Naive Prediction of Protein Backbone Phi and Psi Dihedral Angles Using Deep Learning
Abstract
:1. Introduction
2. Results
2.1. Mean Absolute Prediction Error
2.2. Measured vs. Predicted Values
2.3. Dihedral Angle Predictability in Amino Acids
2.4. Three-State Secondary Structure Prediction
3. Materials and Methods
3.1. Dataset Preparation
3.2. Neural Network
3.3. Loss Function
3.4. Optimization
3.5. Predicted Outputs
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Sample Availability
Abbreviations
7PCP | 7 physicochemical properties |
AMD | Advanced Micro Devices |
ASA | accessible surface area |
B | isolated β-bridge |
BAP | protein backbone angle predictions |
BLAST | Basic Local Alignment Search Tool |
BRNN | bidirectional recurrent neural network |
C | carbon atom ooil |
CASP | Critical Assessment of protein Structure Prediction |
CNN | convolutional neural network |
CoDNas | Conformational Diversity of Native State |
Cα | alpha carbon atom |
DNN | deep neural network |
E | parallel/anti-parallel β sheet conformation |
E | sheet |
FCNN | fully connected neural network |
FM | free modeling |
G | 310 helix |
H | α-helix |
HHBlits | HMM-HMM-based lightning-fast iterative sequence search |
HMM | hidden Markov model |
I | π-helix |
LSTM | long short-term memory |
LSTM-BRNNs | long short-term memory and bidirectional recurrent neural networks |
MAE | mean absolute error |
MD | molecular dynamics |
MTS | mitoargetingtargetting sequence |
MnSOD | manganese superoxide dismutase |
N | nitrogen atom |
PDB | Protein Data Bank |
PISCES | Protein sequence culling server |
PSP | protein structure prediction |
PSSM | position-specific scoring matrix |
PSSP | protein secondary structure prediction |
Q3 | three-state model |
Q8 | eight-state model |
R-free | Free R-value |
RMSE | root mean squared error |
ReLU | Rectified Linear Unit |
ResNets | Residual Networks |
ResNets | residual networks |
S | bend |
SAP | structure analysis and prediction |
SNP | single nucleotide polymorphism |
SS | secondary structure |
SSPro | Secondary Structure Prediction |
SVM | support vector machine |
T | turn |
Å | Angstrom |
τ | tao |
ψ | psi dihedral angle |
ω | omega dihedral angle |
ϕ | phi dihedral angle |
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SS Label | Helix (Predicted) | Sheet (Predicted) | Undesignated (Predicted) |
---|---|---|---|
Helix (real) | 73.2% (141,380) | 16.0% (30,837) | 10.8% (20,908) |
Sheet (real) | 14.9% (33,535) | 73.9% (166,673) | 11.2% (25,300) |
Undesignated (real) | 27.1% (23,151) | 26.8% (22,905) | 46.1% (39,335) |
Sliding Window | Phi MAE [deg] | Psi MAE [deg] | Epoch Duration [s] |
---|---|---|---|
3 | 28.37 | 64.09 | 57 |
7 | 25.67 | 53.36 | 102 |
11 | 24.51 | 48.98 | 130 |
15 | 23.96 | 46.74 | 155 |
21 | 23.53 | 44.14 | 210 |
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Broz, M.; Jukič, M.; Bren, U. Naive Prediction of Protein Backbone Phi and Psi Dihedral Angles Using Deep Learning. Molecules 2023, 28, 7046. https://doi.org/10.3390/molecules28207046
Broz M, Jukič M, Bren U. Naive Prediction of Protein Backbone Phi and Psi Dihedral Angles Using Deep Learning. Molecules. 2023; 28(20):7046. https://doi.org/10.3390/molecules28207046
Chicago/Turabian StyleBroz, Matic, Marko Jukič, and Urban Bren. 2023. "Naive Prediction of Protein Backbone Phi and Psi Dihedral Angles Using Deep Learning" Molecules 28, no. 20: 7046. https://doi.org/10.3390/molecules28207046
APA StyleBroz, M., Jukič, M., & Bren, U. (2023). Naive Prediction of Protein Backbone Phi and Psi Dihedral Angles Using Deep Learning. Molecules, 28(20), 7046. https://doi.org/10.3390/molecules28207046