7 results on '"Alves, Joana I."'
Search Results
2. Enrichment of Anaerobic Syngas-Converting Communities and Isolation of a Novel Carboxydotrophic Acetobacterium wieringae Strain JM.
- Author
-
Arantes, Ana L., Moreira, João P. C., Diender, Martijn, Parshina, Sofiya N., Stams, Alfons J. M., Alves, M. Madalena, Alves, Joana I., and Sousa, Diana Z.
- Subjects
CARBON monoxide ,MULTIENZYME complexes ,SYNTHESIS gas ,YEAST extract ,CARBON compounds - Abstract
Syngas is a substrate for the anaerobic bioproduction of fuels and valuable chemicals. In this study, anaerobic sludge was used for microbial enrichments with synthetic syngas and acetate as main substrates. The objectives of this study were to identify microbial networks (in enrichment cultures) for the conversion of syngas to added-value products, and to isolate robust, non-fastidious carboxydotrophs. Enrichment cultures produced methane and propionate, this last one an unusual product from syngas fermentation. A bacterium closely related to Acetobacterium wieringae was identified as most prevalent (87% relative abundance) in the enrichments. Methanospirillum sp. and propionate-producing bacteria clustering within the genera Anaerotignum and Pelobacter were also found. Further on, strain JM, was isolated and was found to be 99% identical (16S rRNA gene) to A. wieringae DSM 1911
T . Digital DNA-DNA hybridization (dDDH) value between the genomes of strain JM and A. wieringae was 77.1%, indicating that strain JM is a new strain of A. wieringae. Strain JM can grow on carbon monoxide (100% CO, total pressure 170 kPa) without yeast extract or formate, producing mainly acetate. Remarkably, conversion of CO by strain JM showed shorter lag phase than in cultures of A. wieringae DSM 1911T , and about four times higher amount of CO was consumed in 7 days. Genome analysis suggests that strain JM uses the Wood-Ljungdahl pathway for the conversion of one carbon compounds (CO, formate, CO2 /H2 ). Genes encoding bifurcational enzyme complexes with similarity to the bifurcational formate dehydrogenase (Fdh) of Clostridium autoethanogenum are present, and possibly relate to the higher tolerance to CO of strain JM compared to other Acetobacterium species. A. wieringae DSM 1911T grew on CO in medium containing 1 mM formate. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
3. Comparative Analysis of Carbon Monoxide Tolerance among Thermoanaerobacter Species.
- Author
-
Alves, Joana I., Alves, M. Madalena, Plugge, Caroline M., Stams, Alfons J. M., and Sousa, Diana Z.
- Subjects
ACETOGENIUM kivui ,CARBON monoxide ,COMPARATIVE studies - Abstract
An anaerobic thermophilic strain (strain PCO) was isolated from a syngas-converting enrichment culture. Syngas components cannot be used by strain PCO, but the new strain is very tolerant to carbon monoxide (pCO = 1.7 × 105 Pa, 100% CO). 16S rRNA gene analysis and DNA-DNA hybridization revealed that strain PCO is a strain of Thermoanaerobacter thermohydrosulfuricus. The physiology of strain PCO and other Thermoanaerobacter species was compared, focusing on their tolerance to carbon monoxide. T. thermohydrosulfuricus, T. brockii subsp. finnii, T. pseudethanolicus, and T. wiegelii were exposed to increased CO concentrations in the headspace, while growth, glucose consumption and product formation were monitored. Remarkably, glucose conversion rates by Thermoanaerobacter species were not affected by CO. All the tested strains fermented glucose to mainly lactate, ethanol, acetate, and hydrogen, but final product concentrations differed. In the presence of CO, ethanol production was generally less affected, but H
2 production decreased with increasing CO partial pressure. This study highlights the CO resistance of Thermoanaerobacter species. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
4. Enrichment of anaerobic syngas-converting bacteria from thermophilic bioreactor sludge.
- Author
-
Alves, Joana I., Stams, Alfons J.M., Plugge, Caroline M., Madalena Alves, M., and Sousa, Diana Z.
- Subjects
- *
SYNTHESIS gas , *ANAEROBIC bacteria , *THERMOPHILIC microorganisms , *BIOREACTORS , *SLUDGE management , *MICROORGANISM populations - Abstract
Thermophilic (55 °C) anaerobic microbial communities were enriched with a synthetic syngas mixture (composed of CO, H2, and CO2) or with CO alone. Cultures T- Syn and T- CO were incubated and successively transferred with syngas (16 transfers) or CO (9 transfers), respectively, with increasing CO partial pressures from 0.09 to 0.88 bar. Culture T-Syn, after 4 successive transfers with syngas, was also incubated with CO and subsequently transferred (9 transfers) with solely this substrate - cultures T- Syn- CO. Incubation with syngas and CO caused a rapid decrease in the microbial diversity of the anaerobic consortium. T- Syn and T- Syn- CO showed identical microbial composition and were dominated by Desulfotomaculum and Caloribacterium species. Incubation initiated with CO resulted in the enrichment of bacteria from the genera Thermincola and Thermoanaerobacter. Methane was detected in the first two to three transfers of T-Syn, but production ceased afterward. Acetate was the main product formed by T- Syn and T- Syn- CO. Enriched T- CO cultures showed a two-phase conversion, in which H2 was formed first and then converted to acetate. This research provides insight into how thermophilic anaerobic communities develop using syngas/ CO as sole energy and carbon source can be steered for specific end products and subsequent microbial synthesis of chemicals. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
5. Propionate Production from Carbon Monoxide by Synthetic Cocultures of Acetobacterium wieringae and Propionigenic Bacteria.
- Author
-
Moreira, João P. C., Diender, Martijn, Arantes, Ana L., Boeren, Sjef, Stams, Alfons J. M., Alves, M. Madalena, Alves, Joana I., and Sousa, Diana Z.
- Subjects
- *
CARBON monoxide , *AMINO acid metabolism , *PROPIONATES - Abstract
Gas fermentation is a promising way to convert CO-rich gases to chemicals. We studied the use of synthetic cocultures composed of carboxydotrophic and propionigenic bacteria to convert CO to propionate. So far, isolated carboxydotrophs cannot directly ferment CO to propionate, and therefore, this cocultivation approach was investigated. Four distinct synthetic cocultures were constructed, consisting of Acetobacterium wieringae (DSM 1911T) and Pelobacter propionicus (DSM 2379T), Ac. wieringae (DSM 1911T) and Anaerotignum neopropionicum (DSM 3847T), Ac. wieringae strain JM and P. propionicus (DSM 2379T), and Ac. wieringae strain JM and An. neopropionicum (DSM 3847T). Propionate was produced by all the cocultures, with the highest titer (;24mM) being measured in the coculture composed of Ac. wieringae strain JM and An. neopropionicum, which also produced isovalerate (;4mM), butyrate (;1mM), and isobutyrate (0.3mM). This coculture was further studied using proteogenomics. As expected, enzymes involved in the Wood-Ljungdahl pathway in Ac. wieringae strain JM, which are responsible for the conversion of CO to ethanol and acetate, were detected; the proteome of An. neopropionicum confirmed the conversion of ethanol to propionate via the acrylate pathway. In addition, proteins related to amino acid metabolism and stress response were highly abundant during cocultivation, which raises the hypothesis that amino acids are exchanged by the two microorganisms, accompanied by isovalerate and isobutyrate production. This highlights the importance of explicitly looking at fortuitous microbial interactions during cocultivation to fully understand coculture behavior. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
6. Bioelectrochemical systems (BESs) towards conversion of carbon monoxide/syngas: A mini-review.
- Author
-
Barbosa, Sónia G., Peixoto, Luciana, Alves, Joana I., and Alves, M. Madalena
- Subjects
- *
CARBON monoxide , *ACETATES , *ELECTRON donors , *ELECTRIC circuits , *SYNTHESIS gas , *BIOMASS gasification , *ELECTROPHILES - Abstract
Microbial conversion of carbon monoxide (CO)/syngas has been extensively investigated. The microbial conversion of CO/syngas offers numerous advantages over chemically catalyzed processes e.g. the specificity of the biocatalysts, the operation at ambient conditions and high conversion efficiencies. Bioelectrochemical systems (BESs) exploit the capacity of electrochemically active bacteria (EAB) to use insoluble electron acceptors or donors to produce electricity or added-value compounds. Electricity production from different organic sources in BESs has been broadly demonstrated, whereas electricity production from CO/syngas has been very little reported. Acetate oxidation by a consortium of carboxydotrophic and CO-tolerant EAB has been suggested to be the main pathway responsible for indirect electricity generation from CO/syngas. Although electricity production in BESs from several organic sources has been widely investigated, the interest on BESs research is currently moving to the production of added-value compounds by electro-fermentation (EF) processes. EF allows to modify redox balances by the use of electric circuits to fine tune metabolic pathways towards obtaining products with high economic value. Although EF has been widely studied, the potential of use CO-rich gas streams as substrate has been under explored. This review presents and discusses current advances on microbial conversion of CO/syngas in BESs. • Bioelectrochemical systems have been proposed for microbial conversion of syngas. • Syngas conversion relies on a consortium of CO-tolerant EAB and carboxydotrophs. • Acetate oxidation seems to be the main pathway for indirect electricity production. • Acetate has been reported as the main product of syngas electro-fermentation. • Syngas electro-fermentation is a promising strategy to obtain compounds of interest. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
7. Fermentação de gás de síntese por Clostridium carboxidivorans
- Author
-
Roque, Lúcia Manuela Antunes, Alves, Joana I., Alves, M. M., and Universidade do Minho
- Subjects
CO partial pressure ,Pressão parcial de CO ,Butanol ,Temperature ,Biotecnologia Ambiental [Engenharia e Tecnologia] ,Temperatura ,Syngas ,Clostridium carboxidivorans ,Engenharia e Tecnologia::Biotecnologia Ambiental - Abstract
Dissertação de mestrado em Biotecnologia, Global energy demands and environmental concerns are accelerating the development of renewable energy sources and promoting the replacement of conventional manufacturing processes. In this context, low-biodegradable materials assume a huge importance since it serves as the feedstock for these new bio-based processes. Gasification is an alternative technology for biomass and wastes treatment, and originates a carbon-rich gas (called syngas, mainly composed of carbon monoxide (CO), carbon dioxide (CO2) and hydrogen (H2)), which can be further converted into a large spectrum of chemicals and fuels. Syngas fermentation uses microorganisms as biocatalysts to assimilate 1-carbon molecules and produce value-added compounds, such as acetic and n-butyric acids, ethanol, butanol, among others. Butanol has emerged as a high valuable compound for the chemical and energy industries due to its characteristics (higher energy content, lower toxicity, among others). Although it is nowadays produced from petrochemical processes, some acetogens can produce it from syngas fermentation. From the previous, Clostridium carboxidivorans is considered a promising species for industrial application due to its unique capacity of producing higher alcohols (butanol and hexanol) from syngas at specific experimental conditions. The first part of this thesis focused on the physiological characterization of C. carboxidivorans when converting different substrates (glucose, syngas and CO) and the dependence of yeast extract as a co-factor during syngas fermentation. The second part aimed to evaluate different operational strategies to promote alcohol production (specially butanol): cultivation at sub-optimal temperature and testing different CO partial pressures within the syngas mixture. The main results and conclusions from this thesis are: 1) the versatility of C. carboxidivorans, as it grew well in all the conditions tested, showing no inhibition when cultivated at different temperatures (30 and 37 ºC), pressures (100, 170 and 200 kPa), different gaseous substrates and even in the absence of yeast extract; it was also shown that a higher CO concentration was crucial for n-butyric acid synthesis and that yeast extract is important to accelerate growth but do not influence acetic acid titers; 2) regarding the strategies to promote solventogenesis, the use of above-atmospheric pressures showed to be more promising than cultivation at 30 ºC, since higher pressures (170 and 200 kPa) lead to an increase in CO consumption rate and accelerated n-butyric acid synthesis, which suggests the microorganism was following the metabolic pathway that further leads to butanol production., O crescimento económico e as alterações climáticas têm promovido o desenvolvimento das energias renováveis e de novos processos biotecnológicos. Os resíduos (biomassa e resíduos urbanos) constituem a matéria–prima necessária para esta transição. A gaseificação é uma tecnologia utilizada no tratamento de resíduos, cujo produto final é um gás rico em carbono (monóxido de carbono (CO) e dióxido de carbono (CO2)) e hidrogénio (H2), denominado gás de síntese (ou syngas) que pode ser convertido em vários compostos de elevado interesse económico. A fermentação de syngas recorre à capacidade de certos microrganismos para utilizar estes gases e convertê-los em compostos de valor acrescentado, como os ácidos acético e n-butírico, etanol, butanol, entre outros. O butanol, por exemplo, tem elevado valor para a indústria química e para o sector da energia, devido às suas características (elevado conteúdo energético, baixa toxicidade, entre outros). Apesar de ser atualmente produzido por processos petroquímicos, alguns microrganismos têm a capacidade de o produzir a partir da fermentação de syngas. A espécie Clostridium carboxidivorans destaca-se devido à sua capacidade única de produzir álcoois de maior peso molecular (butanol e hexanol) a partir de syngas em condições operacionais específicas. A primeira parte desta tese focou-se na caracterização fisiológica de C. carboxidivorans na conversão de diferentes substratos (glucose, syngas e CO), bem como na dependência do extrato de levedura como co-factor de crescimento, durante a fermentação de syngas. A segunda parte teve como objetivo estudar estratégias operacionais para promover a produção de álcoois (ex. butanol): temperatura e pressão. Os principais resultados e conclusões são: 1) a versatilidade de C. carboxidivorans, dado ter crescido em todas as condições testadas, não mostrando inibição do crescimento quando cultivado a diferentes temperaturas (30 e 37 ºC), pressões (100, 170 e 200 kPa), misturas gasosas e mesmo na ausência de extrato de levedura no meio de cultura; verificou-se também que uma concentração de CO superior na mistura gasosa foi crucial para a síntese de ácido n-butírico e que o extrato de levedura é importante para acelerar o crescimento, mas não influencia a produção de ácido acético; 2) quanto às diferentes estratégias estudadas, a utilização de pressões superiores (> 100 kPa) mostrou ser mais promissora do que alterar a temperatura de fermentação, pois pressões mais elevadas (170 e 200 kPa) levaram a um aumento da taxa de consumo de CO e produção de ácido n-butírico, o que sugere que o microrganismo estaria a seguir a via metabólica que originará butanol.
- Published
- 2021
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.