The mechanism of hyperproduction of citric acid by white koji mold, Aspergillus kawachii and application of production of organic acid

2014 Fiscal Year Final Research Report

• Project/Area Number: 24580116
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Applied microbiology
• Research Institution: Kyushu University
• Principal Investigator: GOTO Masatoshi 九州大学, (連合)農学研究科(研究院), 准教授 (90274521)
• Co-Investigator(Kenkyū-buntansha): FUTAGAMI Taiki 鹿児島大学, 農学部, 准教授 (60512027)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: Aspergillus / 麹菌 / 有機酸発酵 / ゲノム解析 / マイクロアレイ解析

Outline of Final Research Achievements

We attempted to elucidate the mechanism for hyperproduction of citric acid by Aspergillus kawachii. A. kawachii ligD-disruptant which exhibits the ability of homologous recombination with high efficiency was constructed and auxotrophic strains were constructed. Approximately 1,100 genes that show differential expression after shifting cultivation at high temperature to cultivation at low temperature were identified. Gene ontology analysis revealed that A. kawachii is stressed from cultivation at high temperature that enhances the amylase activity and responds to protect against heat damage. Cultivation of A. kawachii at low temperature enhances production of citric acid. Under this condition EMP pathway to form pyruvate was reinforced by the repression of metabolic pathways for synthesis of glycerol and trehalose, and pentose phosphate in A. kawachii. Thirty six genes were selected to be important for high production of citric acid and 35 genes were disrupted in A. kawachii.

Free Research Field

応用微生物学