Biology’s Four-Letter DNA Alphabet Just Expanded to Eight

All known life uses 4 DNA letters; UC San Diego showed an existing bacterial enzyme can accurately read and transcribe 8, doubling the genetic alphabet with synthetic letters

Experiments & Discoveries News: All life on Earth, from bacteria to blue whales, writes its genetic instructions using the same four-letter alphabet. These four DNA bases, usually re.

An E. coli enzyme transcribed a DNA template carrying a synthetic letter that no known organism uses, and the redesigned version of that letter substantially reduced the original's mispairing with guanine but also slowed that one incorporation step, because the nitro group responsible for the errors appears to be the one that helps the enzyme close on the incoming base

Four cryo-electron microscopy structures at 2.42 to 2.75 angstroms show the P-with-Z pair, in both its original and its redesigned form, sitting in the polymerase's active site in ordinary Watson-Crick geometry, and the gel kinetics supply an awkward corollary.

Natural Enzyme Successfully Reads an Eight-Letter DNA Alphabet

All known life on Earth stores genetic information using the same four-letter DNA alphabet. Researchers have now shown that one of biology’s most important enzymes can accurately read an artificial DNA system containing eight letters. The discovery suggests that the natural machinery inside living cells may be able to work with a much larger genetic […]