Secretion and maturation of multiheme cytochromes in iron-reducing bacteria

2015 Fiscal Year Final Research Report

• Project/Area Number: 26850052
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Applied microbiology
• Research Institution: University of Miyazaki
• Principal Investigator: Inoue Kengo 宮崎大学, 農学部, 准教授 (70581304)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 鉄還元菌 / Geobacter / 細胞外電子伝達 / Ⅱ型分泌システム / シトクロムc / ヘム修飾

Outline of Final Research Achievements

Geobacter sulfurreducens is a key player in current production by mixed-culture microbial fuel cells. Among known essential genes for optimal current production, omcZ is the only c-type cytochrome. To reveal the molecular mechanisms of OmcZ secretion and maturation process, we have investigated type-II secretion system (T2SS) by which OmcZ is proposed to be secreted. In G. sulfurreducens genome, there are two T2SS gene clusters (T2SS-I and -II, respectively). We generated disruption mutants of these T2SS-related genes and investigated their cytochrome production and capability of current production in microbial fuel cell. According to the cytochrome production profile results, T2SS-I disrupted mutant could not produce maturated OmcZ but T2SS-II disrupted mutant did not show difference from wild-type G. sulfurreducens strain. However, both mutants could produce current in microbial fuel cell as well as wild-type.

Free Research Field

応用微生物学