Displaying publications 1 - 20 of 233 in total

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  1. SPlitSSI-SVM: an algorithm to reduce the misleading and increase the strength of domain signal
    Kalsum HU, Shah ZA, Othman RM, Hassan R, Rahim SM, Asmuni H, et al.
    Comput Biol Med, 2009 Nov;39(11):1013-9.
    PMID: 19720371 DOI: 10.1016/j.compbiomed.2009.08.002
    Protein domains contain information about the prediction of protein structure, function, evolution and design since the protein sequence may contain several domains with different or the same copies of the protein domain. In this study, we proposed an algorithm named SplitSSI-SVM that works with the following steps. First, the training and testing datasets are generated to test the SplitSSI-SVM. Second, the protein sequence is split into subsequence based on order and disorder regions. The protein sequence that is more than 600 residues is split into subsequences to investigate the effectiveness of the protein domain prediction based on subsequence. Third, multiple sequence alignment is performed to predict the secondary structure using bidirectional recurrent neural networks (BRNN) where BRNN considers the interaction between amino acids. The information of about protein secondary structure is used to increase the protein domain boundaries signal. Lastly, support vector machines (SVM) are used to classify the protein domain into single-domain, two-domain and multiple-domain. The SplitSSI-SVM is developed to reduce misleading signal, lower protein domain signal caused by primary structure of protein sequence and to provide accurate classification of the protein domain. The performance of SplitSSI-SVM is evaluated using sensitivity and specificity on single-domain, two-domain and multiple-domain. The evaluation shows that the SplitSSI-SVM achieved better results compared with other protein domain predictors such as DOMpro, GlobPlot, Dompred-DPS, Mateo, Biozon, Armadillo, KemaDom, SBASE, HMMPfam and HMMSMART especially in two-domain and multiple-domain.
    Matched MeSH terms: Sequence Alignment
  2. Fulltext An Improved Strategy for Task Scheduling in the Parallel Computational Alignment of Multiple Sequences
    Ishaq M, Khan A, Su'ud MM, Alam MM, Bangash JI, Khan A
    Comput Math Methods Med, 2022;2022:8691646.
    PMID: 35126641 DOI: 10.1155/2022/8691646
    Task scheduling in parallel multiple sequence alignment (MSA) through improved dynamic programming optimization speeds up alignment processing. The increased importance of multiple matching sequences also needs the utilization of parallel processor systems. This dynamic algorithm proposes improved task scheduling in case of parallel MSA. Specifically, the alignment of several tertiary structured proteins is computationally complex than simple word-based MSA. Parallel task processing is computationally more efficient for protein-structured based superposition. The basic condition for the application of dynamic programming is also fulfilled, because the task scheduling problem has multiple possible solutions or options. Search space reduction for speedy processing of this algorithm is carried out through greedy strategy. Performance in terms of better results is ensured through computationally expensive recursive and iterative greedy approaches. Any optimal scheduling schemes show better performance in heterogeneous resources using CPU or GPU.
    Matched MeSH terms: Sequence Alignment/methods*; Sequence Alignment/statistics & numerical data
  3. Hungarian layer: A novel interpretable neural layer for paraphrase identification
    Xiao H
    Neural Netw, 2020 Nov;131:172-184.
    PMID: 32801109 DOI: 10.1016/j.neunet.2020.07.024
    Paraphrase identification serves as an important topic in natural language processing while sequence alignment and matching underlie the principle of this task. Traditional alignment methods take advantage of attention mechanism. Attention mechanism, i.e. weighting technique, could pick out the most similar/dissimilar parts, but is weak in modeling the aligned unmatched parts, which are the crucial evidence to identify paraphrases. In this paper, we empower neural architecture with Hungarian algorithm to extract the aligned unmatched parts. Specifically, first, our model applies BiLSTM/BERT to encode the input sentences into hidden representations. Then, Hungarian layer leverages the hidden representations to extract the aligned unmatched parts. Last, we apply cosine similarity to metric the aligned unmatched parts for a final discrimination. Extensive experiments show that our model outperforms other baselines, substantially and significantly.
    Matched MeSH terms: Sequence Alignment
  4. Fulltext Design pattern mining using distributed learning automata and DNA sequence alignment
    Esmaeilpour M, Naderifar V, Shukur Z
    PLoS One, 2014;9(9):e106313.
    PMID: 25243670 DOI: 10.1371/journal.pone.0106313
    Over the last decade, design patterns have been used extensively to generate reusable solutions to frequently encountered problems in software engineering and object oriented programming. A design pattern is a repeatable software design solution that provides a template for solving various instances of a general problem.
    Matched MeSH terms: Sequence Alignment*
  5. Samira-VP: A simple protein alignment method with rechecking the alphabet vector positions
    Fotoohifiroozabadi S, Mohamad MS, Deris S
    J Bioinform Comput Biol, 2017 Apr;15(2):1750004.
    PMID: 28274174 DOI: 10.1142/S0219720017500044
    Protein structure alignment and comparisons that are based on an alphabetical demonstration of protein structure are more simple to run with faster evaluation processes; thus, their accuracy is not as reliable as three-dimension (3D)-based tools. As a 1D method candidate, TS-AMIR used the alphabetic demonstration of secondary-structure elements (SSE) of proteins and compared the assigned letters to each SSE using the [Formula: see text]-gram method. Although the results were comparable to those obtained via geometrical methods, the SSE length and accuracy of adjacency between SSEs were not considered in the comparison process. Therefore, to obtain further information on accuracy of adjacency between SSE vectors, the new approach of assigning text to vectors was adopted according to the spherical coordinate system in the present study. Moreover, dynamic programming was applied in order to account for the length of SSE vectors. Five common datasets were selected for method evaluation. The first three datasets were small, but difficult to align, and the remaining two datasets were used to compare the capability of the proposed method with that of other methods on a large protein dataset. The results showed that the proposed method, as a text-based alignment approach, obtained results comparable to both 1D and 3D methods. It outperformed 1D methods in terms of accuracy and 3D methods in terms of runtime.
    Matched MeSH terms: Sequence Alignment/methods
  6. Fulltext Complete genome sequencing of Pandoraea pnomenusa RB38 and Molecular Characterization of Its N-acyl homoserine lactone synthase gene ppnI
    Lim YL, Ee R, How KY, Lee SK, Yong D, Tee KK, et al.
    PeerJ, 2015;3:e1225.
    PMID: 26336650 DOI: 10.7717/peerj.1225
    In this study, we sequenced the genome of Pandoraea pnomenusa RB38 using Pacific Biosciences RSII (PacBio) Single Molecule Real Time (SMRT) sequencing technology. A pair of cognate luxI/R homologs was identified where the luxI homolog, ppnI, was found adjacent to a luxR homolog, ppnR1. An additional orphan luxR homolog, ppnR2, was also discovered. Multiple sequence alignment and phylogenetic analysis revealed that ppnI is an N-acyl homoserine lactone (AHL) synthase gene that is distinct from those of the nearest phylogenetic neighbor viz. Burkholderia spp. High resolution tandem mass spectrometry (LC-MS/MS) analysis showed that Escherichia coli BL21 harboring ppnI produced a similar AHL profile (N-octanoylhomoserine lactone, C8-HSL) as P. pnomenusa RB38, the wild-type donor strain, confirming that PpnI directed the synthesis of AHL in P. pnomenusa RB38. To our knowledge, this is the first documentation of the luxI/R homologs of the genus Pandoraea.
    Matched MeSH terms: Sequence Alignment
  7. Fulltext Cloning and expression of a subfamily 1.4 lipase from Bacillus licheniformis IBRL-CHS2
    Reddy, Nidyaletchmy Subba, Rashidah Abdul Rahim, Darah Ibrahim, Kumar, K. Sudesh
    Trop Life Sci Res, 2016;27(11):145-150.
    MyJurnal
    We report on the cloning of the lipase gene from Bacillus licheniformis IBRLCHS2
    and the expression of the recombinant lipase. DNA sequencing analysis of the
    cloned lipase gene showed that it shares 99% identity with the lipase gene from
    B. licheniformis ATCC 14580 and belongs to subfamily 1.4 of true lipases based on amino
    acid sequence alignment of various Bacillus lipases. The 612 bp lipase gene was then
    cloned into the pET-15b(+) expression vector and the construct was transformed into
    E. coli BL21 (DE3) for bulk expression of the lipase. Expression was analysed by SDSPAGE
    where the lipase was found to have a molecular weight of about 23 kDa.
    Matched MeSH terms: Sequence Alignment
  8. Fulltext Draft Genomes of Anopheles cracens and Anopheles maculatus: Comparison of Simian Malaria and Human Malaria Vectors in Peninsular Malaysia
    Lau YL, Lee WC, Chen J, Zhong Z, Jian J, Amir A, et al.
    PLoS One, 2016;11(6):e0157893.
    PMID: 27347683 DOI: 10.1371/journal.pone.0157893
    Anopheles cracens has been incriminated as the vector of human knowlesi malaria in peninsular Malaysia. Besides, it is a good laboratory vector of Plasmodium falciparum and P. vivax. The distribution of An. cracens overlaps with that of An. maculatus, the human malaria vector in peninsular Malaysia that seems to be refractory to P. knowlesi infection in natural settings. Whole genome sequencing was performed on An. cracens and An. maculatus collected here. The draft genome of An. cracens was 395 Mb in size whereas the size of An. maculatus draft genome was 499 Mb. Comparison with the published Malaysian An. maculatus genome suggested the An. maculatus specimen used in this study as a different geographical race. Comparative analyses highlighted the similarities and differences between An. cracens and An. maculatus, providing new insights into their biological behavior and characteristics.
    Matched MeSH terms: Sequence Alignment
  9. Fulltext Data set of phylogenetic analysis inferred based on the complete genomes of the family Nodaviridae
    Low CF, Bunawan H
    Data Brief, 2016 Sep;8:1454-61.
    PMID: 27617282 DOI: 10.1016/j.dib.2016.08.025
    In this article, nine complete genomes of viruses from the genus Alphanodavirus and Betanodavirus (Family Nodaviridae) were comparatively analyzed and the data of their evolutionary origins and relatedness are reported. The nucleotide sequence alignment of the complete genomes from all species and their deduced evolutionary relationships are presented. High sequence similarity within the genus Betanodavirus compared to the genus Alphanodavirus was revealed in multiple sequence alignment of the Nodaviridae genomes. The amino acid sequence similarity for both RNA1 and RNA2 ORF is more conserved in Betanodavirus, compared to Alphanodavirus. The conserved and variable regions within the virus genome that were defined based on the multiple sequence alignments are presented in this dataset.
    Matched MeSH terms: Sequence Alignment
  10. Analysis of core protein clusters identifies candidate variable sites conferring metronidazole resistance in Helicobacter pylori
    Chua EG, Debowski AW, Webberley KM, Peters F, Lamichhane B, Loke MF, et al.
    Gastroenterol Rep (Oxf), 2019 Feb;7(1):42-49.
    PMID: 30792865 DOI: 10.1093/gastro/goy048
    Background: Metronidazole is one of the first-line drugs of choice in the standard triple therapy used to eradicate Helicobacter pylori infection. Hence, the global emergence of metronidazole resistance in Hp poses a major challenge to health professionals. Inactivation of RdxA is known to be a major mechanism of conferring metronidazole resistance in H. pylori. However, metronidazole resistance can also arise in H. pylori strains expressing functional RdxA protein, suggesting that there are other mechanisms that may confer resistance to this drug.

    Methods: We performed whole-genome sequencing on 121 H. pylori clinical strains, among which 73 were metronidazole-resistant. Sequence-alignment analysis of core protein clusters derived from clinical strains containing full-length RdxA was performed. Variable sites in each alignment were statistically compared between the resistant and susceptible groups to determine candidate genes along with their respective amino-acid changes that may account for the development of metronidazole resistance in H. pylori.

    Results: Resistance due to RdxA truncation was identified in 34% of metronidazole-resistant strains. Analysis of core protein clusters derived from the remaining 48 metronidazole-resistant strains and 48 metronidazole-susceptible identified four variable sites significantly associated with metronidazole resistance. These sites included R16H/C in RdxA, D85N in the inner-membrane protein RclC (HP0565), V265I in a biotin carboxylase protein (HP0370) and A51V/T in a putative threonylcarbamoyl-AMP synthase (HP0918).

    Conclusions: Our approach identified new potential mechanisms for metronidazole resistance in H. pylori that merit further investigation.

    Matched MeSH terms: Sequence Alignment
  11. Intra- and inter-specific variation of four acetes species (crustacea: decapoda: sergestidae) sampled along the west coast of peninsular Malaysia
    Boon Yee Wong, Taranjeet Kaur Awtar Singh, Gideon Khoo, Han Kiat Alan Ong
    Sains Malaysiana, 2017;46:2393-2416.
    The intra- and inter-specific variation of Acetes shrimps were evaluated based on samples collected from in-shore catches and off-shore trawling around the west coast of Peninsular Malaysia. Species captured were identified as Acetes indicus, A. serrulatus, A. japonicus and A. sibogae. A region of the mitochondrial cytochrome c oxidase subunit I (COI) gene comprising 552 base pairs (bp) was amplified from 159 Acetes specimens. The sequence alignment analysis generated phylogenetic trees which depicted the four major clades that were consistent with the species identified morphologically. These four species varied considerably for haplotype and nucleotide diversity, with A. indicus and A. serrulatus showing different demographic histories. Furthermore, the observation of two clades in the A. indicus and A. sibogae lineages, with relatively high levels of intraspecific divergence, suggests that cryptic diversity is possibly present in these two taxa. This study has contributed to the knowledge of the distribution patterns and molecular phylogenetics of four Acetes spp. in the Straits of Malacca.
    Matched MeSH terms: Sequence Alignment
  12. A context evaluation approach for structural comparison of proteins using cross entropy over n-gram modelling
    Razmara J, Deris SB, Parvizpour S
    Comput Biol Med, 2013 Oct;43(10):1614-21.
    PMID: 24034753 DOI: 10.1016/j.compbiomed.2013.07.022
    The structural comparison of proteins is a vital step in structural biology that is used to predict and analyse a new unknown protein function. Although a number of different techniques have been explored, the study to develop new alternative methods is still an active research area. The present paper introduces a text modelling-based technique for the structural comparison of proteins. The method models the secondary and tertiary structure of proteins in two linear sequences and then applies them to the comparison of two structures. The technique used for pairwise comparison of the sequences has been adopted from computational linguistics and its well-known techniques for analysing and quantifying textual sequences. To this end, an n-gram modelling technique is used to capture regularities between sequences, and then, the cross-entropy concept is employed to measure their similarities. Several experiments are conducted to evaluate the performance of the method and compare it with other commonly used programs. The assessments for information retrieval evaluation demonstrate that the technique has a high running speed, which is similar to other linear encoding methods, such as 3D-BLAST, SARST, and TS-AMIR, whereas its accuracy is comparable to CE and TM-align, which are high accuracy comparison tools. Accordingly, the results demonstrate that the algorithm has high efficiency compared with other state-of-the-art methods.
    Matched MeSH terms: Sequence Alignment/methods*
  13. A pattern matching approach for the estimation of alignment between any two given DNA sequences
    Basu K, Sriraam N, Richard RJ
    J Med Syst, 2007 Aug;31(4):247-53.
    PMID: 17685148
    For a given DNA sequence, it is well known that pair wise alignment schemes are used to determine the similarity with the DNA sequences available in the databanks. The efficiency of the alignment decides the type of amino acids and its corresponding proteins. In order to evaluate the given DNA sequence for its proteomic identity, a pattern matching approach is proposed in this paper. A block based semi-global alignment scheme is introduced to determine the similarity between the DNA sequences (known and given). The two DNA sequences are divided into blocks of equal length and alignment is performed which minimizes the computational complexity. The efficiency of the alignment scheme is evaluated using the parameter, percentage of similarity (POS). Four essential DNA version of the amino acids that emphasize the importance of proteomic functionalities are chosen as patterns and matching is performed with the known and given DNA sequences to determine the similarity between them. The ratio of amino acid counts between the two sequences is estimated and the results are compared with that of the POS value. It is found from the experimental results that higher the POS value and the pattern matching higher are the similarity between the two DNA sequences. The optimal block is also identified based on the POS value and amino acids count.
    Matched MeSH terms: Sequence Alignment/methods*
  14. Hybridization-ligation versus parallel overlap assembly: an experimental comparison of initial pool generation for direct-proportional length-based DNA computing
    Ibrahim Z, Tsuboi Y, Ono O
    IEEE Trans Nanobioscience, 2006 Jun;5(2):103-9.
    PMID: 16805106
    Previously, direct-proportional length-based DNA computing (DPLB-DNAC) for solving weighted graph problems has been reported. The proposed DPLB-DNAC has been successfully applied to solve the shortest path problem, which is an instance of weighted graph problems. The design and development of DPLB-DNAC is important in order to extend the capability of DNA computing for solving numerical optimization problem. According to DPLB-DNAC, after the initial pool generation, the initial solution is subjected to amplification by polymerase chain reaction and, finally, the output of the computation is visualized by gel electrophoresis. In this paper, however, we give more attention to the initial pool generation of DPLB-DNAC. For this purpose, two kinds of initial pool generation methods, which are generally used for solving weighted graph problems, are evaluated. Those methods are hybridization-ligation and parallel overlap assembly (POA). It is found that for DPLB-DNAC, POA is better than that of the hybridization-ligation method, in terms of population size, generation time, material usage, and efficiency, as supported by the results of actual experiments.
    Matched MeSH terms: Sequence Alignment/methods*
  15. Fulltext Prediction of antimicrobial peptides based on sequence alignment and support vector machine-pairwise algorithm utilizing LZ-complexity
    Ng XY, Rosdi BA, Shahrudin S
    Biomed Res Int, 2015;2015:212715.
    PMID: 25802839 DOI: 10.1155/2015/212715
    This study concerns an attempt to establish a new method for predicting antimicrobial peptides (AMPs) which are important to the immune system. Recently, researchers are interested in designing alternative drugs based on AMPs because they have found that a large number of bacterial strains have become resistant to available antibiotics. However, researchers have encountered obstacles in the AMPs designing process as experiments to extract AMPs from protein sequences are costly and require a long set-up time. Therefore, a computational tool for AMPs prediction is needed to resolve this problem. In this study, an integrated algorithm is newly introduced to predict AMPs by integrating sequence alignment and support vector machine- (SVM-) LZ complexity pairwise algorithm. It was observed that, when all sequences in the training set are used, the sensitivity of the proposed algorithm is 95.28% in jackknife test and 87.59% in independent test, while the sensitivity obtained for jackknife test and independent test is 88.74% and 78.70%, respectively, when only the sequences that has less than 70% similarity are used. Applying the proposed algorithm may allow researchers to effectively predict AMPs from unknown protein peptide sequences with higher sensitivity.
    Matched MeSH terms: Sequence Alignment/methods
  16. Fulltext Distinct genetic lineages of Bactrocera caudata (Insecta: Tephritidae) revealed by COI and 16S DNA sequences
    Lim PE, Tan J, Suana IW, Eamsobhana P, Yong HS
    PLoS One, 2012;7(5):e37276.
    PMID: 22615962 DOI: 10.1371/journal.pone.0037276
    The fruit fly Bactrocera caudata is a pest species of economic importance in Asia. Its larvae feed on the flowers of Cucurbitaceae such as Cucurbita moschata. To-date it is distinguished from related species based on morphological characters. Specimens of B. caudata from Peninsular Malaysia and Indonesia (Bali and Lombok) were analysed using the partial DNA sequences of cytochrome c oxidase subunit I (COI) and 16S rRNA genes. Both gene sequences revealed that B. caudata from Peninsular Malaysia was distinctly different from B. caudata of Bali and Lombok, without common haplotype between them. Phylogenetic analysis revealed two distinct clades, indicating distinct genetic lineage. The uncorrected 'p' distance for COI sequences between B. caudata of Malaysia-Thailand-China and B. caudata of Bali-Lombok was 5.65%, for 16S sequences from 2.76 to 2.99%, and for combined COI and 16S sequences 4.45 to 4.46%. The 'p' values are distinctly different from intraspecific 'p' distance (0-0.23%). Both the B. caudata lineages are distinctly separated from related species in the subgenus Zeugodacus - B. ascita, B. scutellata, B. ishigakiensis, B. diaphora, B. tau, B. cucurbitae, and B. depressa. Molecular phylogenetic analysis indicates that the B. caudata lineages are closely related to B. ascita sp. B, and form a clade with B. scutellata, B. ishigakiensis, B. diaphora and B. ascita sp. A. This study provides additional baseline for the phylogenetic relationships of Bactrocera fruit flies of the subgenus Zeugodacus. Both the COI and 16S genes could be useful markers for the molecular differentiation and phylogenetic analysis of tephritid fruit flies.
    Matched MeSH terms: Sequence Alignment
  17. Fish chemokines 14, 20 and 25: A comparative statement on computational analysis and mRNA regulation upon pathogenic infection
    Arockiaraj J, Bhatt P, Kumaresan V, Dhayanithi NB, Arshad A, Harikrishnan R, et al.
    Fish Shellfish Immunol, 2015 Nov;47(1):221-30.
    PMID: 26363233 DOI: 10.1016/j.fsi.2015.09.015
    In this study, we reported a molecular characterization of three CC chemokines namely, CsCC-Chem14, CsCC-Chem20 and CsCC-Chem25 which are were identified from the established cDNA library of striped murrel Channa striatus. Multiple sequence alignment of all the three chemokines revealed the presence of gene specific domains and motifs including small cytokine domain, IL8 like domain, receptor binding site and glycosaminoglycan (GAG) binding sites. Three dimensional structures of the chemokines under study showed an important facet on their anti-microbial property. Tissue specific mRNA expression showed that the CsCC-Chem14 is highly expressed in spleen, CsCC-Chem20 in liver and CsCC-Chem25 in trunk kidney. On challenge C. striatus with oomycete fungus Aphanomyces invadans, both CsCC-Chem20 and CsCC-Chem25 showed significant (P < 0.05) up-regulation compared to CsCC-Chem14. The increase in the expression levels of CsCC-Chem20 and CsCC-Chem25 due to infection showed that they are antimicrobial proteins. But considering the CsCC-Chem14 expression, it is found to be a constitutive chemokine and is involved in homeostatic function in spleen of C. striatus. C. striatus challenged with bacteria Aeromonas hydrophila also exhibited different up-regulation pattern in all the three chemokines at various time points. However, extensive studies are required to determine the functional activities of CsCC-Chem14, CsCC-Chem20 and CsCC-Chem25 in vitro and in vivo to gain more knowledge at the molecular and proteomic levels.
    Matched MeSH terms: Sequence Alignment
  18. Sequences of E/NS1 gene junction from four dengue-2 viruses of northeastern Thailand and their evolutionary relationships with other dengue-2 viruses
    Zin K, Morita K, Igarashi A
    Microbiol. Immunol., 1995;39(8):581-90.
    PMID: 7494497
    We determined the 240-nucleotide sequences of the E/NS1 gene junction of four dengue-2 viruses by the primer extension dideoxy chain termination method. These viruses were isolated from dengue patients with different clinical severities in Nakhon Phanom, Northeastern Thailand in 1993. The results were compared with the 52 published dengue-2 sequences of the same gene region. Sequence divergence of four new isolates varied from 4.17% to 5.42% compared with dengue-2 prototype New Guinea C strain whereas it varied from 5.42% to 6.67% and from 6.67% to 7.09% when compared with Jamaica 1409 strain and PR159/S1 strain, respectively. All nucleotide substitutions were found at the 3rd position of the codons which were silent mutations. All 56 isolates studied were classified into five genotypic groups by constructing the dendrogram. The results indicated that four new isolates from Northeastern Thailand belong to genotype II of dengue virus serotype 2, and were most closely related to prototype New Guinea C strain. We also observed the variation in nucleotide and amino acid sequences among clusters of isolates (Thailand-1980, Malaysia-1989 and Thailand-1993) which were obtained from the dengue patients with different clinical severities. The significance of these genetic differences have been discussed in terms of the possible correlation between genetic variability and virulence.
    Matched MeSH terms: Sequence Alignment
  19. Protein replenishment in pitcher fluids of Nepenthes × ventrata revealed by quantitative proteomics (SWATH-MS) informed by transcriptomics
    Wan Zakaria WNA, Aizat WM, Goh HH, Mohd Noor N
    J Plant Res, 2019 Sep;132(5):681-694.
    PMID: 31422552 DOI: 10.1007/s10265-019-01130-w
    Carnivorous plants capture and digest insects for nutrients, allowing them to survive in soil deprived of nitrogenous nutrients. Plants from the genus Nepenthes produce unique pitchers containing secretory glands, which secrete enzymes into the digestive fluid. We performed RNA-seq analysis on the pitcher tissues and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis on the pitcher fluids of Nepenthes × ventrata to study protein expression in this carnivory organ during early days of pitcher opening. This transcriptome provides a sequence database for pitcher fluid protein identification. A total of 32 proteins of diverse functions were successfully identified in which 19 proteins can be quantified based on label-free quantitative proteomics (SWATH-MS) analysis while 16 proteins were not reported previously. Our findings show that certain proteins in the pitcher fluid were continuously secreted or replenished after pitcher opening, even without any prey or chitin induction. We also discovered a new aspartic proteinase, Nep6, secreted into pitcher fluid. This is the first SWATH-MS analysis of protein expression in Nepenthes pitcher fluid using a species-specific reference transcriptome. Taken together, our study using a gel-free shotgun proteomics informed by transcriptomics (PIT) approach showed the dynamics of endogenous protein secretion in the digestive organ of N. × ventrata and provides insights on protein regulation during early pitcher opening prior to prey capture.
    Matched MeSH terms: Sequence Alignment
  20. Substrate docking and molecular dynamic simulation for prediction of fungal enzymes from Trichoderma species-assisted extraction of nanocellulose from oil palm leaves
    Bahaman AH, Abdul Wahab R, Hamid AAA, Halim KBA, Kaya Y, Edbeib MF
    J Biomol Struct Dyn, 2020 Sep;38(14):4246-4258.
    PMID: 31608812 DOI: 10.1080/07391102.2019.1679667
    Fungi of the Trichoderma species are valued industrial enzymes in support of the 'zero-waste' technology to convert agro-industrial biomass into valuable products, i.e. nanocellulose (NC). In this study, an in silico approach using substrate docking and molecular dynamic (MD) simulation was used to predict the order of which the multilayers of cellulosic polymers, i.e. lignin, hemicellulose and cellulose in oil palm leaves (OPL) are degraded by fungal enzymes, endocellulase and exocellulase. The study aimed to establish the catalytic tendencies of the enzymes to optimally degrade the cellulosic components of OPL for high yield production of NC. Energy minimized endocellulase and exocellulase models revealed satisfactory scores of PROCHECK (90.0% and 91.2%), Verify3D (97.23% and 98.85%) and ERRAT (95.24% and 91.00%) assessments. Active site prediction by blind docking, COACH meta-server and multiple sequence alignment indicated the catalytic triads for endocellulase and exocellulase were Ser116-His205-Glu249 and Ser382-Arg124-Asp385, respectively. Binding energy of endocellulase docked with hemicellulose (-6.0   kcal mol-1) was the most favourable followed by lignin (-5.6   kcal mol-1) and cellulose (-4.4   kcal mol-1). Exocellulase, contrarily, bonded favorably with lignin (-8.7   kcal mol-1), closely followed by cellulose (-8.5   kcal mol-1) and hemicellulose (-8.4   kcal mol-1). MDs simulations showed that interactions of complexes, endocellulase-hemicellulose and the exocellulase-cellulose being the most stable. Thus, the findings of the study successfully identified the specific actions of sugar-acting enzymes for NC production. Communicated by Ramaswamy H. Sarma.
    Matched MeSH terms: Sequence Alignment
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