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1.
Neurotherapeutics ; 21(4): e00355, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38580511

RESUMEN

Mitochondria are essential organelles for cell survival that manage the cellular energy supply by producing ATP. Mitochondrial dysfunction is associated with various human diseases, including metabolic syndromes, aging, and neurodegenerative diseases. Among the diseases related to mitochondrial dysfunction, Parkinson's disease (PD) is the second most common neurodegenerative disease and is characterized by dopaminergic neuronal loss and neuroinflammation. Recently, it was reported that mitochondrial transfer between cells occurred naturally and that exogenous mitochondrial transplantation was beneficial for treating mitochondrial dysfunction. The current study aimed to investigate the therapeutic effect of mitochondrial transfer on PD in vitro and in vivo. The results showed that PN-101 mitochondria isolated from human mesenchymal stem cells exhibited a neuroprotective effect against 1-methyl-4-phenylpyridinium, 6-hydroxydopamine and rotenone in dopaminergic cells and ameliorated dopaminergic neuronal loss in the brains of C57BL/6J mice injected 30 â€‹mg/kg of methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intraperitoneally. In addition, PN-101 exhibited anti-inflammatory effects by reducing the expression of pro-inflammatory cytokines in microglial cells and suppressing microglial activation in the striatum. Furthermore, intravenous mitochondrial treatment was associated with behavioral improvements during the pole test and rotarod test in the MPTP-induced PD mice. These dual effects of neuroprotection and anti-neuroinflammation support the potential for mitochondrial transplantation as a novel therapeutic strategy for PD.

2.
Pflugers Arch ; 475(2): 267-275, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36278983

RESUMEN

Mitochondria transplantation emerges as an effective therapeutic strategy for ischemic-related diseases but the roles in the donor hearts for transplant remain unidentified. Here, we investigated whether the preservation of the donor heart with human platelet-derived mitochondria (pl-MT) could improve mitochondrial and cardiac function. Incubation with pl-MT resulted in the internalization of pl-MT and the enhancement of ATP production in primary cardiomyocytes. In addition, incubation of rat hearts with pl-MT ex vivo for 9 h clearly demonstrated pl-MT transfusion into the myocardium. Mitochondria isolated from the hearts incubated with pl-MT showed increased mitochondrial membrane potential and greater ATP synthase activity and citrate synthase activity. Importantly, the production of reactive oxygen species from cardiac mitochondria was not different with and without pl-MT incubation. Functionally, the heartbeat and the volume of coronary circulation perfusate were significantly increased in the Langendorff perfusion system and the viability of cardiomyocytes was increased from pl-MT hearts.Taken together, these results suggest that incubation with Pl-MT improves mitochondrial activity and maintains the cardiac function of rat hearts with prolonged preservation time. The study provides the proof of principle for pl-MT application as an enhancer of the donor heart.


Asunto(s)
Trasplante de Corazón , Ratas , Animales , Humanos , Donantes de Tejidos , Miocardio , Corazón , Miocitos Cardíacos , Adenosina Trifosfato
3.
Platelets ; 34(1): 2151996, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36529914

RESUMEN

Platelets are known to improve the wound-repair capacity of mesenchymal stem cells (MSCs) by transferring mitochondria intercellularly. This study aimed to investigate whether direct transfer of mitochondria (pl-MT) isolated from platelets could enhance wound healing in vitro using a cell-based model. Wound repairs were assessed by 2D gap closure experiment in wound scratch assay using human dermal fibroblasts (hDFs). Results demonstrated that pl-MT were successfully internalized into hDFs. It increased cell proliferation and promoted the closure of wound gap. Importantly, pl-MT suppressed both intracellular and mitochondrial ROS production induced by hydrogen peroxide, cisplatin, and TGF-ß in hDFs. Taken together, these results suggest that pl-MT transfer might be used as a potential therapeutic strategy for wound repair.


What is the context? During the wound healing process, abnormal regulation of ROS and inflammation delays the healing process, resulting in chronic non-healing wounds.Mitochondria are key organelles responsible for the ROS generation. Mitochondrial dysfunction has been implicated in delayed wound repair.Mitochondria transfer, which utilizes intact mitochondria isolated from healthy cells to recover from disease, has been applied in various clinical studies, but additional evidence is needed to apply it to wound healing.What is new? In this study, we chose platelets as a cell source for mitochondrial transfer. We isolated the functional mitochondria from platelets and applied them to wound healing.What is the impact? This study provides evidence that platelet-derived mitochondria (pl-MT) improve the wound healing progress by increasing the viability of dermal fibroblasts and suppressing intracellular and mitochondrial ROS production.Platelets have also been demonstrated to be a suitable cell source for mitochondrial transfer.


Asunto(s)
Plaquetas , Cicatrización de Heridas , Humanos , Plaquetas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Fibroblastos , Mitocondrias
4.
Int J Mol Sci ; 23(24)2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36555376

RESUMEN

Mitochondria are organelles that play a vital role in cellular survival by supplying ATP and metabolic substrates via oxidative phosphorylation and the Krebs cycle. Hence, mitochondrial dysfunction contributes to many human diseases, including metabolic syndromes, neurodegenerative diseases, cancer, and aging. Mitochondrial transfer between cells has been shown to occur naturally, and mitochondrial transplantation is beneficial for treating mitochondrial dysfunction. In this study, the migration of mitochondria was tracked in vitro and in vivo using mitochondria conjugated with green fluorescent protein (MTGFP). When MTGFP were used in a coculture model, they were selectively internalized into lung fibroblasts, and this selectivity depended on the mitochondrial functional states of the receiving fibroblasts. Compared with MTGFP injected intravenously into normal mice, MTGFP injected into bleomycin-induced idiopathic pulmonary fibrosis model mice localized more abundantly in the lung tissue, indicating that mitochondrial homing to injured tissue occurred. This study shows for the first time that exogenous mitochondria are preferentially trafficked to cells and tissues in which mitochondria are damaged, which has implications for the delivery of therapeutic agents to injured or diseased sites.


Asunto(s)
Fibrosis Pulmonar Idiopática , Mitocondrias , Ratones , Humanos , Animales , Mitocondrias/metabolismo , Pulmón/metabolismo , Fibrosis Pulmonar Idiopática/metabolismo , Fibroblastos/metabolismo
5.
BMB Rep ; 55(7): 361, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35892133

RESUMEN

[Erratum to: BMB Reports 2022; 55(3): 136-141, PMID: 34488927, PMCID: PMC8972135] The BMB Reports would like to correct in BMB Rep. 55(3):136-141, titled "Human umbilical cord mesenchymal stem cell-derived mitochondria (PN-101) attenuate LPS-induced inflammatory responses by inhibiting NFκB signaling pathway". This research was supported by NRF-2016R1A2B4007640 grant (to C-H Kim). Since grant number is incorrect, this information has now been corrected as follows: We would like to thank various Paean Biotechnology Inc. members who participated in the project. This work was supported by NRF-2018M3A9B5023055 grant (to C-H Kim). The authors apologize for any inconvenience or confusion that may be caused by this error. The ACKNOWLEDGEMENTS of Original PDF version have been corrected.

6.
BMB Rep ; 55(3): 136-141, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34488927

RESUMEN

Inflammation is one of the body's natural responses to injury and illness as part of the healing process. However, persistent inflammation can lead to chronic inflammatory diseases and multi-organ failure. Altered mitochondrial function has been implicated in several acute and chronic inflammatory diseases by inducing an abnormal inflammatory response. Therefore, treating inflammatory diseases by recovering mitochondrial function may be a potential therapeutic approach. Recently, mitochondrial transplantation has been proven to be beneficial in hyperinflammatory animal models. However, it is unclear how mitochondrial transplantation attenuates inflammatory responses induced by external stimuli. Here, we isolated mitochondria from umbilical cord-derived mesenchymal stem cells, referred as to PN-101. We found that PN-101 could significantly reduce LPS-induced mortality in mice. In addition, in phorbol 12-myristate 13-acetate (PMA)-treated THP-1 macrophages, PN-101 attenuated LPS-induced increase production of pro-inflammatory cytokines. Furthermore, the anti-inflammatory effect of PN-101 was mediated by blockade of phosphorylation, nuclear translocation, and trans-activity of NFκB. Taken together, our results demonstrate that PN-101 has therapeutic potential to attenuate pathological inflammatory responses. [BMB Reports 2022; 55(3): 136-141].


Asunto(s)
Lipopolisacáridos , Células Madre Mesenquimatosas , Animales , Citocinas/metabolismo , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo , Lipopolisacáridos/farmacología , Células Madre Mesenquimatosas/metabolismo , Ratones , Mitocondrias/metabolismo , FN-kappa B/metabolismo , Transducción de Señal , Cordón Umbilical/metabolismo
7.
Dermatol Ther ; 33(6): e14530, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33174271

RESUMEN

Treatment for hair loss is largely limited, and any beneficial effects are often transient. Based on the critical role of the FGF5 isoform, FGF5s, in the hair growth cycle, it may be a good therapeutic candidate for the prevention of hair loss, as well as the promotion of hair growth. To investigate its potential use for hair growth, a mutant form of the FGF5s protein (FGF5sC93S) was generated, expressed, and purified. The FGF5sC93S mutant was able to antagonize FGF5-induced mitogenic activity, which normally triggers the conversion of hair follicles from the anagen phase to the catagen phase. In addition, the FGF5sC93S mutant efficiently suppressed gene expression induced by FGF5 both human outer root sheath (hORS) and human dermal papilla (hDP) cells. Administration of FGF5sC93S proteins onto the scalps of human subjects significantly increased the total number of hairs at 24 weeks. Together, our data demonstrate that a mutant form of the FGF5s protein could be used as a potential hair promoting agent.


Asunto(s)
Cisteína , Factores de Crecimiento de Fibroblastos , Alopecia/tratamiento farmacológico , Alopecia/genética , Factores de Crecimiento de Fibroblastos/genética , Cabello , Folículo Piloso , Humanos
8.
Lab Chip ; 19(4): 580-588, 2019 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-30623953

RESUMEN

Intracellular delivery of functional molecules such as proteins, transcription factors and DNA is effective and promising in cell biology. However, existing transfection methods are often unsuitable to deliver big molecules into cells or require carriers such as viruses and peptides specific to the target molecules. In addition, the nature of bulk processing does not generally provide accurate dose control of individual cells. The concept of single-cell-based material injection based on electrokinetic pumping through nanocapillaries could overcome these problems, yet the fabrication and operation of nanoscale 3-dimensional structures have remained unsolved. In this research, a hybrid (PDMS/glass) microfluidic chip with a true 3-dimensional nanoinjection structure (called "nanoinjection system") is presented. The nanoinjection structure was fabricated by femtosecond-laser (fs-laser) ablation in a single solid glass, which showed very successful delivery of red fluorescent protein (RFP) and expression of plasmid DNA in several different types of cells. This system is promising in that the amount of molecules to be delivered is controllable and the processed cells are systematically separated into a harvesting chamber, which can radically improve the purity of the processed cells. In addition, it was confirmed that the cells were healthy even after the molecule injection for a few seconds, indicating that the injection time can be significantly elongated, further improving the delivery efficiency of biomolecules without affecting the cell viability. We envision that the nanoinjection system having the major features of being carrier-free and dose-controllable, having an unlimited injection period, and ease of harvesting will greatly contribute to the next-generation research studies in the fields of cell biology and cell therapeutics.


Asunto(s)
ADN/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Proteínas Luminiscentes/metabolismo , Células Madre Mesenquimatosas/química , Células Madre Mesenquimatosas/metabolismo , Nanotecnología , Células Cultivadas , ADN/administración & dosificación , Proteínas Fluorescentes Verdes/administración & dosificación , Humanos , Proteínas Luminiscentes/administración & dosificación , Células Madre Mesenquimatosas/citología , Nanotecnología/instrumentación , Plásmidos/administración & dosificación , Plásmidos/metabolismo , Proteína Fluorescente Roja
9.
BMB Rep ; 52(5): 324-329, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30293549

RESUMEN

Recent progress in cellular reprogramming technology and lineage-specific cell differentiation has provided great opportunities for translational research. Because virus-based gene delivery is not a practical reprogramming protocol, protein-based reprogramming has been receiving attention as a safe way to generate reprogrammed cells. However, the poor efficiency of the cellular uptake of reprogramming proteins is still a major obstacle. Here, we reported key factors which improve the cellular uptake of these proteins. Purified red fluorescent proteins fused with 9xLysine (dsRED-9K) as a cell penetrating peptide were efficiently delivered into the diverse primary cells. Protein delivery was improved by the addition of amodiaquine. Furthermore, purified dsRED-9K was able to penetrate all cell lineages derived from mouse embryonic stem cells efficiently. Our data may provide important insights into the design of protein-based reprogramming or differentiation protocols [BMB Reports 2019; 52(5): 324-329].


Asunto(s)
Péptidos de Penetración Celular/metabolismo , Técnicas de Reprogramación Celular/métodos , Polilisina/metabolismo , Amodiaquina/farmacología , Animales , Técnicas de Cultivo de Célula , Diferenciación Celular/genética , Péptidos de Penetración Celular/farmacología , Reprogramación Celular/genética , Células Madre Embrionarias/citología , Fibroblastos/metabolismo , Técnicas de Transferencia de Gen , Células HEK293 , Humanos , Células Madre Pluripotentes Inducidas/citología , Ratones , Péptidos/uso terapéutico , Polilisina/uso terapéutico , Factores de Transcripción/metabolismo
10.
Ann Dermatol ; 29(6): 828, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29200788

RESUMEN

[This corrects the article on p. 187 in vol. 29, PMID: 28392646.].

11.
Ann Dermatol ; 29(2): 187-193, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28392646

RESUMEN

BACKGROUND: Micro-needle patches have been recently used to increase skin permeability, which improves drug delivery, and for cosmetic purposes. However, these patches may often have limited efficacy due to insufficient skin penetration and reduced compliance caused by discomfort. OBJECTIVE: We evaluated the efficacy and the safety of soluble micro-spicule containing epidermal growth factor (MS-EGF) for the treatment of periocular wrinkles. METHODS: Twenty healthy volunteers aged 33 to 54 years were enrolled in a randomized, controlled, split-face study. For 4 weeks, a periocular wrinkle was treated daily with either a soluble MS-EGF cream or a cream containing EGF alone. All subjects underwent 8 weeks of follow-up. Efficacy was assessed using an ultrasonic measurement of dermal depth and density, digital skin image analysis, 5-point photonumeric scale for periocular wrinkles and subjective satisfaction. RESULTS: MS-EGF group showed statistically significant increase of dermal depth and density compared to EGF alone group after 4 and 8 weeks. In addition, there was a marked improvement shown in clinical and 3-dimensional skin image in MS-EGF group. The treatments were well-tolerated; no significant side-effect was noted. CONCLUSION: The MS-EGF formulation may represent an effective and biocompatible advance in the treatment of periocular wrinkles.

12.
Biol Pharm Bull ; 36(3): 425-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23449328

RESUMEN

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is an important regulator of the maturation and function of cells in the granulocyte and macrophage lineages, and also plays a significant role in wound healing. In a previous study, we expressed human GM-CSF in rice cells (rice cell-derived human GM-CSF; rhGM-CSF). The purpose of the present study was to evaluate its effect on wound healing in oral mucositis. Oral mucositis was induced in Syrian hamster cheek pouches by 5-fluorouracil treatment and mechanical scratching. Ulcerated areas were treated from days 3 to 14 with an application of 200 µL saline, or of the same volume of a solution containing 0.04, 0.2, or 1 µg/mL rhGM-CSF. Treatment of hamsters with rhGM-CSF reduced the ulcerated areas of the oral mucosa, compared with the control. Early in the healing process, the mucositis tissue layer of the rhGM-CSF-treated group showed significantly decreased myeloperoxidase activity and increased numbers of proliferating cell nuclear antigen (PCNA)-positive cells. Treatment with rhGM-CSF also affected expression of inflammatory cytokines in the ulcerative mucosal tissue. These results demonstrate the efficacy of plant-produced rhGM-CSF in wound healing and have significant implications for the development of rhGM-CSF as a therapeutic agent for ulcerative oral mucositis.


Asunto(s)
Antimetabolitos Antineoplásicos/toxicidad , Fluorouracilo/toxicidad , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Estomatitis/tratamiento farmacológico , Animales , Cricetinae , Interleucina-1beta/genética , Masculino , Mesocricetus , Mucosa Bucal/efectos de los fármacos , Mucosa Bucal/enzimología , Oryza/genética , Peroxidasa/metabolismo , Antígeno Nuclear de Célula en Proliferación/análisis , Proteínas Recombinantes/uso terapéutico , Estomatitis/inducido químicamente , Estomatitis/patología , Factor de Crecimiento Transformador beta/genética , Cicatrización de Heridas/efectos de los fármacos
13.
Appl Environ Microbiol ; 79(7): 2253-62, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23354713

RESUMEN

It was previously proposed that regio-specific hydroxylation of an immunosuppressive cyclosporine (CsA) at the 4th N-methyl leucine is mediated by cytochrome P450 hydroxylase (CYP) in the rare actinomycete Sebekia benihana. This modification is thought to be the reason for the hair growth-promoting side effect without the immunosuppressive activity of CsA. Through S. benihana genome sequencing and in silico analysis, we identified the complete cytochrome P450 complement (CYPome) of S. benihana, including 21 CYPs and their electron transfer partners, consisting of 7 ferredoxins (FDs) and 4 ferredoxin reductases (FDRs). Using Escherichia coli conjugation-based S. benihana CYPome-targeted disruption, all of the identified CYP, FD, and FDR genes in S. benihana were individually inactivated. Among the 32 S. benihana exconjugant mutants tested, only a single S. benihana CYP mutant, ΔCYP-sb21, failed to exhibit CsA hydroxylation activity. The hydroxylation was restored by CYP-sb21 gene complementation. Since all S. benihana FD and FDR disruption mutants maintained CsA hydroxylation activity, it can be concluded that CYP-sb21, a new member of the bacterial CYP107 family, is the only essential component of the in vivo regio-specific CsA hydroxylation process in S. benihana. Moreover, expression of an extra copy of the CYP-sb21 gene increased CsA hydroxylation in wild-type S. benihana and an NADPH-enriched Streptomyces coelicolor mutant, by 2-fold and 1.5-fold, respectively. These results show for the first time that regio-specific hydroxylation of CsA is carried out by a specific P450 hydroxylase present in S. benihana, and they set the stage for the biotechnological application of regio-specific CsA hydroxylation through heterologous CYP-sb21 expression.


Asunto(s)
Actinomycetales/enzimología , Ciclosporina/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Oxigenasas de Función Mixta/metabolismo , Actinomycetales/genética , Biología Computacional , Sistema Enzimático del Citocromo P-450/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Escherichia coli/genética , Técnicas de Inactivación de Genes , Prueba de Complementación Genética , Genoma Bacteriano , Oxigenasas de Función Mixta/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Streptomyces coelicolor/genética
14.
Appl Microbiol Biotechnol ; 95(1): 157-68, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22382166

RESUMEN

Polyene antibiotics such as nystatin are a large family of very valuable antifungal polyketide compounds typically produced by soil actinomycetes. Previously, using a polyene cytochrome P450 hydroxylase-specific genome screening strategy, Pseudonocardia autotrophica KCTC9441 was determined to contain an approximately 125.7-kb region of contiguous DNA with a total of 23 open reading frames, which are involved in the biosynthesis and regulation of a structurally unique polyene natural product named NPP. Here, we report the complete structure of NPP, which contains an aglycone identical to nystatin and harbors a unique di-sugar moiety, mycosaminyl-(α1-4)-N-acetyl-glucosamine. A mutant generated by inactivation of a sole glycosyltransferase gene (nppDI) within the npp gene cluster can be complemented in trans either by nppDI-encoded protein or by its nystatin counterpart, NysDI, suggesting that the two sugars might be attached by two different glycosyltransferases. Compared with nystatin (which bears a single sugar moiety), the di-sugar containing NPP exhibits approximately 300-fold higher water solubility and 10-fold reduced hemolytic activity, while retaining about 50% antifungal activity against Candida albicans. These characteristics reveal NPP as a promising candidate for further development into a pharmacokinetically improved, less-cytotoxic polyene antifungal antibiotic.


Asunto(s)
Actinomycetales/genética , Actinomycetales/metabolismo , Antifúngicos/metabolismo , Ingeniería Genética/métodos , Hemólisis , Nistatina , Polienos , Actinomycetales/enzimología , Antifúngicos/química , Biotecnología/métodos , Candida albicans/efectos de los fármacos , Proteínas Fúngicas/genética , Pruebas de Sensibilidad Microbiana , Familia de Multigenes , Mutación , Nistatina/biosíntesis , Nistatina/química , Polienos/química , Polienos/metabolismo , Solubilidad , Relación Estructura-Actividad
15.
J Microbiol Biotechnol ; 21(1): 14-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21301187

RESUMEN

A cyclic undecapeptide-family natural product, cyclosporin A (CyA), which is one of the most valuable immunosuppressive drugs, is produced nonribosomally by a multifunctional cyclosporin synthetase enzyme complex in a filamentous fungal strain named Tolypocladium niveum. Previously, structural modifications of cyclosporins such as a regionspecific hydroxylation at the 4th N-methyl leucine in a rare actinomycetes called Sebekia benihana were reported to lead to dramatic changes in their bioactive spectra. However, the reason behind this change could not be determined since a system to genetically manipulate S. benihana has not yet been developed. To address this limitation, in this study, we utilized the most commonly practiced gene manipulation techniques including conjugation-based foreign gene transfer-and-expression as well as targeted gene disruption to genetically manipulate S. benihana. Using these optimized genetic manipulation systems, a putative cytochrome P450 hydroxylase (CYP) gene named CYP506, which is involved in CyA hydroxylation in S. benihana, was specifically disrupted and genetically complemented. The S. benihana deltaCYP506 exhibited a significantly reduced CyA hydroxylation yield as well as considerable yield restoration by functional complementation of the S. benihana CYP506 gene, suggesting that the genetically manipulated S. benihana CYP mutant strains may serve as a more efficient bioconversion host for various valuable metabolites including CyA.


Asunto(s)
Actinobacteria/enzimología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Ciclosporina/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Silenciador del Gen , Actinobacteria/genética , Actinobacteria/metabolismo , Prueba de Complementación Genética , Hidroxilación , Datos de Secuencia Molecular
16.
J Ind Microbiol Biotechnol ; 38(4): 573-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21259033

RESUMEN

Using the genomics-guided polyene screening method, a rare actinomycetes called Pseudonocardia autotrophica was previously identified to contain functionally clustered nystatin-like biosynthetic genes and to produce a presumably novel polyene compound named nystatin-like Pseudonocardia polyene (NPP) (Kim et al., J Ind Microbiol Biotechnol 36:1425-1434, 2009). Since very low NPP productivity was observed in most P. autotrophica culture conditions, its biosynthetic pathway was proposed to be tightly regulated. Herein we report in silico analysis of six putative NPP pathway-specific regulatory genes present in its biosynthetic gene cluster, followed by functional overexpression of these regulatory genes in P. autotrophica. Three pathway-specific regulatory genes (nppRI, RIII, and RV) were predicted to belong to a typical LAL-type transcriptional family. Each regulatory gene was cloned under the strong constitutive ermE* promoter in a Streptomyces integrative pSET152 plasmid, followed by direct intergeneric conjugation from a plasmid-containing E. coli donor cell to P. autotrophica. While all the P. autotrophica exconjugants exhibited improved NPP productivity, the one containing nppRIII showed the highest NPP productivity improvement. In addition, culture-time-dependent analysis revealed that the nppRIII-stimulated NPP biosynthesis was more significant in the late exponential growth stage than in the stationary stage. Moreover, the P. autotrophica nppRIII-disruption mutant failed to produce NPP, with significantly reduced transcription levels of most npp biosynthetic genes. The results described suggest that identification and overexpression of key pathway-specific regulatory gene, followed by optimum harvest timing, should be critical factors to maximize the productivity of an intrinsically low-level metabolite such as NPP produced by rare actinomycetes species.


Asunto(s)
Actinomycetales/genética , Macrólidos/metabolismo , Actinomycetales/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Vías Biosintéticas/genética , Genes Reguladores , Datos de Secuencia Molecular , Nistatina/metabolismo , Polienos/metabolismo , Alineación de Secuencia
17.
Appl Environ Microbiol ; 76(18): 6295-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20656866

RESUMEN

Herewith we report the expression and screening of microbial enzymes without involving cloning procedures. Computationally predicted putative omega-transaminase (omega-TA) genes were PCR amplified from the bacterial colonies and expressed in a cell-free protein synthesis system for subsequent analysis of their enzymatic activity and substrate specificity. Through the cell-free expression analysis of the putative omega-TA genes, a number of enzyme-substrate pairs were identified in a matter of hours. We expect that the proposed strategy will provide a universal platform for bridging the information gap between nucleotide sequence and protein function to accelerate the discovery of novel enzymes.


Asunto(s)
Expresión Génica , Ensayos Analíticos de Alto Rendimiento/métodos , Transaminasas/genética , Sistema Libre de Células , Cromatografía Líquida de Alta Presión , Colorimetría , Cartilla de ADN/genética , Técnicas de Amplificación de Ácido Nucleico , Reacción en Cadena de la Polimerasa , Especificidad por Sustrato
18.
J Microbiol Biotechnol ; 19(9): 869-72, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19809241

RESUMEN

The cyclic undecapeptide cyclosporin A (CyA), one of the most valuable immunosuppressive drugs, is produced nonribosomally by a multifunctional cyclosporin synthetase enzyme complex by the filamentous fungus Tolypocladium niveum. To increase CyA productivity by wild-type T. niveum (ATCC 34921), random mutagenesis was first performed using an antifungal agar-plug colony assay (APCA) selection approach. This generated a mutant strain producing more than 9-fold greater CyA than the wild-type strain. Additionally, a foreign bacterial gene, Vitreoscilla hemoglobin gene (VHb), was transformed via protoplast regeneration and its transcription was confirmed by RT-PCR in the UV-irradiated mutant cell. This led to an additional 33.5% increase of CyA production. Although most protoplastregenerated T. niveum transformants tend to lose CyA productivity, the optimized combination of random mutagenesis and protoplast transformation described here should be an efficient strategy to generate a commercially valuable, yet metabolite low-producing, fungal species, such as CyA producing T. niveum.


Asunto(s)
Ciclosporina/metabolismo , Hypocreales/metabolismo , Protoplastos/metabolismo , Proteínas Bacterianas/genética , Genes Bacterianos , Hypocreales/genética , Hypocreales/fisiología , Mutagénesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética , Hemoglobinas Truncadas/genética , Vitreoscilla/genética
19.
Toxicol Res ; 24(4): 315-320, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32038810

RESUMEN

Recombinant human granulocyte-macrophage colony stimulating factor (hGM-CSF) is a glycoprotein and hematopoietic growth factors that regulates the proliferation of myeloid precursor cells and activates mature granulocytes and macrophages. In a previous study, we reported that hGM-CSF could be produced in transgenic rice cell suspension culture, termed rhGM-CSF. In the present study, we examined the repeated dose toxicity of rhGM-CSF in SD rats. The repeated dose toxicity study was performed at each dose of 50 and 200 µg/kg subcutaneous administration of rhGM-CSF everyday for 28-days period. The results did not show any changes in food and water intake. There were also no significant changes in both body and organ weights between the control and the tested groups. The hematological and blood biochemical parameters were statistically not different in all groups. These results suggest that rhGM-CSF may show no repeated dose toxicity in SD rats under the conditions.

20.
J Ind Microbiol Biotechnol ; 33(2): 84-7, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16096834

RESUMEN

The polyene antibiotics, a category that includes nystatin, pimaricin, amphotericin, and candicidin, comprise a family of very promising antifungal polyketide compounds and are typically produced by soil actinomycetes. The biosynthetic gene clusters for these polyenes have been previously investigated, revealing the presence of highly similar cytochrome P450 hydroxylase (CYP) genes. Using polyene CYP-specific PCR screening with several actinomycete genomic DNAs, Pseudonocardia autotrophica was determined to contain a unique polyene-specific CYP gene. Genomic DNA library screening using the polyene-specific CYP gene probe identified a positive cosmid clone, which contained a DNA fragment of approximately 34.5 kb. The complete sequencing of this DNA fragment revealed a total of seven complete and two incomplete open reading frames, which were found to be highly similar, but still unique, when compared to previously known polyene biosynthetic genes. These results suggest that the polyene-specific screening approach may constitute an efficient method for the isolation of potentially valuable cryptic polyene biosynthetic gene clusters from various rare actinomycetes.


Asunto(s)
Actinomycetales/enzimología , Antibacterianos/biosíntesis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Familia de Multigenes , Polienos/metabolismo , Actinomycetales/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Clonación Molecular , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/aislamiento & purificación , Sistema Enzimático del Citocromo P-450/metabolismo , Técnicas Genéticas , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
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