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1.
Anal Biochem ; 588: 113477, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31654612

RESUMO

Proteases are a type of enzymes, which perform the process of proteolysis. Proteolysis normally refers to protein and peptide degradation which is crucial for the survival, growth and wellbeing of a cell. Moreover, proteases have a strong association with therapeutics and drug development. The proteases are classified into five different types according to their nature and physiochemical characteristics. Mostly the methods used to differentiate protease from other proteins and identify their class requires a clinical test which is usually time-consuming and operator dependent. Herein, we report a classifier named iProtease-PseAAC (2L) for identifying proteases and their classes. The predictor is developed employing the flow of 5-step rule, initiating from the collection of benchmark dataset and terminating at the development of predictor. Rigorous verification and validation tests are performed and metrics are collected to calculate the authenticity of the trained model. The self-consistency validation gives the 98.32% accuracy, for cross-validation the accuracy is 90.71% and jackknife gives 96.07% accuracy. The average accuracy for level-2 i.e. protease classification is 95.77%. Based on the above-mentioned results, it is concluded that iProtease-PseAAC (2L) has the great ability to identify the proteases and their classes using a given protein sequence.


Assuntos
Algoritmos , Biologia Computacional/métodos , Peptídeo Hidrolases/classificação , Proteínas/classificação , Software , Bases de Dados de Proteínas
2.
Mol Genet Genomics ; 294(1): 199-210, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30291426

RESUMO

Nucleosome is a central element of eukaryotic chromatin, which composes of histone proteins and DNA molecules. It performs vital roles in many eukaryotic intra-nuclear processes, for instance, chromatin structure and transcriptional regulation formation. Identification of nucleosome positioning via wet lab is difficult; so, the attention is diverted towards the accurate intelligent automated prediction. In this regard, a novel intelligent automated model "iNuc-ext-PseTNC" is developed to identify the nucleosome positioning in genomes accurately. In this predictor, the sequences of DNA are mathematically represented by two different discrete feature extraction techniques, namely pseudo-tri-nucleotide composition (PseTNC) and pseudo-di-nucleotide composition. Several contemporary machine learning algorithms were examined. Further, the predictions of individual classifiers were integrated through an evolutionary genetic algorithm. The success rates of the ensemble model are higher than individual classifiers. After analyzing the prediction results, it is noticed that iNuc-ext-PseTNC model has achieved better performance in combination with PseTNC feature space, which are 94.3%, 93.14%, and 88.60% of accuracies using six-fold cross-validation test for the three benchmark datasets S1, S2, and S3, respectively. The achieved outcomes exposed that the results of iNuc-ext-PseTNC model are prominent compared to the existing methods so far notifiable in the literature. It is ascertained that the proposed model might be more fruitful and a practical tool for rudimentary academia and research.


Assuntos
Caenorhabditis elegans/genética , Biologia Computacional/métodos , Drosophila melanogaster/genética , Nucleossomos/genética , Algoritmos , Animais , Composição de Bases , Humanos , Máquina de Vetores de Suporte
3.
Anal Biochem ; 568: 14-23, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30593778

RESUMO

S-Palmitoylation is a uniquely reversible and biologically important post-translational modification as it plays an essential role in a variety of cellular processes including signal transduction, protein-membrane interactions, neuronal development, lipid raft targeting, subcellular localization and apoptosis. Due to its association with the neuronal development, it plays a pivotal role in a variety of neurodegenerative diseases, mainly Alzheimer's, Schizophrenia and Huntington's disease. It is also essential for developmental life cycles and pathogenesis of Toxoplasma gondii and Plasmodium falciparum, known to cause toxoplasmosis and malaria, respectively. This depicts the strong biological significance of S-Palmitoylation, thus, the timely and accurate identification of S-palmitoylation sites is crucial. Herein, we propose a predictor for S-Palmitoylation sites in proteins namely SPalmitoylC-PseAAC by integrating the Chou's Pseudo Amino Acid Composition (PseAAC) and relative/absolute position-based features. Self-consistency testing and 10-fold cross-validation are performed to evaluate the performance of SPalmitoylC-PseAAC, using accuracy metrics. For self-consistency testing, 99.79% Acc, 99.77% Sp, 99.80% Sn and 1.00 MCC was observed, whereas, for 10-fold cross validation 97.22% Acc, 98.85% Sp, 95.80% Sn and 0.94 MCC was observed. Thus the proposed predictor can help in predicting the palmitoylation sites in an efficient and accurate way. The SPalmitoylC-PseAAC is available at (biopred.org/palm).


Assuntos
Proteínas de Membrana/metabolismo , Modelos Biológicos , Aciltransferases/química , Aciltransferases/metabolismo , Aminoácidos/química , Aminoácidos/metabolismo , Sequência de Bases , Bases de Dados de Proteínas , Humanos , Proteínas de Membrana/química , Ácido Palmítico/química , Ácido Palmítico/metabolismo , Processamento de Proteína Pós-Traducional
4.
J Theor Biol ; 468: 1-11, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30768975

RESUMO

The protein prenylation (or S-prenylation) is one of the most essential modifications, required for the association of membrane of a plethora of signalling proteins with the key biological process such as protein trafficking, cell growth, proliferation and differentiation. Due to the ubiquitous nature of S-prenylation and its role in cellular functions, any defect in the biosynthesis or regulation of the isoprenoid leads to the occurrence of a variety of diseases including neurodegenerative disorders, metabolic issues, cardiovascular diseases and one of the most fatal diseases, cancer. This depicts the strong biological significance of S-prenylation, thus, the timely and accurate identification of S-prenylation sites is crucial and may provide with possible ways to understand the mechanism of this modification in proteins. To avoid laborious, resource demanding and expensive experimental techniques of identifying S-prenylation sites, here, we propose a novel predictor namely SPrenylC-PseAAC by integrating the Chou's Pseudo Amino Acid Composition (PseAAC) and relative/absolute position-based features. A 2-tier classification was performed i.e., at first level, identification of prenylation and non-prenylation sites is performed, while at the second level, identification of S-farnesylation and S-geranylgeranylation sites is performed. Using jackknife, perdition model validation gave 95.31% accuracy for tier-1 classification and 91.42% for tier 2 classification, while for 10-fold cross-validation, it gave 93.68% accuracy for tier-1 classification and 89.70% for tier 2 classification. Thus the proposed predictor can help in predicting the Prenylation sites in an efficient and accurate way. The SPrenylC-PseAAC is available at (biopred.org/prenyl).


Assuntos
Algoritmos , Aminoácidos/química , Modelos Moleculares , Prenilação de Proteína , Sequência de Aminoácidos , Internet , Redes Neurais de Computação , Fosfatos de Poli-Isoprenil/química , Curva ROC , Reprodutibilidade dos Testes , Sesquiterpenos/química , Interface Usuário-Computador
5.
J Theor Biol ; 463: 47-55, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30550863

RESUMO

The structure of protein gains additional stability against various detrimental effects by the presence of disulfide bonds. The formation of correct disulfide bonds between cysteine residues ensures proper in vivo and in vitro folding of the protein. Many cysteine residues can be present in the polypeptide chain of a protein, however, not all cysteine residues are involved in the formation of a disulfide bond, and therefore, accurate prediction of these bonds is crucial for identifying biophysical characteristics of a protein. In the present study, a novel method is proposed for the prediction of intramolecular disulfide bonds accurately using statistical moments and PseAAC. The pSSbond-PseAAC uses PseAAC along with position and composition relative features to calculate statistical moments. Statistical moments are important as they are very sensitive regarding the position of data sequences and for prediction of intramolecular disulfide bonds, moments are combined together to train neural networks. The overall accuracy of the pSSbond-PseAAC is 98.97% to sensitivity value 98.92%, specificity 98.99% and 0.98 MCC; and it outperforms various previously reported studies.


Assuntos
Cisteína/metabolismo , Dissulfetos/química , Proteínas/química , Biologia Computacional/métodos , Redes Neurais de Computação , Aprendizado de Máquina Supervisionado
6.
Curr Genomics ; 20(4): 306-320, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-32030089

RESUMO

BACKGROUND: The amino acid residues, in protein, undergo post-translation modification (PTM) during protein synthesis, a process of chemical and physical change in an amino acid that in turn alters behavioral properties of proteins. Tyrosine sulfation is a ubiquitous posttranslational modification which is known to be associated with regulation of various biological functions and pathological pro-cesses. Thus its identification is necessary to understand its mechanism. Experimental determination through site-directed mutagenesis and high throughput mass spectrometry is a costly and time taking process, thus, the reliable computational model is required for identification of sulfotyrosine sites. METHODOLOGY: In this paper, we present a computational model for the prediction of the sulfotyrosine sites named iSulfoTyr-PseAAC in which feature vectors are constructed using statistical moments of protein amino acid sequences and various position/composition relative features. These features are in-corporated into PseAAC. The model is validated by jackknife, cross-validation, self-consistency and in-dependent testing. RESULTS: Accuracy determined through validation was 93.93% for jackknife test, 95.16% for cross-validation, 94.3% for self-consistency and 94.3% for independent testing. CONCLUSION: The proposed model has better performance as compared to the existing predictors, how-ever, the accuracy can be improved further, in future, due to increasing number of sulfotyrosine sites in proteins.

7.
Curr Genomics ; 20(4): 275-292, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-32030087

RESUMO

BACKGROUND: Methylation is one of the most important post-translational modifications in the human body which usually arises on lysine among the most intensely modified residues. It performs a dynamic role in numerous biological procedures, such as regulation of gene expression, regulation of protein function and RNA processing. Therefore, to identify lysine methylation sites is an important challenge as some experimental procedures are time-consuming. OBJECTIVE: Herein, we propose a computational predictor named iMethylK_pseAAC to identify lysine methylation sites. METHODS: Firstly, we constructed feature vectors based on PseAAC using position and composition rel-ative features and statistical moments. A neural network is trained based on the extracted features. The performance of the proposed method is then validated using cross-validation and jackknife testing. RESULTS: The objective evaluation of the predictor showed accuracy of 96.7% for self-consistency, 91.61% for 10-fold cross-validation and 93.42% for jackknife testing. CONCLUSION: It is concluded that iMethylK_pseAAC outperforms the counterparts to identify lysine methylation sites such as iMethyl_pseACC, BPB_pPMS and PMeS.

8.
Anal Biochem ; 550: 109-116, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29704476

RESUMO

Among all the post-translational modifications (PTMs) of proteins, Phosphorylation is known to be the most important and highly occurring PTM in eukaryotes and prokaryotes. It has an important regulatory mechanism which is required in most of the pathological and physiological processes including neural activity and cell signalling transduction. The process of threonine phosphorylation modifies the threonine by the addition of a phosphoryl group to the polar side chain, and generates phosphothreonine sites. The investigation and prediction of phosphorylation sites is important and various methods have been developed based on high throughput mass-spectrometry but such experimentations are time consuming and laborious therefore, an efficient and accurate novel method is proposed in this study for the prediction of phosphothreonine sites. The proposed method uses context-based data to calculate statistical moments. Position relative statistical moments are combined together to train neural networks. Using 10-fold cross validation, 94.97% accurate result has been obtained whereas for Jackknife testing, 96% accurate results have been obtained. The overall accuracy of the system is 94.4% to sensitivity value 94% and specificity 94.6%. These results suggest that the proposed method may play an essential role to the other existing methods for phosphothreonine sites prediction.


Assuntos
Fosfoproteínas , Fosfotreonina/química , Análise de Sequência de Proteína/métodos , Software , Fosfoproteínas/química , Fosfoproteínas/genética , Fosforilação
9.
Mol Biol Rep ; 45(6): 2501-2509, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30311130

RESUMO

Protein phosphorylation is one of the most fundamental types of post-translational modifications and it plays a vital role in various cellular processes of eukaryotes. Among three types of phosphorylation i.e. serine, threonine and tyrosine phosphorylation, tyrosine phosphorylation is one of the most frequent and it is important for mediation of signal transduction in eukaryotic cells. Site-directed mutagenesis and mass spectrometry help in the experimental determination of cellular signalling networks, however, these techniques are costly, time taking and labour associated. Thus, efficient and accurate prediction of these sites through computational approaches can be beneficial to reduce cost and time. Here, we present a more accurate and efficient sequence-based computational method for prediction of phosphotyrosine (PhosY) sites by incorporation of statistical moments into PseAAC. The study is carried out based on Chou's 5-step rule, and various position-composition relative features are used to train a neural network for the prediction purpose. Validation of results through Jackknife testing is performed to validate the results of the proposed prediction method. Overall accuracy validated through Jackknife testing was calculated 93.9%. These results suggest that the proposed prediction model can play a fundamental role in the prediction of PhosY sites in an accurate and efficient way.


Assuntos
Biologia Computacional/métodos , Previsões/métodos , Análise de Sequência de DNA/métodos , Algoritmos , Aminoácidos , Biometria , Bases de Dados de Proteínas , Fosforilação/genética , Fosfotirosina/genética , Fosfotirosina/metabolismo , Processamento de Proteína Pós-Traducional
10.
J Theor Biol ; 415: 13-19, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-27939596

RESUMO

This study investigates an efficient and accurate computational method for predicating mycobacterial membrane protein. Mycobacterium is a pathogenic bacterium which is the causative agent of tuberculosis and leprosy. The existing feature encoding algorithms for protein sequence representation such as composition and translation, and split amino acid composition cannot suitably express the mycobacterium membrane protein and their types due to biasness among different types. Therefore, in this study a novel un-biased dipeptide composition (Unb-DPC) method is proposed. The proposed encoding scheme has two advantages, first it avoid the biasness among the different mycobacterium membrane protein and their types. Secondly, the method is fast and preserves protein sequence structure information. The experimental results yield SVM based classification accurately of 97.1% for membrane protein types and 95.0% for discriminating mycobacterium membrane and non-membrane proteins by using jackknife cross validation test. The results exhibit that proposed model achieved significant predictive performance compared to the existing algorithms and will lead to develop a powerful tool for anti-mycobacterium drugs.


Assuntos
Dipeptídeos/química , Proteínas de Membrana/química , Modelos Teóricos , Mycobacteriaceae/química , Algoritmos , Sequência de Aminoácidos , Viés , Biologia Computacional/métodos , Proteínas de Membrana/classificação , Mycobacteriaceae/ultraestrutura
11.
J Theor Biol ; 435: 116-124, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-28927812

RESUMO

Mycobacterium is a pathogenic bacterium, which is a causative agent of tuberculosis (TB) and leprosy. These diseases are very crucial and become the cause of death of millions of people every year in the world. So, the characterize structure of membrane proteins of the protozoan play a vital role in the field of drug discovery because, without any knowledge about this Mycobacterium's membrane protein and their types, the scientists are unable to treat this pathogenic protozoan. So, an accurate and competitive computational model is needed to characterize this uncharacterized structure of mycobacterium. Series of attempts were carried out in this connection. Split amino acid compositions, Unbiased-Dipeptide peptide compositions (Unb-DPC), Over-represented tri-peptide compositions, compositions & translation were the few recent encoding techniques followed by different researchers in their publications. Although considerable results have been achieved by these models, still there is a gap which is filled in this study. In this study, an evolutionary feature extraction technique position specific scoring matrix (PSSM) is applied in order to extract evolutionary information from protein sequences. Consequently, 99.6% accuracy was achieved by the learning algorithms. The experimental results demonstrated that the proposed computational model will lead to develop a powerful tool for anti-mycobacterium drugs as well as play a promising rule in proteomic and bioinformatics.


Assuntos
Inteligência Artificial , Proteínas de Bactérias/análise , Proteínas de Membrana/análise , Mycobacterium/química , Matrizes de Pontuação de Posição Específica , Sequência de Aminoácidos , Biologia Computacional/métodos , Evolução Molecular
12.
ScientificWorldJournal ; 2015: 579390, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25945363

RESUMO

Software birthmark is a unique quality of software to detect software theft. Comparing birthmarks of software can tell us whether a program or software is a copy of another. Software theft and piracy are rapidly increasing problems of copying, stealing, and misusing the software without proper permission, as mentioned in the desired license agreement. The estimation of birthmark can play a key role in understanding the effectiveness of a birthmark. In this paper, a new technique is presented to evaluate and estimate software birthmark based on the two most sought-after properties of birthmarks, that is, credibility and resilience. For this purpose, the concept of soft computing such as probabilistic and fuzzy computing has been taken into account and fuzzy logic is used to estimate properties of birthmark. The proposed fuzzy rule based technique is validated through a case study and the results show that the technique is successful in assessing the specified properties of the birthmark, its resilience and credibility. This, in turn, shows how much effort will be required to detect the originality of the software based on its birthmark.

13.
J Theor Biol ; 346: 8-15, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24384128

RESUMO

Proteins are the executants of biological functions in living organisms. Comprehension of protein structure is a challenging problem in the era of proteomics, computational biology, and bioinformatics because of its pivotal role in protein folding patterns. Owing to the large exploration of protein sequences in protein databanks and intricacy of protein structures, experimental and theoretical methods are insufficient for prediction of protein structure classes. Therefore, it is highly desirable to develop an accurate, reliable, and high throughput computational model to predict protein structure classes correctly from polygenetic sequences. In this regard, we propose a promising model employing hybrid descriptor space in conjunction with optimized evidence-theoretic K-nearest neighbor algorithm. Hybrid space is the composition of two descriptor spaces including Multi-profile Bayes and bi-gram probability. In order to enhance the generalization power of the classifier, we have selected high discriminative descriptors from the hybrid space using particle swarm optimization, a well-known evolutionary feature selection technique. Performance evaluation of the proposed model is performed using the jackknife test on three low similarity benchmark datasets including 25PDB, 1189, and 640. The success rates of the proposed model are 87.0%, 86.6%, and 88.4%, respectively on the three benchmark datasets. The comparative analysis exhibits that our proposed model has yielded promising results compared to the existing methods in the literature. In addition, our proposed prediction system might be helpful in future research particularly in cases where the major focus of research is on low similarity datasets.


Assuntos
Algoritmos , Probabilidade , Proteínas/química , Sequência de Aminoácidos , Teorema de Bayes , Bases de Dados de Proteínas , Modelos Moleculares , Dados de Sequência Molecular
14.
ScientificWorldJournal ; 2014: 723595, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24977221

RESUMO

This paper presents a biometric technique for identification of a person using the iris image. The iris is first segmented from the acquired image of an eye using an edge detection algorithm. The disk shaped area of the iris is transformed into a rectangular form. Described moments are extracted from the grayscale image which yields a feature vector containing scale, rotation, and translation invariant moments. Images are clustered using the k-means algorithm and centroids for each cluster are computed. An arbitrary image is assumed to belong to the cluster whose centroid is the nearest to the feature vector in terms of Euclidean distance computed. The described model exhibits an accuracy of 98.5%.


Assuntos
Algoritmos , Inteligência Artificial , Biometria/métodos , Interpretação de Imagem Assistida por Computador/métodos , Iris/anatomia & histologia , Reconhecimento Automatizado de Padrão/métodos , Humanos , Aumento da Imagem/métodos
15.
ScientificWorldJournal ; 2014: 875879, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25250389

RESUMO

Recognition of human actions is an emerging need. Various researchers have endeavored to provide a solution to this problem. Some of the current state-of-the-art solutions are either inaccurate or computationally intensive while others require human intervention. In this paper a sufficiently accurate while computationally inexpensive solution is provided for the same problem. Image moments which are translation, rotation, and scale invariant are computed for a frame. A dynamic neural network is used to identify the patterns within the stream of image moments and hence recognize actions. Experiments show that the proposed model performs better than other competitive models.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Movimento , Redes Neurais de Computação , Humanos , Interpretação de Imagem Assistida por Computador/normas , Reconhecimento Automatizado de Padrão/métodos , Reconhecimento Automatizado de Padrão/normas , Análise de Componente Principal
16.
Appl Bionics Biomech ; 2022: 5483115, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465187

RESUMO

In the domain of genome annotation, the identification of DNA-binding protein is one of the crucial challenges. DNA is considered a blueprint for the cell. It contained all necessary information for building and maintaining the trait of an organism. It is DNA, which makes a living thing, a living thing. Protein interaction with DNA performs an essential role in regulating DNA functions such as DNA repair, transcription, and regulation. Identification of these proteins is a crucial task for understanding the regulation of genes. Several methods have been developed to identify the binding sites of DNA and protein depending upon the structures and sequences, but they were costly and time-consuming. Therefore, we propose a methodology named "DNAPred_Prot", which uses various position and frequency-dependent features from protein sequences for efficient and effective prediction of DNA-binding proteins. Using testing techniques like 10-fold cross-validation and jackknife testing an accuracy of 94.95% and 95.11% was yielded, respectively. The results of SVM and ANN were also compared with those of a random forest classifier. The robustness of the proposed model was evaluated by using the independent dataset PDB186, and an accuracy of 91.47% was achieved by it. From these results, it can be predicted that the suggested methodology performs better than other extant methods for the identification of DNA-binding proteins.

17.
Membranes (Basel) ; 12(3)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35323738

RESUMO

Acetylation is the most important post-translation modification (PTM) in eukaryotes; it has manifold effects on the level of protein that transform an acetyl group from an acetyl coenzyme to a specific site on a polypeptide chain. Acetylation sites play many important roles, including regulating membrane protein functions and strongly affecting the membrane interaction of proteins and membrane remodeling. Because of these properties, its correct identification is essential to understand its mechanism in biological systems. As such, some traditional methods, such as mass spectrometry and site-directed mutagenesis, are used, but they are tedious and time-consuming. To overcome such limitations, many computer models are being developed to correctly identify their sequences from non-acetyl sequences, but they have poor efficiency in terms of accuracy, sensitivity, and specificity. This work proposes an efficient and accurate computational model for predicting Acetylation using machine learning approaches. The proposed model achieved an accuracy of 100 percent with the 10-fold cross-validation test based on the Random Forest classifier, along with a feature extraction approach using statistical moments. The model is also validated by the jackknife, self-consistency, and independent test, which achieved an accuracy of 100, 100, and 97, respectively, results far better as compared to the already existing models available in the literature.

18.
Mol Biol Rep ; 38(5): 3227-33, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20213504

RESUMO

We studied heterologous expression of xylanase 11A gene of Chaetomium thermophilum in Pichia pastoris and characterized the thermostable nature of the purified gene product. For this purpose, the xylanase 11A gene of C. thermophilum was cloned in P. pastoris GS115 under the control of AOX1 promoter. The maximum extracellular activity of recombinant xylanase (xyn698: gene with intron) was 15.6 U ml(-1) while that of recombinant without intron (xyn669) was 1.26 U ml(-1) after 96 h growth. The gene product was purified apparently to homogeneity level. The optimum temperature of pure recombinant xylanase activity was 70°C and the enzyme retained its 40.57% activity after incubation at 80°C for 10 min. It exhibited quite lower demand of activation energy, enthalpy, Gibbs free energy, entropy, and xylan binding energy during substrate hydrolysis than that required by that of the donor, thus indicating its thermostable nature. pH-dependent catalysis showed that it was quite stable in a pH range of 5.5-8.5. This revealed that gene was successfully processed in P. pastoris and remained heat stable and may qualify for its potential use in paper and pulp and animal feed applications.


Assuntos
Chaetomium/enzimologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pichia/metabolismo , Xilano Endo-1,3-beta-Xilosidase/genética , Xilano Endo-1,3-beta-Xilosidase/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Estabilidade Enzimática , Dados de Sequência Molecular , Pichia/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Termodinâmica
19.
Biotechnol Lett ; 33(7): 1457-63, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21369907

RESUMO

Spider venoms are neurotoxin proteins that can kill insects. Spider toxin Hvt gene was cloned under two phloem specific RSs1 and RolC promoters, transformed into tobacco plants through Agrobacterium-mediated transformation and tested against Heliothis armigera larvae. Transgenic plants were confirmed through PCR. First instar larvae of H. armigera were released on detached leaves of transformed and non-transformed plants. Insect bioassays showed 93-100% mortality of H. armigera larvae within 72 h on the leaves of transgenic plants while all larvae survived and continued feeding on detached leaves from non-transformed control plants. The Hvt gene expressing under phloem specific RSs1 and RolC promoters could therefore be used for developing H. armigera-resistant, genetically-modified crops.


Assuntos
Expressão Gênica , Inseticidas/metabolismo , Lepidópteros/crescimento & desenvolvimento , Nicotiana/parasitologia , Plantas Geneticamente Modificadas/parasitologia , Venenos de Aranha/biossíntese , Animais , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Lepidópteros/efeitos dos fármacos , Regiões Promotoras Genéticas , Venenos de Aranha/genética , Análise de Sobrevida
20.
J Bioinform Comput Biol ; 19(4): 2150018, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34291709

RESUMO

DNA-binding proteins (DBPs) perform an influential role in diverse biological activities like DNA replication, slicing, repair, and transcription. Some DBPs are indispensable for understanding many types of human cancers (i.e. lung, breast, and liver cancer) and chronic diseases (i.e. AIDS/HIV, asthma), while other kinds are involved in antibiotics, steroids, and anti-inflammatory drugs designing. These crucial processes are closely related to DBPs types. DBPs are categorized into single-stranded DNA-binding proteins (ssDBPs) and double-stranded DNA-binding proteins (dsDBPs). Few computational predictors have been reported for discriminating ssDBPs and dsDBPs. However, due to the limitations of the existing methods, an intelligent computational system is still highly desirable. In this work, features from protein sequences are discovered by extending the notion of dipeptide composition (DPC), evolutionary difference formula (EDF), and K-separated bigram (KSB) into the position-specific scoring matrix (PSSM). The highly intrinsic information was encoded by a compression approach named discrete cosine transform (DCT) and the model was trained with support vector machine (SVM). The prediction performance was further boosted by the genetic algorithm (GA) ensemble strategy. The novel predictor (DBP-GAPred) acquired 1.89%, 0.28%, and 6.63% higher accuracies on jackknife, 10-fold, and independent dataset tests, respectively than the best predictor. These outcomes confirm the superiority of our method over the existing predictors.


Assuntos
Proteínas de Ligação a DNA , Máquina de Vetores de Suporte , Algoritmos , Sequência de Aminoácidos , Biologia Computacional , Proteínas de Ligação a DNA/genética , Bases de Dados de Proteínas , Humanos , Matrizes de Pontuação de Posição Específica
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