Analysis of the Lysogenization Mechanism of Bacillus Phage SPbeta through Homologous Recombination

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K15440
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 38020:Applied microbiology-related
• Research Institution: Rikkyo University
• Principal Investigator: Suzuki Shota 立教大学, 理学部, 助教 (00792714)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 溶原性ファージ / 相同組換え / 溶原化 / 部位特異的組換え / 枯草菌

Outline of Final Research Achievements

Upon infection, Bacillus phage SPβ is incorporated into the host genome through its site-specific recombination mechanism (SSR), which is encoded within its own genome. Whereas, it has been demonstrated that in the absence of the integration site in the host genome, SPβ integrates through homologous regions present in the SPβ genome. This study reveals the characteristics of homologous recombination utilized as a phage integration mechanism by investigating the preference of specific homologous regions for SPβ-mediated recombination, exploring factors involved in homologous recombination within the SPβ genome, and analyzing the function of homologous regions in SPβ with respect to integration. Additionally, the potential involvement of highly frequent homologous recombination regions in the abortive infection mechanism mediated by the integrative conjugative element ICEBs1 is suggested.

Free Research Field

分子生物学

Academic Significance and Societal Importance of the Research Achievements

近年バクテリオファージは、宿主特異的感染や短時間で膨大な数の増殖が可能である特徴を利用してファージセラピーやゲノム合成など医学や合成生物学の分野に応用され注目されている。SPβファージの溶原化機構における相同組換えの利用およびその特性を示し、可能性遺伝因子（ICE）による不稔感染に相同領域が関与する可能性を見出した本研究成果は、ファージの研究分野および外来因子間における宿主感染戦略の理解に新しい知見として貢献できるものであり学術的に意義があると考える。またpSSβベクターを利用した有益な形質の一時的な導入と任意の時期に形質を戻せる可逆的形質転換系は枯草菌の育種や工業的な応用が期待される。