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Life before proteins

Early cells could have acquired nutrients through fat molecule membranes

Long before chickens or eggs, life had to solve a difficult chicken-and-egg problem.

The first cells to arise on the primordial Earth needed nutrients from their surroundings in order to grow and reproduce long enough to evolve complex proteins. Yet the membranes that encapsulate modern cells need complex proteins to act as pores that let these nutrients pass into the cells. Presumably, primitive cells wouldn’t have had these sophisticated pore proteins, so scientists have wondered how the first living cells managed to get nutrients from their environment.

In trying to make simple artificial cells from scratch, researchers have found a plausible way around this dilemma. By making artificial membranes from various combinations of fat molecules different from those in modern cell membranes, the scientists discovered recipes for membranes that allow nutrients to pass into the cells.

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