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Arega AM, Dhal AK, Pattanaik KP, Nayak S, Mahapatra RK. An Immunoinformatics-Based Study of Mycobacterium tuberculosis Region of Difference-2 Uncharacterized Protein (Rv1987) as a Potential Subunit Vaccine Candidate for Preliminary Ex Vivo Analysis. Appl Biochem Biotechnol 2024; 196:2367-2395. [PMID: 37498378 DOI: 10.1007/s12010-023-04658-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/04/2023] [Indexed: 07/28/2023]
Abstract
Mycobacterium tuberculosis (Mtb) is the pathogen that causes tuberculosis and develops resistance to many of the existing drugs. The sole licensed TB vaccine, BCG, is unable to provide a comprehensive defense. So, it is crucial to maintain the immunological response to eliminate tuberculosis. Our previous in silico study reported five uncharacterized proteins as potential vaccine antigens. In this article, we considered the uncharacterized Mtb H37Rv regions of difference (RD-2) Rv1987 protein as a promising vaccine candidate. The vaccine quality of the protein was analyzed using reverse vaccinology and immunoinformatics-based quality-checking parameters followed by an ex vivo preliminary investigation. In silico analysis of Rv1987 protein predicted it as surface localized, secretory, single helix, antigenic, non-allergenic, and non-homologous to the host protein. Immunoinformatics analysis of Rv1987 by CD4 + and CD8 + T-cells via MHC-I and MHC-II binding affinity and presence of B-cell epitope predicted its immunogenicity. The docked complex analysis of the 3D model structure of the protein with immune cell receptor TLR-4 revealed the protein's capability for potential interaction. Furthermore, the target protein-encoded gene Rv1987 was cloned, over-expressed, purified, and analyzed by mass spectrometry (MS) to report the target peptides. The qRT-PCR gene expression analysis shows that it is capable of activating macrophages and significantly increasing the production of a number of key cytokines (TNF-α, IL-1β, and IL-10). Our in-silico analysis and ex vivo preliminary investigations revealed the immunogenic potential of the target protein. These findings suggest that the Rv1987 be undertaken as a potent subunit vaccine antigen and that further animal model immuno-modulation studies would boost the novel TB vaccine discovery and/or BCG vaccine supplement pipeline.
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Affiliation(s)
- Aregitu Mekuriaw Arega
- School of Biotechnology, KIIT Deemed to Be University, Bhubaneswar, Odisha, India
- National Veterinary Institute, Debre Zeit, Ethiopia
| | - Ajit Kumar Dhal
- School of Biotechnology, KIIT Deemed to Be University, Bhubaneswar, Odisha, India
| | | | - Sasmita Nayak
- School of Biotechnology, KIIT Deemed to Be University, Bhubaneswar, Odisha, India
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2
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Protein model accuracy estimation empowered by deep learning and inter-residue distance prediction in CASP14. Sci Rep 2021; 11:10943. [PMID: 34035363 PMCID: PMC8149836 DOI: 10.1038/s41598-021-90303-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 05/10/2021] [Indexed: 11/28/2022] Open
Abstract
The inter-residue contact prediction and deep learning showed the promise to improve the estimation of protein model accuracy (EMA) in the 13th Critical Assessment of Protein Structure Prediction (CASP13). To further leverage the improved inter-residue distance predictions to enhance EMA, during the 2020 CASP14 experiment, we integrated several new inter-residue distance features with the existing model quality assessment features in several deep learning methods to predict the quality of protein structural models. According to the evaluation of performance in selecting the best model from the models of CASP14 targets, our three multi-model predictors of estimating model accuracy (MULTICOM-CONSTRUCT, MULTICOM-AI, and MULTICOM-CLUSTER) achieve the averaged loss of 0.073, 0.079, and 0.081, respectively, in terms of the global distance test score (GDT-TS). The three methods are ranked first, second, and third out of all 68 CASP14 predictors. MULTICOM-DEEP, the single-model predictor of estimating model accuracy (EMA), is ranked within top 10 among all the single-model EMA methods according to GDT-TS score loss. The results demonstrate that inter-residue distance features are valuable inputs for deep learning to predict the quality of protein structural models. However, larger training datasets and better ways of leveraging inter-residue distance information are needed to fully explore its potentials.
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Ouyang J, Huang N, Jiang Y. A single-model quality assessment method for poor quality protein structure. BMC Bioinformatics 2020; 21:157. [PMID: 32334508 PMCID: PMC7183596 DOI: 10.1186/s12859-020-3499-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 04/15/2020] [Indexed: 11/13/2022] Open
Abstract
Background Quality assessment of protein tertiary structure prediction models, in which structures of the best quality are selected from decoys, is a major challenge in protein structure prediction, and is crucial to determine a model’s utility and potential applications. Estimating the quality of a single model predicts the model’s quality based on the single model itself. In general, the Pearson correlation value of the quality assessment method increases in tandem with an increase in the quality of the model pool. However, there is no consensus regarding the best method to select a few good models from the poor quality model pool. Results We introduce a novel single-model quality assessment method for poor quality models that uses simple linear combinations of six features. We perform weighted search and linear regression on a large dataset of models from the 12th Critical Assessment of Protein Structure Prediction (CASP12) and benchmark the results on CASP13 models. We demonstrate that our method achieves outstanding performance on poor quality models. Conclusions According to results of poor protein structure assessment based on six features, contact prediction and relying on fewer prediction features can improve selection accuracy.
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Conover M, Staples M, Si D, Sun M, Cao R. AngularQA: Protein Model Quality Assessment with LSTM Networks. COMPUTATIONAL AND MATHEMATICAL BIOPHYSICS 2019. [DOI: 10.1515/cmb-2019-0001] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Abstract
Quality Assessment (QA) plays an important role in protein structure prediction. Traditional multimodel QA method usually suffer from searching databases or comparing with other models for making predictions, which usually fail when the poor quality models dominate the model pool. We propose a novel protein single-model QA method which is built on a new representation that converts raw atom information into a series of carbon-alpha (Cα) atoms with side-chain information, defined by their dihedral angles and bond lengths to the prior residue. An LSTM network is used to predict the quality by treating each amino acid as a time-step and consider the final value returned by the LSTM cells. To the best of our knowledge, this is the first time anyone has attempted to use an LSTM model on the QA problem; furthermore, we use a new representation which has not been studied for QA. In addition to angles, we make use of sequence properties like secondary structure parsed from protein structure at each time-step without using any database, which is different than all existed QA methods. Our model achieves an overall correlation of 0.651 on the CASP12 testing dataset. Our experiment points out new directions for QA problem and our method could be widely used for protein structure prediction problem. The software is freely available at GitHub: https://github.com/caorenzhi/AngularQA
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Affiliation(s)
- Matthew Conover
- Department of Computer Science , Pacific Lutheran University , Tacoma , WA 98447 , USA
| | - Max Staples
- Department of Computer Science , Pacific Lutheran University , Tacoma , WA 98447 , USA
| | - Dong Si
- Division of Computing and Software Systems , University of Washington-Bothell , Bothell , WA 98011 , USA
| | - Miao Sun
- JingChi, Sunnyvale , CA 94089 , USA
| | - Renzhi Cao
- Department of Computer Science , Pacific Lutheran University , Tacoma , WA 98447 , USA
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5
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Wei HH, Yang W, Tang H, Lin H. The Development of Machine Learning Methods in Cell-Penetrating Peptides Identification: A Brief Review. Curr Drug Metab 2019; 20:217-223. [DOI: 10.2174/1389200219666181010114750] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 05/21/2018] [Accepted: 08/02/2018] [Indexed: 11/22/2022]
Abstract
Background:Cell-penetrating Peptides (CPPs) are important short peptides that facilitate cellular intake or uptake of various molecules. CPPs can transport drug molecules through the plasma membrane and send these molecules to different cellular organelles. Thus, CPP identification and related mechanisms have been extensively explored. In order to reveal the penetration mechanisms of a large number of CPPs, it is necessary to develop convenient and fast methods for CPPs identification.Methods:Biochemical experiments can provide precise details for accurately identifying CPP, but these methods are expensive and laborious. To overcome these disadvantages, several computational methods have been developed to identify CPPs. We have performed review on the development of machine learning methods in CPP identification. This review provides an insight into CPP identification.Results:We summarized the machine learning-based CPP identification methods and compared the construction strategies of 11 different computational methods. Furthermore, we pointed out the limitations and difficulties in predicting CPPs.Conclusion:In this review, the last studies on CPP identification using machine learning method were reported. We also discussed the future development direction of CPP recognition with computational methods.
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Affiliation(s)
- Huan-Huan Wei
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu, China
| | - Wuritu Yang
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu, China
| | - Hua Tang
- Department of Pathophysiology, Southwest Medical University, Luzhou, China
| | - Hao Lin
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu, China
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Olaya C, Adhikari B, Raikhy G, Cheng J, Pappu HR. Identification and localization of Tospovirus genus-wide conserved residues in 3D models of the nucleocapsid and the silencing suppressor proteins. Virol J 2019; 16:7. [PMID: 30634979 PMCID: PMC6330412 DOI: 10.1186/s12985-018-1106-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 10/16/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Tospoviruses (genus Tospovirus, family Peribunyaviridae, order Bunyavirales) cause significant losses to a wide range of agronomic and horticultural crops worldwide. Identification and characterization of specific sequences and motifs that are critical for virus infection and pathogenicity could provide useful insights and targets for engineering virus resistance that is potentially both broad spectrum and durable. Tomato spotted wilt virus (TSWV), the most prolific member of the group, was used to better understand the structure-function relationships of the nucleocapsid gene (N), and the silencing suppressor gene (NSs), coded by the TSWV small RNA. METHODS Using a global collection of orthotospoviral sequences, several amino acids that were conserved across the genus and the potential location of these conserved amino acid motifs in these proteins was determined. We used state of the art 3D modeling algorithms, MULTICOM-CLUSTER, MULTICOM-CONSTRUCT, MULTICOM-NOVEL, I-TASSER, ROSETTA and CONFOLD to predict the secondary and tertiary structures of the N and the NSs proteins. RESULTS We identified nine amino acid residues in the N protein among 31 known tospoviral species, and ten amino acid residues in NSs protein among 27 tospoviral species that were conserved across the genus. For the N protein, all three algorithms gave nearly identical tertiary models. While the conserved residues were distributed throughout the protein on a linear scale, at the tertiary level, three residues were consistently located in the coil in all the models. For NSs protein models, there was no agreement among the three algorithms. However, with respect to the localization of the conserved motifs, G18 was consistently located in coil, while H115 was localized in the coil in three models. CONCLUSIONS This is the first report of predicting the 3D structure of any tospoviral NSs protein and revealed a consistent location for two of the ten conserved residues. The modelers used gave accurate prediction for N protein allowing the localization of the conserved residues. Results form the basis for further work on the structure-function relationships of tospoviral proteins and could be useful in developing novel virus control strategies targeting the conserved residues.
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Affiliation(s)
- Cristian Olaya
- Department of Plant Pathology, Washington State University, Pullman, WA, 99164, USA
| | - Badri Adhikari
- Department of Mathematics and Computer Science, University of Missouri, St. Louis, MO, 63121, USA
| | - Gaurav Raikhy
- Department of Microbiology and Immunology, Louisiana State University, Shreverport, LA, 71101, USA
| | - Jianlin Cheng
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, 65211, USA
| | - Hanu R Pappu
- Department of Plant Pathology, Washington State University, Pullman, WA, 99164, USA.
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Assessment of data-assisted prediction by inclusion of crosslinking/mass-spectrometry and small angle X-ray scattering data in the 12thCritical Assessment of protein Structure Prediction experiment. Proteins 2017; 86 Suppl 1:215-227. [DOI: 10.1002/prot.25442] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/16/2017] [Accepted: 12/10/2017] [Indexed: 12/26/2022]
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8
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Cao R, Adhikari B, Bhattacharya D, Sun M, Hou J, Cheng J. QAcon: single model quality assessment using protein structural and contact information with machine learning techniques. Bioinformatics 2017; 33:586-588. [PMID: 28035027 DOI: 10.1093/bioinformatics/btw694] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 11/01/2016] [Indexed: 11/14/2022] Open
Abstract
Motivation Protein model quality assessment (QA) plays a very important role in protein structure prediction. It can be divided into two groups of methods: single model and consensus QA method. The consensus QA methods may fail when there is a large portion of low quality models in the model pool. Results In this paper, we develop a novel single-model quality assessment method QAcon utilizing structural features, physicochemical properties, and residue contact predictions. We apply residue-residue contact information predicted by two protein contact prediction methods PSICOV and DNcon to generate a new score as feature for quality assessment. This novel feature and other 11 features are used as input to train a two-layer neural network on CASP9 datasets to predict the quality of a single protein model. We blindly benchmarked our method QAcon on CASP11 dataset as the MULTICOM-CLUSTER server. Based on the evaluation, our method is ranked as one of the top single model QA methods. The good performance of the features based on contact prediction illustrates the value of using contact information in protein quality assessment. Availability and Implementation The web server and the source code of QAcon are freely available at: http://cactus.rnet.missouri.edu/QAcon. Contact chengji@missouri.edu. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Renzhi Cao
- Department of Computer Science, Pacific Lutheran University, WA 98447, USA
| | - Badri Adhikari
- Department of Computer Science, University of Missouri, Columbia, MO 65211, USA
| | - Debswapna Bhattacharya
- Department of Electrical Engineering and Computer Science, Wichita State University, Wichita, KS 67260-0083, USA
| | - Miao Sun
- Department of Electrical and Computer Engineering
| | - Jie Hou
- Department of Computer Science, University of Missouri, Columbia, MO 65211, USA
| | - Jianlin Cheng
- Department of Computer Science, University of Missouri, Columbia, MO 65211, USA.,Informatics Institute, University of Missouri, Columbia, MO 65211, USA
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Lam SD, Das S, Sillitoe I, Orengo C. An overview of comparative modelling and resources dedicated to large-scale modelling of genome sequences. Acta Crystallogr D Struct Biol 2017; 73:628-640. [PMID: 28777078 PMCID: PMC5571743 DOI: 10.1107/s2059798317008920] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 06/14/2017] [Indexed: 12/02/2022] Open
Abstract
Computational modelling of proteins has been a major catalyst in structural biology. Bioinformatics groups have exploited the repositories of known structures to predict high-quality structural models with high efficiency at low cost. This article provides an overview of comparative modelling, reviews recent developments and describes resources dedicated to large-scale comparative modelling of genome sequences. The value of subclustering protein domain superfamilies to guide the template-selection process is investigated. Some recent cases in which structural modelling has aided experimental work to determine very large macromolecular complexes are also cited.
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Affiliation(s)
- Su Datt Lam
- Institute of Structural and Molecular Biology, UCL, Darwin Building, Gower Street, London WC1E 6BT, England
- School of Biosciences and Biotechnology, Faculty of Science and Technology, University Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
| | - Sayoni Das
- Institute of Structural and Molecular Biology, UCL, Darwin Building, Gower Street, London WC1E 6BT, England
| | - Ian Sillitoe
- Institute of Structural and Molecular Biology, UCL, Darwin Building, Gower Street, London WC1E 6BT, England
| | - Christine Orengo
- Institute of Structural and Molecular Biology, UCL, Darwin Building, Gower Street, London WC1E 6BT, England
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10
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Olechnovič K, Venclovas Č. VoroMQA: Assessment of protein structure quality using interatomic contact areas. Proteins 2017; 85:1131-1145. [DOI: 10.1002/prot.25278] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 01/13/2017] [Accepted: 02/21/2017] [Indexed: 12/14/2022]
Affiliation(s)
- Kliment Olechnovič
- Institute of Biotechnology, Vilnius University; Saulėtekio 7 LT-10257 Vilnius Lithuania
- Faculty of Mathematics and Informatics; Vilnius University; Naugarduko 24 LT-03225 Vilnius Lithuania
| | - Česlovas Venclovas
- Institute of Biotechnology, Vilnius University; Saulėtekio 7 LT-10257 Vilnius Lithuania
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11
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Li H, Lyu Q, Cheng J. A Template-Based Protein Structure Reconstruction Method Using Deep Autoencoder Learning. ACTA ACUST UNITED AC 2016; 9:306-313. [PMID: 29081613 PMCID: PMC5658031 DOI: 10.4172/jpb.1000419] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Protein structure prediction is an important problem in computational biology, and is widely applied to various biomedical problems such as protein function study, protein design, and drug design. In this work, we developed a novel deep learning approach based on a deeply stacked denoising autoencoder for protein structure reconstruction. We applied our approach to a template-based protein structure prediction using only the 3D structural coordinates of homologous template proteins as input. The templates were identified for a target protein by a PSI-BLAST search. 3DRobot (a program that automatically generates diverse and well-packed protein structure decoys) was used to generate initial decoy models for the target from the templates. A stacked denoising autoencoder was trained on the decoys to obtain a deep learning model for the target protein. The trained deep model was then used to reconstruct the final structural model for the target sequence. With target proteins that have highly similar template proteins as benchmarks, the GDT-TS score of the predicted structures is greater than 0.7, suggesting that the deep autoencoder is a promising method for protein structure reconstruction.
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Affiliation(s)
- Haiou Li
- Department of Computer Science and Technology, Soochow University, Suzhou, 215006, China.,Department of Computer Science, University of Missouri, Columbia, MO 65211, USA
| | - Qiang Lyu
- Department of Computer Science and Technology, Soochow University, Suzhou, 215006, China
| | - Jianlin Cheng
- Department of Computer Science, University of Missouri, Columbia, MO 65211, USA
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12
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Cao R, Bhattacharya D, Hou J, Cheng J. DeepQA: improving the estimation of single protein model quality with deep belief networks. BMC Bioinformatics 2016; 17:495. [PMID: 27919220 PMCID: PMC5139030 DOI: 10.1186/s12859-016-1405-y] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 12/01/2016] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Protein quality assessment (QA) useful for ranking and selecting protein models has long been viewed as one of the major challenges for protein tertiary structure prediction. Especially, estimating the quality of a single protein model, which is important for selecting a few good models out of a large model pool consisting of mostly low-quality models, is still a largely unsolved problem. RESULTS We introduce a novel single-model quality assessment method DeepQA based on deep belief network that utilizes a number of selected features describing the quality of a model from different perspectives, such as energy, physio-chemical characteristics, and structural information. The deep belief network is trained on several large datasets consisting of models from the Critical Assessment of Protein Structure Prediction (CASP) experiments, several publicly available datasets, and models generated by our in-house ab initio method. Our experiments demonstrate that deep belief network has better performance compared to Support Vector Machines and Neural Networks on the protein model quality assessment problem, and our method DeepQA achieves the state-of-the-art performance on CASP11 dataset. It also outperformed two well-established methods in selecting good outlier models from a large set of models of mostly low quality generated by ab initio modeling methods. CONCLUSION DeepQA is a useful deep learning tool for protein single model quality assessment and protein structure prediction. The source code, executable, document and training/test datasets of DeepQA for Linux is freely available to non-commercial users at http://cactus.rnet.missouri.edu/DeepQA/ .
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Affiliation(s)
- Renzhi Cao
- Department of Computer Science, Pacific Lutheran University, Tacoma, WA, 98447, USA
| | - Debswapna Bhattacharya
- Department of Electrical Engineering and Computer Science, Wichita State University, Wichita, KS, 67260, USA
| | - Jie Hou
- Department of Computer Science, University of Missouri, Columbia, MO, 65211, USA
| | - Jianlin Cheng
- Department of Computer Science, University of Missouri, Columbia, MO, 65211, USA. .,Informatics Institute, University of Missouri, Columbia, MO, 65211, USA.
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13
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Li J, Cheng J. A Stochastic Point Cloud Sampling Method for Multi-Template Protein Comparative Modeling. Sci Rep 2016; 6:25687. [PMID: 27161489 PMCID: PMC4861977 DOI: 10.1038/srep25687] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 04/21/2016] [Indexed: 12/04/2022] Open
Abstract
Generating tertiary structural models for a target protein from the known structure of its homologous template proteins and their pairwise sequence alignment is a key step in protein comparative modeling. Here, we developed a new stochastic point cloud sampling method, called MTMG, for multi-template protein model generation. The method first superposes the backbones of template structures, and the Cα atoms of the superposed templates form a point cloud for each position of a target protein, which are represented by a three-dimensional multivariate normal distribution. MTMG stochastically resamples the positions for Cα atoms of the residues whose positions are uncertain from the distribution, and accepts or rejects new position according to a simulated annealing protocol, which effectively removes atomic clashes commonly encountered in multi-template comparative modeling. We benchmarked MTMG on 1,033 sequence alignments generated for CASP9, CASP10 and CASP11 targets, respectively. Using multiple templates with MTMG improves the GDT-TS score and TM-score of structural models by 2.96–6.37% and 2.42–5.19% on the three datasets over using single templates. MTMG’s performance was comparable to Modeller in terms of GDT-TS score, TM-score, and GDT-HA score, while the average RMSD was improved by a new sampling approach. The MTMG software is freely available at: http://sysbio.rnet.missouri.edu/multicom_toolbox/mtmg.html.
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Affiliation(s)
- Jilong Li
- Department of Computer Science, University of Missouri, Columbia, MO 65211, USA
| | - Jianlin Cheng
- Department of Computer Science, University of Missouri, Columbia, MO 65211, USA.,Informatics Institute, University of Missouri, Columbia, MO 65211, USA
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14
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Protein single-model quality assessment by feature-based probability density functions. Sci Rep 2016; 6:23990. [PMID: 27041353 PMCID: PMC4819172 DOI: 10.1038/srep23990] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 03/17/2016] [Indexed: 11/11/2022] Open
Abstract
Protein quality assessment (QA) has played an important role in protein structure prediction. We developed a novel single-model quality assessment method–Qprob. Qprob calculates the absolute error for each protein feature value against the true quality scores (i.e. GDT-TS scores) of protein structural models, and uses them to estimate its probability density distribution for quality assessment. Qprob has been blindly tested on the 11th Critical Assessment of Techniques for Protein Structure Prediction (CASP11) as MULTICOM-NOVEL server. The official CASP result shows that Qprob ranks as one of the top single-model QA methods. In addition, Qprob makes contributions to our protein tertiary structure predictor MULTICOM, which is officially ranked 3rd out of 143 predictors. The good performance shows that Qprob is good at assessing the quality of models of hard targets. These results demonstrate that this new probability density distribution based method is effective for protein single-model quality assessment and is useful for protein structure prediction. The webserver of Qprob is available at: http://calla.rnet.missouri.edu/qprob/. The software is now freely available in the web server of Qprob.
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