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1.
High Educ Policy ; 35(2): 439-478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34594092

RESUMO

Managing education and research during pandemics has increased in importance since the onset of epidemics such as avian flu, SARS and now CoViD-19. Successful management in times of crisis ensures business continuity and institutional survival, making preparedness preceding an impending pandemic essential. Institutions of higher education (IHEs) must maintain balance between academic continuity and preventing morbidity during a pandemic crisis. To date, however, no general pandemic preparedness frameworks exist for IHEs. The aim of this paper is to report on the development of a Haddon matrix framework for IHE pandemic preparedness based on a scoping literature review of past IHE responses including pre-, during and post-pandemic phases. First, a review of previous global responses by IHEs during past pandemics was carried out. The review findings were then collated into a new IHE-centric Haddon matrix for pandemic preparedness. The content of the matrix is then illustrated through the documented responses of Malaysian universities during the early stages of the COVID-19 pandemic. The resulting IHE Haddon matrix can be used by universities as a general guide to identify preparedness gaps and intervention opportunities for business continuity during pandemics.

2.
Appl Microbiol Biotechnol ; 105(3): 899-907, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33427934

RESUMO

Psychrophiles are cold-living microorganisms synthesizing enzymes that are permanently active at almost near-zero temperatures. Psychrozymes are supposed to be structurally more flexible than their homologous proteins. This structural flexibility enables these proteins to undergo conformational changes during catalysis and improve catalytic efficiency at low temperatures. The outstanding characteristics of the psychrophilic enzymes have attracted the attention of the scientific community to utilize them in a wide variety of industrial and pharmaceutical applications. In this review, we first highlight the current knowledge of the cold-adaptation mechanisms of the psychrophiles. In the sequel, we describe the potential applications of the enzymes in different biotechnological processes specifically, in the production of industrial and pharmaceutical products. KEY POINTS: • Methods that organisms have evolved to survive and proliferate at cold environments. • The economic benefits due to their high activity at low and moderate temperatures. • Applications of the psychrophiles in biotechnological and pharmaceutical industry.


Assuntos
Aclimatação , Preparações Farmacêuticas , Adaptação Fisiológica , Temperatura Baixa , Enzimas , Temperatura
3.
Arch Microbiol ; 202(9): 2591-2597, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32607725

RESUMO

To date, the genus Parvularcula consists of 6 species and no potential application of this genus was reported. Current study presents the genome sequence of Parvularcula flava strain NH6-79 T and its cellulolytic enzyme analysis. The assembled draft genome of strain NH6-79 T consists of 9 contigs and 7 scaffolds with 3.68 Mbp in size and GC content of 59.87%. From a total of 3,465 genes predicted, 96 of them are annotated as glycoside hydrolases (GHs). Within these GHs, 20 encoded genes are related to cellulosic biomass degradation, including 12 endoglucanases (5 GH10, 4 GH5, and 3 GH51), 2 exoglucanases (GH9) and 6 ß-glucosidases (GH3). In addition, highest relative enzyme activities (endoglucanase, exoglucanase, and ß-glucosidase) were observed at 27th hour when the strain was cultured in the carboxymethyl cellulose/Avicel®-containing medium for 45 h. The combination of genome analysis with experimental studies indicated the ability of strain NH6-79 T to produce extracellular endoglucanase, exoglucanase, and ß-glucosidase. These findings suggest the potential of Parvularcula flava strain NH6-79 T in cellulose-containing biomass degradation and that the strain could be used in cellulosic biorefining process.


Assuntos
Alphaproteobacteria/enzimologia , Alphaproteobacteria/genética , Genoma Bacteriano/genética , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Composição de Bases , Biomassa , Celulase/genética , Celulase/metabolismo , Celulose/metabolismo , beta-Glucosidase/genética , beta-Glucosidase/metabolismo
4.
Protein Expr Purif ; 164: 105464, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31376486

RESUMO

Xylanases (EC 3.2.1.8) are essential enzymes due to their applications in various industries such as textile, animal feed, paper and pulp, and biofuel industries. Halo-thermophilic Rhodothermaceae bacterium RA was previously isolated from a hot spring in Malaysia. Genomic analysis revealed that this bacterium is likely to be a new genus of the family Rhodothermaceae. In this study, a xylanase gene (1140 bp) that encoded 379 amino acids from the bacterium was cloned and expressed in Escherichia coli BL21(DE3). Based on InterProScan, this enzyme XynRA1 contained a GH10 domain and a signal peptide sequence. XynRA1 shared low similarity with the currently known xylanases (the closest is 57.2-65.4% to Gemmatimonadetes spp.). The purified XynRA1 achieved maximum activity at pH 8 and 60 °C. The protein molecular weight was 43.1 kDa XynRA1 exhibited an activity half-life (t1/2) of 1 h at 60 °C and remained stable at 50 °C throughout the experiment. However, it was NaCl intolerant, and various types of salt reduced the activity. This enzyme effectively hydrolyzed xylan (beechwood, oat spelt, and Palmaria palmata) and xylodextrin (xylotriose, xylotetraose, xylopentaose, and xylohexaose) to produce predominantly xylobiose. This xylanase is the first functionally characterized enzyme from the bacterium, and this work broadens the knowledge of GH10 xylanases.


Assuntos
Proteínas de Bactérias/genética , Endo-1,4-beta-Xilanases/genética , Rhodothermus/genética , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Endo-1,4-beta-Xilanases/metabolismo , Escherichia coli/genética , Expressão Gênica , Vetores Genéticos/genética , Filogenia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Rhodothermus/química , Rhodothermus/isolamento & purificação , Rhodothermus/metabolismo , Alinhamento de Sequência , Especificidade por Substrato
5.
Int J Mol Sci ; 20(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075847

RESUMO

A halo-thermophilic bacterium, Roseithermus sacchariphilus strain RA (previously known as Rhodothermaceae bacterium RA), was isolated from a hot spring in Langkawi, Malaysia. A complete genome analysis showed that the bacterium harbors 57 glycoside hydrolases (GHs), including a multi-domain xylanase (XynRA2). The full-length XynRA2 of 813 amino acids comprises a family 4_9 carbohydrate-binding module (CBM4_9), a family 10 glycoside hydrolase catalytic domain (GH10), and a C-terminal domain (CTD) for type IX secretion system (T9SS). This study aims to describe the biochemical properties of XynRA2 and the effects of CBM truncation on this xylanase. XynRA2 and its CBM-truncated variant (XynRA2ΔCBM) was expressed, purified, and characterized. The purified XynRA2 and XynRA2ΔCBM had an identical optimum temperature at 70 °C, but different optimum pHs of 8.5 and 6.0 respectively. Furthermore, XynRA2 retained 94% and 71% of activity at 4.0 M and 5.0 M NaCl respectively, whereas XynRA2ΔCBM showed a lower activity (79% and 54%). XynRA2 exhibited a turnover rate (kcat) of 24.8 s-1, but this was reduced by 40% for XynRA2ΔCBM. Both the xylanases hydrolyzed beechwood xylan predominantly into xylobiose, and oat-spelt xylan into a mixture of xylo-oligosaccharides (XOs). Collectively, this work suggested CBM4_9 of XynRA2 has a role in enzyme performance.


Assuntos
Bactérias/enzimologia , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Variação Genética , Proteínas Mutantes/metabolismo , Tolerância ao Sal , Sequência de Aminoácidos , Endo-1,4-beta-Xilanases/genética , Cinética , Proteínas Mutantes/química , Filogenia , Domínios Proteicos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Eletricidade Estática , Especificidade por Substrato , Xilanos/metabolismo
6.
J Membr Biol ; 250(2): 133-144, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28280854

RESUMO

Complete elucidation of fertilization process at molecular level is one of the unresolved challenges in sexual reproduction studies, and understanding the molecular mechanism is crucial in overcoming difficulties in infertility and unsuccessful in vitro fertilization. Sperm-oocyte interaction is one of the most remarkable events in fertilization process, and deficiency in protein-protein interactions which mediate this interaction is a major cause of unexplained infertility. Due to detection of how the various defects of sperm-oocyte interaction can affect fertilization failure, different experimental methods have been applied. This review summarizes the current understanding of sperm-egg interaction mechanism during fertilization and also accumulates the different types of sperm-egg interaction abnormalities and their association with infertility. Several detection approaches regarding sperm-egg protein interactions and the associated defects are reviewed in this paper.


Assuntos
Infertilidade/metabolismo , Infertilidade/fisiopatologia , Óvulo/metabolismo , Óvulo/fisiologia , Espermatozoides/metabolismo , Espermatozoides/fisiologia , Animais , Feminino , Humanos , Masculino , Oócitos/metabolismo , Oócitos/fisiologia
7.
J Basic Microbiol ; 57(2): 151-161, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27859397

RESUMO

Anoxybacillus sp. SK 3-4 is a Gram-positive, rod-shaped bacterium and a member of family Bacillaceae. We had previously reported that the strain is an aluminum resistant thermophilic bacterium. This is the first report to provide a detailed analysis of the global transcriptional response of Anoxybacillus when the cells were exposed to 600 mg L-1 of aluminum. The transcriptome was sequenced using Illumina MiSeq sequencer. Total of 708 genes were differentially expressed (fold change >2.00) with 316 genes were up-regulated while 347 genes were down-regulated, in comparing to control with no aluminum added in the culture. Based on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, the majority of genes encoding for cell metabolism such as glycolysis, sulfur metabolism, cysteine and methionine metabolism were up-regulated; while most of the gene associated with tricarboxylic acid cycle (TCA cycle) and valine, leucine and isoleucine metabolism were down-regulated. In addition, a significant number of the genes encoding ABC transporters, metal ions transporters, and some stress response proteins were also differentially expressed following aluminum exposure. The findings provide further insight and help us to understand on the resistance of Anoxybacillus sp. SK 3-4 toward aluminium.


Assuntos
Alumínio/metabolismo , Anoxybacillus/efeitos dos fármacos , Anoxybacillus/genética , Perfilação da Expressão Gênica , Estresse Fisiológico , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas/genética , Análise de Sequência de DNA
8.
Int J Mol Sci ; 17(11)2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-27834916

RESUMO

Non-obstructive azoospermia is a severe infertility factor. Currently, the etiology of this condition remains elusive with several possible molecular pathway disruptions identified in the post-meiotic spermatozoa. In the presented study, in order to identify all possible candidate genes associated with azoospermia and to map their relationship, we present the first protein-protein interaction network related to azoospermia and analyze the complex effects of the related genes systematically. Using Online Mendelian Inheritance in Man, the Human Protein Reference Database and Cytoscape, we created a novel network consisting of 209 protein nodes and 737 interactions. Mathematical analysis identified three proteins, ar, dazap2, and esr1, as hub nodes and a bottleneck protein within the network. We also identified new candidate genes, CREBBP and BCAR1, which may play a role in azoospermia. The gene ontology analysis suggests a genetic link between azoospermia and liver disease. The KEGG analysis also showed 45 statistically important pathways with 31 proteins associated with colorectal, pancreatic, chronic myeloid leukemia and prostate cancer. Two new genes and associated diseases are promising for further experimental validation.


Assuntos
Azoospermia/genética , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Mapas de Interação de Proteínas/genética , Algoritmos , Azoospermia/metabolismo , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Proteína Substrato Associada a Crk/genética , Proteína Substrato Associada a Crk/metabolismo , Bases de Dados Genéticas , Ontologia Genética , Humanos , Masculino , Modelos Genéticos , Mapeamento de Interação de Proteínas/métodos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
9.
J Basic Microbiol ; 55(4): 514-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25523650

RESUMO

The Anoxybacillus sp. SK 3-4, previously isolated from a hot spring, was screened for its heavy metals resistance (Al(3+), Mn(2+), Cu(2+), Co(2+), Zn(2+), and Ni(2+)) and the strain was found to be most resistant to aluminum. Significant growth of the strain was observed when it was grown in medium containing aluminum (200 mg L(-1)-800 mg L(-1)) with relative growth rates ranging between 77% and 100%. A gene encoding the aluminum resistance protein (accession number: WP_021095658.1) was found in genome of strain SK 3-4, which revealed high sequence identity (>95%) to its homologues from Anoxybacillus species. Sequence comparisons with two functionally characterized aluminum resistance proteins, namely G2alt and ALU1-P, showed 97% and 81% of sequence identity, respectively. Four putative metal binding sites were detected in SK 3-4 aluminum resistance protein and G2alt at same amino acid residue positions of 186, 195, 198, and 201. Strain SK 3-4 was found to be able to remove aluminum from aqueous solution. This study demonstrated that Anoxybacillus sp. SK 3-4 could be applied in the treatment of aluminum contaminated wastewater.


Assuntos
Alumínio/metabolismo , Alumínio/farmacologia , Anoxybacillus/genética , Anoxybacillus/isolamento & purificação , Fontes Termais/microbiologia , Metais Pesados/farmacologia , Águas Residuárias/microbiologia , Anoxybacillus/efeitos dos fármacos , Anoxybacillus/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Sítios de Ligação , Farmacorresistência Bacteriana , Genes Bacterianos , Concentração de Íons de Hidrogênio , Metais Pesados/metabolismo , Filogenia , RNA Ribossômico 16S/genética
10.
J Comput Aided Mol Des ; 28(6): 675-84, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24830925

RESUMO

The cluster-based compound selection is used in the lead identification process of drug discovery and design. Many clustering methods have been used for chemical databases, but there is no clustering method that can obtain the best results under all circumstances. However, little attention has been focused on the use of combination methods for chemical structure clustering, which is known as consensus clustering. Recently, consensus clustering has been used in many areas including bioinformatics, machine learning and information theory. This process can improve the robustness, stability, consistency and novelty of clustering. For chemical databases, different consensus clustering methods have been used including the co-association matrix-based, graph-based, hypergraph-based and voting-based methods. In this paper, a weighted cumulative voting-based aggregation algorithm (W-CVAA) was developed. The MDL Drug Data Report (MDDR) benchmark chemical dataset was used in the experiments and represented by the AlogP and ECPF_4 descriptors. The results from the clustering methods were evaluated by the ability of the clustering to separate biologically active molecules in each cluster from inactive ones using different criteria, and the effectiveness of the consensus clustering was compared to that of Ward's method, which is the current standard clustering method in chemoinformatics. This study indicated that weighted voting-based consensus clustering can overcome the limitations of the existing voting-based methods and improve the effectiveness of combining multiple clusterings of chemical structures.


Assuntos
Análise por Conglomerados , Bases de Dados de Produtos Farmacêuticos , Descoberta de Drogas , Algoritmos , Inteligência Artificial
11.
J Comput Aided Mol Des ; 28(6): 685-98, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24849507

RESUMO

The structure of a novel psychrophilic ß-mannanase enzyme from Glaciozyma antarctica PI12 yeast has been modelled and analysed in detail. To our knowledge, this is the first attempt to model a psychrophilic ß-mannanase from yeast. To this end, a 3D structure of the enzyme was first predicted using a threading method because of the low sequence identity (<30%) using MODELLER9v12 and simulated using GROMACS at varying low temperatures for structure refinement. Comparisons with mesophilic and thermophilic mannanases revealed that the psychrophilic mannanase contains longer loops and shorter helices, increases in the number of aromatic and hydrophobic residues, reductions in the number of hydrogen bonds and salt bridges and numerous amino acid substitutions on the surface that increased the flexibility and its efficiency for catalytic reactions at low temperatures.


Assuntos
Basidiomycota/enzimologia , beta-Manosidase/química , Aclimatação , Sequência de Aminoácidos , Basidiomycota/química , Basidiomycota/fisiologia , Temperatura Baixa , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Conformação Proteica , Alinhamento de Sequência , beta-Manosidase/metabolismo
12.
Biotechnol Biotechnol Equip ; 28(4): 608-615, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26740767

RESUMO

Halogenated compounds are recalcitrant environmental pollutants prevalent in agricultural fields, waste waters and industrial by-products, but they can be degraded by dehalogenase-containing microbes. Notably, 2-haloalkanoic acid dehalogenases are employed to resolve optically active chloropropionates, as exemplified by the d-specific dehalogenase from Rhizobium sp. RCI (DehD), which acts on d-2-chloropropionate but not on its l-enantiomer. The catalytic residues of this dehalogenase responsible for its affinity toward d-2-chloropropionate have not been experimentally determined, although its three-dimensional crystal structure has been solved. For this study, we performed in silico docking and molecular dynamic simulations of complexes formed by this dehalogenase and d- or l-2-chloropropionate. Arg134 of the enzyme plays the key role in the stereospecific binding and Arg16 is in a position that would allow it to activate a water molecule for hydrolytic attack on the d-2-chloropropionate chiral carbon for release of the halide ion to yield l-2-hydroxypropionate. We propose that within the DehD active site, the NH group of Arg134 can form a hydrogen bond with the carboxylate of d-2-chloropropionate with a strength of ∼4 kcal/mol that may act as an acid-base catalyst, whereas, when l-2-chloropropionate is present, this bond cannot be formed. The significance of the present work is vital for rational design of this dehalogenase in order to confirm the involvement of Arg16 and Arg134 residues implicated in hydrolysis and binding of d-2-chloropropionate in the active site of d-specific dehalogenase from Rhizobium sp. RC1.

13.
Biotechnol Biotechnol Equip ; 28(5): 949-957, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26019583

RESUMO

The D-2-haloacid dehalogenase of D-specific dehalogenase (DehD) from Rhizobium sp. RC1 catalyses the hydrolytic dehalogenation of D-haloalkanoic acids, inverting the substrate-product configuration and thereby forming the corresponding L-hydroxyalkanoic acids. Our investigations were focused on DehD mutants: R134A and Y135A. We examined the possible interactions between these mutants with haloalkanoic acids and characterized the key catalytic residues in the wild-type dehalogenase, to design dehalogenase enzyme(s) with improved potential for dehalogenation of a wider range of substrates. Three natural substrates of wild-type DehD, specifically, monochloroacetate, monobromoacetate and D,L-2,3-dichloropropionate, and eight other non-natural haloalkanoic acids substrates of DehD, namely, L-2-chloropropionate; L-2-bromopropionate; 2,2-dichloropropionate; dichloroacetate; dibromoacetate; trichloroacetate; tribromoacetate; and 3-chloropropionate, were docked into the active site of the DehD mutants R134A and Y135A, which produced altered catalytic functions. The mutants interacted strongly with substrates that wild-type DehD does not interact with or degrade. The interaction was particularly enhanced with 3-chloropropionate, in addition to monobromoacetate, monochloroacetate and D,L-2,3-dichloropropionate. In summary, DehD variants R134A and Y135A demonstrated increased propensity for binding haloalkanoic acid and were non-stereospecific towards halogenated substrates. The improved characteristics in these mutants suggest that their functionality could be further exploited and harnessed in bioremediations and biotechnological applications.

14.
Environ Microbiome ; 19(1): 29, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38706006

RESUMO

BACKGROUND: Hot spring biofilms provide a window into the survival strategies of microbial communities in extreme environments and offer potential for biotechnological applications. This study focused on green and brown biofilms thriving on submerged plant litter within the Sungai Klah hot spring in Malaysia, characterised by temperatures of 58-74 °C. Using Illumina shotgun metagenomics and Nanopore ligation sequencing, we investigated the microbial diversity and functional potential of metagenome-assembled genomes (MAGs) with specific focus on biofilm formation, heat stress response, and carbohydrate catabolism. RESULTS: Leveraging the power of both Illumina short-reads and Nanopore long-reads, we employed an Illumina-Nanopore hybrid assembly approach to construct MAGs with enhanced quality. The dereplication process, facilitated by the dRep tool, validated the efficiency of the hybrid assembly, yielding MAGs that reflected the intricate microbial diversity of these extreme ecosystems. The comprehensive analysis of these MAGs uncovered intriguing insights into the survival strategies of thermophilic taxa in the hot spring biofilms. Moreover, we examined the plant litter degradation potential within the biofilms, shedding light on the participation of diverse microbial taxa in the breakdown of starch, cellulose, and hemicellulose. We highlight that Chloroflexota and Armatimonadota MAGs exhibited a wide array of glycosyl hydrolases targeting various carbohydrate substrates, underscoring their metabolic versatility in utilisation of carbohydrates at elevated temperatures. CONCLUSIONS: This study advances understanding of microbial ecology on plant litter under elevated temperature by revealing the functional adaptation of MAGs from hot spring biofilms. In addition, our findings highlight potential for biotechnology application through identification of thermophilic lignocellulose-degrading enzymes. By demonstrating the efficiency of hybrid assembly utilising Illumina-Nanopore reads, we highlight the value of combining multiple sequencing methods for a more thorough exploration of complex microbial communities.

15.
J Biomol Struct Dyn ; 41(4): 1141-1167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34935583

RESUMO

Many studies reported that the activation of tumour suppressor protein, p53 induced the human hepcidin expression. However, its expression decreased when p53 was silenced in human hepatoma cells. Contrary to Tilapia hepcidin TH1-5, HepTH1-5 was previously reported to trigger the p53 activation through the molecular docking approach. The INhibitor of Growth (ING) family members are also shown to directly interact with p53 and promote cell cycle arrest, senescence, apoptosis and participate in DNA replication and DNA damage responses to suppress the tumour initiation and progression. However, the interrelation between INGs and HepTH1-5 remains unknown. Therefore, this study aims to identify the mechanism and their protein interactions using in silico approaches. The finding revealed that HepTH1-5 and its ligands had interacted mostly on hotspot residues of ING proteins which involved in histone modifications via acetylation, phosphorylation, and methylation. This proves that HepTH1-5 might implicate in an apoptosis signalling pathway and preserve the protein structure and function of INGs by reducing the perturbation of histone binding upon oxidative stress response. This study would provide theoretical guidance for the design and experimental studies to decipher the role of HepTH1-5 as a potential therapeutic agent for cancer therapy. Communicated by Ramaswamy H. Sarma.


Assuntos
Carcinoma Hepatocelular , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/genética , Hepcidinas , Simulação de Acoplamento Molecular , Proteínas Supressoras de Tumor/genética
16.
J Biomol Struct Dyn ; 41(2): 681-704, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34870559

RESUMO

Hepcidin is a principal regulator of iron homeostasis and its dysregulation has been recognised as a causative factor in cancers and iron disorders. The strategy of manipulating the presence of hepcidin peptide has been used for cancer treatment. However, this has demonstrated poor efficiency and has been short-lived in patients. Many studies reported using minihepcidin therapy as an alternative way to treat hepcidin dysregulation, but this was only applied to non-cancer patients. Highly conserved fish hepcidin protein, HepTH1-5, was investigated to determine its potential use in developing a hepcidin replacement for human hepcidin (Hepc25) and as a therapeutic agent by targeting the tumour suppressor protein, p53, through structure-function analysis. The authors found that HepTH1-5 is stably bound to ferroportin, compared to Hepc25, by triggering the ferroportin internalisation via Lys42 and Lys270 ubiquitination, in a similar manner to the Hepc25 activity. Moreover, the residues Ile24 and Gly24, along with copper and zinc ligands, interacted with similar residues, Lys24 and Asp1 of Hepc25, respectively, showing that those molecules are crucial to the hepcidin replacement strategy. HepTH1-5 interacts with p53 and activates its function through phosphorylation. This finding shows that HepTH1-5 might be involved in the apoptosis signalling pathway upon a DNA damage response. This study will be very helpful for understanding the mechanism of the hepcidin replacement and providing insights into the HepTH1-5 peptide as a new target for hepcidin and cancer therapeutics.Communicated by Ramaswamy H. Sarma.


Assuntos
Hepcidinas , Proteína Supressora de Tumor p53 , Animais , Humanos , Peptídeos/metabolismo , Ferro/metabolismo
17.
J Biomol Struct Dyn ; 41(19): 10037-10050, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36451602

RESUMO

Worldwide, breast cancer is the leading type of cancer among women. Overexpression of various prognostic indicators, including nuclear receptors, is linked to breast cancer features. To date, no effective drug has been discovered to block the proliferation of breast cancer cells. This study has been designed to discover target-based small molecular-like natural drug candidates that have anti-cancer potential without causing any serious side effects. A comprehensive substrate-based drug design was carried out to discover the potential plant compounds against the target breast cancer biomarkers including phytochemicals screening, active site identification, molecular docking, pharmacokinetic (PK) properties prediction, toxicity prediction, and molecular dynamics (MD) simulation approaches. Twenty plant compounds extracted from the rambutan (Nephelium lappaceum) were obtained from PubChem Database; and screened against the breast cancer biomarkers including estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR). The best docking interaction was chosen based on the higher binding affinity. Analyzing the pharmacokinetic properties and toxicity prediction results indicated that the fifteen selected plant compounds have good potency without toxicity and are safe for humans. Four phytochemicals with a higher binding affinity were chosen for each breast cancer biomarker to study their stability in interaction with the target proteins using MD simulation. Among the above compounds, Ellagic acid showed the high binding affinity against all three breast cancer biomarkers.Communicated by Ramaswamy H. Sarma.


Assuntos
Neoplasias da Mama , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Biomarcadores Tumorais , Neoplasias da Mama/tratamento farmacológico , Simulação de Acoplamento Molecular , Desenho de Fármacos , Simulação de Dinâmica Molecular
18.
PeerJ ; 11: e16419, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38089909

RESUMO

The spread of infectious illnesses has been a significant factor restricting aquaculture production. To maximise aquatic animal health, vaccination tactics are very successful and cost-efficient for protecting fish and aquaculture animals against many disease pathogens. However, due to the increasing number of immunological cases and their complexity, it is impossible to manage, analyse, visualise, and interpret such data without the assistance of advanced computational techniques. Hence, the use of immunoinformatics tools is crucial, as they not only facilitate the management of massive amounts of data but also greatly contribute to the creation of fresh hypotheses regarding immune responses. In recent years, advances in biotechnology and immunoinformatics have opened up new research avenues for generating novel vaccines and enhancing existing vaccinations against outbreaks of infectious illnesses, thereby reducing aquaculture losses. This review focuses on understanding in silico epitope-based vaccine design, the creation of multi-epitope vaccines, the molecular interaction of immunogenic vaccines, and the application of immunoinformatics in fish disease based on the frequency of their application and reliable results. It is believed that it can bridge the gap between experimental and computational approaches and reduce the need for experimental research, so that only wet laboratory testing integrated with in silico techniques may yield highly promising results and be useful for the development of vaccines for fish.


Assuntos
Doenças dos Peixes , Vacinas , Animais , Biologia Computacional/métodos , Vacinas/uso terapêutico , Epitopos , Doenças dos Peixes/prevenção & controle
19.
Fish Shellfish Immunol Rep ; 5: 100120, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37854946

RESUMO

Drug repurposing is a methodology of identifying new therapeutic use for existing drugs. It is a highly efficient, time and cost-saving strategy that offers an alternative approach to the traditional drug discovery process. Past in-silico studies involving molecular docking have been successful in identifying potential repurposed drugs for the various treatment of diseases including aquaculture diseases. The emerging shrimp hemocyte iridescent virus (SHIV) or Decapod iridescent virus 1 (DIV1) is a viral pathogen that causes severe disease and high mortality (80 %) in farmed shrimps caused serious economic losses and presents a new threat to the shrimp farming industry. Therefore, effective antiviral drugs are critically needed to control DIV1 infections. The aim of this study is to investigate the interaction of potential existing antiviral drugs, Chloroquine, Rimantadine, and CAP-1 with DIV1 major capsid protein (MCP) with the intention of exploring the potential of drug repurposing. The interaction of the DIV1 MCP and three antivirals were characterised and analysed using molecular docking and molecular dynamics simulation. The results showed that CAP-1 is a more promising candidate against DIV1 with the lowest binding energy of -8.46 kcal/mol and is more stable compared to others. We speculate that CAP-1 binding may induce the conformational changes in the DIV1 MCP structure by phosphorylating multiple residues (His123, Tyr162, and Thr395) and ultimately block the viral assembly and maturation of DIV1 MCP. To the best of our knowledge, this is the first report regarding the structural characterisation of DIV1 MCP docked with repurposing drugs.

20.
Mitochondrial DNA B Resour ; 8(2): 292-296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845007

RESUMO

In the present study, the nearly complete mitochondrial genome of Euphaea ochracea was described and its phylogenetic position in the family Euphaeidae was analyzed. Here, we recovered 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs and a partial control region, resulting in a mitogenome length of 15,545bp. All protein-coding genes were initiated by the typical ATN codon except nad3 and nad1, which utilizes the TTG codon. Four protein-coding genes (cox1, cox2, cox3 and nad5) are terminated by an incomplete stop codon T, while others end with either a TAA or TAG codon. The intergenic spacer region, S5, is absent in this mitogenome, supporting the lack of this region as a specific character in damselflies. Phylogenetic analysis showed that the newly sequenced E. ochracea is phylogenetically closer to E. ornata with a high support value.

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