Regulation of nitrogen fixation in actinobacteria

2017 Fiscal Year Final Research Report

• Project/Area Number: 26450098
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Applied microbiology
• Research Institution: Kagoshima University
• Principal Investigator: KUCHO Ken-ichi 鹿児島大学, 理工学域理学系, 准教授 (70404473)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 順遺伝学 / 突然変異株 / ゲノム解析 / 窒素固定 / 放線菌 / 酸素防御 / 転写制御

Outline of Final Research Achievements

Frankia spp. are nitrogen-fixing actinobacteria and have several unique properties. Frankia develops vesicles, which are spherical multicellular structure devoted to nitrogen fixation. Frankia genomes do not contain regulatory genes for nitrogen-fixation (nif) genes that are typically found in other nitrogen-fixing bacteria.
We isolated 49 Frankia mutants that cannot fix nitrogen. These mutants included those showed aberrant vesicle phenotypes (less number, smaller size, thinner envelope) and reduced nif gene expression. They are considered to carry mutations in genes involved in vesicle differentiation and nif gene regulation. We analyzed genomes of mutants and revertants, and specified a gene that is responsible for the mutant phenotype.

Free Research Field

微生物遺伝学