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Prototheca

noun

Pro·​to·​the·​ca ˌprōt-ə-ˈthē-kə How to pronounce Prototheca (audio)
: a genus of unicellular algae that resemble algae of the genus Chlorella but lack chlorophyll and that include two (P. zopfii and P. wickerhamii) that cause mastitis in cows and sometimes localized infection (as of the skin) in humans

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“Prototheca.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/Prototheca. Accessed 29 Nov. 2025.

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