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1.
Cancer Sci ; 114(2): 449-462, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36285479

RESUMO

Breast cancer is among the most common malignant cancers in women. B-cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) is a transcriptional repressor that has been shown to be involved in tumorigenesis, the cell cycle, and stem cell maintenance. In our study, increased expression of BMI-1 was found in both human triple negative breast cancer and luminal A-type breast cancer tissues compared with adjacent tissues. We also found that knockdown of BMI-1 significantly suppressed cell proliferation and migration in vitro and in vivo. Further mechanistic research demonstrated that BMI-1 directly bound to the promoter region of CDKN2D/BRCA1 and inhibited its transcription in MCF-7/MDA-MB-231. More importantly, we discovered that knockdown of CDKN2D/BRCA1 could promote cell proliferation and migration after repression by PTC-209. Our results reveal that BMI-1 transcriptionally suppressed BRCA1 in TNBC cell lines whereas, in luminal A cell lines, CDKN2D was the target gene. This provides a reference for the precise treatment of different types of breast cancer in clinical practice.


Assuntos
Neoplasias de Mama Triplo Negativas , Animais , Camundongos , Humanos , Feminino , Índice de Massa Corporal , Neoplasias de Mama Triplo Negativas/metabolismo , Fatores de Transcrição/genética , Linhagem Celular , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
2.
BMC Microbiol ; 23(1): 99, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37046215

RESUMO

BACKGROUND: As highly-conserved types of lipid flippases among fungi, P4-ATPases play a significant role in various cellular processes. Cdc50 acts as the regulatory subunit of flippases, forming heterodimers with Drs2 to translocate aminophospholipids. Cdc50 homologs have been reported to be implicated in protein trafficking, drug susceptibility, and virulence in Saccharomyces cerevisiae, Candida albicans and Cryptococcus neoformans. It is likely that Cdc50 has an extensive influence on fungal cellular processes. The present study aimed to determine the function of Cdc50 in Candida glabrata by constructing a Δcdc50 null mutant and its complemented strain. RESULTS: In Candida glabrata, the loss of Cdc50 led to difficulty in yeast budding, probably caused by actin depolarization. The Δcdc50 mutant also showed hypersensitivity to azoles, caspofungin, and cell wall stressors. Further experiments indicated hyperactivation of the cell wall integrity pathway in the Δcdc50 mutant, which elevated the major cell wall contents. An increase in exposure of ß-(1,3)-glucan and chitin on the cell surface was also observed through flow cytometry. Interestingly, we observed a decrease in the phagocytosis rate when the Δcdc50 mutant was co-incubated with THP-1 macrophages. The Δcdc50 mutant also exhibited weakened virulence in nematode survival tests. CONCLUSION: The results suggested that the lipid flippase subunit Cdc50 is implicated in yeast budding and cell wall integrity in C. glabrata, and thus have a broad influence on drug susceptibility and virulence. This work highlights the importance of lipid flippase, and offers potential targets for new drug research.


Assuntos
Adenosina Trifosfatases , Saccharomyces cerevisiae , Adenosina Trifosfatases/metabolismo , Saccharomyces cerevisiae/metabolismo , Candida glabrata/genética , Candida glabrata/metabolismo , Caspofungina , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
3.
J Biol Chem ; 290(22): 14192-207, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-25770214

RESUMO

Spider venom is a complex mixture of bioactive peptides to subdue their prey. Early estimates suggested that over 400 venom peptides are produced per species. In order to investigate the mechanisms responsible for this impressive diversity, transcriptomics based on second generation high throughput sequencing was combined with peptidomic assays to characterize the venom of the tarantula Haplopelma hainanum. The genes expressed in the venom glands were identified, and the bioactivity of their protein products was analyzed using the patch clamp technique. A total of 1,136 potential toxin precursors were identified that clustered into 90 toxin groups, of which 72 were novel. The toxin peptides clustered into 20 cysteine scaffolds that included between 4 and 12 cysteines, and 14 of these groups were newly identified in this spider. Highly abundant toxin peptide transcripts were present and resulted from hypermutation and/or fragment insertion/deletion. In combination with variable post-translational modifications, this genetic variability explained how a limited set of genes can generate hundreds of toxin peptides in venom glands. Furthermore, the intraspecies venom variability illustrated the dynamic nature of spider venom and revealed how complex components work together to generate diverse bioactivities that facilitate adaptation to changing environments, types of prey, and milking regimes in captivity.


Assuntos
Proteômica/métodos , Venenos de Aranha/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Cisteína/química , DNA Complementar/metabolismo , Etiquetas de Sequências Expressas , Deleção de Genes , Dados de Sequência Molecular , Mutação , Neurônios/metabolismo , Neurotoxinas/química , Técnicas de Patch-Clamp , Peptídeos/química , Filogenia , Processamento de Proteína Pós-Traducional , Ratos , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Aranhas , Transcrição Gênica
4.
J Org Chem ; 79(23): 11619-30, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25387225

RESUMO

1,3,5-Tri(1H-benzo[d]imidazol-2-yl)benzene derivatives, as a new kind of fluorescent chemosensor for the detection of nitroaromatic explosives, are designed and synthesized by simple N-hydrocarbylation. Among 16 obtained compounds, compound 4g has the best capability for detection of picric acid (PA), having good selectivity and high sensitivity. The detection of PA with 4g solution-coated paper strips at the picogram level is developed. A simple, portable, and low-cost method is provided for detecting PA in solution and contact mode.

5.
J Org Chem ; 79(17): 8366-73, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25122575

RESUMO

A new kind of supramolecular columnar liquid crystal T-A with a broad mesomorphic range (up to 164.9 °C), good thermal stability, and strong fluorescence is designed and formed by the H-bonding between 1,3,5-tri(1H-benzo[d]imidazol-2-yl)benzene (T) and serial gallic acid derivatives (A). Two components are easily available because of simple routes, common reactions, high yields, commercial starting materials, and inexpensive catalysts. The introduction of the 1,2,3-triazole structure into component A makes the textures different and is slightly disadvantageous for the T-A complexes.

6.
World J Gastrointest Oncol ; 16(4): 1421-1436, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660653

RESUMO

BACKGROUND: Metabolic reprogramming plays a key role in cancer progression and clinical outcomes; however, the patterns and primary regulators of metabolic reprogramming in colorectal cancer (CRC) are not well understood. AIM: To explore the role of nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) in promoting progression of CRC. METHODS: We evaluated the expression and function of dysregulated and survival-related metabolic genes using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Consensus clustering was used to cluster CRC based on dysregulated metabolic genes. A prediction model was constructed based on survival-related metabolic genes. Sphere formation, migration, invasion, proliferation, apoptosis and clone formation was used to evaluate the biological function of NOX4 in CRC. mRNA sequencing was utilized to explore the alterations of gene expression NOX4 over-expression tumor cells. In vivo subcutaneous and lung metastasis mouse tumor model was used to explore the effect of NOX4 on tumor growth. RESULTS: We comprehensively analyzed 3341 metabolic genes in CRC and identified three clusters based on dysregulated metabolic genes. Among these genes, NOX4 was highly expressed in tumor tissues and correlated with worse survival. In vitro, NOX4 overexpression induced clone formation, migration, invasion, and stemness in CRC cells. Furthermore, RNA-sequencing analysis revealed that NOX4 overexpression activated the mitogen-activated protein kinase-MEK1/2-ERK1/2 signaling pathway. Trametinib, a MEK1/2 inhibitor, abolished the NOX4-mediated tumor progression. In vivo, NOX4 overexpression promoted subcutaneous tumor growth and lung metastasis, whereas trametinib treatment can reversed the metastasis. CONCLUSION: Our study comprehensively analyzed metabolic gene expression and highlighted the importance of NOX4 in promoting CRC metastasis, suggesting that trametinib could be a potential therapeutic drugs of CRC clinical therapy targeting NOX4.

7.
FEMS Yeast Res ; 13(4): 386-93, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23480635

RESUMO

The widespread use of azoles has led to increasing azole resistance among Candida albicans strains. One mechanism of azole resistance involves point mutations in the ERG11 gene, which encodes the target enzyme (cytochrome P450 lanosterol 14α-demethylase). In the present study, we amplified and sequenced the ERG11 gene of 23 C. albicans clinical isolates. Seventeen mutations encoding distinct amino acid substitutions were found, of which seven (K143Q, Y205E, A255V, E260V, N435V, G472R, and D502E) were novel. We further verified the contribution of the amino acid substitutions to azole resistance using site-directed mutagenesis of the ERG11 gene to recreate these mutations for heterologous expression in Saccharomyces cerevisiae. We observed that substitutions A114S, Y132H, Y132F, K143R, Y257H, and a new K143Q substitution contributed to significant increases (≧fourfold) in fluconazole and voriconazole resistance; changes in itraconazole resistance were not significant (≦twofold).


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica , Mutação de Sentido Incorreto , Substituição de Aminoácidos , Candida albicans/isolamento & purificação , Candidíase/microbiologia , Sistema Enzimático do Citocromo P-450/metabolismo , Análise Mutacional de DNA , DNA Fúngico/química , DNA Fúngico/genética , Humanos , Mutagênese Sítio-Dirigida , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Análise de Sequência de DNA
8.
ScientificWorldJournal ; 2013: 184964, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24288464

RESUMO

Acidithiobacillus ferrooxidans (A. ferrooxidans) was applied in coal biodesulfurization and coal's pyrite bioleaching. The result showed that A. ferrooxidans had significantly promoted the biodesulfurization of coal and bioleaching of coal's pyrite. After 16 days of processing, the total sulfur removal rate of coal was 50.6%, and among them the removal of pyritic sulfur was up to 69.9%. On the contrary, after 12 days of processing, the coal's pyrite bioleaching rate was 72.0%. SEM micrographs showed that the major pyrite forms in coal were massive and veinlets. It seems that the bacteria took priority to remove the massive pyrite. The sulfur relative contents analysis from XANES showed that the elemental sulfur (28.32%) and jarosite (18.99%) were accumulated in the biotreated residual coal. However, XRD and XANES spectra of residual pyrite indicated that the sulfur components were mainly composed of pyrite (49.34%) and elemental sulfur (50.72%) but no other sulfur contents were detected. Based on the present results, we speculated that the pyrite forms in coal might affect sulfur biooxidation process.


Assuntos
Acidithiobacillus/metabolismo , Carvão Mineral , Ferro/química , Sulfetos/química , Enxofre/química , Ferro/metabolismo , Sulfetos/metabolismo , Enxofre/metabolismo
9.
Zhonghua Nei Ke Za Zhi ; 52(10): 833-7, 2013 Oct.
Artigo em Zh | MEDLINE | ID: mdl-24378060

RESUMO

OBJECTIVE: To evaluate the standardization of Meta-analyses on nephropathy published in Chinese journals. METHODS: By searching in WANFANG, VIP, CNKI databases and Chinese Biomedical Literature Database (CBM) as well as related Chinese journals, eligible Meta-analyses were enrolled and analyzed according to the PRISMA(Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Statement and the MOOSE (Meta-analysis of Observational Studies in Epidemiology) Checklist. RESULTS: A total of 217 Meta-analyses were enrolled with 166 on randomized controlled trials (RCT) and 51 on observational studies. Based on the PRSIMA Statement, of the 166 Meta-analyses on RCT, 51.8% (86 papers) were found with the complete research hypothesis, 13.9% (23) with the literature screening flow chart, 15.7% (26) with the subgroup analysis, 53.0% (88) with the publication bias analysis and 28.3% (47) with the sensitivity analysis. According to the MOOSE Checklist, of the 51 Meta-analyses on observational studies, only 9.8% (5) had done the statistical stability calculation, 54.9% (28) with the outlook of application, 45.1% (23) with the limitation of the study, 2.0% (1) with the quantitative analysis on potential bias and 17.6% (9) with the suggestion for future studies. CONCLUSIONS: Unclear hypothesis, limited methodological description, lack of in-depth analysis on heterogeneity and bias are the common defects in Meta-analyses published in Chinese journals on nephrology.


Assuntos
Nefropatias , Metanálise como Assunto , Publicações Periódicas como Assunto , Projetos de Pesquisa
10.
Front Cell Infect Microbiol ; 13: 1321094, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239503

RESUMO

Introduction: Candida glabrata has emerged as a fungal pathogen with high infection and mortality rates, and its primary virulence factors are related to adhesion and biofilm formation. These virulence factors in C.glabrata are primarily mediated by epithelial adhesins (Epas), most of which are encoded in subtelomeric regions and regulated by subtelomeric silencing mechanisms. The transcription factor Mss11, known for its regulatory role in adhesion, biofilm formation, and filamentous growth in Saccharomyces cerevisiae and Candida albicans, has also been implicated in the expression of EPA6, suggesting its potential influence on C.glabrata virulence. The present study aims to determine the regulatory role of Mss11 in the virulence of C. glabrata. Methods: In this work, a Δmss11 null mutant and its complemented strain were constructed from a C.glabrata standard strain. The impact of the transcription factor Mss11 on the virulence of C.glabrata was investigated through a series of phenotypic experiments, including the microbial adhesion to hydrocarbons (MATH) test, adherence assay, biofilm assay, scanning electron microscopy and Galleria mellonella virulence assay. Furthermore, transcriptome sequencing, quantitative reverse transcription polymerase chain reaction (RT-qPCR), and chromatin immunoprecipitation sequencing (ChIP-seq) were employed to investigate the molecular mechanisms behind the regulation of Mss11. Results: In C.glabrata, the loss of MSS11 led to a significant reduction in several virulence factors including cell surface hydrophobicity, epithelial cell adhesion, and biofilm formation. These observations were consistent with the decreased virulence of the Δmss11 mutant observed in the Galleria mellonella infection model. Further exploration demonstrated that Mss11 modulates C. glabrata virulence by regulating EPA1 and EPA6 expression. It binds to the upstream regions of EPA1 and EPA6, as well as the promoter regions of the subtelomeric silencing-related genes SIR4, RIF1, and RAP1, indicating the dual regulatory role of Mss11. Conclusion: Mss11 plays a crucial role in C. glabrata adhesion and biofilm formation, and thus has a broad influence on virulence. This regulation is achieved by regulating the expression of EPA1 and EPA6 through both promoter-specific regulation and subtelomeric silencing.


Assuntos
Candida glabrata , Proteínas de Saccharomyces cerevisiae , Candida glabrata/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Virulência/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Saccharomyces cerevisiae/metabolismo , Adesão Celular , Biofilmes , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Proteínas Repressoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Ligação a Telômeros/metabolismo
11.
Cancer Med ; 12(14): 15704-15719, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37306188

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is the subtype of breast cancer with the worst prognosis, and it is highly heterogeneous. There is growing evidence that the tumor immune microenvironment (TIME) plays a crucial role in tumor development, maintenance, and treatment responses. Notably however, the full effects of the TIME on prognosis, TIME characteristics, and immunotherapy responses in TNBC patients have not been fully elucidated. METHODS: Gene Expression Omnibus and The Cancer Genome Atlas data were used to data analysis. Single-cell sequencing and tissue microarray analysis were used to investigate gene expression. The concentrations and distributions of immune cell types were determined and analyzed using the CIBERSORT strategy. Tumor immune dysfunction and exclusion score and the IMvigor210 cohort were used to estimate the sensitivity of TNBC patients with different prognostic statuses to immune checkpoint treatment. RESULTS: Five immune-related genes associated with TNBC prognosis (IL6ST, NR2F1, CKLF, TCF7L2, and HSPA2) was identified and a prognostic evaluation model was constructed based on those genes. The respective areas under the curve of the prognostic nomogram model at 3 and 5 years were 0.791 and 0.859. The group with a lower nomogram score, with a better prognosis survival status and clinical treatment benefit rate. CONCLUSION: A prognostic model for TNBC that was closely related to the immune landscape and therapeutic responses was constructed. This model may help clinicians to make more precise and personalized treatment decisions pertaining to TNBC patients.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Prognóstico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Imunoterapia , Nomogramas , Análise de Dados , Microambiente Tumoral/genética
12.
Cell Death Dis ; 14(10): 696, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875515

RESUMO

As a common malignant tumor among women, ovarian cancer poses a serious threat to their health. This study demonstrates that long non-coding RNA NRSN2-AS1 is over-expressed in ovarian cancer tissues using patient sample and tissue microarrays. In addition, NRSN2-AS1 is shown to promote ovarian cancer cell proliferation and metastasis both in vitro and in vivo. Mechanistically, NRSN2-AS1 stabilizes protein tyrosine kinase 2 (PTK2) to activate the ß-catenin pathway via repressing MG-53-mediated ubiquitinated degradation of PTK2, thereby facilitating ovarian cancer progression. Rescue experiments verify the function of the NRSN2-AS1/PTK2/ß-catenin axis and the effects of MG53 on this axis in ovarian cancer cells. In conclusion, this study demonstrates the key role of the NRSN2-AS1/PTK2/ß-catenin axis for the first time and explores its potential clinical applications in ovarian cancer.


Assuntos
Neoplasias Ovarianas , RNA Longo não Codificante , Humanos , Feminino , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Cateninas/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Via de Sinalização Wnt/genética , Movimento Celular/genética , Quinase 1 de Adesão Focal/metabolismo
13.
Cancers (Basel) ; 14(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36230863

RESUMO

Gastric cancer is the most common malignancy of the human digestive system. Long noncoding RNAs (lncRNAs) influence the occurrence and development of gastric cancer in multiple ways. However, the function and mechanism of LINC01526 in gastric cancer remain unknown. Herein, we investigated the function of LINC01526 with respect to the malignant progression of gastric cancer. We found that LINC01526 was upregulated in gastric cancer cells and tissues. The function experiments in vitro and the Xenograft mouse model in vivo proved that LINC01526 could promote gastric cancer cell proliferation and migration. Furthermore, LINC01526 interacted with TAR (HIV-1) RNA-binding protein 2 (TARBP2) and decreased the mRNA stability of G protein gamma 7 (GNG7) through TARBP2. Finally, the rescue assay showed that downregulating GNG7 partially rescued the cell proliferation inhibited by LINC01526 or TARBP2 silencing. In summary, LINC01526 promoted gastric cancer progression by interacting with TARBP2, which subsequently degraded GNG7 mRNA. This study not only explores the role of LINC01526 in gastric cancer, but also provides a laboratory basis for its use as a new biomarker for diagnosis and therapeutic targets.

14.
Braz J Microbiol ; 53(2): 727-738, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35122657

RESUMO

BACKGROUND: The Candida glabrata does not develop into a pathogenic hiphal form; however, it has become the second most common pathogen of fungal infections in humans, partly because of its adhesion ability and virulence. OBJECTIVES: The present study aimed to determine whether Flo8, a transcription factor that plays an important role in the virulence and drug resistance in Candida albicans, has a similar role in C. glabrata. METHODS: We constructed FLO8 null strains of a C. glabrata standard strain and eight clinical strains from different sources, and a FLO8 complemented strain. Real-time quantitative PCR, biofilm formation assays, hydrophobicity tests, adhesion tests, Caenorhabditis elegans survival assay, and drug-susceptibility were then performed. RESULTS: Compared with the wild-type strains, the biofilm formation, hydrophobicity, adhesion, and virulence of the FLO8-deficient strains decreased, accompanied by decreased expression of EPA1, EPA6, and EPA7. On the other hand, it showed no changes in antifungal drug resistance, although the expression levels of CDR1, CDR2, and SNQ2 increased after FLO8 deletion. CONCLUSIONS: These results indicated that Flo8 is involved in the adhesion and virulence of C. glabrata, with FLO8 deletion leading to decreased expression of EPA1, EPA6, and EPA7 and decreased biofilm formation, hydrophobicity, adhesion, and virulence.


Assuntos
Candida glabrata , Proteínas Fúngicas , Antifúngicos/farmacologia , Biofilmes , Candida albicans/metabolismo , Candida glabrata/genética , Candida glabrata/metabolismo , Farmacorresistência Fúngica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Humanos , Virulência
16.
Eur J Pediatr ; 170(5): 661-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21107604

RESUMO

UNLABELLED: Hyper IgE syndrome (HIES) is a rare primary immunodeficiency disorder, characterized by eczema, recurrent skin and lung infections, and significantly elevated serum IgE level. It was previously diagnosed based on clinical manifestations and laboratory markers that were not specific to the disease. Recent studies have demonstrated that mutations in signal transducer and activator of transcription 3 (STAT3) cause the autosomal dominant or sporadic HIES, which make the disease definitively characterized at molecular level. Here, we reported a 3-year old Chinese boy with neonatal-onset rash and multiple serious Staphylococcus aureus infections including recurrent skin abscesses, liver abscess, sepsis, and destructive pulmonary infection (pneumonia, multiple pulmonary abscesses, pyopneumothorax, and finally, pneumatocele). Genetic study revealed a heterozygous mutation in exon 21 of STAT3 gene (g.66583 A > C, c.1970A > C) in the boy, which resulted in a substitution of tyrosine at the amino acid position 657 to serine (p.Y657S) in the Src homology 2 (SH2) domain of STAT3. Functional prediction with bioinformatics programs of the Sorting Intolerant from Tolerant (SIFT) and the Polymorphism Phenotyping (PolyPhen) reported "deleterious (SIFT score 0.02)" and "probably damaging (PSIC score difference 2.94)" values, respectively. Further study of family members revealed that neither his parents, nor his twin brother carried the mutation, indicating the mutation was likely to occur de novo in our patient. CONCLUSION: The mutation,p.Y657S,in SH2 domain of STAT3 is a disease-causing mutation in the boy with HIES.


Assuntos
Doenças em Gêmeos/genética , Síndrome de Job/genética , Mutação Puntual , Fator de Transcrição STAT3/genética , Pré-Escolar , Análise Mutacional de DNA , Heterozigoto , Humanos , Síndrome de Job/complicações , Síndrome de Job/diagnóstico , Pneumopatias/etiologia , Masculino , Infecções Estafilocócicas/etiologia , Gêmeos Dizigóticos
17.
Braz J Microbiol ; 51(4): 2183, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32794079

RESUMO

Unfortunately, an error occurred in the author affiliations.

18.
Braz J Microbiol ; 51(4): 1553-1561, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32648240

RESUMO

The wide use of antifungal agents has led to the development of resistance in the pathogenic yeast strain Candida albicans. Gain-of-function mutations in transcription factors such as Tac1p demonstrated their ability to control expression of the ABC transporter genes CDR1 and CDR2, and mediation of azole resistance. Previously, we obtained a series of azole-resistant isolates with high-level expression of CDR1 or/and CDR2, and identified the novel H741D mutation in Tac1p. In the present study, the TAC1 alleles from isolate C13 were introduced into tac1Δ/Δ mutant. The H741D change was seen in TAC1C13 in addition to several other amino acid differences. Hyperactive alleles TAC1C13 exhibited higher minimum inhibitory concentrations (MICs) of fluconazole and itraconazole than that observed in SN152 containing the wild-type TAC1 allele. And alleles TAC1C13 conferred constitutively high levels of Cdr1p and Cdr2p. Moreover, the importance of H741D in conferring hyperactivity to TAC1 was also confirmed by site-directed mutagenesis. Compared with SN152, the presence of H741D resulted in > 2-fold increase in CDR1 and CDR2 gene and protein expression, > 4-fold increase in fluconazole and itraconazole MICs and higher rates of Rhodamine 6G efflux by 43.24%.


Assuntos
Candida albicans/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Fatores de Transcrição/genética , Fluconazol/farmacologia , Regulação Fúngica da Expressão Gênica , Itraconazol/farmacologia , Mutação
19.
Braz J Microbiol ; 51(4): 1665-1672, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32557281

RESUMO

With the high-frequency use or abuse of antifungal drugs, the crisis of drug-resistant fungi continues to increase worldwide; in particular, the infection of drug-resistant Candida albicans brings the great challenge to the clinical treatment. Therefore, to decelerate the spread of this resistance, it is extremely urgent to facilitate the new antifungal targets with novel drugs. Phosphopantetheinyl transferases PPTases (Ppt2 in Candida albicans) had been identified in bacterium and fungi and mammals, effects as a vital enzyme in the metabolism of organisms in C. albicans. Ppt2 transfers the phosphopantetheinyl group of coenzyme A to the acyl carrier protein Acp1 in mitochondria for the synthesis of lipoic acid that is essential for fungal respiration, so making Ppt2 an ideal target for antifungal drugs. In this study, 110 FDA-approved drugs were utilized to investigate the Ppt2 inhibition against drug-resistant Candida albicans by the improved fluorescence polarization experiments, which have enough druggability and structural variety under the novel strategy of drug repurposing. Thereinto, eight agents revealed the favourable Ppt2 inhibitory activities. Further, broth microdilution assay of incubating C. albicans with these eight drugs showed that pterostilbene, procyanidine, dichlorophen and tea polyphenol had the superior MIC values. In summary, these findings provide more valuable insight into the treatment of drug-resistant C. albicans.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Transferases (Outros Grupos de Fosfato Substituídos)/antagonistas & inibidores , Candida albicans/enzimologia , Reposicionamento de Medicamentos , Proteínas Fúngicas/antagonistas & inibidores , Testes de Sensibilidade Microbiana
20.
Res Microbiol ; 170(6-7): 272-279, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31449848

RESUMO

Candida albicans has the ability to switch reversibly between budding yeast, filamentous, pseudohypha, and hyphal forms, a process in which the transcription factor Flo8 plays an important role. This ability is important for the virulence and pathogenicity of C. albicans. To determine whether Flo8 plays a role in the regulation of drug sensitivity, we constructed a FLO8 null mutant flo8/flo8 from the parental strain SN152 and a Flo8-overexpressing strain, flo8/flo8::FLO8. The susceptibility of the isolates to antifungal agents was then evaluated using the agar dilution and broth microdilution methods. Expression of drug resistance-related genes by the isolates was investigated by real-time PCR. The flo8/flo8 mutation isolates exhibited increased resistance to fluconazole, voriconazole, and itraconazole compared with the wild-type and drug sensitivity was restored by FLO8 overexpression (flo8/flo8∷FLO8). Of seven drug resistance-related genes, the FLO8 null mutation resulted in increased CDR1 and CDR2 expression (1.60-fold and 5.27-fold, respectively) compared with SN152, while FLO8 overexpression resulted in decreased CDR1 expression (0.63-fold). These results suggest that Flo8 is involved in the susceptibility of C. albicans to antifungal azoles, with FLO8 deletion leading to constitutive overexpression of CDR1 and CDR2 and resistance to antifungal azoles.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida albicans/genética , Farmacorresistência Fúngica/genética , Transativadores/genética , Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Proteínas Fúngicas/genética , Deleção de Genes , Proteínas de Membrana Transportadoras/genética , Testes de Sensibilidade Microbiana , Proteínas Serina-Treonina Quinases/genética
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