pro·​te·​ase | \ ˈprō-tē-ˌās How to pronounce protease (audio) , -ˌāz \

Definition of protease

: any of numerous enzymes that hydrolyze proteins and are classified according to the most prominent functional group (such as serine or cysteine) at the active site

called also proteinase

Examples of protease in a Sentence

Recent Examples on the Web The pharmaceutical industry developed a class of antiviral drugs to treat AIDS/H.I.V., called protease inhibitors, some of which were approved within 40 days. New York Times, "Biden Picks Former F.D.A. Chief to Lead Federal Vaccine Efforts," 15 Jan. 2021 The protease inhibitors and other compounds look promising in cell and animal studies. Science News Staff, Science | AAAS, "The science stories likely to make headlines in 2021," 31 Dec. 2020 One, sponsored by the University of Oxford, tested multiple treatments, including the antimalarial hydroxychloroquine, HIV protease inhibitors lopinavir and ritonavir, and steroid dexamethasone. Annette Bakker, Fortune, "COVID-19 could change clinical trials for the better," 12 Dec. 2020 Other drugs currently in clinical trials, such as the HIV drug lopinavir, are known as protease inhibitors and prevent the virus from breaking its proteins down into particles that spread through the body. Sara Reardon, Scientific American, "For COVID Drugs, Months of Frantic Development Lead to Few Outright Successes," 13 Nov. 2020 These drugs inhibited the viral protease enzyme responsible for longer precursor proteins in the short active components of the virus. William A. Haseltine, Scientific American, "Lessons from AIDS for the COVID-19 Pandemic," 1 Oct. 2020 Lopinavir also can inhibit enzymes that perform similar functions as the HIV protease in the SARS and MERS coronaviruses. William Petri, The Conversation, "Which drugs and therapies are proven to work, and which ones don’t, for COVID-19?," 1 July 2020 A couple of months ago a group of scientists announced their discovery of a new drug candidate that inhibits that protease. William A. Haseltine, Scientific American, "Lessons for COVID-19 from the Early Days of AIDS," 6 July 2020 The main protease enzyme breaks that long string of Legos into usable pieces, said Dr. Cisneros. Dallas News, "UT Southwestern scientists investigate pneumonia drug as possible COVID-19 treatment," 1 July 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'protease.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of protease

1903, in the meaning defined above

History and Etymology for protease

International Scientific Vocabulary

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Time Traveler for protease

Time Traveler

The first known use of protease was in 1903

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Statistics for protease

Last Updated

23 Jan 2021

Cite this Entry

“Protease.” Dictionary, Merriam-Webster, Accessed 7 Mar. 2021.

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More Definitions for protease


pro·​te·​ase | \ ˈprōt-ē-ˌās, -ˌāz How to pronounce protease (audio) \

Medical Definition of protease

: any of numerous enzymes that hydrolyze proteins and are classified according to the most prominent functional group (as serine or cysteine) at the active site

called also proteinase

— compare peptidase

More from Merriam-Webster on protease Encyclopedia article about protease

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