RRC ID 74604
Author Kirimura K, Kobayashi K, Yoshioka I.
Title Decrease of citric acid produced by Aspergillus niger through disruption of the gene encoding a putative mitochondrial citrate-oxoglutarate shuttle protein.
Journal Biosci Biotechnol Biochem
Abstract The transporter that exports citric acid (CA) generated in mitochondria to the cytosol is an important component of the CA production machinery of Aspergillus niger. In this report, we cloned and identified the gene cocA, encoding a 33.7-kDa putative mitochondrial citrate-oxoglutarate shuttle protein of the CA hyper-producer A. niger WU-2223L. The amount of CA produced by a representative cocA disruptant (35 g/L) was significantly lower than that produced by strain WU-2223L (63 g/L) after culture for 12 days under CA production conditions, and the phenotype of the cocA disruptant differed in part from that of strain WU-2223L. A cocA disruptant complemented with cocA exhibited the same phenotypes as those of strain WU-2223L. This report is the first to show that cocA and its protein product clearly contribute to substantial CA production by A. niger, and provides a significant insight into microbial organic acid production by fermentation. Abbreviations: CA: citric acid; CD medium: Czapek-Dox medium; CS: citrate synthase; CTP: citrate transport protein; HR: homologous recombination; MCF: mitochondrial carrier family; RT-PCR: reverse-transcription PCR; TCA: tricarboxylic acid.
Volume 83(8)
Pages 1538-1546
Published 2019-8-1
DOI 10.1080/09168451.2019.1574205
PMID 30720390
MeSH Amino Acid Sequence Aspergillus niger / genetics Aspergillus niger / metabolism* Carrier Proteins / chemistry Carrier Proteins / genetics* Carrier Proteins / metabolism Citric Acid / metabolism* Cloning, Molecular Fermentation Genes, Fungal* Ketoglutaric Acids / metabolism* Mitochondrial Proteins / genetics* Protein Transport Transcription, Genetic
IF 1.516
Resource
Pathogenic eukaryotic microorganisms Aspergillus tubingensis IFM 65578 (= WU-2223L)