Читать книгу Astrobiology - Charles S. Cockell - Страница 112

There are a few remarkable things about this process worth mentioning. First, the table of codons shown in Figure 5.12, bar some minor modifications in some organisms, is essentially universal to all life forms. This not only shows the great antiquity of the genetic code, but also strongly suggests that all life on Earth was derived from a single common ancestor in which this code first emerged, presumably from more simple codes and structures that preceded it.

Second, the table is astounding because it is a code that allows a one-dimensional piece of information – the strand of a DNA molecule – to be transformed into the three-dimensional structure of a chemically active molecule. How did the structures emerge and what was the evolutionary process that linked one-dimensional information storage to three-dimensional biological function? This is one of the most fascinating questions in astrobiology, linked explicitly into our attempts to understand the origin of life. We come back to this when we consider the origin of life.