Aspergillus luchuensis

Aspergillus luchuensis
Scientific classification Edit this classification
Kingdom: Fungi
Division: Ascomycota
Class: Eurotiomycetes
Order: Eurotiales
Family: Aspergillaceae
Genus: Aspergillus
Species:
A. luchuensis
Binomial name
Aspergillus luchuensis
Inui, 1901[1]
Synonyms[2][3]
Heterotypic synonyms
  • Aspergillus aureus var. acidus Nakaz., Simo & A.Watan., 1936
    • Aspergillus foetidus var. acidus (Nakaz., Simo & A.Watan.) Al-Musallam, 1980
    • Aspergillus acidus (Nakaz., Simo & A.Watan.) Varga et al., 2011
  • Aspergillus awamori Nakaz., 1911
    • var. ferrugineus Nakaz., Simo & A.Watan., 1936
    • var. fumeus Nakaz., Simo & A.Watan., 1936
    • var. fuscus Nakaz., Simo & A.Watan., 1936
    • var. minimus Nakaz., Simo & A.Watan., 1936
    • var. piceus Nakaz., Simo & A.Watan., 1936
  • Aspergillus coreanus var. rubeolus Yu et al., 2004
  • Aspergillus luchuensis var. rubeolus Y.K.Shih
Non-synonyms
  • NRRL 4948NT (→ Aspergillus welwitschiae):
    • Aspergillus niger subsp. awamori (Nakaz.) Al-Musallam
    • Aspergillus niger var. awamori (Nakaz.) Al-Musallam

Aspergillus luchuensis is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses.[4][5][6] The fungus has been used to make awamori, a distilled spirit in Okinawa Island, Japan,[7] and is also used to make shōchū and sake.[8][9] This species was first isolated and described by Tamaki Inui of the University of Tokyo in 1901.[1][10][11] For more than 100 years there has been confusion between this species and Aspergillus awamori and Aspergillus niger with regard to scientific names and classification.[12]

The scientific name for this species is derived from "Ryukyu", the historical name for Okinawa, Japan.[12] It is authorized as a "national fungi" (国菌, kokkin) along with Aspergillus oryzae, Aspergillus sojae and Aspergillus kawachii by the Scientific Conference of Brewing Society Japan because it is used not only in brewing but also in a variety of foods and is useful in the lives of Japanese people.[12][13]

Its genome has been sequenced by two different research groups, first in 2016,[14] and then in 2017.[15][16] The first sequencing of the A. luchuensis genome reported a genome assembly size of 34.7 Mbp and reported the presence of 11,691 genes.

Taxonomic history

In 1901, Inui described a black Aspergillus (black kōji) from awamori-koji, which he called Aspergillus luchuensis; the type strain was deposited as NBRC 4281. In 1911, Nakazawa isolated a morphologically very similar fungus also from awamori-koji, which he called Aspergillus awamori and deposited as JCM 2261(IAM 2112); the only described difference was the phialides.[12]

In April 1920, a strain NBRC 4314 (RIB 2604), originally isolated from awamori in 1901 by Usami, was stored as A. awamori at Hiroshima University and the IFO (Institute for Fermentation, Osaka). This strain would have its genome sequenced in 2016.[12]

Because JCM 2261 was not accessible to most researchers, many researchers used a morphologically similar strain NRRL 4948 as the neotype strain of a A. niger var. awamori (=A. awamori), using it as the baseline in their understanding of "A. amawori". This strain is however more similar to Brazillian Aspergillus niger (actually most similar to Aspergillus welwitschiae),[3] having nothing to do with actual awamori in its origin. The result is that strains labelled as "A. awamori" by similarity to sequences labelled "A. awamori" include not only a real awamori-derived group, but also a lot of A. niger, leading to much confusion (a nomen ambiguum).[12]

The status of black kōji fungi was finally resolved in 2013 by an international collaboration of Yamada from Japan, Hong from South Korea, Samson from the Netherlands, and others. The living cultures and dead remains of archived strains labelled A. amawori were examined by PCR and other molecular methods. They were found to be a DNA match of A. luchuensis and totally different from A. niger. Because the name A. luchuensis predates A. amawori by 10 years, it was chosen as the correct name of this fungus as a matter of nomenclatural priority.[12][17]

A more detailed history of this species (and other black Aspergillus) is given in Hong, Yamada and Samson (2014).[3]

Remaining confusion

Despite the corrections around 2013, NCBI GenBank still retains the neotype designation of NRRL 4948 as Aspergillus awamori, and as a result the name remains a nomen ambiguum. A 2019 genome of NRRL 4948 under this name adds to the problem.[18] The ATCC also continues to sell a "Aspergillus awamori" WB 4948.[19]

As a result of this confusion, care should be exercised in interpreting the name Aspergillus awamori: if the strain IFM 58123 = NRRL 4948 = CBS 557.65 is used as the type, the name refers to Aspergillus welwitschiae and not A. luchuensis.[3]

White mutant

In 1918, Genichiro Kawachi isolated an albino mutant of Aspergillus luchuensis (black kōji) and named it Aspergillus kawachii (white kōji). This mutant is now also called Aspergillus luchuensis mut. kawachii.[8]

Uses

Brewing

In shōchū brewing, Aspergillus oryzae (yellow kōji) was traditionally used, but black and white kōji produced more citric acid and were more effective in preventing microorganism growth, so the use of black kōji was recommended from the 1940s and white kōji from the 1950s. Brewing with each type of kōji brings different flavors to shōchū.[8]

Sake was also traditionally brewed with yellow kōji, but from the 21st century sake brewed with white or black kōji began to appear.[9]

The black kōji variants and white kōji that Kawachi discovered and isolated have been used in makgeolli and soju in Korea since the 1940s.[20][21]

See also

References

  1. 1 2 Inui T (1901). "Ryukyu awamori hakko kin chyosa houkokusyo". J. Chem. Soc. Japan. 4: 1421–1430.
  2. ↑ "Aspergillus awamori Nakaz". Global Biodiversity Information Facility. Retrieved 23 April 2024.
  3. 1 2 3 4 Hong, Seung-Beom; Yamada, Osamu; Samson, Robert A. (January 2014). "Taxonomic re-evaluation of black koji molds". Applied Microbiology and Biotechnology. 98 (2): 555–561. doi:10.1007/s00253-013-5332-9. PMID 24281756.
  4. ↑ Herman J Pel; et al. (February 2007). "Genome sequencing and analysis of the versatile cell factory Aspergillus niger CBS 513.88". Nature Biotechnology. 25 (2): 221–31. doi:10.1038/nbt1282. hdl:1887/67447. PMID 17259976.
  5. ↑ Israel Goldberg; et al. (2006). "Organic acids: old metabolites, new themes". Journal of Chemical Technology & Biotechnology. 81 (10): 1601–1611. Bibcode:2006JCTB...81.1601G. doi:10.1002/jctb.1590.
  6. ↑ Pariza, M. W; Foster, E. M (1983). "Determining the Safety of Enzymes Used in Food Processing". Journal of Food Protection. 46 (5): 453–468. doi:10.4315/0362-028X-46.5.453. PMID 30913657.
  7. ↑ Yamada Osamu, Takara Ryo, Hamada Ryoko, Hayashi Risa, Tsukahara Masatoshi, Mikami Shigeaki (2011). "Molecular biological researches of Kuro-Koji molds, their classification and safety". J. Biosci. Bioeng. 112 (3): 233–237. doi:10.1016/j.jbiosc.2011.05.005. PMID 21641278.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  8. 1 2 3 Taiki Futagami (May 2022). "The white koji fungus Aspergillus luchuensis mut. kawachii. Bioscience, Biotechnology, and Biochemistry, Volume 86, Issue 5". Bioscience, Biotechnology, and Biochemistry. Japan Society for Bioscience, Biotechnology, and Agrochemistry. pp. 574–584. doi:10.1093/bbb/zbac033. PMID 35238900. Archived from the original on 9 April 2023. Retrieved 9 April 2023.
  9. 1 2 日本酒造りにもたらされた「クエン酸」による変革!! - 白麹、黒麹仕込みの日本酒を学ぶ (in Japanese). Sake Street. 22 May 2022. Archived from the original on 30 September 2022. Retrieved 9 April 2023.
  10. ↑ Osamu Yamada, Masayuki Machida, Akira Hosoyama, Masatoshi Goto, Toru Takahashi, Taiki Futagami, Youhei Yamagata, etc. (20 September 2016). "Genome sequence of Aspergillus luchuensis NBRC 4314". DNA Research. Oxford University Press. pp. 507–515. doi:10.1093/dnares/dsw032. PMC 5144674. PMID 27651094. Archived from the original on 5 June 2018. Retrieved 10 April 2023.{{cite web}}: CS1 maint: multiple names: authors list (link)
  11. ↑ Takeo Koizumi (5 April 2018). "黒麹菌の役割 発酵中の雑菌繁殖防ぐ". Okinawa Times. Archived from the original on 4 April 2023. Retrieved 10 April 2023.
  12. 1 2 3 4 5 6 7 Osamu Yamada. 黒麹菌の学名がAspergillus luchuensisになりました (The scientific name for black koji is now Aspergillus luchuensis.) (in Japanese). Japan Science and Technology Agency. Archived from the original on 19 December 2022. Retrieved 9 April 2023.
  13. ↑ "Declaration" (PDF). The Scientific Conference of Brewing Society Japan. 28 November 2013. Archived from the original (PDF) on 1 May 2022. Retrieved 10 April 2023.
  14. ↑ Yamada O; et al. (2016). "Genome sequence of Aspergillus luchuensis NBRC 4314". DNA Res. 23 (6): 507–515. doi:10.1093/dnares/dsw032. PMC 5144674. PMID 27651094.
  15. ↑ de Vries R. P.; et al. (2017). "Comparative genomics reveals high biological diversity and specific adaptations in the industrially and medically important fungal genus Aspergillus". Genome Biology. 18 (1) 28. Bibcode:2017GenBi..18...28D. doi:10.1186/s13059-017-1151-0. PMC 5307856. PMID 28196534.
  16. ↑ "Aspergillus luchuensis CBS 106.47 v1.0".
  17. ↑ Hong, S. B.; Lee, M.; Kim, D. H.; Varga, J.; Frisvad, J. C.; Perrone, G.; Gomi, K.; Yamada, O.; Machida, M.; Houbraken, J.; Samson, R. A. (28 May 2013). "Aspergillus luchuensis, an industrially important black Aspergillus in East Asia". PLOS ONE. 8 (5) e63769. Bibcode:2013PLoSO...863769H. doi:10.1371/journal.pone.0063769. PMC 3665839. PMID 23723998.
  18. ↑ Shimizu, M; Kusuya, Y; Alimu, Y; Bian, C; Takahashi, H; Yaguchi, T (January 2019). "Draft Genome Sequence of Aspergillus awamori IFM 58123(NT)". Microbiology Resource Announcements. 8 (4) e01453-18. doi:10.1128/MRA.01453-18. PMC 6346188. PMID 30701239.
  19. ↑ "Aspergillus awamori Nakazawa - 16877". ATCC.
  20. ↑ "初代 河内源一郎(1883~1948)". Kawauchi-kin honpo. Archived from the original on 7 May 2020. Retrieved 9 April 2023.
  21. ↑ "元祖 源一郎さんの生マッコリ". Kawauchi-kin honpo. Archived from the original on 7 May 2020. Retrieved 9 April 2023.

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