Candida blankii

Candida blankii
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Ascomycota
Class:	Saccharomycetes
Order:	Saccharomycetales
Family:	Saccharomycetaceae
Genus:	Candida
Species:	C. blankii
Binomial name
Candida blankii H.R. Buckley & Uden, 1968
Synonyms[1][2]
Candida hydrocarbofumarica K. Yamada, T. Furuk. & Nakahara, 1974

Candida blankii is a species of budding yeast (Saccharomycotina) in the family Saccharomycetaceae.^[3][4] The yeast may be a dangerous pathogen and resistant to treatment in human hosts. Research on the fungi has therapeutic, medical and industrial implications.

Taxonomy

Candida blankii was discovered in the 1960s, after the analysis of the organs of infected mink in Canada by F. Blank. These mink were infected with the unknown yeast, and all died from mycosis.^[5][6][7] It was described in 1968 by H. R. Buckley and N. van Uden, who named it in honour of Blank.^[5][8] The description was published in the journal Mycopathologia et Mycologia Applicata, along with descriptions of four other new species.^[6]

Identification

On Sabouraud dextrose agar, C. blankii isolates present as typical yeast, i.e., cream-colored colonies, which then tend toward pink and later dark blue. Blood sample DNA sequencing of the 26S ribosomal subunit can definitively identify C. blankii.^[3]

Ecology

In nature, Candida blankii forms symbiotic relationships with other organisms. An Indian study of seven bee species and 9 plant species found 45 yeast species from 16 genera colonise the nectaries of flowers and honey stomachs of bees. Most were members of the genus Candida; the most common species in honey bee stomachs was Dekkera intermedia, while the most common species colonising flower nectaries was C. blankii. Although the mechanics are not fully understood, it was found that Azadirachta indica flowers more if C. blankii are present.^[7]

Human pathology

Main article: Yeast § Pathogenic yeasts

A few human infections of Candida blankii have been found. Their existence suggests that the condition may have been under-reported.^[3] In 2015, the yeast was found in the airways of a patient with cystic fibrosis; this was the first recorded case of C. blankii infection in humans.^[5] A second case was reported in 2018. The fungus proved resistant to treatment with antifungals. The yeast was characterized as "an opportunist pathogen for lung transplant and/or CF patients".^[3] Because of its resistance, it was said to warrant further study.^[3][9] Different strains, it was suggested, should also be studied "to increase knowledge of genetic diversity and antifungal susceptibility profile".^[3]

Fungal blood-stream infections (fungaemia) have been newly associated with C blankii.^[9] Polyene antifungals have been identified as a possible treatment.^[3]

The species has been detected in meat intended for human consumption, including Iberian ham.^[10]

Biotechnology

Main articles: Yeast § Industrial ethanol production, Bioethanol, and Zymology

Like many yeasts, Candida blankii has been the subject of various biotechnological studies,^[11][12] including for use as a BOD biosensor.^[13][14] The metabolic process of C. blankii is aerobic. Consequently, it oxidizes many forms of alcohol, amino acid, carbohydrates, and other organic compounds. As a BOD biosensor, practical applications may be limited due to short term effectiveness.^{[note 1]}

A diploid isolate of C. blankii had an observed "potential for use in single cell protein production from hemicellulose hydrolysates", which is related to Cellulosic ethanol (i.e., ethanol production).^[15]

This yeast is one of several studied extensively for use in xylose fermentation.^[16][17]

Candida blankii has been tested as an aid for the degradation of hemicellulose hydrolysates.^[18] C. blankii "cultivated on a mixture of n-paraffins (6% vol/vol) has been shown to produce fumaric acid", which could be important in ethanol production, once the process is worked out.^[19][20]

Notes

1. It has been tested as a water quality indicator in comparison to a pair of other Candida species. Its growth phase (hours 14 through 38) and lag phase (hours 0 through 14) were exceptional. However, maximum oxidative activity is typically about 18 hours throughout its lifespan, and biosensor activity declines by half in a little over a week.^[14]

References

1. "Synonymy: Candida blankii". Species Fungorum. Retrieved 24 March 2019.
2. "Candida blankii". MycoBank. Retrieved 24 March 2019.
3. João Nobrega de Almeida, Jr; Silvia V. Campos; Danilo Y. Thomaz; Luciana Thomaz; Renato K. G. de Almeida; Gilda M. B. Del Negro; Viviane F. Gimenes; Rafaella C. Grenfell; Adriana L. Motta; Flávia Rossi; Gil Benard (2018). "Candida blankii: an emergent opportunistic yeast with reduced susceptibility to antifungals". Emerging Microbes & Infections. 7 (1): 24. doi:10.1038/s41426-017-0015-8. PMC 5841406. PMID 29515103.
4. • Kreger-van Rij, N. J. W., ed. (1984) [1967]. The Yeasts: A Taxonomic Study (3rd ed.). Elsevier Science Publishers B.V. p. 633. ISBN 0-444-80421-8. Retrieved 2023-06-10.
   • "Yeast Species Database". Retrieved 2010-12-24.
5. Zaragoza S, Galanternik L, Vazquez M, Teper A, Córdoba S, Finquelievich J (2015). "Candida blankii: New agent in cystic fibrosis airways?". Journal of Cystic Fibrosis. 14: S140. doi:10.1016/S1569-1993(15)30492-6.
6. Buckley, H. R.; van Uden, N. (1968). "Five new Candida species". Mycopathologia et Mycologia Applicata. 36 (3–4). Kluwer Academic Publishers: 257–266. doi:10.1007/BF02050372. ISSN 0027-5530. PMID 5750670. S2CID 42208175. Online.
7. Sandhu DK, Waraich MK (1985). "Yeasts associated with pollinating bees and flower nectar". Microbial Ecology. 11 (1): 51–58. doi:10.1007/BF02015108. JSTOR 4250820. PMID 24221239. S2CID 1776642.
8. Page image list, Index of Fungi 3: 506 (1961–1970) Libri fungorum
9. Al-Haqqan A, Al-Sweih N, Ahmad S, Khan S, Joseph L, Varghese S, Khan Z (2018). "New resistant microbes in humans: Azole-resistant Candida blankii as a newly recognized cause of bloodstream infection". New Microbes and New Infections. 26: 25–29. doi:10.1016/j.nmni.2018.06.008. PMC 6141729. PMID 30245830.
10. Toldrá, Fidel (October 2014). Toldrá, Fidel; Hui, Y. H.; Astiasaran, Iciar; Sebranek, Joseph; Talon, Regine (eds.). Handbook of Fermented Meat and Poultry (2nd ed.). Chichester, West Sussex, UK: Wiley-Blackwell. p. 140. ISBN 978-1-118-52267-7.
11. Hristozovaa T, Gotchevab V, Tzvetkovaa B, Paskalevaa D, Angelov A (September 2008). "Enzyme and Microbial Technology: Effect of furfural on nitrogen assimilating enzymes of lactose utilizing yeasts Candida blankii 35 and Candida pseudotropicalis". Enzyme and Microbial Technology. 43 (3, 5): 284–288. doi:10.1016/j.enzmictec.2008.03.014.
12. Ying Zhao; Jasper Fuk-Woo Chan; Chi-Ching Tsang; He Wang; Dawen Guo; Yuhong Pan; Yuling Xiao; Na Yue; Jonathan Hon-Kwan Chen; Susanna Kar-Pui Lau; Yingchun Xu; Patrick Chiu-Yat Woo (2015). D. W. Warnock (ed.). "Clinical Characteristics, Laboratory Identification, and In Vitro Antifungal Susceptibility of Yarrowia (Candida) lipolytica Isolates Causing Fungemia: a Multicenter, Prospective Surveillance Study". Journal of Clinical Microbiology. 53 (11). American Society for Microbiology: 3639–3645. doi:10.1128/JCM.01985-15. PMC 4609733. PMID 26311865.
13. Meyer, P. S.; Du Preez, J. C.; Kilian, S. G. (1992). "Chemostat cultivation of Candida blankii on sugar cane bagasse hemicellulose hydrolysate". Biotechnology and Bioengineering. 40 (3): 353–358. doi:10.1002/bit.260400304. PMID 18601125. S2CID 32148823.
14. Arlyapova, Viacheslav; Kamanina, Stanislav; Ponamorevaa, Olga; Reshetilov, Anatoly (2012). "Biosensor analyzer for BOD index express control on the basis of the yeast microorganisms Candida maltosa, Candida blankii, and Debaryomyces hansenii". Enzyme and Microbial Technology. 50 (4–5): 215–20. doi:10.1016/j.enzmictec.2012.01.002. PMID 22418260.
15. Meyer PS, du Preez JC, Wingfield BD, Kilian SG (June 1993). "Evaluation of Candida blankii hybrids for biomass production". Journal of Biotechnology. 29 (3): 267–275. doi:10.1016/0168-1656(93)90058-U.
16. Singh, Om V.; Harvey, Steven P., eds. (November 25, 2009). Sustainable Biotechnology: Sources of Renewable Energy. Dordrecht London: Springer. pp. 71, 77. ISBN 9789048132959.
17. Walker, Graeme M. (April 1, 1998). Yeast Physiology and Biotechnology (1st ed.). Chichester New York: John Wiley & Son. p. 230. ISBN 0471964476.
18. Meyer PS, Du Preez JC, Kilian SG (1992). "Effect of temperature and pH on Candida blankii in chemostat culture". World Journal of Microbiology & Biotechnology. 8 (4): 434–438. doi:10.1007/BF01198761. ISSN 0959-3993. PMID 24425519. S2CID 689861.
19. Hui, Y. H. (1995). Khachatourians, George G. (ed.). Food Biotechnology: Microorganisms. John Wiley & Sons. p. 341. ISBN 0471185701.
20. Tsekova K, Kaimaktchiev A, Krumov A (1999). "Production of Fumaric Acid from n-Alcanes by Candida Blankii NA-83". Biotechnology & Biotechnological Equipment. 13 (2): 24–26. doi:10.1080/13102818.1999.10819032.

External links

• Candida blankii on MycoBank
• Candida blankii on Index Fungorum
• Candida blankii MicrobeWiki, Boston University