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1.
Psychiatr Prax ; 49(7): 359-366, 2022 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-34921366

RESUMO

Domestic violence evidently endangers health. Since physicians are seen as primary contact persons by victims of violence it is necessary to understand their perception of their role. 1346 of all physicians and dentists registered in 2015 with the Saxony Board of Physicians filled in a questionnaire on contact with victims, knowledge on support structures and willingness to take part on specific medical education. Frequency of contact was estimated to be low, while readiness to approach patients in case of suspicion was high. There was uncertainty about where to refer, as well as a limited level of awareness of existing support structures. Most indicated a high request in further education. In conclusion, motivation and readiness contrast with uncertainty and lack of awareness. Education focusing on key players and major network interfaces should endorse physicians in their significant role within the care and prevention system of violence.


Assuntos
Violência Doméstica , Violência por Parceiro Íntimo , Médicos , Violência Doméstica/prevenção & controle , Alemanha , Setor de Assistência à Saúde , Humanos , Violência por Parceiro Íntimo/prevenção & controle , Inquéritos e Questionários
2.
J Am Chem Soc ; 144(1): 153-162, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34958548

RESUMO

We describe for the first time the full reaction coordinate regarding the photoisomerization of red-absorbing norbornadienes (NBDs) to quadricyclanes (QCs). Our studies go beyond steady-state investigations by using an arsenal of time-resolved techniques. Importantly, the red absorption of NBDs is made possible by a different charge-transfer character; adjusting its strength enables control over the photoreversibility of the rearrangement. In the case of strong charge-transfer character (a weakly electron-withdrawing ester and a strongly electron-donating dimethylaniline), photoirradiation with visible light into the delocalized charge-transfer absorption of NBD affords QC reversibly. In stark contrast, UV photoirradiation into the NBD localized excited state leads to a photoinduced degradation and cannot be back-isomerized to NBD under any circumstances. If the charge-transfer character is weak (a weakly electron-withdrawing ester and a weakly electron-donating phenyl), reversibility is seen independently of the photoirradiation light.

3.
Chemistry ; 27(58): 14501-14507, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34328641

RESUMO

With respect to molecular switches, initializing the quadricyclane (QC) to norbornadiene (NBD) back-reaction by light is highly desirable. Our previous publication provided a unique solution for this purpose by utilizing covalently bound C60 . In this work, the fundamental processes within these hybrids has been investigated. Variation of the linker unit connecting the NBD/QC moiety with the fullerene core is used as a tool to tune the properties of the resulting hybrids. Utilizing the Prato reaction, two unprecedented NBD/QC - fullerene hybrids having a long-rigid and a short-rigid linker were synthesized. Molecular dynamics simulations revealed that this results in an average QC-C60 distance of up to 14.2 Å. By comparing the NBD-QC switching of these derivatives with the already established one having a flexible linker, valuable mechanistic insights were gained. Most importantly, spatial convergence of the QC moiety and the fullerene core is inevitable for an efficient back-reaction.

4.
Chemistry ; 27(15): 4993-5002, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33449419

RESUMO

Cobalt catalysts are immobilized on the surface of iron oxide nanoparticles for the preparation of highly active quasi-homogeneous catalysts toward an efficient release of photochemically stored energy in norbornadiene-based photoswitches. The facile separation of the iron oxide nanoparticles through exploitation of the intrinsic magnetic properties of this material enables efficient cyclization of energy storage and release. Through the transition from cobalt (II) salphen to cobalt porphyrins, a 22.6-fold increase in the catalytic efficiency of the QC-NBD back-conversion is achieved, with an initial TOF of up to 3.64 s-1 and excellent TON of over 3305. In addition, a series of novel "push-pull" functionalized norbornadiene derivatives is prepared, featuring excellent absorption properties with maxima up to 366 nm, quantum yields around 70 %, high energy storage capacities of up to 98.0 kJ mol-1 , and outstanding thermal stability with t1/2 (25 °C) over 100 days. Finally, the energy storage potential of these molecular solar thermal (MOST) systems is harnessed in a heat release experiment. This demonstrates the potential of norbornadiene-based photoswitches in combination with efficient magnetic catalysts for the generation of environmentally benign process heat.

5.
Chemistry ; 26(23): 5220-5230, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31773822

RESUMO

The synthesis and properties of various norbornadiene/quadricyclane (NBD/QC) fullerene hybrids are reported. By cyclopropanation of C60 with malonates carrying the NBD scaffold a small library of NBD-fullerene monoadducts and NBD-fullerene hexakisadducts was established. The substitution pattern of the NBD scaffold, as well as the electron affinity of the fullerene core within these hybrid systems, has a pronounced impact on the properties of the corresponding energy rich QC derivatives. Based on this, the first direct photoisomerization of NBD-fullerene hybrids to their QC derivatives was achieved. Furthermore, it was possible to use the redox-active fullerene core of a QC-fullerene monoadduct to enable the back reaction to form the corresponding NBD-fullerene monoadduct. Combining these two processes enables switching between NBD and QC simply by changing the irradiation wavelength between 310 and 400 nm. Therefore, turning this usually photo/thermal switch into a pure photoswitch. This not only simplifies the investigation of the underlying processes of the NBD-QC interconversion within the system, but also renders such hybrids interesting for applications as molecular switches.

6.
Sci Rep ; 9(1): 16805, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727969

RESUMO

Secondary production in freshwater zooplankton is frequently limited by the food quality of phytoplankton. One important parameter of phytoplankton food quality are essential polyunsaturated fatty acids (PUFAs). Since the fatty acid composition of phytoplankton is variable and depends on the algae's nutrient supply status, inorganic nutrient supply may affect the algal PUFA composition. Therefore, an indirect transfer of the effects of nutrient availability on zooplankton by changes in algal PUFA composition is conceivable. While the phosphorus (P) supply in lakes is largely decreasing, nitrogen (N) inputs continue to increase. This paper presents data from a mesocosm field experiment in which we exposed phytoplankton communities to increasing N enrichment. As a consequence, the PUFA composition of the phytoplankton community changed. With increasing nitrogen fertilisation, we observed lower quantities of essential PUFAs, together with a decrease in the abundances of the dominant herbivorous zooplankton Daphnia sp. Their biomass was significantly correlated with phytoplankton PUFA content (C18:3 ω3, C20:5 ω3, C18:2 ω6). Our data therefore indicate that changes in nitrogen supply, together with the resultant changes in phytoplankton food quality, can negatively affect the secondary production of herbivorous zooplankton by reducing the availability of essential polyunsaturated fatty acids.


Assuntos
Daphnia/crescimento & desenvolvimento , Ácidos Graxos Insaturados/análise , Nitrogênio/metabolismo , Fitoplâncton/fisiologia , Ração Animal , Animais , Biomassa , Daphnia/efeitos dos fármacos , Ácidos Graxos Insaturados/farmacologia , Cadeia Alimentar , Herbivoria , Fitoplâncton/química , Fitoplâncton/efeitos dos fármacos , Zooplâncton/efeitos dos fármacos , Zooplâncton/crescimento & desenvolvimento
7.
Eur J Psychotraumatol ; 10(1): 1654064, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31528269

RESUMO

Background: It is well known from cross-sectional studies that individual coping strategies significantly influence the pathogenesis of posttraumatic stress disorder (PTSD). Equally, undisputed is the role of biological processes, e.g. of the so-called 'stress hormone' cortisol for the trajectory of PTSD. Ecological momentary assessment (EMA), the repeated collection of self-reported momentary states via smartphones, is ideal for shedding light upon symptom fluctuations and coping strategies. EMA may also constitute a promising approach to provide closer associations to biomarkers than retrospective self-report. The mobile application 'CoachPTBS', created to facilitate transition into health-care systems, bridges waiting periods for trauma-specific psychotherapy. CoachPTBS offers tools akin to EMA that could elucidate coping with stress symptoms. Moreover, the app's self-management tools may improve coping strategies. However, these processes have never been examined in a combined, longitudinal fashion. Objective: The aim of the current study is to assess symptom fluctuations, coping strategies and long-term endocrine correlates of PTSD by a longitudinal, multimodal approach, combining traditional, online and EMA self-report with hair cortisol data and CoachPTBS as a possible novel mHealth tool. Method: 120 participants waiting for PTSD psychotherapy will be randomly grouped. After in-situ assessment and hair sample collection, 40 will receive CoachPTBS, using it daily throughout 4 weeks. A parallel group of 40 will participate in EMA, completing daily questionnaires on symptoms and coping. In between, online surveys will be conducted. After 6 weeks, a final interview and another hair sample collection will follow. Comparisons between these groups and waitlist-control, also consisting of 40 PTSD participants, and 40 non-traumatized participants assessed via EMA regarding aversive emotions and coping are planned. Discussion: Novel insights into the interplay of biological and coping strategies in PTSD are expected due to the innovative multimodal study design. Results will further explore benefits of eHealth tools on coping with PTSD.


Antecedentes: Es bien sabido por los estudios transversales que las estrategias de afrontamiento individuales influyen significativamente en la patogénesis del estrés postraumático (TEPT). Igualmente es indiscutible el rol de los procesos biológicos, por ej. De la llamada 'hormona del estrés', el cortisol para la trayectoria del TEPT. La evaluación ecológica del momento (EMA, por sus siglas en ingles), la que consiste en la colección repetida de estados momentáneos auto-reportados a través de teléfonos inteligentes, es ideal para arrojar luz sobre las fluctuaciones de los síntomas y estrategias de afrontamiento. La EMA puede constituir tambien un enfoque prometedor para proporcionar asociaciones más cercanas a los biomarcadores que el auto-reporte retrospectivo. La aplicación móvil 'CoachPTBS', creada para facilitar la transición en los sistemas de atención médica, une los periodos de espera para la psicoterapia específica para el trauma. CoachPTBS ofrece herramientas similares a EMA que podrían dilucidar el manejo de los síntomas de estrés. Además, las herramientas de autogestión de la aplicación pueden mejorar las estrategias de afrontamiento. Sin embargo, estos procesos nunca han sido examinados de manera longitudinal combinada.Objetivo: El objetivo de este estudio es evaluar las fluctuaciones de los síntomas, las estrategias de afrontamiento y los correlatos endocrinos a largo plazo del TEPT mediante un enfoque longitudinal y multimodal que combina el auto-reporte tradicional, en línea y EMA con información de cortisol capilar y CoachPTBS como una posible herramienta novedosa de salud móvil.Métodos: Se agruparán 120 participantes que esperan psicoterapia para TEPT. Después de una evaluación in situ y toma de muestra de cabello, 40 recibirán CoachPTBS, usándola diariamente durante cuatro semanas. Un grupo paralelo de 40 participará en EMA, completando cuestionarios diariamente acerca de los síntomas y afrontamiento. En el proceso, se realizaran encuestas en línea. Después de seis semanas, se realizará una entrevista final y otra recolección de muestras de cabello. Se planea una comparación entre estos grupos y la lista de espera, tambien consistente en 40 participantes con TEPT, y 40 participantes no traumatizados evaluados a través de EMA en relación a emociones adversas y afrontamiento.Discusión: Se esperan novedosas ideas en la interacción entre lo biológico y las estrategias de afrontamiento en TEPT debido al diseño innovador del estudio multimodal. Los resultados exploraran con mayor profundidad los beneficios de las herramientas de Salud 'electrónica' para hacer frente al TEPT.

8.
Eur J Psychotraumatol ; 10(1): 1611090, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143412

RESUMO

Background: Prevalence of post-traumatic stress disorder (PTSD) is a problem all over the world. There are high barriers for entry into formal psychotherapy, which results in a lack of mental health care for a significant part of the population. Mobile mental Health (mMHealth) applications (apps) seem to be a promising new development for countering this lack of care, building on the success of mHealth (Mobile Health) apps in general. Unfortunately, the overall quality of such apps stands in high contrast to their number. The aim of this manuscript is to propose a standard for creating PTSD-related mMHealth apps incorporating a process for evaluation and assessment of their usability and impact. Methods: This is done by first defining each step of the process and its relation to the other steps. The steps themselves, divided into those concerned with development, evaluation and implementation, are bound to the established medical and technical norms pertaining to them. Existing protocols from recent literature have been integrated into these steps. Results: As a result, a comprehensive model covering the process of creating, assessing and implementing an mMHealth app from start to finish was developed. The model may be adapted to other disorders or specialized for certain symptoms of PTSD. Conclusion: Adopting such a model could result in a 'blueprint' for creating mMHealth apps in a standardized way, thereby facilitating the testing and comparing of such apps.


Antecedentes: La prevalencia del Trastorno de Estrés Postraumatico (TEPT) es un problema en todo el mundo. Existen altas barreras para ingresar a psicoterapia formal, lo cual resulta en falta de atención de salud mental para una parte significativa de la población. Las aplicaciones (apps) móviles de salud mental (mMHealth) parecen un desarrollo nuevo y prometedor para contrarrestar esta carencia de cuidado, basado en el éxito general de las aplicaciones mHealth. Desafortunadamente, la calidad general de estas aplicaciones contrasta con su número. El objetivo de este manuscrito es proponer un estándar para crear aplicaciones mMHealth relacionadas con TEPT que incorporen un proceso para la evaluación y valoración de su utilidad e impacto.Método: Se hizo definiendo primero cada paso del proceso y su relación con los otros pasos. Los pasos en sí, divididos en aquellos concernientes con el desarrollo, evaluación e implementación, están sujetos a las normas médicas y técnicas establecidas pertinentes. Los protocolos existentes en la literatura reciente se han integrado en estos pasos.Resultados: Como resultado se desarrolló un modelo integral que cubre el proceso de creación, evaluación e implementación de una aplicación mMHealth desde el comienzo hasta el final. El modelo podría ser adaptado a otros trastornos o especializado para ciertos síntomas de TEPT.Conclusiones: La adopción de este modelo podría resultar en un 'prototipo' para crear aplicaciones mMHealth de una manera estandarizada, facilitando así la prueba y comparación de dichas aplicaciones.

9.
Methodist Debakey Cardiovasc J ; 15(1): 32-38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049147

RESUMO

Low-density lipoprotein cholesterol (LDL-C) is a well-established risk factor for atherosclerotic cardiovascular disease (ASCVD). Statins remain the first-line therapy for patients with elevated LDL-C and increased risk. However, many at-risk patients do not achieve adequate LDL-C lowering with statin monotherapy or do not tolerate statins because of side effects. Recent cardiovascular outcome trials involving ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have demonstrated efficacy of nonstatin therapies in further reducing LDL-C levels and ASCVD risk. This review highlights the available nonstatin therapeutic options and explores important novel therapeutic approaches currently under development.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Inibidores de Serina Proteinase/uso terapêutico , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , LDL-Colesterol/sangue , Ácidos Dicarboxílicos/uso terapêutico , Quimioterapia Combinada , Dislipidemias/sangue , Dislipidemias/epidemiologia , Dislipidemias/genética , Ezetimiba/uso terapêutico , Ácidos Graxos/uso terapêutico , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de PCSK9 , RNA Interferente Pequeno/uso terapêutico , Terapêutica com RNAi , Fatores de Risco , Inibidores de Serina Proteinase/efeitos adversos , Resultado do Tratamento
10.
Chembiochem ; 20(11): 1458-1466, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-30702209

RESUMO

To date, commercial laccase preparations are used in the food, textile, and paper and pulp industries (mild pH). Laccases are attractive in the synthesis of dye molecules or oxidative lignin treatment, which take place at high pH (≥8.0). So far, one fungal laccase has been reported to be active at alkaline pH. Herein, engineering of the fungal laccase from Melanocarpus albomyces (MaL) for increased activity toward the substrate 2,6-dimethoxyphenol at pH (≥9.0) is reported. Through a knowledge-gaining directed evolution (KnowVolution) campaign, the key positions Leu365 and Leu513 were identified to increase alkaline tolerance. Both positions are located in close proximity of the T1Cu site. Molecular docking and simulations studies reveal that both substitutions act in a synergic way to stabilize and improve laccase activity at higher pH. Kinetic characterization of the final variant MaL-M1 (L365E/L513M) revealed at pH 9.8 a threefold improved kcat (kcat =(6.0±0.2) s-1 ) compared with that of wild-type M. albomyces laccase (kcat =(2.11±0.07) s-1 ).


Assuntos
Proteínas Fúngicas/química , Lacase/química , Sordariales/metabolismo , Clonagem Molecular , Evolução Molecular Direcionada/métodos , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Cinética , Simulação de Acoplamento Molecular/métodos , Oxirredução , Pirogalol/análogos & derivados , Pirogalol/química , Saccharomyces cerevisiae/genética
11.
Mhealth ; 4: 15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29963560

RESUMO

Posttraumatic stress disorder (PTSD) is a global public health problem. Unfortunately, many individuals with PTSD do not receive professional care due to a lack of available providers, stigma about mental illness, and other concerns. Technology-based interventions, including mobile phone applications (apps) may be a viable means of surmounting such barriers and reaching and helping those in need. Given this potential, in 2011 the U.S Veterans Affairs National Center for PTSD released PTSD Coach, a mobile app intended to provide psycho-education and self-management tools for trauma survivors with PTSD symptoms. Emerging research on PTSD Coach demonstrates high user satisfaction, feasibility, and improvement in PTSD symptoms and other psychosocial outcomes. A model of openly sharing the app's source code and content has resulted in versions being created by individuals in six other countries: Australia, Canada, The Netherlands, Germany, Sweden, and Denmark. These versions are described, highlighting their significant adaptations, enhancements, and expansions to the original PTSD Coach app as well as emerging research on them. It is clear that the sharing of app source code and content has benefited this emerging PTSD Coach community, as well as the populations they are targeting. Despite this success, challenges remain especially reaching trauma survivors in areas where few or no other mental health resources exist.

12.
AMB Express ; 7(1): 164, 2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28831735

RESUMO

The coding sequence of a peroxidase from the secretome of Pleurotus sapidus was cloned from a cDNA library. Bioinformatic analyses revealed an open reading frame of 1551 bp corresponding to a primary translation product of 516 amino acids. The DyP-type peroxidase was heterologously produced in Trichoderma reesei with an activity of 55,000 U L-1. The enzyme was purified from the culture supernatant, biochemically characterized and the kinetic parameters were determined. The enzyme has an N-terminal signal peptide composed of 62 amino acids. Analysis by Blue Native PAGE and activity staining with ABTS, as well as gel filtration chromatography showed the native dimeric state of the enzyme (115 kDa). Analysis of the substrate range revealed that the recombinant enzyme catalyzes, in addition to the conversion of some classic peroxidase substrates such as 2,2'-azino-bis(3-ethylthiazoline-6-sulfonate) and substituted phenols like 2,6-dimethoxyphenol, also the decolorization of the anthraquinonic dye Reactive Blue 5. The enzyme also catalyzes bleaching of natural colorants such as ß-carotene and annatto. Surprisingly, ß-carotene was transformed in the presence and absence of H2O2 by rPsaDyP, however enzyme activity was increased by the addition of H2O2. This indicates that the rPsaDyP has an oxidase function in addition to a peroxidase activity. As a consequence of the high affinity to the characteristic substrate Reactive Blue 5 the rPsaDyP belongs functionally to the dyp-type peroxidase family.

13.
Microb Cell Fact ; 15: 57, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-27026185

RESUMO

BACKGROUND: Bacillus subtilis is an important cell factory for the biotechnological industry due to its ability to secrete commercially relevant proteins in large amounts directly into the growth medium. However, hyper-secretion of proteins, such as α-amylases, leads to induction of the secretion stress-responsive CssR-CssS regulatory system, resulting in up-regulation of the HtrA and HtrB proteases. These proteases degrade misfolded proteins secreted via the Sec pathway, resulting in a loss of product. The aim of this study was to investigate the secretion stress response in B. subtilis 168 cells overproducing the industrially relevant α-amylase AmyM from Geobacillus stearothermophilus, which was expressed from the strong promoter P(amyQ)-M. RESULTS: Here we show that activity of the htrB promoter as induced by overproduction of AmyM was "noisy", which is indicative for heterogeneous activation of the secretion stress pathway. Plasmids were constructed to allow real-time analysis of P(amyQ)-M promoter activity and AmyM production by, respectively, transcriptional and out-of-frame translationally coupled fusions with gfpmut3. Our results show the emergence of distinct sub-populations of high- and low-level AmyM-producing cells, reflecting heterogeneity in the activity of P(amyQ)-M. This most likely explains the heterogeneous secretion stress response. Importantly, more homogenous cell populations with regard to P(amyQ)-M activity were observed for the B. subtilis mutant strain 168degUhy32, and the wild-type strain 168 under optimized growth conditions. CONCLUSION: Expression heterogeneity of secretory proteins in B. subtilis can be suppressed by degU mutation and optimized growth conditions. Further, the out-of-frame translational fusion of a gene for a secreted target protein and gfp represents a versatile tool for real-time monitoring of protein production and opens novel avenues for Bacillus production strain improvement.


Assuntos
Amilases/biossíntese , Bacillus subtilis/crescimento & desenvolvimento , Técnicas Bacteriológicas/métodos , Amilases/genética , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Regulação Bacteriana da Expressão Gênica , Geobacillus stearothermophilus/enzimologia , Geobacillus stearothermophilus/genética , Engenharia Metabólica/métodos , Organismos Geneticamente Modificados , Via Secretória/genética
14.
Biotechnol Biofuels ; 8: 155, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26405457

RESUMO

BACKGROUND: Filamentous fungi are frequently used as production platforms in industrial biotechnology. Most of the strains involved were known as reproducing exclusively asexually thereby preventing the application of conventional strain breeding techniques. In the last decade, evidence was obtained that a number of these imperfect fungi possess a sexual life cycle, too. Trichoderma reesei, an industrial producer of enzymes for food, feed and biorefinery purposes, is heterothallic and takes a special position among industrially utilized species as all industrial strains are derived from the single MAT1-2 isolate QM6a. Consequently, strain improvement by crossing is not feasible within this strain line as this necessitates a MAT1-1 mating partner. Simply switching the mating type in one of the mating partners to MAT1-1, however, is not sufficient to produce a genotype capable of sexual reproduction with QM6a MAT1-2. RESULTS: We have used a systems biology approach to identify genes restoring sexual reproduction in the QM6a strain line. To this end, T. reesei QM6a was crossed with the MAT1-1 wild-type strain CBS999.97. The descendants were backcrossed 8-times in two lineages with QM6a to obtain mating competent MAT1-1 strains with a minimal set of CBS999.97 specific genes. Comparative genome analysis identified a total of 73 genes of which two-encoding an unknown C2H2/ankyrin protein and a homolog of the WD-protein HAM5-were identified to be essential for fruiting body formation. The introduction of a functional ham5 allele in a mating type switched T. reesei QM6a allowed sexual crossing with the parental strain QM6a. CONCLUSION: The finding that Trichoderma reesei is generally capable of undergoing sexual reproduction even under laboratory conditions raised hope for the applicability of classical breeding techniques with this fungus as known for plants and certain yeasts. The discovery that the wild-type isolate QM6a was female sterile, however, precluded any progress along that line. With the discovery of the genetic cause of female sterility and the creation of an engineered fertile strain we now provide the basis to establish sexual crossing in this fungus and herald a new era of strain improvement in T. reesei.

15.
Eukaryot Cell ; 10(11): 1527-35, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21890820

RESUMO

The conidium plays a critical role in the life cycle of many filamentous fungi, being the primary means for survival under unfavorable conditions. To investigate the transcriptional changes taking place during the transition from growing hyphae to conidia in Trichoderma reesei, microarray experiments were performed. A total of 900 distinct genes were classified as differentially expressed, relative to their expression at time zero of conidiation, at least at one of the time points analyzed. The main functional categories (FunCat) overrepresented among the upregulated genes were those involving solute transport, metabolism, transcriptional regulation, secondary metabolite synthesis, lipases, proteases, and, particularly, cellulases and hemicellulases. Categories overrepresented among the downregulated genes were especially those associated with ribosomal and mitochondrial functions. The upregulation of cellulase and hemicellulase genes was dependent on the function of the positive transcriptional regulator XYR1, but XYR1 exerted no influence on conidiation itself. At least 20% of the significantly regulated genes were nonrandomly distributed within the T. reesei genome, suggesting an epigenetic component in the regulation of conidiation. The significant upregulation of cellulases and hemicellulases during this process, and thus cellulase and hemicellulase content in the spores of T. reesei, contributes to the hypothesis that the ability to hydrolyze plant biomass is a major trait of this fungus enabling it to break dormancy and reinitiate vegetative growth after a period of facing unfavorable conditions.


Assuntos
Celulase/metabolismo , Proteínas Fúngicas/metabolismo , Trichoderma/fisiologia , Biomassa , Celulase/biossíntese , Celulase/genética , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Genoma , Glicosídeo Hidrolases/biossíntese , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Hifas , Análise de Sequência com Séries de Oligonucleotídeos , Espécies Reativas de Oxigênio , Esporos Fúngicos/enzimologia , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Transcrição Gênica , Trichoderma/enzimologia , Trichoderma/genética
16.
Biotechnol J ; 2(2): 201-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17294408

RESUMO

Metagenomics--the application of the genomics suit of technologies to uncultivated microorganisms--is coming of age. Sophisticated technologies are being developed and adapted to this promising genetic resource to make increasing use of the seemingly boundless molecular and functional diversity. Particular progress has been made in the areas of randomly proliferating limited-source DNA, massively parallel sequencing without cloning, isolating specific target sequences from highly complex template mixtures, high-throughput assay systems targeting metabolic pathways, artificial transcriptional regulators activating reporter genes to indicate enzymatic substrate conversion and cDNA cloning from extracted mRNA to directly clone actively expressed genes from a microbial consortium. However, challenges still lie ahead. Most prominently, the efficient heterologous expression of a plethora of potentially interesting enzymes from unknown source organisms is not readily achieved.


Assuntos
DNA Bacteriano/genética , Genética Microbiana/métodos , Genoma Bacteriano , Genômica/métodos , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Regulação Bacteriana da Expressão Gênica , Biblioteca Genômica , Análise de Sequência de DNA
17.
Biotechnol J ; 1(7-8): 815-21, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16897828

RESUMO

The chemical industry has an enormous need for innovation. To save resources, energy and time, currently more and more established chemical processes are being switched to biotechnological routes. This requires white biotechnology to discover and develop novel enzymes, biocatalysts and applications. Due to a limitation in the cultivability of microbes living in certain habitats, technologies have to be established which give access to the enormous resource of uncultivated microbial diversity. Metagenomics promises to provide new and diverse enzymes and biocatalysts as well as bioactive molecules and has the potential to make industrial biotechnology an economic, sustainable success.


Assuntos
Biotecnologia/métodos , Biotecnologia/tendências , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Genômica/métodos , Indústrias/métodos , Indústrias/tendências , Biodiversidade , Genômica/tendências
18.
Trends Biotechnol ; 23(12): 570-4, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16253362

RESUMO

Several predominantly political movements advocate white, or industrial, biotechnology as a means to alleviate economic, ecological and societal problems in petroleum-dependent industrialized nations worldwide. US and European approaches differ significantly and we believe that, in the long-term, only economic drivers will be able to bring about the broad use of renewable resources and a bio-based economy. As long as the cost of fossil fuel and feedstock for key chemicals have not passed their respective critical thresholds, industrial biotechnology and its products will need political support and funding, particularly in the energy and bulk-chemicals sectors. Other uses of industrial biotechnology, however, such as biocatalytic conversions of fine and specialty chemicals and the manufacture of high-value products, such as nutriceuticals, cosmeceuticals and performance chemicals offer dynamic growth opportunities both for established chemical industries, as well as emerging entrepreneurial enterprises.


Assuntos
Biotecnologia/tendências , Fontes de Energia Bioelétrica , Biotecnologia/métodos , Indústria Química/métodos , Indústria Química/tendências , União Europeia , Microbiologia Industrial/métodos , Microbiologia Industrial/tendências , Estados Unidos
19.
Nat Rev Microbiol ; 3(6): 510-6, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15931168

RESUMO

Different industries have different motivations to probe the enormous resource that is uncultivated microbial diversity. Currently, there is a global political drive to promote white (industrial) biotechnology as a central feature of the sustainable economic future of modern industrialized societies. This requires the development of novel enzymes, processes, products and applications. Metagenomics promises to provide new molecules with diverse functions, but ultimately, expression systems are required for any new enzymes and bioactive molecules to become an economic success. This review highlights industrial efforts and achievements in metagenomics.


Assuntos
Enzimas/genética , Genômica , Indústrias , Bactérias/enzimologia , Bactérias/genética , Biodiversidade , Catálise , Ecossistema , Plasmídeos/genética
20.
Curr Opin Biotechnol ; 13(6): 572-7, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12482516

RESUMO

Historically, biotechnology has missed up to 99% of existing microbial resources by using traditional screening techniques. Strategies of directly cloning 'environmental DNA' comprising the genetic blueprints of entire microbial consortia (the so-called 'metagenome') provide molecular sequence space that along with ingenious in vitro evolution technologies will act synergistically to bring a maximum of available sequence-space into biocatalytic application.


Assuntos
Bactérias/enzimologia , Bactérias/genética , Ecossistema , Enzimas/isolamento & purificação , Genoma Bacteriano , Bactérias/classificação , Catálise , Clonagem Molecular , Ativação Enzimática , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Biblioteca Genômica , Proteínas Recombinantes/isolamento & purificação
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