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1.
Molecules ; 27(12)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35745070

RESUMO

Our previous findings have shown that the chlorophyllides composites have anticancer activities to breast cancer cell lines (MCF-7 and MDA-MB-231). In the present study, microarray gene expression profiling was utilized to investigate the chlorophyllides anticancer mechanism on the breast cancer cells lines. Results showed that chlorophyllides composites induced upregulation of 43 and 56 differentially expressed genes (DEG) in MCF-7 and MDA-MB-231 cells, respectively. In both cell lines, chlorophyllides composites modulated the expression of annexin A4 (ANXA4), chemokine C-C motif receptor 1 (CCR1), stromal interaction molecule 2 (STIM2), ethanolamine kinase 1 (ETNK1) and member of RAS oncogene family (RAP2B). Further, the KEGG annotation revealed that chlorophyllides composites modulated DEGs that are associated with the endocrine system in MCF-7 cells and with the nervous system in MDA-MB-231 cells, respectively. The expression levels of 9 genes were validated by quantitative reverse transcription PCR (RT-qPCR). The expression of CCR1, STIM2, ETNK1, MAGl1 and TOP2A were upregulated in both chlorophyllides composites treated-MCF-7 and MDA-MB-231 cells. The different expression of NLRC5, SLC7A7 and PKN1 provided valuable information for future investigation and development of novel cancer therapy.


Assuntos
Neoplasias da Mama , Clorofilídeos , Sistema y+L de Transporte de Aminoácidos , Mama , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Detecção Precoce de Câncer , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Células MCF-7 , Proteínas rap de Ligação ao GTP
2.
Molecules ; 26(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673610

RESUMO

Generally, bacteriochlorophyllides were responsible for the photosynthesis in bacteria. Seven types of bacteriochlorophyllides have been disclosed. Bacteriochlorophyllides a/b/g could be synthesized from divinyl chlorophyllide a. The other bacteriochlorophyllides c/d/e/f could be synthesized from chlorophyllide a. The chemical structure and synthetic route of bacteriochlorophyllides were summarized in this review. Furthermore, the potential applications of bacteriochlorophyllides in photosensitizers, immunosensors, influence on bacteriochlorophyll aggregation, dye-sensitized solar cell, heme synthesis and for light energy harvesting simulation were discussed.


Assuntos
Bactérias/metabolismo , Clorofilídeos/biossíntese , Clorofilídeos/química , Complexos de Coordenação/química , Técnicas Biossensoriais , Vias Biossintéticas , Heme/química , Heme/metabolismo , Fármacos Fotossensibilizantes/química , Fotossíntese , Energia Solar
3.
Plant Mol Biol ; 95(1-2): 181-197, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28840447

RESUMO

KEY MESSAGE: In this present study, we introduce a fundamental framework and provide information regarding the possible roles of GDSL-type esterase/lipase gene family in Arabidopsis. GDSL-type esterases/lipases are hydrolytic enzymes with multifunctional properties such as broad substrate specificity, regiospecificity, and stereoselectivity. In this study, we identified 105 GDSL-type esterase/lipase genes in Arabidopsis thaliana by conducting a comprehensive computational analysis. Expression studies indicated that GDSL-type lipase proteins showed varied expression patterns. Phylogenetic tree analysis indicated that AtGELP (Arabidopsis thaliana GDSL-type esterase/lipase protein) gene family was divided into four clades. The phylogenetic analysis, combined with protein motif architectures, and expression profiling were used to predict the roles AtGELP genes. To investigate the physical roles of the AtGELP gene family, we successfully screened 88 AtGELP T-DNA knockout lines for 54 AtGELP genes from 199 putative SALK T-DNA mutants. Transgenic plants of AtGELP genes were used to elucidate the phenotypic characteristics in various developmental stages or stress conditions. Our results suggest that the AtGELP genes have diverse physical functions such as affecting the germination rate and early growth of seedlings subjected to high concentrations of glucose, or being involved in biotic stress responses.


Assuntos
Arabidopsis/enzimologia , Arabidopsis/genética , Esterases/genética , Genoma de Planta , Lipase/genética , Arabidopsis/crescimento & desenvolvimento , Cromossomos de Plantas/genética , DNA Bacteriano/genética , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Genes de Plantas , Mutagênese Insercional/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Filogenia , Duplicações Segmentares Genômicas , Alinhamento de Sequência
4.
Proc Natl Acad Sci U S A ; 111(44): E4743-52, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25336756

RESUMO

Antrodia cinnamomea, a polyporus mushroom of Taiwan, has long been used as a remedy for cancer, hypertension, and hangover, with an annual market of over $100 million (US) in Taiwan. We obtained a 32.15-Mb genome draft containing 9,254 genes. Genome ontology enrichment and pathway analyses shed light on sexual development and the biosynthesis of sesquiterpenoids, triterpenoids, ergostanes, antroquinonol, and antrocamphin. We identified genes differentially expressed between mycelium and fruiting body and 242 proteins in the mevalonate pathway, terpenoid pathways, cytochrome P450s, and polyketide synthases, which may contribute to the production of medicinal secondary metabolites. Genes of secondary metabolite biosynthetic pathways showed expression enrichment for tissue-specific compounds, including 14-α-demethylase (CYP51F1) in fruiting body for converting lanostane to ergostane triterpenoids, coenzymes Q (COQ) for antroquinonol biosynthesis in mycelium, and polyketide synthase for antrocamphin biosynthesis in fruiting body. Our data will be useful for developing a strategy to increase the production of useful metabolites.


Assuntos
Antrodia/metabolismo , Carpóforos/metabolismo , Proteínas Fúngicas/metabolismo , Micélio/metabolismo , Esterol 14-Desmetilase/metabolismo , Transcriptoma/fisiologia , Antrodia/genética , Carpóforos/genética , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica , Genômica , Humanos , Micélio/genética , Esterol 14-Desmetilase/genética , Taiwan
5.
Biotechnol Appl Biochem ; 63(3): 371-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25828734

RESUMO

Bacteriopheophorbide a (BPheid a) is used as a precursor for bacteriochlorin a (BCA), which can be used for photodynamic therapy in both in vitro and in vivo biochemical applications. This study successfully isolated and expressed a photosynthetic bacterium (Cyanothece sp. ATCC 51142) chlorophyllase called CyanoCLH, which can be used as a biocatalyst for the production of a BCA precursor by degrading bacteriochlorophyll a (BChl a). Substrate specificity and enzyme kinetic analyses were performed and the results verified that the recombinant CyanoCLH preferred hydrolyzing BChl a to produce bacteriochlorophyllide a (BChlide a), which can be converted to BPheid a by removing magnesium ion. The recombinant CyanoCLH was cloned and expressed in Escherichia coli BL-21 (DE3), and its molecular weight was 54.7 kDa. The deduced amino acid sequence of the recombinant CyanoCLH comprised a unique lipase-motif GHSLG, which differs from the GHSRG sequence of other plants and lacks a histidine of the typical and conserved catalytic triad Ser-Asp-His. The recombinant CyanoCLH was subjected to biochemical analyses, and the results indicated that its optimal pH and temperature were 7.0 and 60 °C, respectively.


Assuntos
Bacterioclorofila A/biossíntese , Hidrolases de Éster Carboxílico/metabolismo , Cyanothece/enzimologia , Proteínas Recombinantes/metabolismo , Sequência de Aminoácidos , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/genética , Clonagem Molecular , Cyanothece/genética , Cinética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Especificidade por Substrato
6.
Molecules ; 21(8)2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27472309

RESUMO

Recombinant Chlamydomonas reinhardtii chlorophyllase 1 (CrCLH1) that could catalyze chlorophyll hydrolysis to chlorophyllide and phytol in vitro was successfully expressed in Escherichia coli. The recombinant CrCLH1 was immobilized through covalent binding with a cubic (3-aminopropyl) triethoxysilane (APTES) coating on magnetic iron oxide nanoparticles (MIONPs), which led to markedly improved enzyme performance and decreased biocatalyst costs for potential industrial application. The immobilized enzyme exhibited a high immobilization yield (98.99 ± 0.91 mg/g of gel) and a chlorophyllase assay confirmed that the immobilized recombinant CrCLH1 retained enzymatic activity (722.3 ± 50.3 U/g of gel). Biochemical analysis of the immobilized enzyme, compared with the free enzyme, showed higher optimal pH and pH stability for chlorophyll-a hydrolysis in an acidic environment (pH 3-5). In addition, compared with the free enzyme, the immobilized enzyme showed higher activity in chlorophyll-a hydrolysis in a high temperature environment (50-60 °C). Moreover, the immobilized enzyme retained a residual activity of more than 64% of its initial enzyme activity after 14 cycles in a repeated-batch operation. Therefore, APTES-coated MIONP-immobilized recombinant CrCLH1 can be repeatedly used to lower costs and is potentially useful for the industrial production of chlorophyll derivatives.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Chlamydomonas reinhardtii/enzimologia , Clorofila/química , Compostos Férricos/química , Proteínas de Algas/química , Proteínas de Algas/genética , Proteínas de Algas/metabolismo , Biocatálise , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/genética , Chlamydomonas reinhardtii/química , Chlamydomonas reinhardtii/genética , Fenômenos Eletromagnéticos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Nanopartículas/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
7.
J Nat Prod ; 78(7): 1556-62, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26125648

RESUMO

Antrodia cinnamomea is a scarce, epiphyte, host-specific, brown-rot fungus that produces diverse bioactive compounds with potent biological activity. Natural wild-type fruiting bodies of A. cinnamomea are rare and highly valued, but their artificial culture poses challenges. Triterpenoids are a group of secondary metabolites that contribute to the bioactivities of A. cinnamomea. 2,3-Oxidosqualene cyclase (OSC) is a key enzyme in triterpenoid biosynthesis, which converts 2,3-oxidosqualene (OS) into polycyclic triterpenoids. In this study, we isolated a 2,3-oxidosqualene cyclase gene from A. cinnamomea with degenerate primers and designated it as AcOSC. The full length AcOSC cDNA was subcloned into a yeast expression vector, and AcOSC activity was confirmed. RT-PCR results showed that AcOSC expression was highest in the wild-type fruiting body and correlated with a higher concentration of triterpenoids. Agrobacterium-mediated gene transformation was conducted to enhance the triterpenoid synthesis capacity of the cultured mycelium. Metabolite profiling was conducted by LC-MS/MS and principal component analysis (PCA). The compositions and contents of metabolites in the AcOSC transgenic lines were different from those in the wild-type mycelium and vector control. The levels of two important triterpenoids, dehydrosulphurenic acid (DSA) and dehydroeburicoic acid (DEA), were increased in A. cinnamomea oxidosqualene cyclase overexpression strains compared to controls. In summary an Agrobacterium-mediated gene transformation procedure was established that successfully increased the level of transgene expression and enhanced the triterpenoid content in cultured A. cinnamomea.


Assuntos
Antrodia/genética , Transferases Intramoleculares/isolamento & purificação , Triterpenos/metabolismo , Antrodia/química , Carpóforos/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Estrutura Molecular , Micélio , Esqualeno/análogos & derivados , Esqualeno/química , Taiwan
8.
Molecules ; 20(3): 3744-57, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25719743

RESUMO

Recombinant Brassica oleracea chlorophyllase 1 (BoCLH1) with a protein molecular weight of 38.63 kDa was successfully expressed in E. coli and could catalyze chlorophyll (Chl) hydrolysis to chlorophyllide and phytol in vitro. In this study, we used DIAION®CR11, a highly porous cross-linked polystyrene divinylbenzene-based metal chelator, for purifying and immobilizing the poly (His)-tagged enzyme. The Cu(II) showed the highest protein adsorption (9.2 ± 0.43 mg/g gel) and enzyme activity (46.3 ± 3.14 U/g gel) for the immobilization of the poly (His)-tagged recombinant BoCLH1 compared with other metal chelators. Biochemical analysis of the immobilized enzyme showed higher chlorophyllase activity for Chl a hydrolysis in a weak base environment (pH 8.0), and activity above 70% was in a high-temperature environment, compared with the free enzyme. In addition, compared with free BoCLH1, the enzyme half-life (t1/2) of the immobilized BoCLH1 increased from 25.42 to 54.35 min (approximately two-fold) at 60 °C. The immobilized enzyme retained a residual activity of approximately 60% after 17 cycles in a repeated-batch operation. Therefore, DIAION®CR11Cu(II)-immobilized recombinant BoCLH1 can be repeatedly used to lower the cost and is potentially useful for the industrial production of chlorophyllide and phytol.


Assuntos
Brassica/enzimologia , Hidrolases de Éster Carboxílico/isolamento & purificação , Hidrolases de Éster Carboxílico/metabolismo , Clorofila/metabolismo , Clorofilídeos/metabolismo , Enzimas Imobilizadas/metabolismo , Fitol/metabolismo , Proteínas Recombinantes/metabolismo , Hidrolases de Éster Carboxílico/genética , Catálise , Quelantes/química , Quelantes/metabolismo , Clorofila A , Reagentes de Ligações Cruzadas/química , Enzimas Imobilizadas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Meia-Vida , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Poliestirenos/química , Poliestirenos/metabolismo , Proteínas Recombinantes/genética , Compostos de Vinila/química , Compostos de Vinila/metabolismo
9.
Molecules ; 19(8): 11800-15, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25105918

RESUMO

Enzymes have a wide variety of applications in diverse biotechnological fields, and the immobilization of enzymes plays a key role in academic research or industrialization due to the stabilization and recyclability it confers. In this study, we immobilized the Brassica oleracea chlorophyllase 1 (BoCLH1) or Candida rugosa lipase (CRL) in magnetic iron oxide nanoparticles-loaded alginate composite beads. The catalytic activity and specific activity of the BoCLH1 and CRL entrapped in magnetic alginate composite beads were evaluated. Results show that the activity of immobilized BoCLH1 in magnetic alginate composite beads (3.36±0.469 U/g gel) was higher than that of immobilized BoCLH1 in alginate beads (2.96±0.264 U/g gel). In addition, the specific activity of BoCLH1 beads (10.90±1.521 U/mg protein) was higher than that immobilized BoCLH1 in alginate beads (8.52±0.758 U/mg protein). In contrast, the immobilized CRL in magnetic alginate composite beads exhibited a lower enzyme activity (11.81±0.618) than CRL immobilized in alginate beads (94.83±7.929), and the specific activity of immobilized CRL entrapped in magnetic alginate composite beads (1.99±0.104) was lower than immobilized lipase in alginate beads (15.01±1.255). A study of the degradation of magnetic alginate composite beads immersed in acidic solution (pH 3) shows that the magnetic alginate composite beads remain intact in acidic solution for at least 6 h, indicating the maintenance of the enzyme catalytic effect in low-pH environment. Finally, the enzyme immobilized magnetic alginate composite beads could be collected by an external magnet and reused for at least six cycles.


Assuntos
Biotecnologia , Hidrolases de Éster Carboxílico/química , Enzimas Imobilizadas/química , Lipase/química , Alginatos/química , Brassica/enzimologia , Candida/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Estabilidade Enzimática , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Lipase/metabolismo , Fenômenos Magnéticos , Temperatura
10.
Biomedicines ; 11(4)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37189810

RESUMO

The protein p53 is a well-known tumor suppressor that plays a crucial role in preventing cancer development [...].

11.
BMC Genomics ; 13: 309, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22793791

RESUMO

BACKGROUND: GDSL esterases/lipases are a newly discovered subclass of lipolytic enzymes that are very important and attractive research subjects because of their multifunctional properties, such as broad substrate specificity and regiospecificity. Compared with the current knowledge regarding these enzymes in bacteria, our understanding of the plant GDSL enzymes is very limited, although the GDSL gene family in plant species include numerous members in many fully sequenced plant genomes. Only two genes from a large rice GDSL esterase/lipase gene family were previously characterised, and the majority of the members remain unknown. In the present study, we describe the rice OsGELP (Oryza sativa GDSL esterase/lipase protein) gene family at the genomic and proteomic levels, and use this knowledge to provide insights into the multifunctionality of the rice OsGELP enzymes. RESULTS: In this study, an extensive bioinformatics analysis identified 114 genes in the rice OsGELP gene family. A complete overview of this family in rice is presented, including the chromosome locations, gene structures, phylogeny, and protein motifs. Among the OsGELPs and the plant GDSL esterase/lipase proteins of known functions, 41 motifs were found that represent the core secondary structure elements or appear specifically in different phylogenetic subclades. The specification and distribution of identified putative conserved clade-common and -specific peptide motifs, and their location on the predicted protein three dimensional structure may possibly signify their functional roles. Potentially important regions for substrate specificity are highlighted, in accordance with protein three-dimensional model and location of the phylogenetic specific conserved motifs. The differential expression of some representative genes were confirmed by quantitative real-time PCR. The phylogenetic analysis, together with protein motif architectures, and the expression profiling were analysed to predict the possible biological functions of the rice OsGELP genes. CONCLUSIONS: Our current genomic analysis, for the first time, presents fundamental information on the organization of the rice OsGELP gene family. With combination of the genomic, phylogenetic, microarray expression, protein motif distribution, and protein structure analyses, we were able to create supported basis for the functional prediction of many members in the rice GDSL esterase/lipase family. The present study provides a platform for the selection of candidate genes for further detailed functional study.


Assuntos
Esterases/genética , Genoma de Planta , Lipase/genética , Oryza/genética , Proteínas de Plantas/genética , Mapeamento Cromossômico , Biologia Computacional , Esterases/química , Esterases/classificação , Regulação da Expressão Gênica de Plantas , Genômica , Lipase/química , Lipase/classificação , Família Multigênica , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/classificação , Estrutura Terciária de Proteína
12.
Biomedicines ; 10(7)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35884795

RESUMO

The members of the p53 family comprise p53, p63, and p73, and full-length isoforms of the p53 family have a tumor suppressor function. However, p53, but not p63 or p73, has a high mutation rate in cancers causing it to lose its tumor suppressor function. The top and second-most prevalent p53 mutations are missense and nonsense mutations, respectively. In this review, we discuss possible drug therapies for nonsense mutation and a missense mutation in p53. p63 and p73 activators may be able to replace mutant p53 and act as anti-cancer drugs. Herein, these p63 and p73 activators are summarized and how to improve these activator responses, particularly focusing on p53 gain-of-function mutants, is discussed.

13.
Biomolecules ; 11(8)2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34439782

RESUMO

Chlorophyllides can be found in photosynthetic organisms. Generally, chlorophyllides have a-, b-, c-, d-, and f-type derivatives, and all chlorophyllides have a tetrapyrrole structure with a Mg ion at the center and a fifth isocyclic pentanone. Chlorophyllide a can be synthesized from protochlorophyllide a, divinyl chlorophyllide a, or chlorophyll. In addition, chlorophyllide a can be transformed into chlorophyllide b, chlorophyllide d, or chlorophyllide f. Chlorophyllide c can be synthesized from protochlorophyllide a or divinyl protochlorophyllide a. Chlorophyllides have been extensively used in food, medicine, and pharmaceutical applications. Furthermore, chlorophyllides exhibit many biological activities, such as anti-growth, antimicrobial, antiviral, antipathogenic, and antiproliferative activity. The photosensitivity of chlorophyllides that is applied in mercury electrodes and sensors were discussed. This article is the first detailed review dedicated specifically to chlorophyllides. Thus, this review aims to describe the definition of chlorophyllides, biosynthetic routes of chlorophyllides, purification of chlorophyllides, and applications of chlorophyllides.


Assuntos
Técnicas Biossensoriais/métodos , Química Farmacêutica/métodos , Clorofila/análogos & derivados , Clorofilídeos/síntese química , Aditivos Alimentares/química , Protoclorifilida/metabolismo , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/biossíntese , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Técnicas Biossensoriais/instrumentação , Clorofila/biossíntese , Clorofila/farmacologia , Clorofilídeos/biossíntese , Clorofilídeos/farmacologia , Técnicas Eletroquímicas , Aditivos Alimentares/metabolismo , Humanos , Luz , Estrutura Molecular , Fotossíntese/fisiologia , Plantas/química , Plantas/metabolismo
14.
Plants (Basel) ; 10(4)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918943

RESUMO

The fungus Antrodia cinnamomea has been used as a folk medicine for various diseases, especially cancer. When A. cinnamomea is cultured on the original host, an endangered woody plant Cinnamomum kanehirai Hayata, the fungus produces more active ingredients, but its growth is slow. Here, C. kanehirai leaf ethanol extract (KLEE) was used as a substitute for C. kanehirai wood to culture A. cinnamomea on solid medium to shorten the culture period and produce active metabolites en masse. The antioxidant activities of methanol extracts from A. cinnamomea cultured on KLEE (MEAC-KLEE) were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect, reducing power, and ferrous ion-chelating effect, and the effective concentration (EC50) values were 0.27, 0.74, and 0.37 mg mL-1, respectively. MEAC-KLEE exhibited specific anti-proliferative activity against a non-small-cell lung cancer cell line (A549) by Annexin V assay. A secondary metabolite (2,4-dimethoxy-6-methylbenzene-1,3-diol, DMMB) present in the extract (MEAC-KLEE) was purified by high-performance liquid chromatography (HPLC) and identified by nuclear magnetic resonance (NMR) spectra. DMMB exhibited moderate antioxidant activity against DPPH radicals and reducing power, with EC50 values of 12.97 and 25.59 µg mL-1, respectively, and also induced apoptosis in A549 cells. Our results provide valuable insight into the development of DMMB for nutraceutical biotechnology.

15.
PLoS One ; 16(4): e0250565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33930043

RESUMO

The purity of chlorophylls plays one of the key role for the production of chlorophyllides. We have designed a facile method for chlorophyll purification by twice solvent extraction. Twice extraction causes the loss of chlorophylls, but the purity of total chlorophylls can be enhanced 182%. Then, the purified chlorophylls can be converted to relatively pure chlorophyllides facilely. The results show that higher purity of chlorophyllides could be obtained when purified chlorophylls (ethanol-hexane extract) was used as starting materials than that of crude chlorophylls (ethanol-only extract). In biocompatibility test, the results showed that the prepared chlorophyllides can be applied as biomaterials. When the prepared chlorophyllides were applied to anticancer tests, they were active both in MCF7 and MDA-MB-231 (multidrug resistant breast cancer cells) cell lines. In addition, the results suggested that the prepared chlorophyllides could be a potential candidate of combination therapy with doxorubicin to breast cancers.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Clorofila/isolamento & purificação , Clorofilídeos/farmacologia , Resistência a Múltiplos Medicamentos/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Clorofila/química , Clorofila/farmacologia , Clorofilídeos/biossíntese , Clorofilídeos/química , Doxorrubicina/efeitos adversos , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Células MCF-7 , Linfócitos T Citotóxicos/efeitos dos fármacos
16.
Biochim Biophys Acta ; 1794(10): 1467-73, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19540368

RESUMO

Escherichia coli possesses a versatile protein with the enzyme activities of thioesterase I, protease I, and lysophospholipase L(1). The protein is dubbed as TAP according to the chronological order of gene discovery (TesA/ApeA/PldC). Our previous studies showed that TAP comprises the catalytic triad Ser(10), Asp(154), and His(157) as a charge relay system, as well as Gly(44) and Asn(73) residues devoted to oxyanion hole stabilization. Geometrically, about 10 A away from the enzyme catalytic cleft, Trp(23) showed a stronger resonance shift than the backbone amide resonance observed in the nuclear magnetic resonance (NMR) analyses. In the present work, we conducted site-directed mutagenesis to change Trp into alanine (Ala), phenylalanine (Phe), or tyrosine (Tyr) to unveil the role of the Trp(23) indole ring. Biochemical analyses of the mutant enzymes in combination with TAP's three-dimensional structures suggest that by interlinking the residues participating in this catalytic machinery, Trp(23) could effectively influence substrate binding and the following turnover number. Moreover, it may serve as a contributor to both H-bond and aromatic-aromatic interaction in maintaining the cross-link within the interweaving framework of protein.


Assuntos
Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Lisofosfolipase/química , Lisofosfolipase/metabolismo , Proteínas Periplásmicas/química , Proteínas Periplásmicas/metabolismo , Substituição de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , Primers do DNA/genética , DNA Bacteriano/genética , Estabilidade Enzimática , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Ligação de Hidrogênio , Cinética , Lisofosfolipase/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Peptídeo Hidrolases/química , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Proteínas Periplásmicas/genética , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Termodinâmica , Tioléster Hidrolases/química , Tioléster Hidrolases/genética , Tioléster Hidrolases/metabolismo , Triptofano/química
18.
Appl Biochem Biotechnol ; 191(1): 112-124, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31956956

RESUMO

Esterases are widely used in the food industry. Here, a new thermophilic bacterium, Geobacillus thermodenitrificans PS01, was isolated and the esterase-encoding gene est1 was cloned, sequenced, and recombinant expressed in Escherichia coli Tuner (DE3). The highest activity of recombinant Est1 was detected at pH 8.0, and 40 °C and the extreme stability was observed at pH 6-9 over 30 days at 4 °C. In particular, Est1 can hydrolyze short- to medium-chain (C2-C10) triglycerides and p-nitrophenyl esters (C2-C12) and was not inhibited by most metal ions. Kinetic parameters of p-nitrophenyl butyrate hydrolysis under optimal conditions were determined: Km, 22.76 µM; kcat, 10,415 s-1; and kcat/Km, 457.53 µM-1 s-1. The outstanding specification of Est1 indicates its potential for use in industrial applications.


Assuntos
Proteínas de Bactérias , Esterases , Geobacillus/enzimologia , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Esterases/biossíntese , Esterases/química , Esterases/genética , Esterases/isolamento & purificação , Geobacillus/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
19.
Food Chem ; 306: 125300, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31562927

RESUMO

Chlorophyll is a valuable bioactive compound, which is used as a natural food coloring agent and a photosensitizer for photodynamic therapy because of its antioxidant properties, antimutagenic ability, and near-infrared fluorescence. However, chlorophyll is unstable when it comes to retaining its antioxidant activity, when exposed to oxygen, high temperature, or light environments. To enhance the stability of chlorophyll, a polymer encapsulation method was proposed. Polycaprolactone (PCL) was employed to encapsulate the chlorophyll, and the particles size of the composites was controlled through droplet microfluidics. The composites (chlorophyll-encapsulated PCL particles) were characterized through UV-VIS spectrometry, SEM, optical microscopy, and light exposure. The particles were spherical, with diameters adjustable from 68 to 247 µm. Additionally, the chlorophyll-encapsulated PCL particles exhibited considerably prolonged chlorophyll stability. The solid microparticle is more convenient for storage and transportation, and have great potential for application in the food industry.


Assuntos
Clorofila/química , Poliésteres/química , Microfluídica/métodos , Tamanho da Partícula
20.
Front Pharmacol ; 11: 575704, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33328984

RESUMO

Cordyceps militaris (C. militaris) is a fungus with a long history of widespread use in folk medicine, and its biological and medicinal functions are well studied. A crucial pharmacological effect of C. militaris is immunomodulation. In this review, we catalog the immunomodulatory effects of different extracts of C. militaris, namely total extracts, polysaccharides and cordycepin. Total extracts obtained using water or 50% ethyl alcohol and polysaccharides from C. militaris were discovered to tend to promote type 1 immunity, whereas total extracts obtained using 70-80% ethyl alcohol and cordycepin from C. militaris were more likely to promote type 2 immunity. This article is the first to classify the immunomodulatory effects of different extracts of C. militaris. In addition, we discovered a relationship between different segments or extracts and differing types of immunity. This review can provide the readers a comprehensive understanding on the immunomodulatory effects of the precious folk medicine and guidance on its use for both health people and those with an immunodeficiency.

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