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1.
PLoS One ; 19(6): e0305373, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38843238

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0288991.].

2.
ChemMedChem ; : e202400109, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758596

RESUMO

Antibody-drug conjugates (ADCs) are consisted of antibodies, linker and payloads. They offer targeted delivery of potent cytotoxic drugs to tumor cells, minimizing off-target effects. However, the therapeutic efficacy of ADCs is compromised by the heterogeneity in the drug-to-antibody ratio (DAR), which impacts both cytotoxicity and pharmacokinetics (PK). Additionally, the emergence of drug resistance poses significant challenges to the clinical advancement of ADCs. To overcome these limitations, a variety of strategies have been developed, including the design of multi-specific drugs with accurate DAR. This review critically summarized the current challenges faced by ADCs, categorizing key issues and evaluating various innovative solutions. We provide an in-depth analysis of the latest methodologies for achieving homogeneous DAR and explore the design strategies for multi-specific drugs aimed at combating drug resistance. Our discussion offers insights into the progress made in refining ADC technologies, with a focus on enhancing therapeutic outcomes.

3.
Aging (Albany NY) ; 16(1): 402-430, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38189818

RESUMO

The global prevalence of breast cancer necessitates the development of innovative prognostic markers and therapeutic strategies. This study investigated the prognostic implications of anoikis-related long non-coding RNAs (ARLs) in invasive breast cancer (IBC), which is an area that has not been extensively explored. By integrating the RNA sequence transcriptome and clinical data from The Cancer Genome Atlas (TCGA) database and employing advanced regression analyses, we devised a novel prognostic model based on ARL scores. ARL scores correlated with diverse clinicopathological parameters, cellular pathways, distinct mutation patterns, and immune responses, thereby affecting both immune cell infiltration and anticipated responses to chemotherapy and immunotherapy. Additionally, the overexpression of a specific lncRNA, AL133467.1, significantly impeded the proliferation and migration, as well as possibly the anoikis resistance of breast cancer cells. These findings highlight the potential of the ARL signature as a robust prognostic tool and a promising basis for personalized IBC treatment strategies.


Assuntos
Neoplasias , RNA Longo não Codificante , Anoikis/genética , Prognóstico , RNA Longo não Codificante/genética , Biologia Computacional , Bases de Dados Factuais
4.
Parasitol Res ; 123(1): 30, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085374

RESUMO

Mites belonging to the suborder Gamasida are species-rich and habitat-diverse, with a worldwide distribution. To adapt to the environment and obtain better living conditions, all species of the suborder Gamasida have been undergoing constant evolution. The complete mitochondrial genome (mitogenome) is an invaluable molecular marker for studying the origin of species, genetic differentiation between closely related species, and between intraspecific groups. In some species of the suborder Gamasida, mitochondrial tRNA genes are truncated and carried unstable genetic information. This study presents a comparative analysis of codon usage pattern and preference of 13 protein-coding genes of 24 species in 17 genera and 10 families of the suborder Gamasida. Results showed that have an obvious AT preference (0.664-0.829) for codon usage in the suborder Gamasida. Most of the optimal and high-frequency codons also end in A/T. The degree of natural selection varies between the same protein-coding genes of different gamasid mites or among different protein-coding genes within the same gamasid mites. Base and codon usage pattern and preference are very similar between the same species and genus, namely the closer species, the more similar their bases and codons usage patterns and preference are. T bases and C bases were the preference bases for codon usage of 24 species in the suborder Gamasida. Evolution of the suborder Gamasida was dominated by natural selection (64.1%). This study provides the first comprehensive analysis of codon usage in the suborder Gamasida, which will greatly improve our understanding of codon usage patterns and preference, genetics, and evolution of the suborder Gamasida. It will help to evaluate the degree of molecular adaptation in the suborder Gamasida and to further explore evolutionary features of the suborder Gamasida.


Assuntos
Genoma Mitocondrial , Ácaros , Animais , Uso do Códon , Genes Mitocondriais , Códon/genética , Genoma Mitocondrial/genética , Ácaros/genética , Evolução Molecular , Seleção Genética
5.
PLoS One ; 18(12): e0288991, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38100410

RESUMO

BACKGROUND: Echinolaelaps fukienensis is the dominant mite species parasitic on the body surface of the genus Niviventer. The mitochondrial genome (mitogenome) has its own independent genetic material and genetic system, and is now widely used in population genetics, genealogical biogeography, phylogeny and molecular evolution studies. Species diversity of the superfamily Dermanyssoidea is very rich, but its mitogenomes AT content is high, and it is difficult to amplify the complete mitogenome by routine PCR. To date, we have only obtained the mitogenomes of 6 species, scarcity on sequence data has greatly impeded the studies in the superfamily Dermanyssoidea. METHODS: Echinolaelaps fukienensis were collected in 2019 from the body surface of Niviventer confucianus (Rodentia, Muridae) in Yunnan Province. The E. fukienensis mitogenome was determined and analyzed for the first time using the Illumina Novoseq 6000 platform. Phylogenetic analyses of the superfamily Dermanyssoidea were conducted based on the entire mitogenome sequences. RESULTS: The E. fukienensis mitogenome was 14,402 bp, which is known the smallest genome of the superfamily Dermanyssoidea, encoding a total of 37 genes, including 13 PCGs, 22 tRNAs, 2 rRNAs and 1 control region. Most protein-coding genes use ATN as the start codon and TAN as the stop codon. AT and GC skew of atp8 genes in E. fukienensis were both 0. The average length of 22 tRNA genes of E. fukienensis was 64 bp, and secondary structures of tRNAs showed base mismatches and missing D-arms in many places. Compared with gene arrangement pattern of the hypothetical ancestor of arthropods, the E. fukienensis mitogenome shows a novel arrangement pattern. Phylogenetic tree supported the monophyly of the superfamily Dermanyssoidea. Echinolaelaps fukienensis being the least genetic distant (0.2762) and most closely related to Varroa destructor. CONCLUSIONS: This study analyzed comprehensive the structure and evolution of the E. fukienensis mitogenome for the first time, enriches molecular data of the genus Echinolaelaps, which will contribute to further understand phylogeny and rearrangement patterns of the superfamily Dermanyssoidea.


Assuntos
Genoma Mitocondrial , Ácaros , Animais , Filogenia , Genoma Mitocondrial/genética , China , RNA de Transferência/genética , Ácaros/genética
6.
Parasites Hosts Dis ; 61(3): 272-281, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37648232

RESUMO

Chigger mites are the vector of scrub typhus. This study estimates the infestation status and ecological characteristics of chiggers on the chestnut white-bellied rat Niviventer fulvescens in Southwest China between 2001 and 2019. Chiggers were identified under the microscope, and infestation indices were calculated. The Preston's log-normal model was used to fit the curve of species abundance distribution. A total of 6,557 chiggers were collected in 136 of 342 N. fulvescens rats, showing high overall infestation indices (prevalence=39.8%, mean abundance=19.2, mean intensity=48.2) and high species diversity (S=100, H'=3.0). Leptotrombidium cangjiangense, Neotrombicula japonica, and Ascoschoengastia sifanga were the three dominant chigger species (constituent ratio=42.9%; 2,736/6,384) and exhibited an aggregated distribution among different rat individuals. We identified 100 chigger species, with 3 of them (Leptotrombidium scutellare, Leptotrombidium wenense, and Leptotrombidium deliense) as the main vectors of scrub typhus in China and nine species as potential vectors of this disease. Disease vector occurrence on N. fulvescens may increase the risk of spreading scrub typhus from rats to humans. Chigger infestation on N. fulvescens varied significantly in different environments. The species abundance distribution showed a log-normal distribution pattern. The estimated number of chigger species on N. fulvescens was 126 species.


Assuntos
Asteraceae , Infestações por Ácaros , Tifo por Ácaros , Trombiculidae , Humanos , Animais , Ratos , Murinae , China/epidemiologia , Vetores de Doenças
7.
Parasitology ; 150(9): 821-830, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37395062

RESUMO

In this study, the mitochondrial genome of Eulaelaps silvestris, which parasitizes Apodemus chevrieri, was sequenced and assembled to fill the gap in understanding the molecular evolution of the genus Eulaelaps. The E. silvestris mitochondrial genome is a double-stranded DNA molecule with a length of 14 882 bp, with a distinct AT preference for base composition and a notably higher AT content than GC content. The arrangement between genes is relatively compact, with a total of 10 gene intergenic regions and 12 gene overlap regions. All protein-coding genes had a typical ATN initiation codon, and only 2 protein-coding genes had an incomplete termination codon T. Out of the 13 protein-coding genes, the 5 most frequently used codons ended in A/U, with only 1 codon ending in G/C had an relative synonymous codon usage value >1. Except for trnS1 and trnS2, which lacked the D arm, all other tRNAs were able to form a typical cloverleaf structure; and there were a total of 38 mismatches in the folding process of tRNA genes. Unlike the gene arrangement order of the arthropod hypothetical ancestor, the E. silvestris mitochondrial genome underwent fewer rearrangements, mainly near tRNA genes and control regions. Both the maximum likelihood tree and the Bayesian tree showed that the family Haemogamasidae is most closely related to the family Dermanyssidae. The results not only provide a theoretical basis for studying the phylogenetic relationships of the genus Eulaelaps, but also provide molecular evidence that the family Haemogamasidae does not belong to the subfamily Laelapidae.


Assuntos
Genoma Mitocondrial , Animais , Filogenia , Teorema de Bayes , Sequência de Bases , RNA de Transferência/genética , Códon/genética , RNA Ribossômico/genética
8.
Exp Appl Acarol ; 90(3-4): 301-316, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37349609

RESUMO

Some mites of the family Haemogamasidae can transmit a variety of zoonotic diseases and have important public health and safety implications. Currently, however, little attention has been paid to molecular data of Haemogamasidae species, limiting our understanding of their evolutionary and phylogenetic relationships. In this study, the complete mitochondrial genome of Eulaelaps huzhuensis was determined for the first time, and its genomic information was analyzed in detail. The mitochondrial genome of E. huzhuensis is 14,872 bp in length with 37 genes and two control regions. The base composition showed a distinct AT preference. Twelve protein-coding genes have a typical ATN as the start codon, and three protein-coding genes have incomplete stop codons. During the folding of tRNA genes, a total of 30 mismatches occurred, and three tRNA genes had an atypical cloverleaf secondary structure. The order of the E. huzhuensis mitochondrial genome arrangement is a new type of rearrangement in Mesostigmata. The phylogenetic analysis confirmed that the family Haemogamasidae is a monophyletic branch and does not belong to a subfamily of the Laelapidae. Our results lay the foundation for subsequent studies on the phylogeny and evolutionary history of the family Haemogamasidae.


Assuntos
Genoma Mitocondrial , Ácaros , Animais , RNA Ribossômico/genética , Filogenia , Ácaros/genética , RNA de Transferência/genética
9.
Parasitology ; 150(7): 644-652, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37165885

RESUMO

Echinolaelaps echidninus is a gamasid mite that is of medical and veterinary significance as parasites and vectors of disease agents, which can carry pathogens of zoonosis such as Rickettsia tsutsugamushi, Rickettsia Q fever, Rickettsia mooseri, Rickettsia pox pathogens, Corynebacterium pseudotuberculosis and Leptospira. At present, only single mitochondrial genes have been analysed for E. echidninus in the world, and no complete mitochondrial genome has been reported. However, information carried by a single gene is limited. Therefore, the complete mitochondrial genome of E. echidninus was determined for the first time by Illumina Hiseq X-Ten platform in this study. The mitochondrial genome is 15 736 bp in length and contains 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a control region of 1561 bp in length. Codon analysis of 13 protein-coding genes revealed that UUU, UUA, AUU, AUA and AAU were the most frequently used, while cox2 had the fastest evolutionary rate and cob the slowest. Comparative analysis of genome structure and breakpoint distances of the mitochondrial genomes of 23 species in 17 genera from 10 families of Gamasida deposited in GenBank revealed a novel gene arrangement type of the E. echidninus mitochondrial genome, and different degrees of rearrangement among different taxa of Gamasida. Phylogenetic analyses of Gamasida were performed using the maximum likelihood and Bayesian inference methods. Echinolaelaps echidninus was clustered with Dermanyssoidea and formed a more supportive sister group with Varroa destructor. This study provides novel insights into rearrangement patterns and evolution of mitochondrial genomes of Gamasida.


Assuntos
Genoma Mitocondrial , Ácaros , Animais , Filogenia , Teorema de Bayes , Genes Mitocondriais , Ácaros/genética
10.
Appl Microbiol Biotechnol ; 107(7-8): 2639-2651, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36810625

RESUMO

Protein purification is a basic technology in both biological research and industrial production, and efficient, convenient, economical, and environmentally friendly purification methods have always been pursued. In this study, it was found that alkaline earth metal cations (Mg2+, Ca2+) and alkali metal cations (Li+, Na+, K+) and even nonmetal cations (e.g., NH4+, imidazole, guanidine, arginine, lysine) can precipitate multi-histidine-tagged proteins (at least two tags in a whole protein) at low salts concentrations that are 1-3 orders of magnitude lower than salting-out, and precipitated proteins could be dissolved at moderate concentration of corresponding cation. Based on this finding, a novel cation affinity purification method was developed, which requires only three centrifugal separations to obtain highly purified protein with purification fold similar to that of immobilized metal affinity chromatography. The study also provides a possible explanation for unexpected protein precipitation and reminds researchers to consider the influence of cations on the experimental results. The interaction between histidine-tagged proteins and cations may also have broad application prospects. KEY POINTS: • Histidine-tagged proteins can be precipitated by low-concentrations common cations • A novel nonchromatographic protein purification method was developed • Purified protein can be obtained in pellet form by only three centrifugations.


Assuntos
Histidina , Histidina/química , Histidina/metabolismo , Indicadores e Reagentes , Cátions , Cromatografia de Afinidade/métodos , Proteínas Recombinantes
11.
PLoS One ; 18(2): e0279598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36787294

RESUMO

Using the mitochondrial barcoding region to correlate research with 58 species in 19 genera of the family Laelapidae with the aim of determining the origin, phylogenetic relationships, and biogeographic historical distribution characteristics of mites in the family Laelapidae. Phylogenetic trees were obtained using Bayesian inference (BI) and Maximum-likelihood (ML) methods, based on three fossil records calibrated as molecular clock nodes, to estimate the divergence time of mites in the family Laelapidae as well as to apply Dispersal-Extinction-Cladogenesis (DEC) analyses to obtain biogeographic history inferences. The result showed species of the genera Hyperlaelaps and Haemolaelaps and some species of the genus Androlaelaps in the family Laelapidae were divided into clades of the genus Laelaps in both the BI and ML trees. Divergence time estimates and biogeographic history analysis revealed that the family Laelapidae likely diverged from other taxa during the Middle Jurassic (ca. 156.73 Mya), with Asia considered the most likely ancestral region for the family Laelapidae. Species of various genera began to undergo massive diversification events during the Cenozoic Tertiary. The results suggest that some genera in the family Laelapidae need to be re-defined or new genera need to be established; the Late Cretaceous to Late Neogene warm period would have promoted the divergence and expansion of species in the family Laelapidae. The divergence and dispersal of the family Laelapidae species is most likely a joint response to the continued northward drift of the Indian plate away from the Gondwana paleo-continent and gradually closer to Asia during the Late Cretaceous and the geological activity of the Tibetan Plateau during the Cenozoic Tertiary. The results strengthen our understanding of the origin and evolution of species in the family Laelapidae.


Assuntos
Ácaros , Animais , Filogenia , Teorema de Bayes , Ácaros/genética , Especiação Genética , Ásia
12.
Parasitology ; 150(2): 195-205, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36482713

RESUMO

Ticks are a group of blood-sucking ectoparasites that play an important role in human health and livestock production development as vectors of zoonotic diseases. The phylogenetic tree of single genes cannot accurately reflect the true kinship between species. Based on the complete mitochondrial genome analysis one can help to elucidate the phylogenetic relationships among species. In this study, the complete mitochondrial genome of Dermacentor steini (isolate Longyan) was sequenced and compared with the mitochondrial genes of 3 other Chinese isolates (Nanchang, Jinhua and Yingtan). In Dermacentor steini 4 isolates had identical or similar mitochondrial genome lengths and an overall variation of 0.76% between sequences. All nucleotide compositions showed a distinct AT preference. The most common initiation and stop codons were ATG and TAA, respectively. Fewer base mismatches were found in the tRNA gene of D. steini (isolate Longyan), and the vicinity of the control region and tRNA gene was a hot rearrangement region of the genus Dermacentor. Maximum likelihood trees and Bayesian trees indicate that D. steini is most closely related to Dermacentor auratus. The results enrich the mitochondrial genomic data of species in the genus Dermacentor and provide novel insights for further studies on the phylogeographic classification and molecular evolution of ticks.


Assuntos
Dermacentor , Genoma Mitocondrial , Animais , Humanos , Filogenia , DNA Mitocondrial/genética , Dermacentor/genética , Teorema de Bayes , RNA de Transferência/genética
13.
Endokrynol Pol ; 73(4): 680-689, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059163

RESUMO

INTRODUCTION: Thyroid carcinoma (THCA) is the most common endocrine malignancy. Recent research has shown heat shock protein family A (HSPA5) as a diagnostic and prognostic biomarker for various malignancies. Nevertheless, the role of HSPA5 in THCA is unclear. This study aims to explore HSPA5 expression in THCA and its potential diagnostic and therapeutic value for THCA. MATERIAL AND METHODS: We obtained the data of HSPA5 expression in THCA and normal thyroid tissues from the Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). We used the Shapiro-Wilk normality test, Levene's test, t-test, Dunn's test, Kruskal-Wallis test, Wilcoxon rank sum test, chi-square test, Fisher's exact test, and logistic regression to evaluate the relationship between the expression of HSPA5 and clinicopathological features. Kaplan-Meier method and Cox regression were applied to analyse the correlation between the expression level of HSPA5 and prognosis of THCA patients, and to construct a prognosis prediction model of THCA patients. Gene set enrichment analysis (GSEA) was applied to explore the potential pathway related to HSPA5 in THCA. RESULTS: HSPA5 expression was lower in THCA tissues than in normal thyroid tissues (p < 0.001). Low expression of HSPA5 in THCA patients was related to poorer T stage (p < 0.001), N stage (p < 0.001), pathologic stage (p < 0.001), tumour extrathyroidal extension (p < 0.001), residual tumour (p = 0.03), and progression-free interval (PFI) event (p = 0.002). Low HSPA5 expression was associated with poor PFI. According to the results of univariate analysis, THCA patients who had high HSPA5 levels had longer PFI (p = 0.042). Enrichment analysis via GO/KEGG showed that the top 10 genes related to HSPA5 were all enriched in the pathways related to endoplasmic reticulum function. Moreover, HSPA5 expression was related to immune infiltrating cells. CONCLUSIONS: Decreased expression of HSPA5 is associated with worse clinicopathological features, shorter PFI and higher immune infiltration level of multiple immune cells, which demonstrated that HSPA5 is a prognostic biomarker in THCA.


Assuntos
Neoplasias da Glândula Tireoide , Biomarcadores , Humanos , Prognóstico , Neoplasias da Glândula Tireoide/genética
14.
Korean J Parasitol ; 60(4): 273-279, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36041489

RESUMO

Laelapinae mites are involved in transmission of microbial diseases between wildlife and humans, with an impact on public health. In this study, 5 mite members in the subfamily Laelapinae (laelapin mites; LM) were morphologically identified by light microscopy, and the phylogenetic relationship of LM was analyzed in combination with the sequence information of part of the LM cytochrome oxidase subunit I (cox1) gene. The morphological identification revealed that 5 mites belonged to the genera Laelaps and Haemolaelaps, respectively. Sequence analysis showed that the ratio of non-synonymous mutation rate to synonymous mutation rate of LM was less than 1, indicating that the LM cox1 gene had undergone purifying selection. Phylogenetic analysis showed that the Laelapinae is a monophyletic group. The genera Haemolaelaps and Hyperlaelaps did not separated into distinct clades but clustered together with species of the genus Laelaps. Our morphological and molecular analyses to describe the phylogenetic relationships among different genera and species of Laelapinae provide a reference for the improvement and revision of the LM taxonomy system.


Assuntos
Ácaros , Filogenia , Animais , China , Ciclo-Oxigenase 1/genética , Ácaros/anatomia & histologia , Ácaros/genética
15.
Front Endocrinol (Lausanne) ; 13: 884777, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35733776

RESUMO

Hepatocellular carcinoma (HCC) is a global health challenge with an increasing incidence worldwide. Cancer-associated fibroblasts (CAFs) function critically in HCC initiation and development. However, the prognostic significance of CAF-related gene signatures in HCC remains unknown. Therefore, the specific functions of CAF-related genes in HCC were investigated to help develop potential therapeutic strategies. In this study, CAF-related genes were screened from three CAF-related gene sets. HCC data from the Gene Expression Omnibus (GEO) database was applied to verify the screened CAF-related genes. Cluster analysis was used to identify clusters based on the expression pattern of CAF-related genes and two identified clusters were found to have a significant difference in overall survival (OS) and progression free intervals (PFI). The prognosis of HCC patients was predicted using the prognostic risk score model developed based on HCC data from The Cancer Genome Atlas (TCGA) databases. High-risk group patients had a worse OS than those in low-risk group in TCGA. These results were validated in International Cancer Genome Consortium (ICGC) database. Moreover, combining the clinicopathological characteristics related to prognosis with the model, a nomogram was built for a more accurate prediction of OS of HCC patients. In addition, analyses of immune infiltration characteristics of tumor microenvironment (TME), chemosensitivity, and immunotherapy response were conducted to further evaluate the prognostic value of CAF-related genes. Patients with low-risk scores were found to have higher chemosensitivity to cisplatin, doxorubicin, and sorafenib. Individuals with high-risk scores were found with a higher expression of most immune checkpoints which indicated patients with high-risk scores may benefit more from treatment with immune checkpoint inhibitors. Furthermore, a correlation between immune infiltration characteristics of TME and patients with different risk levels was found. These findings provide a possibility for the further development of personalized treatments in HCC.


Assuntos
Fibroblastos Associados a Câncer , Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Carcinoma Hepatocelular/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Prognóstico , Microambiente Tumoral/genética
16.
Mitochondrial DNA B Resour ; 7(6): 1044-1045, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35756436

RESUMO

For the first time, the complete mitochondrial genome of Parasitus fimetorum was sequenced. The mitochondrial genome is 14,619 bp in length and includes 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a control region. The base composition is 35.6% for A, 34.8% for T, 18.2% for G, and 11.4% for C. A phylogenetic tree based on the maximum likelihood (ML) method indicated that Parasitus fimetorum was clustered with Parasitus wangdunqingi within the family Parasitidae.

17.
Biotechnol Lett ; 44(4): 613-621, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35359178

RESUMO

To study the effect of SpyTag/SpyCatcher cyclization on stability and refolding of protein, we constructed a cyclized green fluorescent protein (SRGFP) and its derivative to act as a linear structure control (L-SRGFP). SRGFP and L-SRGFP showed similar fluorescence characteristics to the wild-type GFP, while compared with GFP and L-SRGFP, the thermal stability and denaturation resistance of SRGFP were improved. The refolding efficiencies of these three denatured proteins were investigated under different pH, temperature and initial protein concentration conditions, and it was found that SRGFP was superior to GFP and L-SRGFP in terms of refolding yield and refolding speed. In the pH range of 8.0-8.5, SRGFP could basically recover all fluorescence, while GFP and L-SRGFP recovered only about 87.52% and 88.58%. When refolded at a high temperature (37 °C), SRGFP still recovered 85.27% of the fluorescence, whereas GFP and L-SRGFP recovered only around 69.43% and 68.45%. At a high initial protein concentration (5 mg/mL), the refolding yield of SRGFP was about 15% higher than that of both GFP and L-SRGFP. These results suggest that the introduction of SpyRing structure (head-to-tail cyclization via SpyTag and SpyCatcher) improved the protein's stability and facilitated the refolding of denatured protein.


Assuntos
Temperatura Alta , Ciclização , Proteínas de Fluorescência Verde/genética , Desnaturação Proteica , Temperatura
18.
Appl Biochem Biotechnol ; 194(8): 3527-3540, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35386065

RESUMO

In this study, nitrilase (Nit) was immobilized in zeolite imidazole framework-90 (ZIF-90) by one-pot biomimetic mineralization strategy. The structure, morphology and functional groups of ZIF-90 and immobilized enzyme Nit@ZIF-90 were characterized by scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). Circular dichroism (CD) proved that the immobilized method of encapsulation in ZIF-90 could effectively maintain the intrinsic conformation of Nit. Meanwhile, the stability and reusability of Nit@ZIF-90 were systematically evaluated. Compared with the free enzyme, the thermal, pH and organic solvents stability of Nit@ZIF-90 were significantly increased. Further, Nit@ZIF-90 exhibited better reusability during the hydrolysis of acrylonitrile and retained 48.34% of the initial activity after 10 cycles. Besides, the Ni@ZIF-90 had preferable storage stability, which showed a high degree of residual activity (more than 64 %) after storage at 4 °C for 7 d. The improved stability and reusability of the Nit@ZIF-90 implied that it could be used as a potential effective biocatalyst for hydrolysis of nitrile compounds in industrial application.


Assuntos
Zeolitas , Aminoidrolases , Enzimas Imobilizadas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Zeolitas/química
19.
Biomed Res Int ; 2022: 1565207, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35141330

RESUMO

BACKGROUND: The dismal prognosis of gastric signet ring cell carcinoma (GSRC) is a global problem. The current study is conducted to comprehensively evaluate clinicopathological features and survival outcomes in GSRC patients stratified by anatomic subsites. Then, predictive nomograms are constructed and validated to improve the effectiveness of personalized management. METHOD: The patients diagnosed with GSRC were recruited from the online SEER database. The influence of anatomic subsites on overall survival (OS) and cancer-specific survival (CSS) was evaluated using multivariate Cox regression and Kaplan-Meier analysis. Then, we employed propensity score matching (PSM) technique to decrease selection bias and balance patients' epidemiological factors. Predictive nomograms were constructed and validated. Sensitivity analysis was performed to validate the conclusion. RESULTS: Multivariate Cox regression demonstrated that the patients with overlapping gastric cancer (OGC) suffered the highest mortality risk for OS (HR, 1.29; 95% CI, 1.23-1.36; P < 0.001) and CSS (HR, 1.33; 95% CI, 1.28-1.37; P < 0.001). Age, TNM stage, tumor localization, tumor size, surgery, and chemotherapy presented a highly significant relationship with OS and CSS. Following subgroup and PSM analysis, OGC patients were confirmed to have the worst OS and CSS. Then, nomograms predicting 6-month, 12-month, and 36-month survival were constructed. The area under the curve (AUC) value in ROC was 0.775 (95% CI, 0.761-0.793) for 6-month survival, 0.789 (95% CI, 0.776-0.801) for 12-month survival, and 0.780 (95% CI, 0.765-0.793) for 36-month survival in the OS group, while in the CSS group, it was 0.771 (95% CI, 0.758-0.790) for 6-month survival, 0.781 (95% CI, 0.770-0.799) for 12-month survival, and 0.773 (95% CI, 0.762-0.790) for 36-month survival. CONCLUSION: We identified anatomic subsites as a predictor of survival in those with GSRC. Patients with OGC suffered the highest mortality risk. The proposed nomograms allowed a relatively accurate survival prediction for GSRC patients.


Assuntos
Carcinoma de Células em Anel de Sinete/patologia , Neoplasias Gástricas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células em Anel de Sinete/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Nomogramas , Prognóstico , Pontuação de Propensão , Programa de SEER , Neoplasias Gástricas/mortalidade , Análise de Sobrevida
20.
Int J Biol Macromol ; 199: 358-371, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35031313

RESUMO

SpyTag/Catcher chemistry is usually applied to engineer robust enzymes via head-to-tail cyclization using spontaneous intramolecular isopeptide bond formation. However, the SpyTag/Catcher induced intercellular protein assembly in vivo cannot be ignored. It was found that some active inclusion bodies had generated to different proportions in the expression of six SpyTag/Catcher labeled proteins (CatIBs-STCProtein). Some factors that may affect the formation of CatIBs-STCProtein were discussed, and the subunit quantities were found to be strongly positively related to the formation of protein aggregates. Approximately 85.44% of the activity of the octameric protein leucine dehydrogenase (LDH) was expressed in aggregates, while the activity of the monomeric protein green fluorescence protein (GFP) in aggregates was 12.51%. The results indicated that SpyTag/Catcher can be used to form protein aggregates in E. coli. To facilitate the advantages of CatIBs-STCProtein, we took the CatIBs-STCLDH as an example and further chemically cross-linked with glutaraldehyde to obtain novel cross-linked enzyme aggregates (CLEAs-CatIBs-STCLDH). CLEAs-CatIBs-STCLDH had good thermal stability and organic solvents stability, and its activity remained 51.03% after incubation at 60 °C for 100 mins. Moreover, the crosslinked CatIBs-STCLDH also showed superior stability over traditional CLEAs, and its activity remained 98.70% after 10 cycles of catalysis.


Assuntos
Escherichia coli , Corpos de Inclusão , Reagentes de Ligações Cruzadas/química , Estabilidade Enzimática , Enzimas Imobilizadas/química , Escherichia coli/genética , Escherichia coli/metabolismo , Glutaral/metabolismo , Agregados Proteicos , Proteínas/metabolismo
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