Aspergillus oryzae

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Aspergillus oryzae

Kingdom:	Fungi
Division:	Ascomycota
Class:	Eurotiomycetes
Order:	Eurotiales
Family:	Trichocomaceae
Genus:	Aspergillus
Species:	A. oryzae

Binomial name

Aspergillus oryzae
(Ahlburg) Cohn

Aspergillus oryzae (Chinese: 麴菌, 麴霉菌, 曲霉菌, pinyin: qū meí jùn; Japanese: 麹, 麹菌 or kōji-kin, Korean: guk, 麹) is a filamentous fungus (a mold) used in Chinese and Japanese cuisine which ferments soybeans to produce soy sauce and miso. The fungus is also used by both cultures to saccharify rice, potatoes and grains for fermentation in the making of alcoholic beverages as huangjiu, sake, awamori and shōchū. Also, the fungus is used for the production of rice vinegars as the Japanese rice vinegar (awasezu). The protease enzymes produced by this species are marketed by the company Novozymes under the name Flavourzyme. The importance of A. oryzae has led to its recognition as Japan's national micro-organism ("kokkin"), just as the sakura cherry blossom as Japan's national flower.^[1]^[2]

"Red kōji-kin" is a separate species, Monascus purpureus.

1 Properties desirable in sake brewing
2 Genome
3 References
4 External links

[edit] Properties desirable in sake brewing

The following properties of A. oryzae strains are important in rice saccharification for sake brewing:^[2]

Growth – rapid mycelial growth on and into the rice kernels
Enzymes – strong secretion of amylases (α-Amylase and glucoamylase); some carboxypeptidase; low tyrosinase
Aesthetics – pleasant fragrance; accumulation of flavoring compounds
Color – low production of deferriferrichrome (a siderophore), flavins, and other colored substances

[edit] Genome

Initially kept secret, the A. oryzae genome was released by a consortium of Japanese biotechnology companies ^[3] in late 2005^[4]. The eight chromosomes together comprise 37 million base pairs and twelve thousand predicted genes. The genome of A. oryzae is thus one-third larger than that of two related Aspergilli, the genetics model organism Aspergillus nidulans and the dangerous human pathogen Aspergillus fumigatus^[5]. Many of the extra genes present in A. oryzae are predicted to be involved in secondary metabolism. The sequenced strain is called RIB40 or ATCC 42149, and is a wildtype strain that is also used industrially.

[edit] References

^ Fungal Research Trust (2005-12). Retrieved on 2008-01-03.
^ ^a ^b Kitamoto, Katsuhiko (2002). "Molecular Biology of the Koji Molds". Advances in Applied Microbiology 51: 129–153. doi:10.1016/S0065-2164(02)51004-2. PMID 12236056 doi:10.1016/S0065-2164(02)51004-2 .
^ Goffeau, André (December 2005). "Multiple moulds". Nature 438 (7071): 1092–1093. doi:10.1038/4381092b. PMID 16371993.
^ Machida, Masayuki et al. (December 2005). "Genome sequencing and analysis of Aspergillus oryzae". Nature 438: 1157–1161. doi:10.1038/nature04300. PMID 16372010.
^ Galagan, James E. et al. (December 2005). "Sequencing of Aspergillus nidulans and comparative analysis with A. fumigatus and A. oryzae". Nature 438: 1105–1115. doi:10.1038/nature04341. PMID 16372000.