from the proton motive force transmitted from the TonB-ExbB-ExbD complex located in the inner membrane (TonB system). Although a number of TonB systems involved in the uptake of siderophores, vitamin B12 and saccharides have been identified, their involvement in the uptake and catabolism of aromatic compounds was previously unknown. Here, we show that the outer membrane transport of a biphenyl compound derived from lignin is mediated by the TonB system in a Gram-negative bacterium capable of degrading lignin-derived aromatic compounds, Sphingobium sp. strain SYK-6. Furthermore, we found that overexpression of the corresponding TBDR gene enhanced the uptake of this biphenyl compound, contributing to the improved rate of platform chemical production. Our results will provide an important basis for establishing engineered strains optimized for use in lignin valorisation.

関連リンク：微生物代謝工学研究室（政井・上村研）