The general notion of an “RNA world” is that, in the early development of life on the Earth,
genetic continuity was assured by the replication of RNA, and RNA molecules were the chief …

The general notion of an “RNA World” is that, in the early development of life on the Earth,
genetic continuity was assured by the replication of RNA and genetically encoded proteins …

Single-particle cryogenic electron microscopy (cryo-EM) has become a standard technique
for determining protein structures at atomic resolution,–. However, cryo-EM studies of protein …

In nuclear pre-messenger RNA splicing, introns are excised by the spliceosome, a dynamic
machine composed of both proteins and small nuclear RNAs (snRNAs). Over thirty years …

Phosphoryl-transfer reactions are central to biology. These reactions also have some of the
slowest nonenzymatic rates and thus require enormous rate accelerations from biological …

DNA synthesis has been extensively studied, but the chemical reaction itself has not been
visualized. Here we follow the course of phosphodiester bond formation using time-resolved …

It is becoming increasingly clear that RNA is more than a passive carrier of genetic
information. Folded RNA molecules play key roles in almost every aspect of cellular …

The discovery of the RNA self-splicing group I intron provided the first demonstration that not
all enzymes are proteins. Here we report the X-ray crystal structure (3.1-Å resolution) of a …

Many protein enzymes use general acid-base catalysis as a way to increase reaction rates.
The amino acid histidine is optimized for this function because it has ap K a (where K a is the …

The natural RNA enzymes catalyse phosphate-group transfer and peptide-bond formation.
Initially, metal ions were proposed to supply the chemical versatility that nucleotides lack. In …