Life is Left-Handed on Earth (Caution: Geeky Content)

"Why Life on Earth is Left-Handed"
Space.com (March 23, 2009)

"A mystery has long surrounded the 'left-handed' bias in the building blocks of life. Now scientists have confirmed the same left-handed bias in meteorites, which may suggest that life on Earth originated from space rocks.

"That bias exists in amino acids, the basic components of proteins, which can come in a left-handed or right-handed configuration. Left-handed or right-handed life can only break down and use their respective amino acids, which means that left-handed life could have gained an advantage in an Earth environment with more left-handed amino acids.

"Researchers examined meteorites dating back more than 4.5 billion years, or older than Earth's existence as a planet, and found that meteorites with the longest exposures to water within had a much stronger left-handed bias...."

Okay: so life on Earth may be 'left-handed' because it's damp. Quite possible.

This left-handed/right-handed stuff isn't as impractical as it sounds: but its applications are a bit limited. Mostly it's pharmacological researchers, biochemists, and people who give a rip about their vitamin supplements who are interested.

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Related posts, at

• "A Serious Search for Other Worlds, Life, and - Maybe - Extra-Terrestrial Intelligence"