These proteins have a direct active role in the chemical reactions of the cell. In the early stages of life, it seems that the first RNA chains would have had the dual role of self-replicating (as is today the case with DNA) and participating actively in the chemical reactions of the cell activity. Because of their dual role, these cells are called ribozymes (a contraction of the words ribosome and enzyme). But there is an important obstacle to the theory of ribozymes as the origin of life: they could not be very large in length as they would not be able to correct the replication errors (mutations). Therefore they were unable to contain enough genes even to develop the most simple organisms.
An investigation led by Mauro Santos, from the Department of Genetics and Microbiology at the Universitat Aut�noma de Barcelona (Spain), alongside two Hungarian scientists, has shown that the error threshold, that is, the maximum number of errors that may occur during the replication process of ribozymes without this affecting its functioning, is higher than was previously calculated. In practice, this means that the first riboorganisms (protocells in which RNA is responsible for genetic information and metabolic reactions) could have a much bigger genome than was previously thought: they could contain more than 100 different genes, each measuring 70 bases in length (bases are the units that constitute the genes and codify the information), or more than 70 genes, each measuring 100 bases. It is worth remembering t
Source:Universitat Autonoma de Barcelona