Variation in how animals and bacteria use heme reveals potential target for new antibiotics The Impossible Whopper pictured at a Burger King restaurant in Columbus, Georgia. Burger King started offering this burger featuring a patty made with heme in August 2019. (Image: Shutterstock) May 11, 2021 SHARE It took an unlikely food innovation — earth-friendly vegetarian patties, made to taste and “bleed” like the familiar meaty ones — to make people aware of heme. But heme is an essential part of proteins found in most life forms, from tiny bacteria to soy plants to the human body. Heme plays a crucial role in supplying cells with the energy needed to carry out chemical reactions.