Elucidation of genes that respond to awakening signals in previously uncultured microorganisms

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K05804
• 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: Yasuda Women's University
• Principal Investigator: MURAKAMI Chiho 安田女子大学, 薬学部, 助教 (50649077)
• Co-Investigator(Kenkyū-buntansha): 青井 議輝 広島大学, 統合生命科学研究科(先), 准教授 (40386636)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 難培養性微生物 / 亜硝酸酸化細菌 / Nitrospira / 休眠と覚醒 / RNA-seq / 覚醒シグナル

Outline of Final Research Achievements

The expression levels of all genes were comprehensively investigated by extracting RNA from the previously uncultured Nitrospira strain ND1 and performing next-generation sequencing. As a result, it revealed that ND1 has a third state, awakening, between the dormant and growing states.
Furthermore, it was found that dormant/awakening phenomena are also caused in the Nitrospira strain NJ1 (a different strain known to exist in the vicinity of ND1 in the natural environment). The metabolites of ND1 and NJ1 also induced awakening from each other's dormant state. These results suggested that these strains regulate each other's growth in the natural environment.

Free Research Field

応用微生物

Academic Significance and Societal Importance of the Research Achievements

環境中の多くの微生物が人工培養できない(難培養性)理由についてはほとんど明らかになっていない。本研究結果は, 申請者らが世界で初めて純菌株の獲得に成功した難培養性亜硝酸化細菌（Nitrospira）を用いることで, 環境中の微生物の増殖をコントロールする新しい原理の発見につながる。すなわち、休眠状態にある環境微生物を覚醒させて増殖させるには、代謝物に含まれる覚醒シグナルが必要であることが分かった。