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1.
Arch Microbiol ; 203(1): 261-268, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32918097

RESUMO

Extremely halophilic archaea (haloarchaea) belonging to the phylum Euryarchaeota have been found in high-salinity environments. In this study, Halarchaeum sp. CBA1220, Halorubrum sp. CBA1229, and Halolamina sp. CBA1230, which are facultatively oligotrophic haloarchaea, were isolated from solar salt by culture under oligotrophic culture conditions. The complete genomes of strains CBA1220, CBA1229, and CBA1230 were sequenced and were found to contain 3,175,875, 3,582,278, and 3,465,332 bp, with a G + C content of 68.25, 67.66, and 66.75 mol %, respectively. In total, 60, 36, and 33 carbohydrate-active enzyme genes were determined in the respective strains. The strains harbored various genes encoding stress-tolerance proteins, including universal stress proteins, cold-shock proteins, and rubrerythrin and rubrerythrin-related proteins. The genome data produced in this study will facilitate further research to improve our understanding of other halophilic strains and promote their industrial application.


Assuntos
Euryarchaeota/genética , Genoma Arqueal/genética , Composição de Bases , Genômica , Halobacteriaceae/classificação , Halobacteriaceae/genética , Halorubrum/classificação , Halorubrum/genética , Salinidade , Estresse Fisiológico/genética
2.
Int J Syst Evol Microbiol ; 70(7): 4298-4304, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32589569

RESUMO

A novel, facultatively anaerobic actinobacterium, designated strain CBA3103T, was isolated from sediment of the Geum River in South Korea. Phylogenetic analysis indicated that strain CBA3103T is most closely related to Raineyella antarctica LZ-22T (98.47 % 16S rRNA gene sequence similarity). The genome of strain CBA3103T was 3 649 865 bp with a DNA G+C content of 69.6 mol%. The average nucleotide identity value between strain CBA3103T and R. antarctica LZ-22T was 79.22 %. Cells of strain CBA3103T were Gram-positive, rod-shaped, 0.6-0.9 µm wide and 1.4-2.4 µm long. Growth occurred at 15-40 °C (optimum, 35 °C), at pH 6.0-7.0 (optimum, pH 7.0) and with 0-2 % NaCl (w/v) (optimum, 0-1 %, w/v). The major cellular fatty acids in strain CBA3103T were anteiso-C15 : 0, anteiso-C15 : 1 A and iso-C14 : 0. The major respiratory quinone was menaquinone-9(H4). The polar lipids of strain CBA3103T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, five unidentified glycolipids and three unidentified phospholipids. Based on the genotypic, phenotypic and chemotaxonomic analyses, strain CBA3103T represents a novel species of the genus Raineyella, for which the name Raineyella fluvialis sp. nov. (type strain CBA3103T=KACC 21446T=DSM 110288T) is proposed.


Assuntos
Sedimentos Geológicos , Filogenia , Propionibacteriaceae/classificação , Rios/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
3.
Biomacromolecules ; 18(12): 4113-4120, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-28949131

RESUMO

The anticoagulant activity of heparin administered during medical interventions must be reversed to restore normal clotting, typically by titrating with protamine. Given the acute toxicity associated with protamine, we endeavored to generate safer heparin antagonists by engineering bacteriophage Qß virus-like particles (VLPs) to display motifs that bind heparin. A particle bearing a single amino acid change from wild-type (T18R) was identified as a promising candidate for heparin antagonism. Surface potential maps generated through molecular modeling reveal that the T18R mutation adds synergistically to adjacent positive charges on the particle surface, resulting in a large solvent-accessible cationic region that is replicated 180 times over the capsid. Chromatography using a heparin-sepharose column confirmed a strong interaction between heparin and the T18R particle. Binding studies using fluorescein-labeled heparin (HepFL) resulted in a concentration-dependent change in fluorescence intensity, which could be perturbed by the addition of unlabeled heparin. Analysis of the fluorescence data yielded a dissociation constant of approximately 1 nM and a 1:1 binding stoichiometry for HepFL:VLP. Dynamic light scattering (DLS) experiments suggested that T18R forms discrete complexes with heparin when the VLP:heparin molar ratios are equivalent, and in vitro clotting assays confirmed the 1:1 binding stoichiometry as full antagonism of heparin is achieved. Biolayer interferometry and backscattering interferometry corroborated the strong interaction of T18R with heparin, yielding Kd ∼ 1-10 nM. These biophysical measurements further validated T18R, and VLPs in general, for potential clinical use as effective, nontoxic heparin antagonists.


Assuntos
Allolevivirus/química , Antagonistas de Heparina/química , Heparina/química , Nanopartículas/química , Anticoagulantes/química , Sítios de Ligação , Capsídeo/química , Proteínas do Capsídeo/química , Cátions/química , Fluorescência , Protaminas/química , Ligação Proteica
4.
Proc Natl Acad Sci U S A ; 111(34): 12556-61, 2014 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25114221

RESUMO

In a fluorescence polarization screen for the MYC-MAX interaction, we have identified a novel small-molecule inhibitor of MYC, KJ-Pyr-9, from a Kröhnke pyridine library. The Kd of KJ-Pyr-9 for MYC in vitro is 6.5 ± 1.0 nM, as determined by backscattering interferometry; KJ-Pyr-9 also interferes with MYC-MAX complex formation in the cell, as shown in a protein fragment complementation assay. KJ-Pyr-9 specifically inhibits MYC-induced oncogenic transformation in cell culture; it has no or only weak effects on the oncogenic activity of several unrelated oncoproteins. KJ-Pyr-9 preferentially interferes with the proliferation of MYC-overexpressing human and avian cells and specifically reduces the MYC-driven transcriptional signature. In vivo, KJ-Pyr-9 effectively blocks the growth of a xenotransplant of MYC-amplified human cancer cells.


Assuntos
Antineoplásicos/farmacologia , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Piridinas/farmacologia , Pirimidinas/farmacologia , Animais , Antineoplásicos/química , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/antagonistas & inibidores , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/química , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Células Cultivadas , Embrião de Galinha , Avaliação Pré-Clínica de Medicamentos , Feminino , Polarização de Fluorescência , Genes myc , Humanos , Interferometria , Camundongos , Camundongos Nus , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/química , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/química , Piridinas/química , Pirimidinas/química , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Molecules ; 22(10)2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28981451

RESUMO

Glycol chitosan (GC) and its derivatives have been extensively investigated as safe and effective drug delivery carriers because of their unique physiochemical and biological properties. The reactive functional groups such as the amine and hydroxyl groups on the GC backbone allow for easy chemical modification with various chemical compounds (e.g., hydrophobic molecules, crosslinkers, and acid-sensitive and labile molecules), and the versatility in chemical modifications enables production of a wide range of GC-based drug carriers. This review summarizes the versatile chemical modification methods that can be used to design GC-based drug carriers and describes their recent applications in disease therapy.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Nanopartículas/química , Animais , Antineoplásicos/administração & dosagem , Reagentes de Ligações Cruzadas/química , Terapia Genética/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Fotoquimioterapia/métodos
6.
Int J Syst Evol Microbiol ; 66(7): 2740-2746, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27118259

RESUMO

A novel halophilic archaeon designated strain CBA1114T was isolated from solar salt in the Republic of Korea. Strain CBA1114T, cells of which were coccoid and Gram-stain-negative, grew in the presence of 15-30 % (w/v) NaCl (optimum, 20 %) and at 20-50 °C (optimum, 40 °C) and pH 7.0-9.0 (optimum, pH 8.0). Strain CBA1114T required Mg2+ for growth. Strain CBA1114T had three 16S rRNA genes, rrnA, rrnB and rrnC; levels of similarity between the sequences were 99.7-99.9 %. The 16S rRNA gene sequence of strain CBA1114T showed 91.7 % similarity to that of Haloterrigena thermotolerans PR5T. In multilocus sequence analysis (MLSA), five housekeeping genes, atpB, EF-2, radA, rpoB' and secY, were found to be closely related to those of the members of the genera Halorientalis(89.7 % similarity of the atpB gene sequence), Halomicroarcula(91.9 %, EF-2), Haloterrigena(85.4 %, radA), Natronoarchaeum(89.2 %, rpoB') and Natrinema(75.7 %, secY). A phylogenetic tree generated from the results of MLSA of the five housekeeping genes showed that strain CBA1114T was closely related to species of the genus Halorientalis in the family Halobacteriaceae. The major polar lipids were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and unidentified lipids. The G+C content of the genomic DNA of strain CBA1114T was 68.1 mol%. According to the results of phylogenetic, phenotypic and chemotaxonomic analyses, we designate strain CBA1114T (=JCM 30111T=KCTC 4206T) as the type strain of Halostella salina gen. nov., sp. nov., a novel species of a new genus within the family Halobacteriaceae.


Assuntos
Halobacteriaceae/classificação , Filogenia , Cloreto de Sódio , Composição de Bases , DNA Arqueal/genética , Genes Arqueais , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Tipagem de Sequências Multilocus , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
7.
Nanomedicine ; 12(6): 1489-98, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27013134

RESUMO

Host-targeting antivirals have an advantage over direct-acting antivirals in that they have a high genetic barrier to resistance. Here, we describe in vivo anti-hepatitis C virus (HCV) efficacy of a potent siRNA targeting the protein kinase C-related kinase 2 (PRK2), which phosphorylates HCV NS5B RNA-dependent RNA polymerase and promotes HCV replication. PRK2-silencing reduced the phosphorylated NS5B level and resulted in inhibition of NS5B RdRp activity to decrease HCV genome abundance. Systemic administration of lipidoid nanoparticle-formulated PRK2 siRNA (once every three days for a total of three injections at a dose of 3mgkg(-1)) resulted in a 3.72 and 1.96 log10 reduction in serum HCV RNA titer, in mouse subcutaneous and orthotopic xenograft models for HCV replication, respectively. Our results verify the essential role of PRK2 in HCV replication and offer a host-targeting anti-HCV siRNA therapy that might be beneficial for non-responders to current treatment regimens.


Assuntos
Antivirais/administração & dosagem , Hepacivirus , Nanopartículas , RNA Interferente Pequeno/administração & dosagem , Animais , Camundongos , Proteínas não Estruturais Virais , Replicação Viral
8.
Angew Chem Int Ed Engl ; 55(8): 2688-92, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26799917

RESUMO

The membrane-proximal external region (MPER) of HIV gp41 is an established target of antibodies that neutralize a broad range of HIV isolates. To evaluate the role of the transmembrane (TM) domain, synthetic MPER-derived peptides were incorporated into lipid nanoparticles using natural and designed TM domains, and antibody affinity was measured using immobilized and solution-based techniques. Peptides incorporating the native HIV TM domain exhibit significantly stronger interactions with neutralizing antibodies than peptides with a monomeric TM domain. Furthermore, a peptide with a trimeric, three-helix bundle TM domain recapitulates the binding profile of the native sequence. These studies suggest that neutralizing antibodies can bind the MPER when the TM domain is a three-helix bundle and this presentation could influence the binding of neutralizing antibodies to the virus. Lipid-bilayer presentation of viral antigens in Nanodiscs is a new platform for evaluating neutralizing antibodies.


Assuntos
Anticorpos Neutralizantes/imunologia , Biopolímeros/química , Proteína gp41 do Envelope de HIV/química , Bicamadas Lipídicas , Ensaio de Imunoadsorção Enzimática , Proteína gp41 do Envelope de HIV/imunologia
9.
J Virol ; 88(19): 11240-52, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25031343

RESUMO

UNLABELLED: Hepatitis C virus (HCV) nonstructural protein 5B (NS5B), an RNA-dependent RNA polymerase (RdRp), is the key enzyme for HCV RNA replication. We previously showed that HCV RdRp is phosphorylated by protein kinase C-related kinase 2 (PRK2). In the present study, we used biochemical and reverse-genetics approaches to demonstrate that HCV NS5B phosphorylation is crucial for viral RNA replication in cell culture. Two-dimensional phosphoamino acid analysis revealed that PRK2 phosphorylates NS5B exclusively at its serine residues in vitro and in vivo. Using in vitro kinase assays and mass spectrometry, we identified two phosphorylation sites, Ser29 and Ser42, in the Δ1 finger loop region that interacts with the thumb subdomain of NS5B. Colony-forming assays using drug-selectable HCV subgenomic RNA replicons revealed that preventing phosphorylation by Ala substitution at either Ser29 or Ser42 impairs HCV RNA replication. Furthermore, reverse-genetics studies using HCV infectious clones encoding phosphorylation-defective NS5B confirmed the crucial role of these PRK2 phosphorylation sites in viral RNA replication. Molecular-modeling studies predicted that the phosphorylation of NS5B stabilizes the interactions between its Δ1 loop and thumb subdomain, which are required for the formation of the closed conformation of NS5B known to be important for de novo RNA synthesis. Collectively, our results provide evidence that HCV NS5B phosphorylation has a positive regulatory role in HCV RNA replication. IMPORTANCE: While the role of RNA-dependent RNA polymerases (RdRps) in viral RNA replication is clear, little is known about their functional regulation by phosphorylation. In this study, we addressed several important questions about the function and structure of phosphorylated hepatitis C virus (HCV) nonstructural protein 5B (NS5B). Reverse-genetics studies with HCV replicons encoding phosphorylation-defective NS5B mutants and analysis of their RdRp activities revealed previously unidentified NS5B protein features related to HCV replication and NS5B phosphorylation. These attributes most likely reflect potential structural changes induced by phosphorylation in the Δ1 finger loop region of NS5B with two identified phosphate acceptor sites, Ser29 and Ser42, which may transiently affect the closed conformation of NS5B. Elucidating the effects of dynamic changes in NS5B phosphorylation status during viral replication and their impacts on RNA synthesis will improve our understanding of the molecular mechanisms of NS5B phosphorylation-mediated regulation of HCV replication.


Assuntos
Regulação Viral da Expressão Gênica , Hepacivirus/genética , Proteína Quinase C/genética , RNA Polimerase Dependente de RNA/genética , Serina/metabolismo , Proteínas não Estruturais Virais/genética , Replicação Viral , Sequência de Aminoácidos , Linhagem Celular Tumoral , Hepacivirus/metabolismo , Hepatócitos/metabolismo , Hepatócitos/virologia , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Fosforilação , Proteína Quinase C/metabolismo , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina/genética , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
10.
Int J Syst Evol Microbiol ; 65(Pt 1): 201-205, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25323594

RESUMO

An anaerobic, rod-shaped, hyperthermophilic and acidophilic crenarchaeon, designated strain CBA1501(T), was isolated from solfataric soil of the Mayon volcano in the Republic of the Philippines. Phylogenetic analysis showed that strain CBA1501(T) is affiliated with the genus Vulcanisaeta in the phylum Crenarchaeota. DNA sequence similarities between the 16S rRNA gene of strain CBA1501(T) and those of Vulcanisaeta distributa IC-017(T) and Vulcanisaeta souniana IC-059(T) were 98.5 and 97.4 %, respectively. Strain CBA1501(T) grew between 75-90 °C, over a pH range of 4.0-6.0 and in the presence of 0-1.0 % (w/v) NaCl, with optimal growth occurring at 85 °C, pH 5.0, and with 0 % (w/v) NaCl. Fumarate, malate, oxidized glutathione, sulfur and thiosulfate were used as final electron acceptors, but FeCl3, nitrate and sulfate were not. The DNA G+C content of strain CBA1501(T) was 43.1 mol%. On the basis of polyphasic taxonomic analysis, strain CBA1501(T) represents a novel species of the genus Vulcanisaeta in the phylum Crenarchaeota, for which we propose the name Vulcanisaeta thermophila sp. nov. The type strain is CBA1501(T) ( = ATCC BAA-2415(T) = JCM 17228(T)).


Assuntos
Crenarchaeota/classificação , Filogenia , Microbiologia do Solo , Composição de Bases , Crenarchaeota/genética , Crenarchaeota/isolamento & purificação , DNA Arqueal/genética , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filipinas , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Antonie Van Leeuwenhoek ; 105(5): 925-32, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24609529

RESUMO

A halophilic archaeon, designed strain CBA1103(T), was isolated from non-purified solar salt. The cells of strain CBA1103(T) were observed to be Gram-stain negative and pleomorphic, and the colonies appear red. Strain CBA1103(T) was observed to grow between 20 and 55 °C (optimum 37 °C), and in NaCl concentrations of 10-30 % (w/v) (optimum 15 %) with 0-0.5 M MgSO4·7H2O (optimum 0.1 M) and at pH 6.0-9.0 (optimum pH 7.0). Additionally, the cells lyse in distilled water. The major polar lipids of strain CBA1103(T) are phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and two glycolipids chromatographically identical to sulfated mannosyl glucosyl diether and manosyl glucosyl diether. Strain CBA1103(T) is shown to belong to the Halobellus genus and exhibits similarity to related taxa; the 16S rRNA gene sequence similarity between strain CBA1103(T) and Halobellus rarus 18362(T), Hbs. limi 16811(T), Hbs. litoreus JCM 17118(T), Hbs. inordinatus YC20(T), Hbs. clavatus TNN18(T) and Hbs. salinus CSW2.24.4(T) is 97.3, 96.5, 96.5, 94.5, 94.5 and 93.7 %, respectively. The RNA polymerase subunit B gene sequence of strain CBA1103(T) shows 93.7 % similarity with the sequence of Hbs. litoreus JCM 17118(T); the similarity is lower with sequences from the type strains of other species of Halobellus. The genomic DNA G+C content of strain CBA1103(T) was determined to be 67.0 mol% a value which is in the range of the genomic DNA G+C content of members of the genus Halobellus (61.5-69.2 mol%). These results suggest that strain CBA1103(T) should be considered to represent a new taxon for which the name Halobellus rufus sp. nov. is proposed, with the type strain CBA1103(T) (=CECT 8423(T) =JCM 19434(T)).


Assuntos
Microbiologia Ambiental , Halobacteriaceae/classificação , Halobacteriaceae/isolamento & purificação , Sais/metabolismo , Proteínas Arqueais/genética , Análise por Conglomerados , DNA Arqueal/química , DNA Arqueal/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Polimerases Dirigidas por DNA/genética , Glicolipídeos/análise , Halobacteriaceae/genética , Halobacteriaceae/metabolismo , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética
12.
Antonie Van Leeuwenhoek ; 105(5): 979-86, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24677144

RESUMO

A halophilic archaeal strain, designated CBA1105(T), was isolated from non-purified solar salt. Strain CBA1105(T) was found to have three 16S rRNA genes, rrnA, rrnB and rrnC; similarities between the 16S rRNA gene sequences were 99.5-99.7 %. The phylogenetic analysis of the 16S rRNA gene sequences showed that strain CBA1105(T) forms a distinct clade with the strains of the closely related genera, Halorientalis and Halorhabdus, with similarities of 94.2 % and 93.9-94.2 %, respectively. Multilocus sequence analysis confirmed that strain CBA1105(T) is closely related to the genus Halorhabdus or Halorientalis. Growth of the strain was observed in 15-30 % NaCl (w/v; optimum 20 %), at 30-45 °C (optimum 37 °C) and pH 7.0-8.0 (optimum pH 7.0) and with 0-0.5 M MgCl2·6H2O (optimum 0.05-0.2 M). The cells of the strain were observed to be Gram-stain negative and pleomorphic with coccoid or ovoid-shape. The cells lysed in distilled water. Tweens 20, 40 and 80 were found to be hydrolysed but starch, casein and gelatine were not. The cells were unable to reduce nitrate under aerobic conditions. Assays for indole formation and urease activity were negative and no growth was observed under anaerobic conditions. Cells were found to be able to utilize L-glutamate, D-glucose, L-maltose, D-mannose and sucrose as sole carbon sources. The polar lipids were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, unidentified glycolipids and an unidentified phospholipid. The G+C content of strain CBA1105(T) was determined to be 66.0 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that the strain represents a novel species of a novel genus within the family Halobacteriaceae, for which the name Halapricum salinum is proposed with CBA1105(T) (= KCTC 4202(T) = JCM 19729(T)) as the type strain.


Assuntos
Microbiologia Ambiental , Halobacteriaceae/classificação , Halobacteriaceae/isolamento & purificação , Sais/metabolismo , Proteínas Arqueais/genética , Análise por Conglomerados , DNA Arqueal/química , DNA Arqueal/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Halobacteriaceae/genética , Halobacteriaceae/metabolismo , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , RNA Ribossômico 16S/genética
13.
Mar Drugs ; 12(12): 6038-57, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25522316

RESUMO

Theranostics is an integrated nanosystem that combines therapeutics with diagnostics in attempt to develop new personalized treatments with enhanced therapeutic efficacy and safety. As a promising therapeutic paradigm with cutting-edge technologies, theranostic agents are able to simultaneously deliver therapeutic drugs and diagnostic imaging agents and also monitor the response to therapy. Polymeric nanosystems have been intensively explored for biomedical applications to diagnose and treat various cancers. In recent years, glycol chitosan-based nanoagents have been developed as dual-purpose materials for simultaneous diagnosis and therapy. They have shown great potential in cancer therapies, such as chemotherapeutics and nucleic acid and photodynamic therapies. In this review, we summarize the recent progress and potential applications of glycol chitosan-based fluorescent theranostic nanoagents for cancer treatments and discuss their possible underlying mechanisms.


Assuntos
Quitosana/farmacologia , Quitosana/uso terapêutico , Corantes Fluorescentes/farmacologia , Corantes Fluorescentes/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Diagnóstico por Imagem/métodos , Humanos
14.
J Microbiol Biotechnol ; 34(4): 891-901, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38379303

RESUMO

This study focuses on improving the 3D printability of pea protein with the help of food inks designed for jet-type 3D printers. Initially, the food ink base was formulated using nanocellulose-alginate with a gradient of native potato starch and its 3D printability was evaluated. The 3D-printed structures using only candidates for the food ink base formulated with or without potato starch exhibited dimensional accuracy exceeding 95% on both the X and Y axes. However, the accuracy of stacking on the Z-axis was significantly affected by the ink composition. Food ink with 1% potato starch closely matched the CAD design, with an accuracy of approximately 99% on the Z-axis. Potato starch enhanced the stacking of 3D-printed structures by improving the electrostatic repulsion, viscoelasticity, and thixotropic behavior of the food ink base. The 3D printability of pea protein was evaluated using the selected food ink base, showing a 46% improvement in dimensional accuracy on the Z-axis compared to the control group printed with a food ink base lacking potato starch. These findings suggest that starch can serve as an additive support for high-resolution 3D jet-type printing of food ink material.


Assuntos
Tinta , Impressão Tridimensional , Solanum tuberosum , Amido , Solanum tuberosum/química , Amido/química , Proteínas de Ervilha/química , Alginatos/química , Celulose/química , Viscosidade
15.
J Antimicrob Chemother ; 67(1): 49-58, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22076990

RESUMO

OBJECTIVES: Hepatitis C virus (HCV) infection causes chronic liver disease and is a major public health problem worldwide. The aim of this study was to evaluate the potential of Monascus pigment derivatives, which were derived from a microbial secondary metabolite synthesized from polyketides by Monascus spp., as HCV antiviral agents. METHODS: We performed an in vitro RNA-dependent RNA polymerase (RdRp) assay to screen for HCV RdRp inhibitors. The anti-HCV activity of RdRp inhibitors in HCV-replicating cells was evaluated by quantification of the RNA viral genome. Molecular docking analysis was performed to predict the binding sites of the selected RdRp inhibitors. RESULTS: We have identified a Monascus pigment and its derivatives as inhibitors of the HCV NS5B RdRp. A group of Monascus orange pigment (MOP) amino acid derivatives, in which the reactive oxygen moiety was changed to amino acids, significantly inhibited HCV replication. Further, combination of the MOP derivatives (Phe, Val or Leu conjugates) with interferon (IFN)-α inhibited HCV replication more than IFN-α treatment alone. Lastly, molecular docking studies indicate the inhibitors may bind to a thumb subdomain allosteric site of NS5B. The antiviral activity of the MOP derivatives was related to a modulation of the mevalonate pathway, since the mevalonate-induced increase in HCV replication was suppressed by the MOP compounds. CONCLUSIONS: Our results identify amino acid derivatives of MOP as potential anti-HCV agents and suggest that their combination with IFN-α might offer an alternative strategy for the control of HCV replication.


Assuntos
Antivirais/farmacologia , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Hepacivirus/efeitos dos fármacos , Ácido Mevalônico/metabolismo , Monascus/química , Pigmentos Biológicos/farmacologia , Replicação Viral/efeitos dos fármacos , Antivirais/química , Antivirais/isolamento & purificação , Sítios de Ligação , Vias Biossintéticas/genética , RNA Polimerases Dirigidas por DNA/química , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Simulação de Dinâmica Molecular , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação
16.
Biomacromolecules ; 13(8): 2333-8, 2012 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-22827531

RESUMO

Virus-like particles (VLPs) have proven to be versatile platforms for chemical and genetic functionalization for a variety of purposes in biomedicine, catalysis, and materials science. We describe here the simultaneous modification of the bacteriophage Qß VLP with a metalloporphyrin derivative for photodynamic therapy and a glycan ligand for specific targeting of cells bearing the CD22 receptor. This application benefits from the presence of the targeting function and the delivery of a high local concentration of singlet oxygen-generating payload.


Assuntos
Allolevivirus/química , Nanocápsulas/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Polissacarídeos/metabolismo , Porfirinas/química , Allolevivirus/metabolismo , Animais , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Química Click , Cricetinae , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/metabolismo , Humanos , Concentração Inibidora 50 , Nanopartículas , Tamanho da Partícula , Fármacos Fotossensibilizantes/farmacologia , Polissacarídeos/química , Porfirinas/farmacologia , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Ácidos Siálicos/química , Ácidos Siálicos/metabolismo , Oxigênio Singlete
17.
J Microbiol Biotechnol ; 32(12): 1573-1582, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36398443

RESUMO

In this study, we investigated the optimal conditions for 3D structure printing of alternative fats that have the textural properties of lard using beeswax (BW)-based oleogel by a statistical analysis. Products printed with over 15% BW oleogel at 50% and 75% infill level (IL) showed high printing accuracy with the lowest dimensional printing deviation for the designed model. The hardness, cohesion, and adhesion of printed samples were influenced by BW concentration and infill level. For multi-response optimization, fixed target values (hardness, adhesiveness, and cohesiveness) were applied with lard printed at 75% IL. The preparation parameters obtained as a result of multiple reaction prediction were 58.9% IL and 16.0% BW, and printing with this oleogel achieved fixed target values similar to those of lard. In conclusion, our study shows that 3D printing based on the BW oleogel system produces complex internal structures that allow adjustment of the textural properties of the printed samples, and BW oleogels could potentially serve as an excellent replacement for fat.


Assuntos
Impressão Tridimensional , Ceras , Ceras/química
18.
Biomacromolecules ; 12(11): 3977-81, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21995513

RESUMO

Qß virus-like particles encapsulating multiple copies of fluorescent proteins were generated in high yields using a modular system enhanced by specific engineered RNA--protein interactions. The resulting particles were structurally indistinguishable from recombinant Qß alone. The encapsidated proteins were nearly identical in photochemical properties to monomeric analogues, were more stable toward thermal degradation, and were protected from proteolytic cleavage. Residues on the outer capsid surface were chemically derivatized by acylation and azide--alkyne cycloaddition without affecting the fluorescence properties of the packaged proteins. A high-affinity carbohydrate-based ligand of the CD22 receptor was thereby attached, and specific cell labeling by the particles was successfully detected by flow cytometry and confocal laser microscopy.


Assuntos
Allolevivirus , Proteínas do Capsídeo/metabolismo , Capsídeo/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas Luminescentes/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Animais , Aptâmeros de Nucleotídeos/metabolismo , Células CHO , Clonagem Molecular , Cricetinae , Humanos , Estabilidade Proteica , Proteínas Recombinantes de Fusão/isolamento & purificação , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Ligação Viral
19.
Food Res Int ; 149: 110668, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600670

RESUMO

Kimchi is a fermented food prepared via spontaneous fermentation by lactic acid bacteria originating from raw ingredients. To investigate the effect of these ingredients on food fermentation, four types of food that differed only in their main raw ingredients (kimchi cabbage, green onion, leaf mustard, and young radish) were evaluated. The major microorganisms were Leuconostoc gelidum, Weissella kandleri, and Lactobacillus sakei groups. The distribution of these species depended on the sample type. All three species were primarily distributed in the food prepared from kimchi cabbage and young radish; however, the Lac. sakei group was hardly found in the food prepared using green onion and leaf mustard. Metabolite analysis results showed that the free sugar, organic acid, ethanol, and amino acid profiles differed with the sample type. This study indicates that the main ingredients could be an important factor in determining the composition of the microbial community and the metabolite composition.


Assuntos
Alimentos Fermentados , Microbiologia de Alimentos , Fermentação , Leuconostoc , Weissella
20.
J Microbiol Biotechnol ; 30(11): 1706-1719, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-32830188

RESUMO

The objective of this study was to optimize the conditions for enhancing the antioxidant properties of sword bean (Canavalia gladiata) as a coffee substitute in two processing methods, roasting and grinding. The optimum conditions for removing off-flavor of the bean and maximizing functionality and efficiency were light roasting and cryogenic grinding (< 53 µm). In these conditions, extraction yield was 16.75%, total phenolic content (TPC) was 69.82 ± 0.35 mg gallic acid equivalents/g, and total flavonoid content (TFC) was 168.81 ± 1.64 mg quercetin equivalents/100 g. The antioxidant properties were 77.58 ± 0.27% for DPPH radical scavenging activity and 58.02 ± 0.76 mg Trolox equivalents/g for ABTS radical scavenging activity. The values for TFC and ABTS radical scavenging activity were significantly higher (p < 0.05) than in other conditions, and TPC and DPPH radical scavenging activity were second highest in lightly roasted beans, following raw beans. HS-SPME/GCMS analysis confirmed that the amino acids and carbohydrates, which are the main components of sword bean, were condensed into other volatile flavor compounds, such as derivatives of furan, pyrazine, and pyrrole during roasting. Roasted and cryogenically ground (cryo-ground) sword beans showed higher functionality in terms of TFC, DPPH, and ABTS radical scavenging activities compared to those of coffee. Overall results showed that light roasting and cryogenic grinding are the most suitable processing conditions for enhancing the bioactivity of sword beans.


Assuntos
Antioxidantes/análise , Canavalia/química , Extratos Vegetais/química , Café/química , Flavonoides/análise , Manipulação de Alimentos/métodos , Ácido Gálico , Temperatura Alta , Tamanho da Partícula , Fenóis/análise , Sementes/química
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