What is the Difference Between Protein Subunit and Domain?
🆚 Go to Comparative Table 🆚The main difference between protein subunits and domains lies in their structure and role within a protein. Here are the key differences:
- Protein Subunit: A protein subunit is a separate polypeptide chain of a protein that assembles with other subunits to form a larger protein complex. It is a distinct individual component of a larger multimeric protein. Subunits can have domains, and they are relatively larger in size than domains. Examples of subunits include the alpha and beta subunits of hemoglobin and larger subunits of ribosomes.
- Protein Domain: A protein domain is a contiguous region of the polypeptide chain of a protein that frequently folds locally and functions as a semi-independent unit. It is a distinct, independently folding region within a protein or nucleic acid molecule. Domains are typically composed of a continuous segment of the polypeptide chain and often possess specific functions or activities. Examples of protein domains include the DNA binding domain, kinase domain, and SH2 domain.
Similarities between protein subunits and domains include:
- Both are structural units of a multimeric protein.
- Both are made up of amino acids.
- They are connected to the term "polypeptide chain".
- They are both extremely important for the overall function of the protein.
In summary, protein domains are specific, independently folding units within a protein, while subunits are the individual polypeptide chains that come together to form a larger protein complex. Both play crucial roles in the structure and function of proteins.
Comparative Table: Protein Subunit vs Domain
Here is a table summarizing the differences between protein subunits and domains:
| Feature | Protein Subunit | Protein Domain |
|---|---|---|
| Definition | A protein subunit is a separate polypeptide chain of a protein that assembles with other subunits to form a multimeric protein. | A protein domain is a contiguous region of the polypeptide chain of a protein that frequently folds locally and functions as a semi-independent unit. |
| Size | Larger than a protein domain. | Smaller than a protein subunit. |
| Function | Protein subunits work together to perform a specific function. | Protein domains provide proteins with specific functions through precise three-dimensional structures. |
| Structure | Subunits are responsible for the tertiary structure of a protein. | Domains are elements of the protein's overall structure that are stable and often fold independently of the rest of the protein. |
In summary, protein subunits are separate polypeptide chains that assemble to form multimeric proteins, while protein domains are contiguous regions of the polypeptide chain that fold locally and function semi-independently. Subunits are larger than domains and are responsible for the tertiary structure of a protein, while domains contribute to the protein's overall structure and function.
- Polypeptide vs Protein
- Motif vs Domain
- Kingdom vs Domain
- Peptide vs Protein
- Gene vs Protein
- Amino Acid vs Protein
- Amino Acid vs Protein
- DNA vs Protein Sequence
- Simple Protein vs Conjugated Protein
- Enzyme vs Protein
- Substrate vs Active Site
- Whey Protein vs Protein
- Recombinant DNA vs Recombinant Protein
- Proteasome vs Protease
- Active Directory vs Domain
- Protease vs Proteinase
- Domain vs Hosting
- Domain vs Range
- Folded vs Unfolded Protein