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3.
Artigo em Inglês | MEDLINE | ID: mdl-30298129

RESUMO

Cell- and gene-based therapies form one of the pillars of regenerative medicine. They have the potential to transform quality of life and improve the health status of patients with genetic and cellular defects, including genetic diseases, neurodegenerative diseases and tissue malignancies, amongst others. Despite numerous challenges, in the last decade, tremendous unified efforts by research and clinical scientists in academic, translational and industry settings have resulted in tangible outcomes in the form of many marketing authorizations and approved commercial firsts, such as Glybera®, Kymriah®, YESCARTA®, Holoclar®, and Luxturna™. This report presents a succinct analysis of developments in the regenerative medicine landscape, including immuno-oncology, with a focus on the European Union and examples of clinical and commercial successes and failures. The factors that led to these exciting developments in immune-oncology are also considered. Concurrently, several key issues, spanning from the identification of unmet clinical need, associated challenges, economic evaluation to policy improvements are emphasized. Furthermore, industry insights encompassing the five-dimensional research and development framework for the focused development of medicine, pricing and reimbursement issues, technology adoption and permeation of innovative advanced therapy medicinal products in the clinical set up are reflected upon, following elaborate discussions that transpired in different thematic tracks of Tissue Engineering & Regenerative Medicine International Society European Chapter 2017 Industry Symposium.

4.
Regen Med ; 12(8): 997-1013, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29243940

RESUMO

Medicinal signaling cell (MSC)-based products represent emerging treatments in various therapeutic areas including cardiometabolic, inflammation, autoimmunity, orthopedics, wound healing and oncology. Exploring innovation beyond minimally manipulated plastic-adherent ex vivo expanded allogeneic MSCs enables product delineation. Product delineation is on the critical path to maximize clinical benefits and market access. An innovation framework is presented here along various innovation dimensions comprising composition-of-matter by means of positive cell surface markers, formulation varying for example the cell dose or the preservation mode and medium, manufacturing to adapt the secretome of MSCs to the condition of interest, the mode of delivery and corresponding delivery devices, as well as molecular engineering and biomarkers. The rationale of the innovation space thus described applies generally to all cell-based therapies.

5.
Tissue Eng Part B Rev ; 23(2): 199-210, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27762892

RESUMO

"Evaluating the Past and Present of Regenerative Medicine (RM)" was the first part of an Industry Symposium dedicated to the subject during the 2015 TERMIS World Congress in Boston. This working session presented a critical review of the current RM landscape in Europe and North America with possible projections for the future. Interestingly, the RM development cycle seems to obey the Gartner hype cycle, now at the enlightenment phase, after past exaggerated expectations and discouragements, as suggested by increasing numbers of clinical trials and recent market approvals of RM solutions in both Europe (Glybera and Holoclar® from Chiesi Pharma and Strimvelis® from GSK) and Japan (Remestemcel-L from Mesoblast®). The successful commercial translation of RM research is governed by five major drivers: (i) fully validated manufacturing capability for autologous or allogeneic products, (ii) reimbursement for targeted clinical indications with high and demonstrable medico-economic benefits versus standard of care, (iii) implication of regulatory bodies in the design and development plan of any RM solution, which should be well characterized, robust, with proven consistent efficacy and an acceptable and controlled positive benefit/risk ratio, (iv) collaborations facilitated by multicompetence hubs/consortia of excellence, (v) well-thought-out clinical development plans for reducing the risk of failure. Benefiting from past and present experience, the RM burgeoning industry is expected to accelerate the market release of cost-effective RM products with real curative potential for specific clinical indications with high unmet needs. This should be achieved by wisely leveraging all possible synergies of the different stakeholders, for example, patients, clinicians, reimbursement and health technology assessment (HTA) agencies, regulatory authorities, public/private investors, academia, and companies.


Assuntos
Internacionalidade , Medicina Regenerativa/tendências , Animais , Bioengenharia , Ensaios Clínicos como Assunto , Comportamento Cooperativo , Humanos
6.
Tissue Eng Part B Rev ; 21(6): 560-71, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26179129

RESUMO

The TERMIS-Europe (EU) Industry committee intended to address the two main critical issues in the clinical/commercial translation of Advanced Therapeutic Medicine Products (ATMP): (1) entrepreneurial exploitation of breakthrough ideas and innovations, and (2) regulatory market approval. Since January 2012, more than 12,000 publications related to regenerative medicine and tissue engineering have been accepted for publications, reflecting the intense academic research activity in this field. The TERMIS-EU 2014 Industry Symposium provided a reflection on the management of innovation and technological breakthroughs in biotechnology first proposed to contextualize the key development milestones and constraints of allocation of financial resources, in the development life-cycle of radical innovation projects. This was illustrated with the biofuels story, sharing similarities with regenerative medicine. The transition was then ensured by an overview of the key identified challenges facing the commercialization of cell therapy products as ATMP examples. Real cases and testimonies were then provided by a palette of medical technologies and regenerative medicine companies from their commercial development of cell and gene therapy products. Although the commercial development of ATMP is still at the proof-of-concept stage due to technology risks, changing policies, changing markets, and management changes, the sector is highly dynamic with a number of explored therapeutic approaches, developed by using a large diversity of business models, both proposed by the experience, pitfalls, and successes of regenerative medicine pioneers, and adapted to the constraint resource allocation and environment in radical innovation projects.


Assuntos
Medicina Regenerativa , Engenharia Tecidual , Humanos , Medicina Regenerativa/economia , Medicina Regenerativa/métodos , Medicina Regenerativa/tendências , Engenharia Tecidual/economia , Engenharia Tecidual/métodos , Engenharia Tecidual/tendências
7.
Regen Med ; 10(3): 331-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25933241

RESUMO

Hematopoietic stem cell transplantation is a life-saving treatment for inherited anemias, immunodeficiencies or hematologic malignancies. When using partially HLA-matched allografts, a major complication is graft-versus-host disease (GvHD). The ideal attributes of a transformational new GvHD treatment include improved survival, decreased corticosteroids, decreased antifungals, improved quality of life through decreased infections, reduced number of hospital stay days, reduced risks of developing chronic GvHD impact on lower GI tract and liver, prophylactic benefits and decreased GvHD relapses, but, in the case of cancer, without negatively impacting beneficial graft-versus-tumor effects. The current practice of hematopoietic stem cell transplantation, its incidence and its unmet medical needs are reviewed here and discussed.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Hematopoese/imunologia , Transplante de Células-Tronco Hematopoéticas , Recuperação de Função Fisiológica/imunologia , Anemia/imunologia , Anemia/terapia , Animais , Doença Enxerto-Hospedeiro/imunologia , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/terapia , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/terapia
8.
Regen Med ; 10(3): 345-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25933242

RESUMO

Hematopoietic stem cell transplantation (HSCT) is a life-saving treatment for inherited anemias, immunodeficiencies or hematologic malignancies. A major complication of allo-HSCT associated with high transplant-related mortality rates is graft-versus-host disease (GvHD). Current and future clinical benefits in HSCT enabled by advances in hematopoietic stem cells, mesenchymal stem cells, Tregs and natural killer cells technologies are reviewed here and discussed. Among these evolutions, based on the need for mesenchymal stem cells to be recruited by an inflammatory environment, the development and use of novel GvHD biomarkers could be explored further to deliver the right pharmaceutical to the right patient at the right time. The successful commercialization of cytotherapeutics to efficiently manage GvHD will create a virtuous 'halo' effect for regenerative medicine.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Hematopoese/imunologia , Transplante de Células-Tronco Hematopoéticas , Recuperação de Função Fisiológica/imunologia , Medicina Regenerativa , Anemia/imunologia , Anemia/terapia , Animais , Biomarcadores , Terapia Baseada em Transplante de Células e Tecidos/métodos , Terapia Baseada em Transplante de Células e Tecidos/tendências , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/prevenção & controle , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/terapia , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/terapia , Medicina Regenerativa/métodos , Medicina Regenerativa/tendências
9.
Appl Microbiol Biotechnol ; 99(11): 4679-89, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25820644

RESUMO

We previously reported on the impacts of the overexpression of individual genes of the glycolytic pathway encoding glucokinase (GLK), glyceraldehyde phosphate dehydrogenase (GAPDH), phosphofructokinase (PFK), triosephosphate isomerase (TPI), and bisphosphate aldolase (FBA) on D-lactate productivity in Corynebacterium glutamicum under oxygen-deprived conditions. Searching for synergies, in the current study, we simultaneously overexpressed the five glycolytic genes in a stepwise fashion to evaluate the effect of the cumulative overexpression of glycolytic genes on D-lactate production. Interestingly, the final D-lactate concentration markedly differed depending on whether or not the PFK encoding gene was overexpressed when combined with overexpressing other glycolytic genes. The simultaneous overexpression of the GLK, GAPDH, TPI, and FBA encoding genes led to the highest initial D-lactate concentration at 10 h. However, this particular recombinant strain dramatically slowed producing D-lactate when a concentration of 1300 mM was reached, typically after 32 h. In contrast, the strain overexpressing the PFK encoding gene together with the GLK, GAPDH, TPI, and FBA encoding genes showed 12.7 % lower initial D-lactate concentration at 10 h than that observed with the strain overexpressing the genes coding for GLK, GAPDH, TPI, and FBA. However, this recombinant strain continued to produce D-lactate after 32 h, reaching 2169 mM after a mineral salts medium bioprocess incubation period of 80 h. These results suggest that overexpression of the PFK encoding gene is essential for achieving high production of D-lactate. Our findings provide interesting options to explore for using C. glutamicum for cost-efficient production of D-lactate at the industrial scale.


Assuntos
Corynebacterium glutamicum/enzimologia , Corynebacterium glutamicum/metabolismo , Ácido Láctico/metabolismo , Oxigênio/metabolismo , Fosfofrutoquinases/metabolismo , Corynebacterium glutamicum/genética , Meios de Cultura/química , Expressão Gênica , Fosfofrutoquinases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fatores de Tempo
10.
Regen Med ; 9(4): 479-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25159065

RESUMO

The slow adoption of cytotherapeutics remains a vexing hurdle given clinical progress achieved to date with a variety of stem cell lineages. Big and midsize pharmaceutical companies as an asset class still delay large-scale investments in this arena until technological and market risks will have been further reduced. Nonetheless, a handful of stem cell strategic alliance and licensing transactions have already been implemented, indicating that progress is actively monitored, although most of these involve midsize firms. The greatest difficulty is, perhaps, that the regenerative medicine industry is currently only approaching the point of inflexion of the technology development S-curve, as many more clinical trials read out. A path to accelerating technology adoption is to focus on innovation outliers among healthcare actors. These can be identified by analyzing systemic factors (e.g., national science policies and industry fragmentation) and intrinsic factors (corporate culture, e.g., nimble decision-making structures; corporate finance, e.g., opportunity costs and ownership structure; and operations, e.g., portfolio management strategies, threats on existing businesses and patent expirations). Another path is to accelerate the full clinical translation and commercialization of an allogeneic cytotherapeutic product in any indication to demonstrate the disease-modifying potential of the new products for treatment and prophylaxis, ideally for a large unmet medical need such as dry age-related macular degeneration, or for an orphan disease such as biologics-refractory acute graft-versus-host disease. In times of decreased industry average research productivities, regenerative medicine products provide important prospects for creating new franchises with a market potential that could very well mirror that achieved with the technology of monoclonal antibodies.


Assuntos
Técnicas de Cultura de Células/economia , Terapia Baseada em Transplante de Células e Tecidos/economia , Indústria Farmacêutica/economia , Transplante de Células-Tronco/economia , Células-Tronco , Aloenxertos , Técnicas de Cultura de Células/métodos , Indústria Farmacêutica/métodos , Humanos
11.
Tissue Eng Part B Rev ; 20(4): 246-56, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24754565

RESUMO

The Tissue Engineering & Regenerative Medicine International Society-Europe (TERMIS-EU) Industry Committee as well as its TERMIS-Americas (AM) counterpart intend to address the specific challenges and needs facing the industry in translating academic research into commercial products. Over the last 3 years, the TERMIS-EU Industry Committee has worked with commercial bodies to deliver programs that encourage academics to liaise with industry in proactive collaborations. The TERMIS-EU 2013 Industry Symposium aimed to build on this commercial agenda by focusing on two topics: Operations Management (How to move a process into the good manufacturing practice [GMP] environment) and Clinical Translation (Moving a GMP process into robust trials). These topics were introduced by providing the synergistic business perspective of partnering between the multiple regenerative medicine stakeholders, throughout the life cycle of product development. Seven industry leaders were invited to share their experience, expertise, and strategies. Due to the complex nature of regenerative medicine products, partnering for their successful commercial development seems inevitable to overcome all obstacles by sharing experiences and expertise of all stakeholders. When ideally implemented, the "innovation quotient" of a virtual team resulting from the combination of internal and external project teams can be maximized through maximizing the three main dimensions: core competences, technology portfolio, and alliance management.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Medicina Regenerativa , Pesquisa Translacional Biomédica , Humanos
12.
Annu Rev Microbiol ; 66: 521-50, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22803796

RESUMO

Corynebacterium glutamicum exhibits numerous ideal intrinsic attributes as a factory of primary and secondary metabolites. The versatile capabilities of this organism have long been implemented at the industrial scale to produce an array of amino acids at high yields and conversion rates, thereby enabling the development of an entire industry. The postgenomic era provides a new technological platform not only to further optimize the intrinsic attributes of C. glutamicum whole cells as biocatalysts, but also to dramatically expand the product portfolio that can be manufactured by this organism, from amino acids to commodity chemicals. This review addresses the methods and strain optimization strategies enabled by genomic information and associated techniques. Their implementation has provided important additional incremental improvements to the economics of industry-scale manufacturing in which C. glutamicum and its episomal elements are used as a performing host-vector system.


Assuntos
Corynebacterium glutamicum/enzimologia , Corynebacterium glutamicum/genética , Enzimas/genética , Enzimas/metabolismo , Biotecnologia/métodos , Corynebacterium glutamicum/metabolismo , Microbiologia Industrial/métodos , Engenharia Metabólica/métodos , Redes e Vias Metabólicas/genética
13.
J Ind Microbiol Biotechnol ; 39(2): 255-68, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21861158

RESUMO

Desulfitobacterium hafniense Y51 is a dechlorinating bacterium that encodes an unusually large set of O-demethylase paralogs and specialized respiratory systems including specialized electron donors and acceptors. To use this organism in bioremediation of tetrachloroethene (PCE) or trichloroethene (TCE) pollution, expression patterns of its 5,060 genes were determined under different conditions using 60-mer probes in DNA microarrays. PCE, TCE, fumarate, nitrate, and dimethyl sulfoxide (DMSO) respiration all sustain the growth of strain Y51. Global transcriptome analyses were thus performed using various electron donor and acceptor couples (respectively, pyruvate and either fumarate, TCE, nitrate, or DMSO, and vanillate/fumarate). When TCE is used as terminal electron acceptor, resulting in its detoxification, a series of electron carriers comprising a cytochrome bd-type quinol oxidase (DSY4055-4056), a ferredoxin (DSY1451), and four Fe-S proteins (DSY1626, DSY1629, DSY0733, DSY3309) are upregulated, suggesting that the products of these genes are involved in PCE oxidoreduction. Interestingly, the PCE dehalogenase cluster (pceABCT) is constitutively expressed in the media tested, with pceT being upregulated and pceC downregulated in pyruvate/TCE-containing medium. In addition, another dehalogenation enzyme (DSY1155 coding for a putative chlorophenol reductive dehalogenase), is induced 225-fold in that medium, despite not being involved in PCE respiration. Remarkably since the reducing equivalents formed during pyruvate conversion to acetyl-CoA are channeled to electron acceptors including halogenated compounds, pyruvate induces expression of a pyruvate:ferredoxin oxidoreductase. This study paves the way to understanding the physiology of D. hafniense, optimizing this microbe as a bioremediation agent, and designing bioarray sensors to monitor the presence of dechlorinating organisms in the environment.


Assuntos
Desulfitobacterium/genética , Tetracloroetileno/metabolismo , Animais , Biodegradação Ambiental , Desulfitobacterium/crescimento & desenvolvimento , Desulfitobacterium/metabolismo , Perfilação da Expressão Gênica , Halogenação , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/metabolismo , Oxidantes/metabolismo , Oxirredução , Oxirredutases/genética , Oxirredutases/metabolismo , Oxirredutases O-Desmetilantes/genética , Oxirredutases O-Desmetilantes/metabolismo , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Transcriptoma , Tricloroetileno/metabolismo , Poluentes Químicos da Água/metabolismo
14.
Appl Microbiol Biotechnol ; 91(5): 1375-87, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21655984

RESUMO

Corynebacterium glutamicum encodes a mannitol catabolic operon, which comprises three genes: the DeoR-type repressor coding gene mtlR (sucR), an MFS transporter gene (mtlT), and a mannitol 2-dehydrogenase gene (mtlD). The mtlR gene is located upstream of the mtlTD genes in the opposite orientation. In spite of this, wild-type C. glutamicum lacks the ability to utilize mannitol. This wild-type phenotype results from the genetic regulation of the genes coding for mannitol transport and catalytic proteins mediated by the autoregulated MtlR protein since mtlR mutants grow on mannitol as the sole carbon source. MtlR binds to sites near the mtlR (two sites) and mtlTD promoters (one site downstream of the promoter), with the consensus sequence 5'-TCTAACA-3' being required for its binding. The newly discovered operon comprises the three basic functional elements required for mannitol utilization: regulation, transport, and metabolism to fructose, further processed to the common intermediate of glycolysis fructose-6-phosphate. When relieved from MtlR repression, C. glutamicum, which lacks a functional fructokinase, excretes the fructose derived from mannitol and imports it by the fructose-specific PTS. In order to use mannitol from seaweed biomass hydrolysates as a carbon source for the production of useful commodity chemicals and materials, an overexpression system using the tac promoter was developed. For congruence with the operon, we propose to rename sucR as the mtlR gene.


Assuntos
Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Manitol/metabolismo , Óperon , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Regulação Bacteriana da Expressão Gênica , Dados de Sequência Molecular , Regiões Promotoras Genéticas
15.
Appl Environ Microbiol ; 75(11): 3419-29, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19346355

RESUMO

Corynebacterium glutamicum ATCC 31831 grew on l-arabinose as the sole carbon source at a specific growth rate that was twice that on d-glucose. The gene cluster responsible for l-arabinose utilization comprised a six-cistron transcriptional unit with a total length of 7.8 kb. Three l-arabinose-catabolizing genes, araA (encoding l-arabinose isomerase), araB (l-ribulokinase), and araD (l-ribulose-5-phosphate 4-epimerase), comprised the araBDA operon, upstream of which three other genes, araR (LacI-type transcriptional regulator), araE (l-arabinose transporter), and galM (putative aldose 1-epimerase), were present in the opposite direction. Inactivation of the araA, araB, or araD gene eliminated growth on l-arabinose, and each of the gene products was functionally homologous to its Escherichia coli counterpart. Moreover, compared to the wild-type strain, an araE disruptant exhibited a >80% decrease in the growth rate at a lower concentration of l-arabinose (3.6 g liter(-1)) but not at a higher concentration of l-arabinose (40 g liter(-1)). The expression of the araBDA operon and the araE gene was l-arabinose inducible and negatively regulated by the transcriptional regulator AraR. Disruption of araR eliminated the repression in the absence of l-arabinose. Expression of the regulon was not repressed by d-glucose, and simultaneous utilization of l-arabinose and d-glucose was observed in aerobically growing wild-type and araR deletion mutant cells. The regulatory mechanism of the l-arabinose regulon is, therefore, distinct from the carbon catabolite repression mechanism in other bacteria.


Assuntos
Arabinose/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Genes Bacterianos , Família Multigênica , Aerobiose , Carboidratos Epimerases/genética , Corynebacterium glutamicum/crescimento & desenvolvimento , DNA Bacteriano/química , DNA Bacteriano/genética , Escherichia coli/genética , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Genes , Glucose/metabolismo , Proteínas de Membrana Transportadoras/genética , Redes e Vias Metabólicas/genética , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência
16.
J Mol Microbiol Biotechnol ; 15(1): 16-30, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18349547

RESUMO

The current paradigm to produce biotechnological ethanol is to use the yeast Saccharomyces cerevisiae to ferment sugars derived from starch or sugar crops such as maize, sugar cane or sugar beet. Despite its current success, the global impact of this manufacturing model is restricted on the one hand by limits on the availability of these primary raw materials, and on the other hand by the maturity of baker's yeast fermentation technologies. Revisiting the technical, economic, and value chain aspects of the biotechnological ethanol industry points to the need for radical innovation to complement the current manufacturing model. Implementation of lignocellulosic materials is clearly a key enabler to the billion-ton biofuel vision. However, realization of the full market potential of biofuels will be facilitated by the availability of an array of innovative technological options, as the flexibility generated by these alternative processes will not only enable the exploitation of heretofore untapped local market opportunities, but also it will confer to large biorefinery structures numerous opportunities for increased process integration as well as optimum reactivity to logistic and manufacturing challenges. In turn, all these factors will interplay in synergy to contribute in shifting the economic balance in favor of the global implementation of biotechnological ethanol.


Assuntos
Biotecnologia/tendências , Fontes Geradoras de Energia , Etanol/metabolismo , Glucose/metabolismo , Microbiologia Industrial/tendências , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Tecnologia
17.
J Bacteriol ; 190(9): 3264-73, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18296524

RESUMO

The narKGHJI operon that comprises putative nitrate/nitrite transporter (narK) and nitrate reductase (narGHJI) genes is required for the anaerobic growth of Corynebacterium glutamicum with nitrate as a terminal electron acceptor. In this study, we identified a gene, arnR, which encodes a transcriptional regulator that represses the expression of the narKGHJI operon in C. glutamicum cells under aerobic conditions. Disruption of arnR induced nitrate reductase activities of C. glutamicum cells and increased narKGHJI mRNA levels under aerobic growth conditions. DNA microarray analyses revealed that besides the narKGHJI operon, the hmp gene, which encodes flavohemoglobin, is negatively regulated by ArnR under aerobic conditions. Promoter-reporter assays indicated that arnR gene expression was positively autoregulated by its gene product, ArnR, under both aerobic and anaerobic conditions. Electrophoretic mobility shift assay experiments showed that purified hexahistidyl-tagged ArnR protein specifically binds to promoter regions of the narKGHJI operon and the hmp and arnR genes. A consensus sequence, TA(A/T)TTAA(A/T)TA, found in the promoter regions of these genes was demonstrated to be involved in the binding of ArnR. Effects on LacZ activity by deletion of the ArnR binding sites within the promoter regions fused to the reporter gene were consistent with the view that the expression of the narKGHJI operon is repressed by the ArnR protein under aerobic conditions, whereas the expression of the arnR gene is autoinduced by ArnR.


Assuntos
Proteínas de Transporte de Ânions/genética , Proteínas de Bactérias/metabolismo , Corynebacterium glutamicum/genética , Regulação Bacteriana da Expressão Gênica , Nitrato Redutase/genética , Óperon/genética , Proteínas Repressoras/metabolismo , Aerobiose/genética , Proteínas de Bactérias/genética , Sequência de Bases , Sítios de Ligação , Sequência Consenso , Ensaio de Desvio de Mobilidade Eletroforética , Retroalimentação Fisiológica/genética , Genes Reporter , Hemeproteínas/genética , Proteínas Ferro-Enxofre/genética , Dados de Sequência Molecular , Transportadores de Nitrato , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , beta-Galactosidase/genética
18.
Appl Microbiol Biotechnol ; 77(5): 1053-62, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17965859

RESUMO

Corynebacterium glutamicum was metabolically engineered to broaden its substrate utilization range to include the pentose sugar L-arabinose, a product of the degradation of lignocellulosic biomass. The resultant CRA1 recombinant strain expressed the Escherichia coli genes araA, araB, and araD encoding L-arabinose isomerase, L-ribulokinase, and L-ribulose-5-phosphate 4-epimerase, respectively, under the control of a constitutive promoter. Unlike the wild-type strain, CRA1 was able to grow on mineral salts medium containing L-arabinose as the sole carbon and energy source. The three cloned genes were expressed to the same levels whether cells were cultured in the presence of D-glucose or L-arabinose. Under oxygen deprivation and with L-arabinose as the sole carbon and energy source, strain CRA1 carbon flow was redirected to produce up to 40, 37, and 11%, respectively, of the theoretical yields of succinic, lactic, and acetic acids. Using a sugar mixture containing 5% D-glucose and 1% L-arabinose under oxygen deprivation, CRA1 cells metabolized L-arabinose at a constant rate, resulting in combined organic acids yield based on the amount of sugar mixture consumed after D-glucose depletion (83%) that was comparable to that before D-glucose depletion (89%). Strain CRA1 is, therefore, able to utilize L-arabinose as a substrate for organic acid production even in the presence of D-glucose.


Assuntos
Arabinose/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Redes e Vias Metabólicas , Ácido Acético/metabolismo , Anaerobiose , Carbono/metabolismo , Ácidos Carboxílicos/metabolismo , Corynebacterium glutamicum/crescimento & desenvolvimento , Meios de Cultura/química , Metabolismo Energético , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/genética , Expressão Gênica , Glucose/metabolismo , Ácido Láctico/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Ácido Succínico/metabolismo
19.
Microbiology (Reading) ; 153(Pt 8): 2491-2504, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17660414

RESUMO

A transcriptional profiling of the metabolism of Corynebacterium glutamicum under oxygen deprivation conditions is reported. It was observed that the glucose consumption rate per cell when C. glutamicum cells were incubated under oxygen deprivation conditions was higher than that achieved by cells incubated under aerobic growth conditions. Furthermore, DNA microarray and quantitative RT-PCR analyses revealed that the genes of several key enzymes of the glycolytic and organic acid production pathways, including gapA, pgk, tpi, ppc, ldhA and mdh, were significantly upregulated under oxygen deprivation conditions. The corresponding enzymic activities consistently correlated with the regulation patterns of the genetic expression observed at the transcriptional level. Studies of lacZ fusions with the gapA, ldhA and mdh genes indicated not only that these genes are strongly induced at the onset of the stationary phase under aerobic growth conditions, but also that high expression levels are maintained under oxygen deprivation conditions. These results indicate that the genetic expression of several key metabolic enzymes in C. glutamicum cells incubated under oxygen deprivation conditions is chiefly regulated at the transcriptional level. The physiological consequence of the observed increased transcription under oxygen deprivation conditions is an increased rate of carbon source consumption, which is accompanied by a concomitant increase in organic acid production.


Assuntos
Ácidos Carboxílicos/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Perfilação da Expressão Gênica , Anaerobiose , Fusão Gênica Artificial , Proteínas de Bactérias/genética , Sequência de Bases , Enzimas/genética , Regulação Bacteriana da Expressão Gênica , Genes Reporter , Glucose/metabolismo , Redes e Vias Metabólicas/genética , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , RNA Bacteriano/biossíntese , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta-Galactosidase/análise , beta-Galactosidase/genética
20.
Microbiology (Reading) ; 153(Pt 4): 1042-1058, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17379713

RESUMO

The complete genome sequence of Corynebacterium glutamicum strain R was determined to allow its comparative analysis with other corynebacteria. The biology of corynebacteria was explored by refining the definition of the subset of genes that constitutes the corynebacterial core as well as those characteristic of saprophytic and pathogenic ecological niches. In addition, the relative scarcity of corynebacterial sigma factors and the plasticity of their two-component system machinery reflect their relatively exacting nutritional requirements and reduced membrane-associated and secreted proteins. The conservation of key genes and pathways between corynebacteria, mycobacteria and Nocardia validates the use of C. glutamicum to study fundamental processes that are conserved in slow-growing mycobacteria, including pathogenesis-associated mechanisms. The discovery of 39 novel genes in C. glutamicum R that have not been previously reported in other corynebacteria supports the rationale for sequencing additional corynebacterial genomes to better define the corynebacterial pan-genome and identify previously undetected metabolic pathways in these organisms.


Assuntos
Corynebacterium glutamicum/genética , Genoma Bacteriano , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Metabolismo dos Carboidratos , Corynebacterium glutamicum/metabolismo , Genômica , Dados de Sequência Molecular , Fator sigma/genética , Especificidade da Espécie
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