# US 10,870,829 B2 · Technology to identify Candida auris > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,870,829 B2 - Document ID: US10870829B2 - Status: Granted - Kind: B2 - Application number: 16/872,436 - Filed: 2020-05-12 - Published: 2020-08-27 - Granted: 2020-12-22 - Earliest claimed: 2018-05-06 - Assignees: Santa Fe BioLabs LLC - Applicants: Santa Fe BioLabs LLC - Inventors: Wolfram Siede - Web page: https://patentgrep.com/patent/US10870829B2 ## CPC - C12N 1/16: Yeasts; Culture media therefor - C12N 2500/32: Amino acids - C12N 2500/34: Sugars - C12N 2500/74: from fungi, e.g. yeasts - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) ## Abstract A system for identifying Candida auris is disclosed. The system has two aspects. The first is a positive selection of C. auris based on C. auris's distinctive resistance to quaternary ammonium compounds (especially at elevated incubation temperatures). The second is a negative selection of C. auris based on C. auris's distinctive sensitive to tert-Butyl-hydroperoxide. C. auris can be identified in a sample through use of a positive-selection culture medium, which fosters C. auris colony growth while suppressing growth of other yeasts. The isolate can be confirmed as C. auris through use of a negative-selection culture medium, which suppresses C. auris colony growth while permitting growth of other yeasts. ## Claims ### Claim 1 A method for detecting Candida auris, the method comprising: (a) placing a first sample in or on a first Candida-auris positive-selection culture medium comprising a sugar, a yeast supplement, and a Quaternary Ammonium Compound, thereby inoculating the first Candida-auris positive-selection culture medium with the first sample; and (b) incubating the inoculated first Candida-auris positive-selection culture medium at a temperature in the range of approximately 36.5° C.-39.0° C. for at least 24 hours. ### Claim 2 (depends on 1) The method of claim 1 wherein the yeast supplement is a nutritionally poor and defined supplement mixture. ### Claim 3 (depends on 2) The method of claim 2 further comprising: (a) collecting a second sample from cultures on the incubated inoculated first Candida auris positive-selection culture medium; (b) placing the second sample in or on a second Candida-auris positive-selection culture medium comprising a sugar, a nutritionally rich and complex supplement mixture supplement, and a Quaternary Ammonium Compound, thereby inoculating the second Candida-auris positive-selection culture medium with the second sample; (c) incubating the inoculated second Candida auris positive-selection culture medium at a temperature in the range of approximately 36.5° C.-39.0° C. for at least 36 hours. ### Claim 4 (depends on 3) The method of claim 3 wherein: (a) the step of incubating the inoculated first Candida auris positive-selection culture medium is at a temperature in the range of 36.5° C.-37.5° C.; and (b) the step of incubating the inoculated second Candida auris positive-selection culture medium is at a temperature in the range of 36.5° C.-37.5° C. ### Claim 5 (depends on 4) The method of claim 4: (a) the first Candida auris positive-selection culture medium comprising: dextrose in the amount of 60 grams per liter of solvent; Yeast Nitrogen Base in the amount of 6.7 grams per liter of solvent; benzalkonium chloride in the amount of 70 milligrams per liter of solvent; and tetradecyltrimethylammonium bromide in the amount of 80 milligrams per liter of solvent; (b) the second Candida auris positive-selection culture medium comprising: dextrose in the amount of 60 grams per liter of solvent; peptone in the amount of 10 grams per liter of solvent; and benzalkonium chloride in the amount of 130 milligrams per liter of solvent; (c) the first Candida auris positive-selection culture medium further comprising: chloramphenicol in the amount of 25 mg per liter of solvent; and (d) the second Candida auris positive-selection culture medium further comprising: chloramphenicol in the amount of 25 mg chloramphenicol per liter of solvent. ### Claim 6 (depends on 1) The method of claim 1 further comprising: (a) collecting a second sample from cultures on the incubated inoculated first Candida auris positive-selection culture medium; (b) placing the second sample in or on a Candida auris nonselective culture medium, thereby inoculating the Candida-auris nonselective culture medium with the second sample; (c) incubating the inoculated Candida auris nonselective culture medium at a temperature in the range of approximately 29.5° C.-30.5° C. for at least 24 hours; (d) collecting a third sample from cultures on the incubated inoculated Candida auris nonselective culture medium; (e) placing the third sample in or on a Candida auris negative-selection culture medium comprising a sugar, a yeast supplement, and tert-Butyl-hydroperoxide, thereby inoculating the Candida-auris negative-selection culture medium with the second sample; (f) incubating the inoculated Candida auris negative-selection culture medium at a temperature in the range of approximately 29.5° C.-30.5° C. for 22-26 hours. ### Claim 7 (depends on 6) The method of claim 6, the Candida auris negative-selection culture medium comprising: (a) dextrose in the amount of 40 grams per liter of solvent; (b) peptone in the amount of 10 grams per liter of solvent; and (c) tert-butyl-hydroperoxide in the amount of 350 microliters of 70% aqueous solution per liter of solvent. ### Claim 8 (depends on 6) The method of claim 6, the Candida auris negative-selection culture medium comprising: (a) dextrose in the amount of 60 grams per liter of solvent; (b) tryptone in the amount of 20 grams per liter of solvent; (c) 25 milligrams of chloramphenicol per liter of solvent; and (d) tert-butyl-hydroperoxide in the amount of 350 microliters of 70% aqueous solution per liter of solvent. ### Claim 9 (depends on 3) The method of claim 3 further comprising: (a) collecting a third sample from cultures on the incubated inoculated second Candida auris positive-selection culture medium; (b) placing the third sample in or on a Candida auris nonselective culture medium, thereby inoculating the Candida-auris nonselective culture medium with the second sample; (c) incubating the inoculated Candida auris nonselective culture medium at a temperature in the range of approximately 29.5° C.-30.5° C. for at least 24 hours; (d) collecting a fourth sample from cultures on the incubated inoculated Candida auris nonselective culture medium; (e) placing the fourth sample in or on a Candida auris negative-selection culture medium comprising a sugar, a yeast supplement, and tert-Butyl-hydroperoxide, thereby inoculating the Candida-auris negative-selection culture medium with the second sample; (f) incubating the inoculated Candida auris negative-selection culture medium at a temperature in the range of approximately 29.5° C.-30.5° C. for 22-26 hours.