Genetic code definition

Fig. 1.5 Schematic representation of the evolution of life from its precursors, on the basis of the definition of life given by the authors. If bioenergetic mechanisms have developed via autonomous systems, the thermodynamic basis for the beginning of the archiving of information, and thus for a one-polymer world such as the RNA world , has been set up. Several models for this transition have been discussed. This phase of development is possibly the starting point for the process of Darwinian evolution (with reproduction, variation and heredity), but still without any separation between genotype and phenotype. According to the authors definition, life begins in exactly that moment when the genetic code comes into play, i.e., in the transition from a one-polymer world to a two-polymer world . The last phase, open-ended evolution, then follows. After Ruiz-Mirazo et al. (2004)...

Automated polymer-based synthesis comes into its own when a stepwise polymerization is required with precise control over the addition of particular monomers in a specific sequence. This is almost a definition of peptide synthesis, Nature attaches each amino acid to a different polymer (transfer RNA) and uses a computer program (the genetic code) to assemble the polymers in the right order so that the amino acids can be joined together while bound to another polymer (a ribosome). No protection of any functional groups is necessary in this process. 

By definition, a sense peptide is one whose sequence is coded for by the nucleotide sequence (read 5 3 ) of sense mRNA, whose sequence contains the same coding information as the sense strand of DNA. Gonversely, a complementary peptide is coded for by the nucleotide sequence (read 5 3 ) of complementary mRNA, with the same sequence information as the complementary strand of DNA. Frequently, sense and complementary peptides are capable of specific interactions, in a process that may involve an amino-acid interaction code embedded within the genetic code and its complement (Figure 7.40). One application of sense-complementary peptide interactions may be in the design of complementary... 

Simple Definition. The primary structure of a protein is dictated by its genetic code. All the proteins from the genome constitute the proteome. After translation, the proteome is covalently modified by a variety of small molecules of exogenous or endogenous origin, and also by other proteins or peptides. The event is defined as the protein posttranslational modification. ... 

The three covalent biomacromolecules share some similarities in their global structures but differ in their cellnlar functions and structural details. DNA is the carrier of genetic information, which mnst be faithfully duplicated and selectively transcribed so that each cell can synthesize the proteins it needs. RNA functions mainly in the transcription and translation of this information. In order that the nucleic acids may convey genetic information, a pattern or code must be incorporated in their chemical structure. Purine and pyrimidine bases are arranged in a definite sequence and this sequence constitutes the genetic code. 

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