Evolution represents the change in the characteristics of a particular species over generations, which primarily depends upon the natural selection. Moreover, the theory of evolution relies on the idea that all species are related in a particular manner and they gradually change as time passes by. Along with that, evolution involves genetic variation in a specific population as a result of which the physical characteristics of an organism is altered. These physical characteristics of a particular species are referred to as a phenotype.
It is obvious that some of the characteristics might be advantageous for organisms living in a particular environment. The organisms that have characteristics suitable for that particular environment are expected to have a higher chance of survival and resistance to environmental danger (predators, food availability, diseases, etc.). As a result, the individuals that are better adapted to the environment are more likely to reproduce and pass on the genes to the next generation. So, such species are more likely to evolve gradually. According to Charles Darwin’s theory, this process is referred to as a natural selection.
But what has Biochemistry to do with evolution?
At first glance, it might seem that the process of evolution is simply linked with the ability of an organism to adapt to a particular environment. But, if we look deeply into this matter, we will identify various aspects of different living organisms that are connected to biochemical changes that alter the process of evolution.
While lots of issues involved in the evolutionary process are linked with Biochemistry, this article will emphasize several significant aspects of evolution that are examined by biochemists.
What is Evolutionary Biochemistry?
Evolutionary Biochemistry is the subfield of Biochemistry that examines the evolutionary processes that give rise to the diversity and heterogeneity of life on our planet. If Evolutionary Biology studies natural selection, common descent, or speciation, Evolutionary Biochemistry is more concerned with biochemical features that are involved in the evolutionary process. Such features include protein evolution, genetic alteration, mechanisms of mutations, physical properties of biological molecules, and changes in metabolism.
Considering the importance of the concepts mentioned above, it can be stated that Biochemistry provides the most significant evidence of evolution in living organisms. If not biochemical analysis and investigations, it would not have been possible to identify the sequence of amino acids in proteins, structural and functional characteristics of essential proteins present in living organisms, or genetic mutations that impact the DNA sequence of any living organism and cause different genetic disorders.
Evolution is the process through which populations of living organisms change as time passes by. But what underlies the changes? Genetic variations are the most critical factors that lead to evolution. Although genetics is the study of heredity which is a biological process, the proficiency in biochemical structure and function of genetic molecules is essential for a complete understanding of the process.
Moreover, evolutionary genetics is the subfield of genetics that examines the genetic variations that lead to evolutionary processes. Such modifications include the following issues: the evolution of genome structure and function, genetic basis of speciation and adaptation, genetic alterations within populations due to the natural selection.
As was already mentioned above, genetic variations can lead to evolutionary changes. These genetic variations can result from either gene mutations or genetic recombination. But not all mutations lead to evolution. The only mutations from which evolutionary changes can arise are referred to as hereditary mutations that are passed to future generations.
To examine the mutated genome sequence (altered nucleotide sequence) of an organism, it is of enormous importance to imply biochemical principles and methodologies. Structural Biochemistry is the field that studies the changes in nucleotide sequence along with its effects on the species themselves.
Gene mutations or genetic recombination can be one of the reasons for the alteration of protein function and activity, leading to the evolutionary traits in living organisms. This is because the DNA sequence determines the protein composition of a living organism.
Alterations in proteins lead to protein evolution which is considered as the primary indicator of the progression of protein structure and function over time. Since the process of protein evolution cannot be examined independently, Biochemistry plays a vital role in the investigation of the changes in particular proteins in a living organism.
Moreover, some of the changes in protein sequence might not alter the function of the protein. But in case if the role of the protein is altered due to the changes in its sequence, it is of huge importance to utilize biochemical principles and identify specific evolutionary relationships between the sequence and the function in a particular organism.
The scenario that suggests how the proteins might have evolved is not yet determined, but there are several theories regarding this issue. To identify the evolutionary process of a species, the involvement of Biochemistry is essential.
Enzymes are the proteins that act as biological catalysts that accelerate chemical reactions occurring in a living organism. Without the presence of different enzymes in an organism, many of the reactions would have been too slow for proper functioning.
The alteration of enzyme functions is directly linked to the changes in the amino acid sequence in proteins. As the protein sequence evolves, the enzymes might change their functions and activities.
Unfortunately, it is not quite possible to reconstruct the organism from which present-day organisms have evolved. But there are several mechanisms proposed which involve the study of functional properties of different enzymes in order to identify the possible route of evolution. Mutations and natural selection are the major factors that affect the evolutionary changes. Therefore, Biochemistry provides evidence of evolution in terms of modifications in various biological molecules, such as enzymes.
Hormones are chemicals that are made by glands and released into the bloodstream in order to send a signal to a particular part of the body. These agents of biological coordination of a living organism are responsible for influencing various phenotypic features. Similarly to all biological molecules that have evolved through time as a result of natural selection, hormones have also been altered.
Considering the fact that most of the aspects of the endocrine system are evolutionary conserved, the implication of possible evolutionary patterns can be studied through the examination of alterations in hormone production and secretion. For the complete investigation of the evolutionary processes via hormonal changes in living organisms, it is of huge importance to imply biochemical principles and methodologies.
Evolution of Metabolism
Metabolism is the set of anabolic (the synthesis of compounds) and catabolic (the breakdown of compounds) reactions that are essential for any living organism to maintain the living state. Metabolic pathways include various complex reactions that have been evolved from a universal ancestor, prokaryotic cell.
As a result of natural selection, metabolic pathways might have developed and enhanced to reach the optimal state as a solution to various metabolic problems. The reaction mechanism has evolved through time for the overall reaction to occur more efficiently and in fewer steps. These changes have led to the evolution of the reactions.
Various studies show the evidence of the evolution of metabolism, including but not limited to genomic studies, the examination of enzymes, and the studies of the evolution of protein structure involved in metabolic pathways.
In order to identify possible sources of the evolution of metabolic pathways, it is essential to bring into play Biochemistry.
To sum up, there cannot be a single reason or mechanism for evolutionary changes. There are several fields of science to be considered in order to identify the evidence of evolution. One of such areas can be considered to be Biochemistry since it is a mixture of Chemistry and Biology. The most efficient way to study different issues regarding the living organisms is to utilize biochemical principles since Biochemistry is all about the Chemistry of Life.
Biochemistry interconnects the biological compounds and their chemistry to accurately identify various mechanisms of action involved in a living organism. For that reason, it can be concluded that the evidence of evolution that Biochemistry provides is primarily connected to genetic information, protein evolution, enzymes, hormones, and metabolic pathways.
There are a lot more concepts that are associated with the field of Evolutionary Biochemistry. This article just emphasized several major shreds of evidence of evolution from the biochemical perspective.