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1.
J Agric Food Chem ; 67(38): 10685-10693, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31479251

RESUMO

Theanine is the most abundant non-protein amino acid in Camellia sinensis, but it is not known how a tea plant accumulates such high levels of theanine. The endophyte isolated from in vitro grown plantlets of C. sinensis cultivars was identified as Luteibacter spp., showing strong biocatalytic activity for converting both glutamine and ethylamine to theanine. Theanine was secreted outside of the bacteria. The endophyte isolated from in vitro plantlets of Camellia oleifera cultivar was identified as Bacillus safensis and did not convert glutamine and ethylamine to theanine. Enzymatic assays in vitro indicated that γ-glutamyltranspeptidases rCsEGGTs from the endophyte Luteibacter strains converted glutamine and ethylamine to theanine at higher rates than rCsGGTs from C. sinensis. This is the first report on theanine biosynthesis by an endophyte from C. sinensis, which provides a new pathway to explore the mechanism of theanine biosynthesis in C. sinensis and the interactions between an endophyte and tea plants.


Assuntos
Bactérias/metabolismo , Camellia sinensis/microbiologia , Endófitos/metabolismo , Glutamatos/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Camellia sinensis/química , Camellia sinensis/classificação , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Etilaminas/metabolismo , Glutamina/metabolismo , Folhas de Planta/química , Folhas de Planta/microbiologia
2.
J Environ Radioact ; 208-209: 106035, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499317

RESUMO

The paper continues study of exposures of luminous marine bacteria to low-dose radiation of tritium; tritiated water (HTO) was applied as a source of the irradiation. Hypothesis on involvement of Reactive Oxygen Species (ROS) to signaling mechanism of bacterial cells under exposure to low-intensity tritium radiation was verified. Bacterial bioluminescence intensity was considered as a tested physiological parameter; it was compared to the ROS production in the bacterial environment of different activity concentrations: 0.03, 4.0, and 500 MBq/L. Exposure of the bacteria to chronic low-dose tritium irradiation (<0.08 Gy) increased bioluminescence intensity and ROS production considerably (up to 300%). Spearman rank correlation coefficients were calculated and confirmed relations between the bioluminescence intensity and ROS production. Additional peculiarities of HTO effect were: independence of the bioluminescence intensity and ROS content on HTO activity concentration; low ROS content in bacteria-free aquatic environment. Effects of HTO on bacterial bioluminescence were attributed to: (1) trigger function of tritium decay products in the bacterial metabolic oxygen-dependent processes, with bioluminescence involved; (2) signaling role of ROS as intercellular messengers in "bystander effect"; (3) fixed amount of bacterial cells (3•107 cells/mL) provided the upper limits of the bioluminescence intensity and ROS content. As an outlook, in spite of low energy of tritium decay, its influence on aquatic biota via ROS production by microorganisms should be taken into consideration.


Assuntos
Bactérias/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Trítio/toxicidade , Poluentes Radioativos da Água/toxicidade , Bactérias/metabolismo , Relação Dose-Resposta à Radiação , Microbiologia da Água
3.
World J Microbiol Biotechnol ; 35(8): 130, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385043

RESUMO

Bacterial biofilms (BFs) are membrane-like structures formed by the secretion of extracellular polymeric substances (EPS) by bacteria. The formation of BFs contributes to bacterial survival and drug resistance. When bacteria proliferate, they produce secondary metabolites that act as signaling molecules in bacterial communities that regulate intracellular and cell-to-cell communication. This communication can directly affect the physiological behavior of bacteria, including the production and emission of light (bioluminescence), the expression of virulence factors, the resistance to antibiotics, and the shift between planktonic and biofilm lifestyles. We review the major signaling molecules that regulate BF formation, with a focus on quorum-sensing systems (QS), cyclic diguanylate (c-di-GMP), two-component systems (TCS), and small RNA (sRNA). Understanding these processes will lead to new approaches for treating chronic diseases and preventing bacterial resistance.


Assuntos
Bactérias/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Transdução de Sinais , Bactérias/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Percepção de Quorum , RNA Bacteriano/metabolismo , Pequeno RNA não Traduzido/metabolismo
4.
World J Microbiol Biotechnol ; 35(9): 131, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432251

RESUMO

Cholesterol is a C27-sterol employed as starting material for the synthesis of valuable pharmaceutical steroids and precursors. The microbial transformations of cholesterol have been widely studied, since they are performed with high regio- and stereoselectivity and allow the production of steroidal compounds which are difficult to synthesize by classical chemical methods. In recent years, ongoing research is being conducted to discover novel biocatalysts and to develop biotechnological processes to improve existing biocatalysts and biotransformation reactions. The main objective of this review is to present the most remarkable advances in fungal and bacterial transformation of cholesterol, focusing on the different types of microbial reactions and biocatalysts, biotransformation products, and practical aspects related to sterol dispersion improvement, covering literature since 2000. It reviews the conversion of cholesterol by whole-cell biocatalysts and by purified enzymes that lead to various structural modifications, including side chain cleavage, hydroxylation, dehydrogenation/reduction, isomerization and esterification. Finally, approaches used to improve the poor solubility of cholesterol in aqueous media, such as the use of different sterol-solubilizing agents or two-phase conversion system, are also discussed.


Assuntos
Bactérias/metabolismo , Biotecnologia/métodos , Colesterol/metabolismo , Fungos/metabolismo , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Biotecnologia/tendências , Biotransformação , Enzimas/metabolismo , Fungos/genética , Fungos/crescimento & desenvolvimento
5.
World J Microbiol Biotechnol ; 35(9): 132, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432260

RESUMO

This paper aims to characterize halophilic bacteria inhabiting Algerian Saline Ecosystems (Sebkha and Chott) located in arid and semi-arid ecoclimate zones (Northeastern Algeria). In addition, screening of enzymatic activities, heavy metal tolerance and antagonistic potential against phytopathogenic fungi were tested. A total of 74 bacterial isolates were screened and phylogenetically characterized using 16S rRNA gene sequencing. The results showed a heterogeneous group of microorganisms falling within two major phyla, 52 strains belonging to Firmicutes (70.2%) and 22 strains (30.8%) of γ-Proteobacteria. In terms of main genera present, the isolates were belonging to Bacillus, Halobacillus, Lentibacillus, Oceanobacillus, Paraliobacillus, Planomicrobium, Salicola, Terribacillus, Thalassobacillus, Salibacterium, Salinicoccus, Virgibacillus, Halomonas, Halovibrio, and Idiomarina. Most of the enzymes producers were related to Bacillus, Halobacillus, and Virgibacillus genera and mainly active at 10% of growing salt concentrations. Furthermore, amylase, esterase, gelatinase, and nuclease activities ranked in the first place within the common hydrolytic enzymes. Overall, the isolates showed high minimal inhibitory concentration values (MIC) for Ni2+ and Cu2+ (0.625 to 5 mM) compared to Cd2+ (0.1 to 2 mM) and Zn2+ (0.156 to 2 mM). Moreover, ten isolated strains belonging to Bacillus, Virgibacillus and Halomonas genera, displayed high activity against the pathogenic fungi (Botrytis cinerea, Fusarium oxyporum, F. verticillioides and Phytophthora capsici). This study on halophilic bacteria of unexplored saline niches provides potential sources of biocatalysts and novel bioactive metabolites as well as promising candidates of biocontrol agents and eco-friendly tools for heavy metal bioremediation.


Assuntos
Antibiose , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biota , Microbiologia Ambiental , Salinidade , Argélia , Bactérias/classificação , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fungos/crescimento & desenvolvimento , Hidrolases/análise , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Testes de Sensibilidade Microbiana , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Dokl Biochem Biophys ; 486(1): 216-219, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31367825

RESUMO

The direct action of singlet oxygen on the bacteriochlorophyll (BChl) of light-harvesting complexes in the membranes of four species of purple non-sulfur and sulfur photosynthesizing bacteria with and without carotenoids was studied. It was found that BChl in carotenoidless samples is generally more resistant to the action of singlet oxygen compared to the control. It is assumed that carotenoids are not required to protect BChl of bacterial light-harvesting complexes from singlet oxygen, and in the classic work by Griffith et al. [1] the apoptosis process in carotenoidless mutant cells, which involves the destruction of complexes, the appearance of monomeric BChl, and the generation of singlet oxygen caused by BChl, followed by BChl oxidation, was mistakenly attributed to the protective function of carotenoids.


Assuntos
Bactérias/citologia , Bactérias/metabolismo , Bacterioclorofilas/metabolismo , Carotenoides/metabolismo , Membrana Celular/metabolismo , Fotossíntese , Oxigênio Singlete/metabolismo , Estresse Oxidativo
7.
An Acad Bras Cienc ; 91(suppl 3): e20190252, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365611

RESUMO

The various descriptors of biochemical diversity and an evaluation of its status of knowledge are briefly outlined. Using a few examples from in house research projects, I illustrate strategies used to increase this knowledge. Because bacteria represent an extremely diverse domain of life and carry out the widest known range of biochemical transformations, this mini-review focusses on bacteria.


Assuntos
Bactérias , Bactérias/química , Bactérias/genética , Bactérias/metabolismo
8.
Pestic Biochem Physiol ; 158: 88-100, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378365

RESUMO

Methyl halide group of pesticides are being used widely in past decades as fumigant but due to their hazardous effect, these pesticides are not sold directly. They are volatile and gaseous in nature and may easily come in the contact of trophosphere and stratosphere. In troposphere, they are harmful to the living beings; nevertheless, in stratosphere they react with ozone and degrade the ozone layers. In this study, we have investigated the in-silico pathways of methyl halide and its toxic effect on living systems like pest, humans and environment. Till date, limited studies provide the understanding of degradation of methyl halide and its effect on the environment. This leads to availability of scanty information for overall bio-magnifications of methyl halides at molecular and cellular level. The model developed in the present study explains how a volatile toxic compound not only affects living systems on earth but also on environmental layers. Hub nodes were also evaluated by investigating the developed model topologically. Methyl transferase system is identified as promising enzyme in response to degradation of methyl halides.


Assuntos
Bactérias/metabolismo , Cloreto de Metila/metabolismo , Biodegradação Ambiental , Biologia de Sistemas
9.
An Acad Bras Cienc ; 91(2): e20180394, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31269105

RESUMO

The petrochemical industry has played a considerable role in generation and release of waste in the environment. Activated sludge and facultative lagoons are commonly used for domestic and industrial wastewater treatment due to their low-cost and minimal need for operational requirements. Microorganisms present in wastewater treatment plant (WWTP) are responsible for most nutrient removal. In this study, microbiological and physicochemical parameters were used to estimate changes in bacterial community in a petrochemical industrial WWTP. The activated sludge was the place with higher heterotrophic bacterial quantification. Denitrifying bacteria was reduced at least 5.3 times throughout all collections samples. We observe a decrease in the total Kjeldahl nitrogen, oxygen demand and phosphate throughout the WWTP. In this work, we also use Matrix-Assisted Laser Desorption Ionisation-Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for bacteria isolates identification comparing with 16S rDNA sequencing. The MALDI-TOF MS allowed the identification of 93% of the isolates and only 5% show different results from 16S rDNA sequencing showing that the MALDI-TOF MS can be a tool for identifying environmental bacteria. The observation of microbial community dynamics in the WWTP is important in order to understand the functioning of the ecological structure formed in a specific environment.


Assuntos
Bactérias/metabolismo , Águas Residuárias/química , Águas Residuárias/microbiologia , Purificação da Água/métodos , Bactérias/classificação , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Espectrometria de Massas , Indústria de Petróleo e Gás , RNA Ribossômico 16S/genética , Eliminação de Resíduos Líquidos/métodos
10.
J Basic Microbiol ; 59(8): 775-783, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31259432

RESUMO

We unearthed some interesting microecological discoveries while selecting for the most beneficial bacterial strains to be used as probiotics in Lecane inermis rotifer mass culture. For 3 years, we maintained the cultures of L. inermis, with selection for the highest growth rate and resistance to potential contamination. Then, we conducted further selection and isolation in two groups: rotifers inoculated with the bacterial consortium isolated from the rotifer cultures, and rotifers fed with a commercial bioproduct. Selection was conducted in demanding conditions, with particulate matter suspended in spring water as a substrate, without aeration and under strong consumer pressure, and led to selection of two cultivable strains isolated from the optimal rotifers culture. According to molecular analysis, these strains were Aeromonas veronii and Pseudomonas mosselii. Biolog® ECO plate tests showed that both investigated bacterial communities metabolized wide but similar range of substrates. Therefore, intensely selective conditions led to considerable reduction in bacterial community regarding taxonomy, but not in metabolic activity, showing a functional composition decoupling. Aside from this result, our novel selection method dedicated to the sustainable culture of two trophic levels, a directed selection procedure (DSC), could potentially lead to the development of biotechnologically valuable strains with high metabolic activity and the ability to metabolize different sorts of substrate without harmful impact on higher trophic levels.


Assuntos
Biodiversidade , Consórcios Microbianos , Rotíferos/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Meios de Cultura/metabolismo , Nutrientes/metabolismo , Filogenia , Rotíferos/crescimento & desenvolvimento , Esgotos/microbiologia
11.
J Agric Food Chem ; 67(28): 7898-7907, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282664

RESUMO

This study aimed to explore the effects of silencing HB12 and TT8 genes on protein utilization characteristics of alfalfa. Ground samples of 11 HB12-silenced (HB12i), 5 TT8-silenced (TT8i) and 4 wild type (WT) were incubated in a Daisy II incubator with N15 labeled ammonium sulfate for 0, 4, 8, 12, and 24 h. CP degradation and degradational kinetics, microbial nitrogen fractions, and protein metabolic profiles were determined. Moreover, relationships between protein profiles and FTIR spectral parameters were estimated. Results showed that transgenic alfalfa had lower CP degradation, microbial protein, and total available protein compared with WT, especially for HB12i. In addition, CP degradation and protein metabolic profiles were closely correlated with FTIR spectral parameters and thereby could be predicted from spectral parameters. In conclusion, silencing of HB12 and TT8 genes in alfalfa decreased protein degradational and metabolic profiles, which were predictable with FTIR spectral parameters.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Inativação Gênica , Proteínas de Homeodomínio/genética , Medicago sativa/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rúmen/metabolismo , Ração Animal/análise , Animais , Bactérias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bovinos , Digestão , Proteínas de Homeodomínio/metabolismo , Cinética , Medicago sativa/química , Medicago sativa/metabolismo , Proteínas de Plantas/química , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteólise , Rúmen/química , Rúmen/microbiologia
12.
J Agric Food Chem ; 67(28): 7869-7879, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31287296

RESUMO

Carnitine, a dietary quaternary amine mainly from red meat, is metabolized to trimethylamine (TMA) by gut microbiota and subsequently oxidized to trimethylamine-N-oxide (TMAO) by host hepatic enzymes, flavin monooxygenases (FMOs). The objective of this study aims to investigate the effects of flavonoids from oolong tea and citrus peels on reducing TMAO formation and protecting vascular inflammation in carnitine-feeding mice. The results showed that mice treated with 1.3% carnitine in drinking water significantly (p < 0.05) increased the plasma levels of TMAO compared to control group, whereas the plasma TMAO was remarkedly reduced by flavonoids used. Meanwhile, these dietary phenolic compounds significantly (p < 0.05) decreased hepatic FMO3 mRNA levels compared to carnitine only group. Additionally, oolong tea extract decreased mRNA levels of vascular inflammatory markers such as tissue necrosis factor-alpha (TNF-α), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Polymethoxyflavones significantly lowered the expression of VCAM-1 and showed a decreasing trend in TNF-α and E-selectin mRNA expression compared to the carnitine group. Genus-level analysis of the gut microbiota in the cecum showed that these dietary phenolic compounds induced an increase in the relative abundances of Bacteroides. Oolong tea extract-treated group up-regulated Lactobacillus genus, compared to the carnitine only group. Administration of polymethoxyflavones increased Akkermansia in mice.


Assuntos
Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Camellia sinensis/química , Carnitina/metabolismo , Citrus/química , Flavonas/administração & dosagem , Extratos Vegetais/administração & dosagem , Animais , Aterosclerose/genética , Aterosclerose/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biotransformação/efeitos dos fármacos , Feminino , Flavonas/análise , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Metilaminas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/análise , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
13.
J Agric Food Chem ; 67(31): 8493-8499, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31310523

RESUMO

The ginsenosides Rh2 and Rg3 induce tumor cell apoptosis, inhibit tumor cell proliferation, and restrain tumor invasion and metastasis. Despite Rh2 and Rg3 having versatile pharmacological activities, contents of them in natural ginseng are extremely low. To produce ginsenosides Rh2 and Rg3, the saponin-producing capacity of endophytic bacteria isolated from Panax ginseng was investigated. In this work, 81 endophytic bacteria isolates were taken from ginseng roots by tissue separation methods. Among them, strain PDA-2 showed the highest capacity to produce the rare ginsenosides; the concentrations of rare ginsenosides Rg3 and Rh2 reached 62.20 and 18.60 mg/L, respectively. On the basis of phylogenetic analysis, it was found that strain PDA-2 belongs to the genus Agrobacterium and was very close to Agrobacterium rhizogenes.


Assuntos
Bactérias/metabolismo , Endófitos/metabolismo , Ginsenosídeos/biossíntese , Panax/microbiologia , Agrobacterium/classificação , Agrobacterium/genética , Agrobacterium/isolamento & purificação , Agrobacterium/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Filogenia , Raízes de Plantas/microbiologia
14.
Bioresour Technol ; 289: 121703, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31271912

RESUMO

Feasibility of combined lysozyme and rhamolipid (RL) pretreatment on the enhancement of excess sludge (ES) hydrolysis and decomposition was assessed in this study. Results showed lysozyme and RL combined treatment could significantly promote ES hydrolysis and decomposition, an additional 1196.9 mg/L soluble chemical oxygen demand (SCOD), 792.5 mg/L protein and 133.5 mg/L polysaccharide were released compared with the sum of sole RL and sole lysozyme treatment at the optimal RL dosage of 0.3 g/gSS and lysozyme dosage of 0.15 g/gSS after 8 h co-digestion. 45.3% bacteria and 84.5% archaea decomposition degree were gained under the combined treatment at the optimal RL dosage. Class Gammaproteobacteria and genus Methanothrix were the predominant bacteria and archaea with the relative abundance of 72.4% and 60.8%, respectively. After the combined pretreatment, ES was beneficial for volatile fatty acids accumulation and acetic acid dependent methane generating inferred from the results of microbial community composition.


Assuntos
Glicolipídeos/metabolismo , Muramidase/metabolismo , Esgotos/microbiologia , Archaea/metabolismo , Bactérias/metabolismo , Análise da Demanda Biológica de Oxigênio , Ácidos Graxos Voláteis/biossíntese , Hidrólise , Metano/metabolismo , Microbiota
15.
Water Sci Technol ; 79(11): 2036-2045, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31318341

RESUMO

To obtain a bacterial consortium that can degrade azo dyes effectively, a bacterial consortium was enriched that can degrade Metanil yellow effectively. After 6 h, 96.25% Metanil yellow was degraded under static conditions by the bacterial consortium, which was mainly composed of Pseudomonas, Lysinibacillus, Lactococcus, and Dysgonomonas. In particular, Pseudomonas played a main role in the decolorization process. Co-substrate increased the decolorization rate, and yeast powder, peptone, and urea demonstrated excellent effects. The optimal pH value and salinity for the decolorization of azo dyes is 4-7 and 1% salinity respectively. The bacterial consortium can directly degrade many azo dyes, such as direct fast black G and acid brilliant scarlet GR. Azo reductase activity, laccase activity, and lignin peroxidase activity were estimated as the key reductase for decolorization, and Metanil yellow can be degraded into less toxic degradation products through synergistic effects. The degradation pathway of Metanil yellow was analyzed by Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry, which demonstrated that Metanil yellow was cleaved at the azo bond, producing p-aminodiphenylamine and diphenylamine. These findings improved our knowledge of azo-dye-decolorizing microbial resources and provided efficient candidates for the treatment of dye-polluted wastewaters.


Assuntos
Compostos Azo , Bactérias/metabolismo , Biodegradação Ambiental , Corantes , Águas Residuárias
16.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2266-2273, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359652

RESUMO

A high-content GABA was found in Sojae Semen Praeparatum(SSP), which is a famous traditional Chinese medicine and officially listed in Chinese Pharmacopoeia. To screen out and identify GABA-producing microbes from samples at different time points during the fermenting process of SSP, traditional microbiological methods combined with molecular biological methods were used to study the predominant GABA-producing microorganisms existing in the fermenting process of SSP. This study would lay a foundation for further studying the processing mechanism of SSP. The fermenting process of SSP was based on Chinese Pharmacopoeia(2010 edition), and samples were taken at different time points during the fermenting process of SSP. The bacteria and fungi from samples at different time points in the fermenting process of SSP were cultured, isolated and purified by selective medium, and dominant strains were selected. The dominant bacteria were cultured in the designated liquid medium to prepare the fermentation broths, and GABA in the fermentation broth was qualitatively screened out by thin-layer chromatography. The microbial fermentation broth with GABA spots in the primary screening was quantitatively detected by online pre-column derivatization and high performance liquid chromatography established in our laboratory. GABA-producing microorganisms were screened out from predominant strains, and their GABA contents in fermentation broth were determined. The DNA sequences of GABA-producing bacteria and fungi were amplified using 16S rDNA and 18S rDNA sequences by PCR respectively. The amplified products were sequenced, and the sequencing results were identified through NCBI homology comparison. Molecular biological identification was made by phylogenetic tree constructed by MEGA 7.0 software. Through the homology comparison of NCBI and the construction of phylogenetic tree by MEGA 7.0 software, nine GABA-producing microorganisms were screened out and identified in this study. They were Bacillus subtilis, Enterococcus faecium, E. avium, Aspergillus tamarii, A. flavus, A. niger, Cladosporium tenuissimum, Penicillium citrinum and Phanerochaete sordida respectively. For the first time, nine GABA-producing microorganisms were screened out and identified in the samples at different time points during the fermenting process of SSP in this study. The results indicated that multiple predominant GABA-producing microorganisms exist in the fermenting process of SSP and may play an important role in the formation of GABA.


Assuntos
Bactérias/classificação , Fermentação , Fungos/classificação , Sementes/microbiologia , Soja/microbiologia , Ácido gama-Aminobutírico/biossíntese , Bactérias/metabolismo , Cromatografia Líquida de Alta Pressão , Fungos/metabolismo , Filogenia
17.
World J Microbiol Biotechnol ; 35(7): 107, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31267318

RESUMO

Marine microbial diversity offers enormous potential for discovery of compounds of crucial importance in healthcare, food security and bioindustry. However, access to it has been hampered by the difficulty of accessing and growing the organisms for study. The discovery and exploitation of marine bioproducts for research and commercial development requires state-of-the-art technologies and innovative approaches. Technologies and approaches are advancing rapidly and keeping pace is expensive and time consuming. There is a pressing need for clear guidance that will allow researchers to operate in a way that enables the optimal return on their efforts whilst being fully compliant with the current regulatory framework. One major initiative launched to achieve this, has been the advent of European Research Infrastructures. Research Infrastructures (RI) and associated centres of excellence currently build harmonized multidisciplinary workflows that support academic and private sector users. The European Marine Biological Research Infrastructure Cluster (EMBRIC) has brought together six such RIs in a European project to promote the blue bio-economy. The overarching objective is to develop coherent chains of high-quality services for access to biological, analytical and data resources providing improvements in the throughput and efficiency of workflows for discovery of novel marine products. In order to test the efficiency of this prototype pipeline for discovery, 248 rarely-grown organisms were isolated and analysed, some extracts demonstrated interesting biochemical properties and are currently undergoing further analysis. EMBRIC has established an overarching and operational structure to facilitate the integration of the multidisciplinary value chains of services to access such resources whilst enabling critical mass to focus on problem resolution.


Assuntos
Produtos Biológicos , Biotecnologia , Oceanos e Mares , Água do Mar/microbiologia , Organismos Aquáticos/genética , Organismos Aquáticos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , Descoberta de Drogas , Fungos/genética , Fungos/metabolismo , Metabolômica
18.
Nat Commun ; 10(1): 2472, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171781

RESUMO

The evolution of microbial and viral organisms often generates clonal interference, a mode of competition between genetic clades within a population. Here we show how interference impacts systems biology by constraining genetic and phenotypic complexity. Our analysis uses biophysically grounded evolutionary models for molecular phenotypes, such as fold stability and enzymatic activity of genes. We find a generic mode of phenotypic interference that couples the function of individual genes and the population's global evolutionary dynamics. Biological implications of phenotypic interference include rapid collateral system degradation in adaptation experiments and long-term selection against genome complexity: each additional gene carries a cost proportional to the total number of genes. Recombination above a threshold rate can eliminate this cost, which establishes a universal, biophysically grounded scenario for the evolution of sex. In a broader context, our analysis suggests that the systems biology of microbes is strongly intertwined with their mode of evolution.


Assuntos
Bactérias/genética , Evolução Biológica , Dobramento de Proteína , Estabilidade Proteica , Vírus/genética , Bactérias/metabolismo , Evolução Molecular , Aptidão Genética , Fenótipo , Recombinação Genética , Seleção Genética , Biologia de Sistemas , Vírus/metabolismo
19.
Plant Foods Hum Nutr ; 74(3): 383-390, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31228035

RESUMO

Orange juice is an important source of flavanones in the Western diet. However, little is known of the variation in flavanone content of shop-bought orange juice with pulp (OJP) or without pulp (OJ), nor the impact of pulp on the fate of flavanones in the gut. Total phenols, total flavonoids, antioxidant capacity, hesperidin and narirutin, and dietary fibre were measured in six orange juice brands sold as OJP and OJ. The inclusion of pulp had little impact on fibre content. Apart from total phenols (OJ: 208.4 ± 10.7 µg gallic acid equivalents (GAE) ml-1; OJP: 225.9 ± 16.7 µg GAE ml-1, P < 0.05), there were no differences between OJ and OJP. The fate of flavanones in OJ and OJP (Tropicana) were further compared using in vitro gastrointestinal (GI) models. After in vitro upper GI digestion, recovery of hesperidin was higher in OJ compared with OJP (89 ± 6 vs. 68 ± 3%, P = 0.033). After 2 h colonic fermentation, hesperidin was 1.2 fold higher in OJP than OJ. However, after 24 h colonic fermentation there was no significant difference between juices in terms of hesperidin, hesperetin, narirutin, naringenin and catabolites. In conclusion, the amount of pulp included in these shop-bought orange juices had little impact on flavanone metabolism in models of the GI tract. The effects of greater amounts of orange pulp remain to be determined.


Assuntos
Antioxidantes/análise , Citrus sinensis/química , Flavanonas/análise , Flavonoides/análise , Sucos de Frutas e Vegetais/análise , Fenóis/análise , Bactérias/metabolismo , Fibras na Dieta/análise , Digestão , Dissacarídeos/análise , Fermentação , Flavanonas/metabolismo , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Hesperidina/análise , Humanos
20.
Mar Pollut Bull ; 142: 309-314, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232308

RESUMO

The aim of the study was the investigation of bacterial diversity from sediments collected at Santos Estuarine System, regarding to their abilities for hexadecane biotransformation. Hexadecane is a medium-chain linear alkane, considered as a model molecule for hydrocarbon biodegradation studies. It is a component from aliphatic fraction of crude petroleum, commonly related to environmental contamination by diesel oil. Santos Basin is an area with historical petroleum contamination. In the present work, sediment samples from this area were inoculated in artificial seawater (ASW), containing hexadecane as carbon source. Six bacterial isolates were selected as resistant to hexadecane. Chromatographic results showed biodegradation indexes above 97%. After 48 h of culture, five of them could degrade >80% of the initial hexadecane added. These isolates were characterized by 16S rDNA gene sequencing analysis. The following species were found: Bacillus amyloliquefaciens, Staphylococcus epidermidis, Micrococcus luteus, Nitratireductor aquimarinus, and Bacillus pumilus.


Assuntos
Alcanos/metabolismo , Bactérias/isolamento & purificação , Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Bactérias/genética , Biodegradação Ambiental , DNA Ribossômico , Gasolina , Petróleo/metabolismo , Poluição por Petróleo , Água do Mar/microbiologia , Poluentes Químicos da Água/metabolismo
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