Structural Bioinformatics
Homology Modeling vs ab initio Protein Structure Prediction
In one of our previous articles, we explained the basic methodology involved in the homology modeling of a protein. In this article, we are going to compare the two methods of protein structure prediction: Homology modeling & ab initio prediction.
Both types of methods have their own merits and demerits. It completely depends upon your study which method you select for structure prediction.
Basic Comparison
This is the basic comparison between the widely used methods of protein structure prediction.
| Parameters | Homology Modeling | Ab initio Prediction |
| Criteria | Similarity >= 30-32% | Similarity <= 30-32% |
| Structural details | Unknown | Unknown |
| Homology Search | Performed | Not performed |
| Template search | Performed | Not performed |
| Template-based prediction | Yes | No |
| Structure Validation | Performed | Performed |
| Structure Quality | Depends upon the algorithm used. | Depends upon the algorithm used. |
| Most widely used Software | Swissmodel | I-Tasser |
| Advantage | More accurate if shows high similarity with the template. | More precise |
| Disadvantage | Not precise in case of low similarity with the template |
Might not be accurate. |
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