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1.
Sci Rep ; 14(1): 910, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195813

RESUMO

Protection of the Critically Endangered East Asian Pangolin species is hampered by the vulnerability of captive individuals to infection. Studies have previously shown the pangolin to have a unique pseudogenisation of many immunity genes (including IFNE, IFIH1, cGAS, STING, TLR5, and TLR11), and we suspected that these losses could account for this vulnerability. Here we used RNA-Seq data to show the effect of these gene losses on the transcriptional response to a viral skin infection in a deceased pangolin. This virus is very closely related to the one causing the current COVID-19 pandemic in the human population (SARS-CoV2), and we found the most upregulated pathway was the same one previously identified in the lungs of SARS-CoV2-infected humans. As predicted, we found that the pathways downstream of the lost genes were not upregulated. For example, the pseudogenised interferon epsilon (IFNE) is known to be particularly important in epithelial immunity, and we show that interferon-related responses were not upregulated in the infected pangolin skin. We suggest that the pangolin's innate gene pseudogenisation is indeed likely to be responsible for the animal's vulnerability to infection.


Assuntos
Pandemias , Pangolins , Animais , Humanos , RNA Viral , RNA-Seq , Espécies em Perigo de Extinção , Interferons
2.
BMC Genomics ; 24(1): 734, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049764

RESUMO

BACKGROUND: Actinomyces strains are commonly found as part of the normal microflora on human tissue surfaces, including the oropharynx, gastrointestinal tract, and female genital tract. Understanding the diversity and characterization of Actinomyces species is crucial for human health, as they play an important role in dental plaque formation and biofilm-related infections. Two Actinomyces strains ATCC 49340 T and ATCC 51655 T have been utilized in various studies, but their accurate species classification and description remain unresolved. RESULTS: To investigate the genomic properties and taxonomic status of these strains, we employed both 16S rRNA Sanger sequencing and whole-genome sequencing using the Illumina HiSeq X Ten platform with PE151 (paired-end) sequencing. Our analyses revealed that the draft genome of Actinomyces acetigenes ATCC 49340 T was 3.27 Mbp with a 68.0% GC content, and Actinomyces stomatis ATCC 51655 T has a genome size of 3.08 Mbp with a 68.1% GC content. Multi-locus (atpA, rpoB, pgi, metG, gltA, gyrA, and core genome SNPs) sequence analysis supported the phylogenetic placement of strains ATCC 51655 T and ATCC 49340 T as independent lineages. Digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI), and average amino acid identity (AAI) analyses indicated that both strains represented novel Actinomyces species, with values below the threshold for species demarcation (70% dDDH, 95% ANI and AAI). Pangenome analysis identified 5,731 gene clusters with strains ATCC 49340 T and ATCC 51655 T possessing 1,515 and 1,518 unique gene clusters, respectively. Additionally, genomic islands (GIs) prediction uncovered 24 putative GIs in strain ATCC 49340 T and 16 in strain ATCC 51655 T, contributing to their genetic diversity and potential adaptive capabilities. Pathogenicity analysis highlighted the potential human pathogenicity risk associated with both strains, with several virulence-associated factors identified. CRISPR-Cas analysis exposed the presence of CRISPR and Cas genes in both strains, indicating these strains might evolve a robust defense mechanism against them. CONCLUSION: This study supports the classification of strains ATCC 49340 T and ATCC 51655 T as novel species within the Actinomyces, in which the name Actinomyces acetigenes sp. nov. (type strain ATCC 49340 T = VPI D163E-3 T = CCUG 34286 T = CCUG 35339 T) and Actinomyces stomatis sp. nov. (type strain ATCC 51655 T = PK606T = CCUG 33930 T) are proposed.


Assuntos
Actinomyces , Boca , Humanos , Feminino , Actinomyces/genética , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , Hibridização de Ácido Nucleico , Nucleotídeos , DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Ácidos Graxos/química
3.
PeerJ ; 11: e16476, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38084141

RESUMO

Background: Pseudomonas aeruginosa is a highly prevalent bacterial species known for its ability to cause various infections and its remarkable adaptability and biofilm-forming capabilities. In earlier work, we conducted research involving the screening of 33 metabolites obtained from a commercial source against two prevalent bacterial strains, Escherichia coli and Staphylococcus aureus. Through screening assays, we discovered a novel malic acid combination (MAC) consisting of malic acid, citric acid, glycine, and hippuric acid, which displayed significant inhibitory effects. However, the precise underlying mechanism and the potential impact of the MAC on bacterial biofilm formation remain unknown and warrant further investigation. Methods: To determine the antibacterial effectiveness of the MAC against Pseudomonas aeruginosa, we conducted minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques were employed to observe bacterial morphology and biofilm formation. We further performed a biofilm inhibition assay to assess the effect of the MAC on biofilm formation. Whole-transcriptome sequencing and bioinformatics analysis were employed to elucidate the antibacterial mechanism of the MAC. Additionally, the expression levels of differentially expressed genes were validated using the real-time PCR approach. Results: Our findings demonstrated the antibacterial activity of the MAC against P. aeruginosa. SEM analysis revealed that the MAC can induce morphological changes in bacterial cells. The biofilm assay showed that the MAC could reduce biofilm formation. Whole-transcriptome analysis revealed 1093 differentially expressed genes consisting of 659 upregulated genes and 434 downregulated genes, in response to the MAC treatment. Mechanistically, the MAC inhibited P. aeruginosa growth by targeting metabolic processes, secretion system, signal transduction, and cell membrane functions, thereby potentially compromising the survival of this human pathogen. This study provides valuable insights into the antibacterial and antibiofilm activities of the MAC, a synergistic and cost-effective malic acid combination, which holds promise as a potential therapeutic drug cocktail for treating human infectious diseases in the future.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Pseudomonas aeruginosa/genética , Antibacterianos/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Biofilmes , Perfilação da Expressão Gênica
4.
Nat Plants ; 9(9): 1389-1397, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37709954

RESUMO

In bacteria, fungi and animals, 3'-5'-cyclic adenosine monophosphate (cAMP) and adenylate cyclases (ACs), enzymes that catalyse the formation of 3',5'-cAMP from ATP, are recognized as key signalling components. In contrast, the presence of cAMP and its biological roles in higher plants have long been a matter of controversy due to the generally lower amounts in plant tissues compared with that in animal and bacterial cells, and a lack of clarity on the molecular nature of the generating and degrading enzymes, as well as downstream effectors. While treatment with 3',5'-cAMP elicited many plant responses, ACs were, however, somewhat elusive. This changed when systematic searches with amino acid motifs deduced from the conserved catalytic centres of annotated ACs from animals and bacteria identified candidate proteins in higher plants that were subsequently shown to have AC activities in vitro and in vivo. The identification of active ACs moonlighting within complex multifunctional proteins is consistent with their roles as molecular tuners and regulators of cellular and physiological functions. Furthermore, the increasing number of ACs identified as part of proteins with different domain architectures suggests that there are many more hidden ACs in plant proteomes and they may affect a multitude of mechanisms and processes at the molecular and systems levels.


Assuntos
Adenilil Ciclases , Proteoma , Animais , Adenilil Ciclases/genética , Catálise , Transdução de Sinais
5.
Sci Rep ; 13(1): 12548, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532809

RESUMO

Melanoma is a type of cancer with abnormal proliferation of melanocytes and is one of the most diagnosed cancer types. In traditional Chinese medicine, pangolin scales have been used to treat various diseases, including human cancers. However, its efficacy has not been scientifically proven. Here we studied the anticancer effect and mechanism of pangolin scale extract (PSE) on melanoma cell lines using scientific approaches. Our cell viability assay shows that PSE exhibits up to approximately 50-80% inhibition on SK-MEL-103 and A375 melanoma cell lines. Mechanically, PSE inhibits melanoma cell proliferation, migration, and causes changes in cell morphology. The apoptosis assay showed a significant chromosomal condensation inside the PSE-treated melanoma cells. The sequencing and analysis of A375 melanoma cell transcriptomes revealed 3077 differentially expressed genes in the 6 h treatment group and 8027 differentially expressed genes in the 72 h treatment group. Transcriptome analysis suggests that PSE may cause cell cycle arrest in melanoma cells and promote apoptosis mainly by up-regulating the p53 signaling pathway and down-regulating the PI3K-Akt signaling pathway. In this study, the anticancer effect of PSE was demonstrated by molecular biological means. PSE shows a significant inhibition effect on melanoma cell proliferation and cell migration in vitro, causes cell cycle arrest and promotes apoptosis through p53 and PI3K-AKT pathways. This study provides better insights into the anti-cancer efficacy and underlying mechanism of PSE and a theoretical basis for mining anticancer compounds or the development of new treatments for melanoma in the future. It is worth noting that this study does not advocate the use of the pangolin scale for disease treatment, but only to confirm its usefulness from a scientific research perspective and to encourage subsequent research around the development of active compounds to replace pangolin scales to achieve the conservation of this endangered species.


Assuntos
Escamas de Animais , Melanoma , Animais , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Escamas de Animais/metabolismo , Pangolins/metabolismo , Linhagem Celular Tumoral , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Proliferação de Células , Apoptose
6.
Int J Mol Sci ; 24(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37373523

RESUMO

Melanoma is a highly malignant skin cancer that is known for its resistance to treatments. In recent years, there has been significant progress in the study of non-apoptotic cell death, such as pyroptosis, ferroptosis, necroptosis, and cuproptosis. This review provides an overview of the mechanisms and signaling pathways involved in non-apoptotic cell death in melanoma. This article explores the interplay between various forms of cell death, including pyroptosis, necroptosis, ferroptosis, and cuproptosis, as well as apoptosis and autophagy. Importantly, we discuss how these non-apoptotic cell deaths could be targeted as a promising therapeutic strategy for the treatment of drug-resistant melanoma. This review provides a comprehensive overview of non-apoptotic processes and gathers recent experimental evidence that will guide future research and eventually the creation of treatment strategies to combat drug resistance in melanoma.


Assuntos
Ferroptose , Melanoma , Humanos , Apoptose/fisiologia , Morte Celular/fisiologia , Piroptose , Melanoma/tratamento farmacológico , Melanoma/patologia
7.
Eur J Med Chem ; 254: 115371, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37084597

RESUMO

The NaV1.8 channel is a genetically validated target for pain and it is mostly expressed in the peripheral nervous system. Based on the disclosed structures of NaV1.8-selective inhibitors, we designed and synthesized a series of compounds by introducing bicyclic aromatic fragments based on the nicotinamide scaffold. In this research, a systematic structure-activity relationship study was carried out. While compound 2c possessed moderate inhibitory activity (IC50 = 50.18 ± 0.04 nM) in HEK293 cells stably expressing human NaV1.8 channels, it showed potent inhibitory activity in DRG neurons and isoform selectivity (>200-fold against human NaV1.1, NaV1.5 and NaV1.7 channels). Moreover, the analgesic potency of compound 2c was identified in a post-surgical mouse model. These data demonstrate that compound 2c can be further evaluated as a non-addictive analgesic agent with reduced cardiac liabilities.


Assuntos
Canal de Sódio Disparado por Voltagem NAV1.7 , Niacinamida , Humanos , Camundongos , Animais , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Células HEK293 , Dor/tratamento farmacológico , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química
8.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499102

RESUMO

Melanoma is the most aggressive form of skin cancer, characterized by life-threatening and rapidly spreading progression. Traditional targeted therapy can alleviate tumors by inactivating hyperactive kinases such as BRAF or MEK but inevitably encounters drug resistance. The advent of immunotherapy has revolutionized melanoma treatment and significantly improved the prognosis of melanoma patients. MicroRNAs (miRNAs) are intricately involved in innate and adaptive immunity and are implicated in melanoma immunotherapy. This systematic review describes the roles of miRNAs in regulating the functions of immune cells in skin and melanoma, as well as the involvement of miRNAs in pharmacology including the effect, resistance and immune-related adverse events of checkpoint inhibitors such as PD-1 and CTLA-4 inhibitors, which are used for treating cutaneous, uveal and mucosal melanoma. The expressions and functions of miRNAs in immunotherapy employing tumor-infiltrating lymphocytes and Toll-like receptor 9 agonists are also discussed. The prospect of innovative therapeutic strategies such as the combined administration of miRNAs and immune checkpoint inhibitors and the nanotechnology-based delivery of miRNAs are also provided. A comprehensive understanding of the interplay between miRNAs and immunotherapy is crucial for the discovery of reliable biomarkers and for the development of novel miRNA-based therapeutics against melanoma.


Assuntos
Melanoma , MicroRNAs , Neoplasias Cutâneas , Humanos , MicroRNAs/genética , MicroRNAs/uso terapêutico , Melanoma/terapia , Melanoma/tratamento farmacológico , Imunoterapia/métodos , Neoplasias Cutâneas/terapia , Terapia Combinada
10.
Database (Oxford) ; 20222022 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-35962763

RESUMO

Drug resistance remains a global threat, and the rising trend of consuming probiotic-containing foods, many of which harbor antibiotic resistant determinants, has raised serious health concerns. Currently, the lack of accessibility to location-, drug- and species-specific information of drug-resistant probiotics has hampered efforts to combat the global spread of drug resistance. Here, we describe the development of ProbResist, which is a manually curated online database that catalogs reports of probiotic bacteria that have been experimentally proven to be resistant to antibiotics. ProbResist allows users to search for information of drug resistance in probiotics by querying with the names of the bacteria, antibiotic or location. Retrieved results are presented in a downloadable table format containing the names of the antibiotic, probiotic species, resistant determinants, region where the study was conducted and digital article identifiers (PubMed Identifier and Digital Object Identifier) hyperlinked to the original sources. The webserver also presents a simple analysis of information stored in the database. Given the increasing reports of drug-resistant probiotics, an exclusive database is necessary to catalog them in one platform. It will enable medical practitioners and experts involved in policy making to access this information quickly and conveniently, thus contributing toward the broader goal of combating drug resistance. DATABASE URL: https://probresist.com.


Assuntos
Probióticos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias
11.
Bioinformatics ; 38(19): 4643-4644, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-35993887

RESUMO

SUMMARY: HNOXPred is a webserver for the prediction of gas-sensing heme-nitric oxide/oxygen (H-NOX) proteins from amino acid sequence. H-NOX proteins are gas-sensing hemoproteins found in diverse organisms ranging from bacteria to eukaryotes. Recently, gas-sensing complex multi-functional proteins containing only the conserved amino acids at the heme centers of H-NOX proteins, have been identified through a motif-based approach. Based on experimental data and H-NOX candidates reported in the literature, HNOXPred is created to automate and facilitate the identification of similar H-NOX centers across systems. The server features HNOXSCORES scaled from 0 to 1 that consider in its calculation, the physicochemical properties of amino acids constituting the heme center in H-NOX in addition to the conserved amino acids within the center. From user input amino acid sequence, the server returns positive hits and their calculated HNOXSCORES ordered from high to low confidence which are accompanied by interpretation guides and recommendations. The utility of this server is demonstrated using the human proteome as an example. AVAILABILITY AND IMPLEMENTATION: The HNOXPred server is available at https://www.hnoxpred.com. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Hemeproteínas , Humanos , Hemeproteínas/metabolismo , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Sequência de Aminoácidos , Oxigênio/química , Oxigênio/metabolismo , Heme/química , Heme/metabolismo , Aminoácidos , NADPH Oxidases/metabolismo , Proteínas de Bactérias/metabolismo
13.
J Oral Microbiol ; 14(1): 2019992, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35024089

RESUMO

BACKGROUND: Probiotic lozenges have been developed to harvest the benefits of probiotics for oral health, but their long-term consumption may encourage the transfer of resistance genes from probiotics to commensals, and eventually to disease-causing bacteria. AIM: To screen commercial probiotic lozenges for resistance to antibiotics, characterize the resistance determinants, and examine their transferability in vitro. RESULTS: Probiotics of all lozenges were resistant to glycopeptide, sulfonamide, and penicillin antibiotics, while some were resistant to aminoglycosides and cephalosporins. High minimum inhibitory concentrations (MICs) were detected for streptomycin (>128 µg/mL) and chloramphenicol (> 512 µg/mL) for all probiotics but only one was resistant to piperacillin (MIC = 32 µg/mL). PCR analysis detected erythromycin (erm(T), ermB or mefA) and fluoroquinolone (parC or gyr(A)) resistance genes in some lozenges although there were no resistant phenotypes. The dfrD, cat-TC, vatE, aadE, vanX, and aph(3")-III or ant(2")-I genes conferring resistance to trimethoprim, chloramphenicol, quinupristin/dalfopristin, vancomycin, and streptomycin, respectively, were detected in resistant probiotics. The rifampicin resistance gene rpoB was also present. We found no conjugal transfer of streptomycin resistance genes in our co-incubation experiments. CONCLUSION: Our study represents the first antibiotic resistance profiling of probiotics from oral lozenges, thus highlighting the health risk especially in the prevailing threat of drug resistance globally.

14.
Trends Plant Sci ; 26(9): 885-897, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33867269

RESUMO

Nitric oxide (NO) sensing is an ancient trait enabled by hemoproteins harboring a highly conserved Heme-Nitric oxide/OXygen (H-NOX) domain that operates throughout bacteria, fungi, and animal kingdoms including in humans, but that has long thought to be absent in plants. Recently, H-NOX-containing plant hemoproteins mediating crucial NO-dependent responses such as stomatal closure and pollen tube guidance have been reported. There are indications that the detection method that led to these discoveries will uncover many more heme-based NO sensors that operate as regulatory sites in complex proteins. Their characterizations will in turn offer a much more complete picture of plant NO responses at both the molecular and systems level.


Assuntos
Hemeproteínas , Óxido Nítrico , Fenômenos Fisiológicos Vegetais , Heme , Oxigênio
16.
Front Bioinform ; 1: 652286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36303732

RESUMO

In proteins, functional centers consist of the key amino acids required to perform molecular functions such as catalysis, ligand-binding, hormone- and gas-sensing. These centers are often embedded within complex multi-domain proteins and can perform important cellular signaling functions that enable fine-tuning of temporal and spatial regulation of signaling molecules and networks. To discover hidden functional centers, we have developed a protocol that consists of the following sequential steps. The first is the assembly of a search motif based on the key amino acids in the functional center followed by querying proteomes of interest with the assembled motif. The second consists of a structural assessment of proteins that harbor the motif. This approach, that relies on the application of computational tools for the analysis of data in public repositories and the biological interpretation of the search results, has to-date uncovered several novel functional centers in complex proteins. Here, we use recent examples to describe a step-by-step guide that details the workflow of this approach and supplement with notes, recommendations and cautions to make this protocol robust and widely applicable for the discovery of hidden functional centers.

17.
Hortic Res ; 5: 68, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30393542

RESUMO

As indoor horticulture gathers momentum, electric (also termed artificial) lighting systems with the ability to generate specific and tunable wavelengths have been developed and applied. While the effects of light quality on plant growth and development have been studied, authoritative and reliable sets of light formulae tailored for the cultivation of economically important plants and plant traits are lacking as light qualities employed across laboratories are inconsistent. This is due, at least in part, to the lack of molecular data for plants examined under electric lights in indoor environments. It has hampered progress in the field of indoor horticulture, in particular, the transition from small-scale indoor farming to commercial plant factories. Here, we review the effects of light quality on model and crop plants studied from a physiological, physical and biochemical perspective, and explain how functional genomics can be employed in tandem to generate a wealth of molecular data specific for plants cultivated under indoor lighting. We also review the current state of lighting technologies in indoor horticulture specifically discussing how recent narrow-bandwidth lighting technologies can be tailored to cultivate economically valuable plant species and traits. Knowledge gained from a complementary phenotypic and functional genomics approach can be harvested not only for economical gains but also for sustainable food production. We believe that this review serves as a platform that guides future light-related plant research.

18.
Comput Struct Biotechnol J ; 16: 70-76, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977479

RESUMO

Plants are constantly exposed to environmental stresses and in part due to their sessile nature, they have evolved signal perception and adaptive strategies that are distinct from those of other eukaryotes. This is reflected at the cellular level where receptors and signalling molecules cannot be identified using standard homology-based searches querying with proteins from prokaryotes and other eukaryotes. One of the reasons for this is the complex domain architecture of receptor molecules. In order to discover hidden plant signalling molecules, we have developed a motif-based approach designed specifically for the identification of functional centers in plant molecules. This has made possible the discovery of novel components involved in signalling and stimulus-response pathways; the molecules include cyclic nucleotide cyclases, a nitric oxide sensor and a novel target for the hormone abscisic acid. Here, we describe the major steps of the method and illustrate it with recent and experimentally confirmed molecules as examples. We foresee that carefully curated search motifs supported by structural and bioinformatic assessments will uncover many more structural and functional aspects, particularly of signalling molecules.

19.
Front Microbiol ; 8: 908, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28579981

RESUMO

Probiotic bacteria are known to harbor intrinsic and mobile genetic elements that confer resistance to a wide variety of antibiotics. Their high amounts in dietary supplements can establish a reservoir of antibiotic resistant genes in the human gut. These resistant genes can be transferred to pathogens that share the same intestinal habitat thus resulting in serious clinical ramifications. While antibiotic resistance of probiotic bacteria from food, human and animal sources have been well-documented, the resistant profiles of probiotics from dietary supplements have only been recently studied. These products are consumed with increasing regularity due to their health claims that include the improvement of intestinal health and immune response as well as prevention of acute and antibiotic-associated diarrhea and cancer; but, a comprehensive risk assessment on the spread of resistant genes to human health is lacking. Here, we highlight recent reports of antibiotic resistance of probiotic bacteria isolated from dietary supplements, and propose complementary strategies that can shed light on the risks of consuming such products in the context of a global widespread of antibiotic resistance. In concomitant with a broader screening of antibiotic resistance in probiotic supplements is the use of computational simulations, live imaging and functional genomics to harvest knowledge on the evolutionary behavior, adaptations and dynamics of probiotics studied in conditions that best represent the human gut including in the presence of antibiotics. The underlying goal is to enable the health benefits of probiotics to be exploited in a responsible manner and with minimal risk to human health.

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