Difference between Nucleic Acids and Proteins
In this post, we will know about the key differences between Nucleic Acids and Proteins. After reading this post, you can perfectly differentiate the two of these very clearly.
Make sure to read this complete post to understand the topic very clearly and precisely.
Both proteins and nucleic acids are biomacromolecules because they are large biological molecules composed of thousands of covalently connected atoms.
Biomacromolecules like proteins and nucleic acids are formed by many monomers linking together, forming a polymer.
And moreover, those molecules that have a molecular weight of more than 1000 Dalton are called biomacromolecules.
Nucleic acids are linear polymers (chains) of nucleotides whereas, proteins are polymers made up of amino acids.
Proteins have many different functions and they are used in the biological body for providing structural support, facilitate storage, cell transport, cellular communication, cellular movement, defense, signaling, and more.
Nucleic acids transmit and help express hereditary information from generation after generation. There are two types of nucleic acids: DNA (Deoxyribonucleic Acids) and RNA (Ribonucleic Acids).
Although both look different and act differently, nucleic acids do contain the same elements as proteins: carbon, hydrogen, oxygen, nitrogen, and phosphorus or sulphur in some.
Let’s know more about them with precise detail and comparison…
Comparison Chart: Nucleic Acids Vs. Proteins
| NO. | NUCLEIC ACIDS | PROTEINS |
|---|---|---|
| 1. | Nucleic acids are long-chained organic molecules that are made up of nucleotides. | Proteins are long-chained organic molecules that are made up of amino acids. |
| 2. | Nucleotides are the monomers that make up the nucleic acids. | Amino acids are the monomers that make up the proteins. |
| 3. | There are 5 types of nucleotides that make nucleic acids. | There are 21 types of amino acids that make proteins. |
| 4. | There are 2 types of nucleic acids: DNA & RNA. | There are 80,000 to 400,000 different varieties of proteins. |
| 5. | A nucleotide consists of three components: a sugar molecular, a phosphate group, and any of the 5 nitrogenous bases (A, G, C, T, U). | An amino acid is made up of a basic amino group (−NH2), an acidic carboxyl group (−COOH), and an organic R group that is unique to each amino acid. |
| 6. | Made up of carbon, hydrogen, nitrogen, oxygen, and phosphorus or sulfur. | Also made up of carbon, hydrogen, nitrogen, oxygen, and phosphorus/sulfur. |
| 7. | Phospho-diester bonds occur in its formation. | Peptide bonds occur in its formation. |
| 8. | These are hereditary in nature. | These are non-hereditary in nature. |
| 9. | They take part in gene expression. | They take part in cell storage, cell signaling, structural support, provide defense, make enzymes, cell transportation, make cell receptors, perform enzymatic actions, etc. |
| 10. | Coding DNA sequences codes for amino acids of proteins. | Each protein is formed from a codon which is a sequence of three DNA or RNA nucleotides that corresponds with a specific amino acid. |
| 11. | Non-coding DNA sequences do not code for amino acids of proteins. | Coding DNA sequences contain 61 codons that code for 20 amino acids, and 3 codons: UAA, UAG, UGA that do not code for amino acids. |
Definition of Nucleic Acids
We all know DNA & RNA, right? These are the nucleic acids. DNA is Deoxyribonucleic acid whereas, RNA is Ribonucleic acid.
The building block of nucleic acids is a nucleotide. A nucleotide consists of three components: a sugar molecular, a phosphate group, and a nitrogenous base.
Yes, nucleic acids i.e the DNA & RNA are polymers of nucleotides. In both DNA & RNA, the monomers are known as nucleotides. All of the nucleotides combine together to form a polynucleotide. The polynucleotide is the polymer of many nucleotides.
Each nucleotide in DNA is formed of a Deoxyribose Pentose Sugar, a Phosphate Group, and one of any four Nitrogenous bases: Adenine(A), Guanine(G), Cytosine(C), and Thymine(T).
And, each nucleotide in RNA is formed of a Ribose Pentose Sugar, a Phosphate Group, and one of any four Nitrogenous bases: Adenine(A), Guanine(G), Cytosine(C), and Uracil(U).
Nucleic acids hold the capacity to replicate itself and gets passed to offspring during reproduction. They are the prime reason for gene expression and protein synthesis.
The genotypic characteristics of organisms depend directly on nucleic acids. And these nucleic acids hold the information on why, how, when, and where to create proteins in the living body.
Nucleic acids are generally very large molecules. Indeed, DNA molecules are probably the largest individual molecules known. RNA is much shorter than DNA.
Example of Nucleic Acids: Human Chromosome 1 is a single DNA molecule that contains 247 million base pairs. Another one is small molecules like siRNA (small interfering RNA) that consists of 21 nucleotides only.
Definition of Proteins
Each protein is a polymer of amino acids. As there are 21 types of amino acids (for example: alanine, cysteine, lysine, etc.), a protein is a heteropolymer and not a homopolymer.
A homopolymer has only one type of repeating monomer. Whereas, a heteropolymer like protein has several types of repeating monomer (amino acids).
A peptide is a compound consisting of two or more amino acids. And proteins are polypeptides that consist of 50 or more amino acids.
Proteins are macromolecules formed by polypeptide chains of amino acids. A protein contains at least one or more polypeptides. Therefore, proteins are long chains of amino acids held together by peptide bonds.
On average, each eukaryotic protein has an average size that includes about 472 amino acids attached together, whereas a bacterial protein can have about 283 amino acids.
Amino acids that make up the proteins can be essential or non-essential ones.
The amino acids that our body can make are non-essential, and those amino acids that our body can’t make and so needs to supplied through diet are called essential amino acids.
Proteins carry out many functions in living organisms like, some transport nutrients across cell membrane, some fight infections, some work as hormones, some are enzymes, and a lot more.
Example of Proteins: Collagen is the most abundant protein in the animal kingdom, and RUBISCO is the most abundant protein in the whole biosphere.
Key Differences Between Nucleic Acids and Proteins
1. Both nucleic acids and proteins are biomacromolecules. Proteins are smaller and lighter than both DNA & RNA. Each protein can have around a hundred to several thousand amino acids. A single nucleic acid like DNA can contain a minimum of 48 million nucleotides.
2. The coordination of three nucleotides sequence makes a codon that will code for a specific amnio amino acid. This means that the nucleic acids like DNA & RNA hold genetic information and produce proteins. Proteins express the genetic characteristics in the living body. This means that the job of the nucleic acids is to make proteins and the job of proteins is to express the genetic information.
3. The phenotypic characteristics of organisms depend directly on proteins. And, the genotypic characteristics of organisms depend directly on nucleic acids. The gene expression process relates the phenotypic and genotypic characteristics together as nucleic acids take part in protein synthesis.
4. Nucleic acid is a polymer of nucleotides whereas, proteins are polymers of amino acids.
5. A single amino acid in a protein has an amino group, an acidic carboxyl group, and an organic R group. Whereas, a single nucleotide in a protein has a sugar molecular, a phosphate group, and a nitrogenous base.
6. Proteins can’t be inherited and they don’t carry any genetic information. Whereas, nucleic acids are heritable from generation after generation and they do carry genetic information.
7. Proteins are present almost everywhere, where nucleic acids aren’t. Whereas, nucleic acids like DNA are present in the nucleolus of the cell, RNA in the cytoplasm and nucleus of the cell.
Conclusion
Nucleic acids (DNA & RNA) and Proteins are two of the most essential biomolecules for every living body.
Both play an important role in the gene expression mechanism that can be better understood via. the Central Dogma Model of Biology.
It’s the arrangement of the nitrogenous bases in the polynucleotide that stores the information to code for amino acids of the proteins.
So, nucleic acids (DNA & RNA) are the factory that produces (expresses) genetic information in the form of amino acids. These amino acids are the building blocks of proteins that brings those genetic changes phenotypically.