Genomic insights into an evolution of widely-distributed lactic acid bacterium Latilactobacillus sakei and its future use

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05346
• 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: Ishikawa Prefectural University
• Principal Investigator: KOYANAGI Takashi 石川県立大学, 生物資源環境学部, 准教授 (20535041)
• Co-Investigator(Kenkyū-buntansha): 高木 宏樹 石川県立大学, 生物資源環境学部, 准教授 (80616467)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 乳酸菌 / ゲノム解析 / Latilactobacillus sakei / 次世代シーケンサー / 種内系統解析

Outline of Final Research Achievements

Latilactobacillus sakei is a widely distributed lactic acid bacteria isolated from a variety of foods and related ingredients, such as fermented meat, fermented pickles, Japanese rice wine starter (shubo), and fermented fish with rice koji (Izushi-type narezushi). The richness of such isolation sources suggests the intraspecific diversity in L. sakei species, but detailed information on the relationships among strains has not been fully elucidated until now. In this study, we constructed single nucleotide polymorphism (SNP)-concatenated sequences from the whole-genome nucleotide sequence data of 32 L. sakei strains and found that the strains were separated according to the nutrient types in the source of isolation, such as whether they contained animal nutrition. The SNP-based method on L. sakei established in this study may lead to efficient selection of optimal fermentation starters, and may be used for industrial applications in the future.

Free Research Field

食品微生物学、応用微生物学

Academic Significance and Societal Importance of the Research Achievements

本課題では、SNP結合塩基配列に基づく種内系統解析を特定の乳酸菌種に適用することにより、これまでの既存手法では見いだされなかった詳細な菌株の類縁関係に関する系統分類に成功した。本手法はL. sakeiのみならずその他の乳酸菌種にも適用可能であり、過去に明らかでなかった種内での系統整理に役立つ可能性がある。さらに、各菌株の表現形質などと関連付けた解析を今後進めることにより、ゲノム情報をもとにした最適発酵スターター株の選抜に利用できるなどの可能性が十分ある。本課題における成果は、乳酸菌の種内系統分類に新手法を導入した学術的意義のみならず、上記のような将来的産業利用につながる社会的意義も有している。