Related Experiment Video
Updated: Jul 17, 2026
16:41
A Protocol for Computer-Based Protein Structure and Function Prediction
Published on: November 3, 2011
Protein secondary structure prediction with semi Markov HMMs
Zafer Aydin1, Yucel Altunbasak, Mark Borodovsky
1Center for Signal & Image Process., Georgia Inst. of Technol., Atlanta, GA, USA.
Summary
This study enhances protein secondary structure prediction using a novel semi-Markov hidden Markov model (HMM). The improved model achieves a 1.5% accuracy increase in predicting protein structures from single sequences.
Area of Science:
- Bioinformatics
- Computational Biology
- Structural Biology
Background:
- Secondary structure prediction is crucial for understanding protein structure and function.
- Current prediction methods approach a theoretical accuracy limit of 88%.
- Two main approaches exist: ab initio (single sequence) and homology-based prediction.
Purpose of the Study:
- To improve ab initio (single sequence) secondary structure prediction accuracy.
- To develop a more effective semi-Markov hidden Markov model (HMM) for this task.
Main Methods:
- Developed a semi-Markov HMM incorporating statistically significant amino acid correlation patterns at segment borders.
- Introduced an internal dependency model to capture right-to-left dependencies within the HMM.
- Implemented an iterative training method for improved HMM parameter estimation.
Main Results:
- Achieved a 1.5% improvement in three-state-per-residue accuracy for secondary structure prediction.
- The novel dependency models and training method contributed to the accuracy enhancement.
Conclusions:
- The proposed semi-Markov HMM offers a significant advancement in single-sequence protein secondary structure prediction.
- The integration of segment border dependencies and iterative training effectively boosts prediction accuracy.
Related Concept Videos
01:22Protein Folding
Overview
01:22Protein Folding
Overview
01:25Protein Folding
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
01:13Protein Organization
Overview
01:24Protein Organization
Proteins are polymers of amino acid residues. They are versatile and responsible for different cellular functions, including DNA replication, molecular transport, catalysis, and structural support. Proteins have a hierarchical structure comprising at least three levels of organization: primary, secondary, and tertiary structure. Some large proteins have a quaternary structure where individual protein subunits are linked together.
The primary structure of a protein is its amino acid sequence.
The primary structure of a protein is its amino acid sequence.
02:15Protein and Protein Structure
Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme can...
A protein's shape is critical to its function. For example, an enzyme can...