How Do Molecules Store Information to Manufacture Protein Molecules?

Proteins are an essential class of biological molecules that perform a wide range of functions in living organisms. They are responsible for carrying out many of the cellular processes necessary for life, including providing structural support, transporting molecules, and regulating gene expression. One of the most fascinating aspects of proteins is the way they are manufactured, starting with the storage of genetic information in the form of molecules.

Storage of Genetic Information

Genetic information is stored in a molecule called deoxyribonucleic acid (DNA), which contains all the instructions necessary to build an organism. DNA is composed of four different nucleotide bases – adenine (A), cytosine (C), guanine (G), and thymine (T) – that are arranged in a specific sequence that encodes genetic information.

The sequence of nucleotide bases in DNA is replicated and transmitted from generation to generation through a process known as DNA replication. During replication, the DNA molecule unwinds, and nucleotides are added to each strand according to the complementary base-pairing rules (A pairs with T, and C pairs with G), resulting in two identical copies of the original DNA molecule.

Transcription and Translation

The genetic information stored in DNA is not used directly to build proteins. Instead, the information is transcribed into a molecule called ribonucleic acid (RNA), which functions as a messenger between DNA and the protein-building machinery of the cell.

RNA is composed of nucleotide bases similar to those found in DNA, but with one key difference – the base thymine is replaced by a similar base called uracil (U). During transcription, the DNA molecule unwinds, and a complementary RNA molecule is synthesized using the base-pairing rules (A pairs with U, and C pairs with G).

Once the RNA molecule has been synthesized, it undergoes a process called translation, in which the sequence of RNA bases is used to assemble a protein molecule. A protein is made up of amino acid building blocks, and each amino acid is specified by a sequence of three RNA bases known as a codon.

During translation, the ribosome – a complex molecular machine – reads the sequence of codons in the RNA molecule and recruits the appropriate amino acids to build the protein molecule. The process continues until a stop codon is encountered, at which point the newly synthesized protein is released from the ribosome.

Conclusion

In summary, the information necessary to manufacture protein molecules is stored in the sequence of nucleotide bases in DNA. This information is transcribed into RNA, which serves as a messenger between DNA and the protein-building machinery of the cell. Through a process called translation, the sequence of RNA bases is used to assemble the amino acids that make up a protein molecule. The ability to store and use genetic information in this way is a fundamental property of life and is essential for the diversity and complexity of the living world.