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1.
Vet Res Commun ; 48(2): 623-632, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37863848

RESUMO

Anthrax is a serious infection caused by Bacillus anthracis. The anthracis spores are highly resistant and can persist in the environment for several decades. Therefore, anthrax is considered a global health threat affecting wildlife, livestock, and the general public. The resistance mechanism is influenced not only by the environment or the ecological niche but also by virulence factors. In the last 10 years the Southern and Southeastern Europe have been confronted with this threat. Recently, there have been 8 human anthrax cases reported in Croatia (2022), and 4 cases in Romania (2023). Moreover, this incident and the COVID situation could be a starting point to encourage researchers to raise the alarm. On the other hand, climate change is causing glaciers to melt and land to thaw, and many wetlands and swampy areas are being drained. It should not be forgotten that epidemiological and epizootic threats significantly affect the country's economic development. The Covid-19 epidemic best illustrates these threats.


Assuntos
Antraz , Bacillus anthracis , Saúde Única , Animais , Humanos , Antraz/epidemiologia , Antraz/veterinária , Mudança Climática , Animais Selvagens
2.
Molecules ; 28(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37764521

RESUMO

Small molecules as well as peptide-based therapeutic approaches have attracted global interest due to their lower or no toxicity in nature, and their potential in addressing several health complications including immune diseases, cardiovascular diseases, metabolic disorders, osteoporosis and cancer. This study proposed a peptide, GE18 of subtilisin-like peptidase from the virulence factor of aquatic pathogenic fungus Aphanomyces invadans, which elicits anti-cancer and anti-microbial activities. To understand the potential GE18 peptide-induced biological effects, an in silico analysis, in vitro (L6 cells) and in vivo toxicity assays (using zebrafish embryo), in vitro anti-cancer assays and anti-microbial assays were performed. The outcomes of the in silico analyses demonstrated that the GE18 peptide has potent anti-cancer and anti-microbial activities. GE18 is non-toxic to in vitro non-cancerous cells and in vivo zebrafish larvae. However, the peptide showed significant anti-cancer properties against MCF-7 cells with an IC50 value of 35.34 µM, at 24 h. Besides the anti-proliferative effect on cancer cells, the peptide exposure does promote the ROS concentration, mitochondrial membrane potential and the subsequent upregulation of anti-cancer genes. On the other hand, GE18 elicits significant anti-microbial activity against P. aeruginosa, wherein GE18 significantly inhibits bacterial biofilm formation. Since the peptide has positively charged amino acid residues, it targets the cell membrane, as is evident in the FESEM analysis. Based on these outcomes, it is possible that the GE18 peptide is a significant anti-cancer and anti-microbial molecule.


Assuntos
Aphanomyces , Animais , Aphanomyces/genética , Peixe-Zebra , Fungos , Peptídeos , Fatores de Virulência
3.
Toxicon ; 210: 100-108, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35217022

RESUMO

Peptide-based drug development is an emerging and promising approach in cancer therapeutics. The present study focuses on understanding the mechanism of MP12 peptide (MDNHVCIPLCPP) derived from cysteine-rich trypsin inhibitor protein of virulence factor of pathogenic fungus Aphanomyces invadans. MP12 is involved in antiproliferative activity against the human laryngeal epithelial cell (Hep-2), demonstrated in this study. MP12 sequence showed a significant binding score and has multiple hydrogen bond interactions with the proteins that play a vital role in apoptotic pathways such as Bcl-2, caspase-3, caspase-7, and XIAP. Based on the bioinformatics characterization and molecular docking result, further study was focused on MP12 antiproliferative activity. The peptide showed a dose-dependent inhibition against Hep-2 cell line proliferation, analyzed over MTT and neutral red uptake assays. The IC50 value of the MP12 peptide was calculated based on the antiproliferative property (24.7 ± 0.34 µM). MP12 treated Hep-2 cells showed significant shrinkage in cell morphology compared to untreated cells, inhibiting the cell cycle. The gene expression analysis validated that the MP12 significantly upregulates the caspase-3, caspase-7, and caspase-9 genes. The developmental toxicity study using zebrafish embryos as in vivo model proved that the MP12 is nontoxic. Based on the obtained results, we proposed that the peptide MP12 derived from cysteine-rich trypsin inhibitor protein of virulence molecule of pathogenic fungus have a potential antiproliferative activity. However, further clinical trials need to be focused on the mechanism and therapeutic application against laryngeal cancer.


Assuntos
Aphanomyces , Peixe-Zebra , Animais , Aphanomyces/genética , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Cisteína , Células Epiteliais , Fungos , Humanos , Simulação de Acoplamento Molecular , Inibidores da Tripsina , Fatores de Virulência
4.
J Biomol Struct Dyn ; 39(11): 3986-3995, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32448095

RESUMO

The host range of Brucella organisms has expanded from terrestrial and marine mammals to fish and amphibians. The high homology genomes of different Brucella organisms promote us to investigate evolutionary patterns for nucleotide, codon and amino acid usage patterns at gene levels among Brucella species. Although the similar patterns for nucleotide and synonymous codon usages exist in gene population, GC composition at the first codon position has significant correlations to that of the second and third codon positions, respectively, suggesting that nucleotide usages surrounding one codon influence synonymous codon usage patterns. Evolutionary patterns represented by synonymous codon and amino acid usages reflect host factor impacting Brucella speciation. As for genetic variations of important virulent factors involved with different biological functions, genes encoding lipoplysaccharides (LPSs) display more distinctive codon adaptation to Brucella than those of the BvrR/BvrS system and type IV secretion system. By Bayesian analysis, the polygenetic constructions for these genes of virulent factors shared by Brucella species display the purifying/positive selections and partially host factor in mediating genetic variations of these genes. The systemic analyses for nucleotide, synonymous codon and amino acid usages at gene level and genetic variations of important virulent factor genes display that host limitation influences either genetic characterizations at gene level or a particular gene involved in virulent factors of Brucella.Communicated by Ramaswamy H. Sarma.


Assuntos
Brucella , Nucleotídeos , Aminoácidos/genética , Animais , Teorema de Bayes , Brucella/genética , Códon/genética , Evolução Molecular , Especificidade de Hospedeiro
5.
Front Vet Sci ; 7: 582899, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240958

RESUMO

The presence of the plasmid-mediated colistin resistance encoding mcr gene family in the Enterobacteriaceae is one of the crucial global concerns. The use of colistin in livestock rearing is believed to be the cause of mcr gene spreading and is of impact to public health. The objective of this research was to detect the frequency and virulent genes of mcr-positive Escherichia coli (MCRPE) in fecal samples from healthy pigs in a contract farming system across Thailand. A total of 696 pooled samples were derived from 80 farms, located in 49 provinces across six regions of Thailand. The colistin-resistant E. coli were identified by MALDI-TOF mass spectrometry and antimicrobial susceptibility testing by broth microdilution. The antibiogram was determined using an automated susceptibility machine, and the genetic characteristics were investigated for mcr-1-5 genes, phylogenetic group, replicon types, and virulent genes. In total, 31 of 696 samples were positive, with E. coli containing mcr-1 or combination of mcr-1 and mcr-3 with incidence of 4.45 and 0.43%. Phylogenetic groups A and B1 and the IncF and IncFIB replicon types were predominantly found in the MCRPE located in the central area, with multidrug-resistant traits against 3-14 types of antimicrobials. Additionally, 19 of 31 isolates identified as enterotoxigenic E. coli were with the stap and stb (enterotoxin-encoding genes). In conclusion, a low carriage rate of mcr-positive E. coli was detected in the large-scale farming of healthy pigs. The association between multidrug-resistant MCRPE and their pathogenic potential should be of concern.

6.
Front Microbiol ; 10: 961, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130939

RESUMO

The protease high temperature requirement A from the gastric pathogen Helicobacter pylori (HtrA Hp ) belongs to the well conserved family of serine proteases. HtrA Hp is an important secreted virulence factor involved in the disruption of tight and adherens junctions during infection. Very little is known about the function of HtrA Hp in the H. pylori cell physiology due to the lack of htrA knockout strains. Here, using a newly constructed ΔhtrA mutant strain, we found that bacteria deprived of HtrA Hp showed increased sensitivity to certain types of stress, including elevated temperature, pH and osmotic shock, as well as treatment with puromycin. These data indicate that HtrA Hp plays a protective role in the H. pylori cell, presumably associated with maintenance of important periplasmic and outer membrane proteins. Purified HtrA Hp was shown to be very tolerant to a wide range of temperature and pH values. Remarkably, the protein exhibited a very high thermal stability with the melting point (Tm) values of above 85°C. Moreover, HtrA Hp showed the capability to regain its active structure following treatment under denaturing conditions. Taken together, our work demonstrates that HtrA Hp is well adapted to operate under harsh conditions as an exported virulence factor, but also inside the bacterial cell as an important component of the protein quality control system in the stressed cellular envelope.

7.
Microorganisms ; 7(4)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30979072

RESUMO

Probiotics per definition should have beneficial effects on human health, and their consumption has tremendously increased in the last decades. In parallel, the amount of published material and claims for their beneficial efficacy soared continuously. Recently, multiple systemic reviews, meta-analyses, and expert opinions expressed criticism on their claimed effects and safety. The present review describes the dark side of the probiotics, in terms of problematic research design, incomplete reporting, lack of transparency, and under-reported safety. Highlighted are the potential virulent factors and the mode of action in the intestinal lumen, risking the physiological microbiome equilibrium. Finally, regulatory topics are discussed to lighten the heterogeneous guidelines applied worldwide. The shift in the scientific world towards a better understanding of the human microbiome, before consumption of the probiotic cargo, is highly endorsed. It is hoped that better knowledge will extend the probiotic repertoire, re-confirm efficacy or safety, establish their efficacy and substantiate their beneficial effects.

8.
Bioinformation ; 12(3): 182-191, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28149053

RESUMO

Tuberculosis, a life threatening disease caused by different strains of Mycobacterium tuberculosis is creating an alarming condition due to the emergence of increasing multi drug resistance (MDR) trait. In this study, in silico approach was used for the identification of a conserved novel virulent factor in Mycobacterium tuberculosis EAI5 (Accession no.CP006578) which can also act as potential therapeutic target. Systematic comparative search of genes that are common to strain EAI5 and other human pathogenic strains of M. tuberculosis enlisted 408 genes. These were absent in the non-pathogenic Mycobacterium smegmatis MC2155 and in the human genome. Among those genes, only the protein coding hypothetical genes (97 out of 408) and their corresponding products were selected for further exploration. Of these, 11 proteins were found to have notable conserved domains, of which one hypothetical protein (NCBI Acc No. AGQ35418.1) was selected for further in silico exploration which was found to have two functional domains, one having phosphatidylinositol specific phospholipase C (PI-PLC) activity while the other short domain with weak lectin binding activity. As PI-PLC contributes virulence property in some pathogenic bacteria with a broad range of activities, different bioinformatic tools were used to explore its physicochemical and other important properties which indicated its secretary nature. This PI-PLC was previously not reported as drug/vaccine target to the best of our knowledge. Its predicted 3D structure can be explored for development of inhibitor for novel therapeutic strategies against MDR-TB.

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