polymerase ribozyme Archives - Astrobiology

Predicted secondary structure of QT45 ribozyme with nucleotide color corresponding to fitness for each of the three possible single mutations at each position, displayed in the same order as the three representative mutations shown and colored as in Fig. 2E. Base pair annotations are provided, where the upper rectangle connecting two bases shows the average fitness or epistasis of measured base pair-breaking double mutations. For canonical base pairs, the inner small rectangles show (from left to right) the fitness or epistasis of mutations to base pairs UG, UA, GC, CG, AU, GU. For the non-canonical base pair C11-U35, the base pairs shown are UG, UA, GC, UC, CU, CG, AU, GU. (A) Base pair annotations are colored according to fitness. Base pair-retaining mutations generally have higher fitness than base pair-breaking mutations. (B) Base pair annotations are colored according to epistasis. Base pair-retaining mutations generally show more positive epistasis compared to base pair-breaking mutations. -- Science

Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life, Status Report

A Small Polymerase Ribozyme That Can Synthesize Itself And Its Complementary Strand

by Keith CowingFebruary 16, 2026February 16, 2026

The emergence of a chemical system capable of self-replication and evolution is a critical event in the origin of life.