\ ˈhēm How to pronounce heme (audio) \

Definition of heme

: the deep red iron-containing prosthetic group C34H32N4O4Fe of hemoglobin and myoglobin

Examples of heme in a Sentence

Recent Examples on the Web

Neutrophils are full of myloperoxidase (MPO), an enzyme that contains green-colored heme, or iron. Carolyn L. Todd, SELF, "Here’s What It Means If You Have Yellow Mucus," 15 Mar. 2019 Hamdan recommends her own Shiffa Rejuvenating Eye Remedy which is designed to break down excess heme in the skin and help it be reabsorbed over time. Lauren Hubbard, Town & Country, "How to Get Rid of Dark Circles," 4 Feb. 2019 The animal-rights group noted: Impossible Foods’ big claim to fame is that there’s heme in its burgers. Beth Mole, Ars Technica, "PETA roasts Impossible Burger for rat tests, suggests patties cause cancer," 11 Aug. 2018 Impossible Foods’ Impossible Burger falls into this category because its key ingredient is a protein called heme that is produced by genetically engineered yeast. Joi Ito, WIRED, "Fake Meat, Served Six Ways," 2 July 2018 In a fourth, shimmering crimson under the ceiling lights, was the secret sauce: heme (or haem), a component of many proteins, including hemoglobin — the pigment that gives blood its color. Time, "Meet the Founder of Impossible Foods, Whose Meat-Free Burgers Could Transform the Way We Eat," 23 Apr. 2018 This regulator essentially controls whether specific genes are turned on or off depending on the presence of heme within the cell. Beth Mole, Ars Technica, "This capsule of glowing E. coli will probe your gut for signs of trouble," 25 May 2018 These biosensors have been modified to recognize a particular molecule of interest, such as the blood component heme. Karen Kaplan, latimes.com, "This futuristic pill senses signs of disease inside the body, then sends a wireless alert to a phone," 25 May 2018 As a proof of concept, the researchers showed the system could detect the molecule heme in the GI tracts of pigs in a model of GI bleeding. Andrew Joseph, STAT, "Swallow this: A sensor could monitor gut health via engineered bacteria — and beam results to a smartphone," 24 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'heme.' 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 heme

1925, in the meaning defined above

History and Etymology for heme

International Scientific Vocabulary, from hematin

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Time Traveler for heme

The first known use of heme was in 1925

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More Definitions for heme


variants: or chiefly British haem \ ˈhēm How to pronounce haem (audio) \

Medical Definition of heme

: the deep red iron-containing prosthetic group C34H32N4O4Fe of hemoglobin and myoglobin that is a ferrous derivative of protoporphyrin and readily oxidizes to hematin or hemin

called also protoheme

More from Merriam-Webster on heme

Britannica.com: Encyclopedia article about heme

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