Candida blankii

Candida blankii is a species of budding yeast (Saccharomycotina) in the family Saccharomycetaceae.

• The yeast may be a dangerous pathogen and resistant to treatment in human hosts. Research on this fungus 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. The description was published in the journal Mycopathologia et Mycologia Applicata, along with descriptions of four other new species.

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.

Ecology

In nature, C.a 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 honeybee stomachs was Dekkera intermedia, while the most common species colonising flower nectaries was C. blankii. Although the mechanics are not fully understood, Azadirachta indica was found to flower more if C. blankii is present.

Human pathology

Main article: Yeast#Pathogenic yeasts

A few human infections of C. blankii have been found. Their existence suggests that the condition may have been under-reported. 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. 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". Because of its resistance, it was said to warrant further study. Different strains, it was suggested, should also be studied "to increase knowledge of genetic diversity and antifungal susceptibility profile".

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

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

Biotechnology

Main article: Yeast#Industrial ethanol production, Bioethanol, Zymology

Like many yeasts, C. blankii has been the subject of various biotechnological studies, including for use as a BOD biosensor. 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.

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).

This yeast is one of several studied extensively for use in xylose fermentation.

C. blankii has been tested as an aid for the degradation of hemicellulose hydrolysates. 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.

Notes

References

References

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2. "''Candida blankii''". [[MycoBank]].
3. (2018). "''Candida blankii'': an emergent opportunistic yeast with reduced susceptibility to antifungals". [[Emerging Microbes & Infections]].
4. It was [[scientific description
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6. (1985). "Yeasts associated with pollinating bees and flower nectar". Microbial Ecology.
7. (2015). "''Candida blankii'': New agent in cystic fibrosis airways?". Journal of Cystic Fibrosis.
8. (2018). "New resistant microbes in humans: Azole-resistant ''Candida blankii'' as a newly recognized cause of bloodstream infection". [[New Microbes and New Infections]].
9. (October 2014). "Handbook of Fermented Meat and Poultry". [[Wiley-Blackwell]].
10. (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]].
11. (2015). "Clinical Characteristics, Laboratory Identification, and In Vitro Antifungal Susceptibility of Yarrowia (Candida) lipolytica Isolates Causing Fungemia: a Multicenter, Prospective Surveillance Study". [[American Society for Microbiology]].
12. (1992). "Chemostat cultivation of ''Candida blankii'' on sugar cane bagasse hemicellulose hydrolysate". [[Biotechnology and Bioengineering]].
13. (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]].
14. (June 1993). "Evaluation of Candida blankii hybrids for biomass production". [[Journal of Biotechnology]].
15. (November 25, 2009). "Sustainable Biotechnology: Sources of Renewable Energy". Springer.
16. (April 1, 1998). "Yeast Physiology and Biotechnology". [[John Wiley & Son]].
17. (1992). "Effect of temperature and pH on Candida blankii in chemostat culture". [[World Journal of Microbiology & Biotechnology]].
18. Hui, Y. H.. (1995). "Food Biotechnology: Microorganisms". John Wiley & Sons.
19. (1999). "Production of Fumaric Acid from n-Alcanes by Candida Blankii NA-83". [[Biotechnology & Biotechnological Equipment]].