Transcriptional activation mechanism by LysR-type transcriptional regulators

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05361
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38020:Applied microbiology-related
• Research Institution: Shizuoka University
• Principal Investigator: Ogawa Naoto 静岡大学, 農学部, 教授 (60354031)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 転写調節 / 細菌 / LysRタイプ転写調節因子 / 芳香族化合物分解 / Burkholderia / Cupriavidus

Outline of Final Research Achievements

The mechanism of transcriptional activation of 3-hydroxybenzoate (3-HB) degradative genes from Burkholderia multivirans ATCC17616 and Cupriavidus necator NH9 was analyzed. The results showed that the transcription of 3-HB degradative genes of both strains was activated by LysR-type regulator, MhbR, of respective strain with 3-HB and gentisic acid as inducers. Five amino acids involved in inducer recognition by MhbR(ATCC17616) were clarified. MhbR(ATCC17616) was further shown to activate transcription of 3-HB degradative genes from C necator NH9. The comparative analysis using the nucleotide sequences of the promoter regions of 3-HB genes of the two strains revealed that MhbR(ATCC17616) recognizes nucleotide sequence of the promoter regions which are distantly related with those previously known as sequences recognized by the LysR-type regulators. This result indicated that the nucleotide sequences recognized by LysR-type regulators are more diverse than previously known.

Free Research Field

微生物学

Academic Significance and Societal Importance of the Research Achievements

LysRタイプ転写調節因子は、細菌では最大の転写調節因子のグループを構成しており、アミノ酸生合成、芳香族化合物分解、病原性因子産生、ストレス応答、窒素固定、二酸化炭素固定など、多くの重要な遺伝子群の発現調節を行っている。一方、近年の様々な細菌のゲノム解読により、１つの細菌は、数十種から、菌株によっては200種近くの、LTTRの遺伝子を持つことが判明している。本研究は、1つの細菌で100前後以上の種類があるLTTRがどのように被制御プロモーターを識別して、さらに特定の誘導物質を認識して、転写活性化を行うのか、という根源的な問いに対して、大きな知見を提供するものであり、学術的意義は高いと考える。