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1.
Food Chem ; 400: 134001, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36084586

RESUMO

Flavonoids are associated with health benefits, but most of them have poor oral bioavailability due to their extremely low aqueous solubility. Flavonoid O-phosphorylation suggests a potent modification to solve the problems. Here, we isolated, identified and characterized an unprecedented phosphotransferase, flavonoid phosphate synthetase (BsFPS), from B. subtilis. The enzyme catalyzes the ATP-dependent phosphorylation of flavonoid to generate flavonoid monophosphates, AMP and orthophosphate. BsFPS is a promiscuous phosphotransferase that efficiently catalyzes structurally-diverse flavonoids, including isoflavones, flavones, flavonols, flavanones and flavonolignans. Based on MS and NMR analysis, the phosphorylation mainly occurs on the hydroxyl group at C-7 of A-ring or C-4' of B-ring in flavonoid skeleton. Notably, BsFPS is regioselective for the ortho-3',4'-dihydroxy moiety of catechol-containing structures, such as luteolin and quercetin, to produce phosphate conjugates at C-4' or C-3' of B-ring. Our findings highlight the potential for developing biosynthetic platform to obtain new phosphorylated flavonoids for pharmaceutical and nutraceutical applications.


Assuntos
Flavanonas , Flavonas , Flavonolignanos , Isoflavonas , Monofosfato de Adenosina , Trifosfato de Adenosina , Bacillus subtilis , Catecóis , Flavonoides/química , Ligases , Luteolina , Fosfatos , Fosfotransferases , Quercetina
2.
Methods Mol Biol ; 2555: 205-212, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36306089

RESUMO

Phages are viruses of bacteria and have been known for over a century. They do not have a metabolism or protein synthesis machinery and rely on host cells for replication. The model organism Bacillus subtilis has served as a host strain for decades and enabled the isolation of many unique viral strains. However, many viral species representatives remained orphans as no, or only a few, related phages were ever re-isolated.The presented protocol describes how a CRISPR-Cas9 system with an artificial CRISPR-array can be set up and used to discriminate abundant and well-known B. subtilis phage from a host-based metagenome enrichment. The obtained viral suspension can be used for metagenome sequencing and isolating new viral strains.


Assuntos
Bacillus subtilis , Bacteriófagos , Bacillus subtilis/genética , Sistemas CRISPR-Cas/genética , Metagenoma
3.
Dev Comp Immunol ; 138: 104553, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36122732

RESUMO

The intensification and diversification of production systems have increased the incidence of diseases, which are usually treated with antibiotics. However, its use should be restricted due to the increasing prevalence of antibiotic-resistant bacteria. Probiotics represent therefore an alternative environmentally friendly strategy for improving growth and disease resistance in aquaculture. Considering that host-derived probiotics may offer greater advantages than those from other environments in terms of safety and efficacy, two potential host-associated probiotic strains (Bacillus mojavensis B191 and Bacillus subtilis MRS11) were used in the present study, which were previously isolated from intestinal mucus of Nile tilapia (Oreochromis niloticus). This study was conducted to assess the effects of dietary administration of two Bacillus strains on growth performance, intestinal morphology, immunity, and disease resistance of Nile tilapia. A total of 375 fish were randomly divided into five groups in triplicate. Nile tilapia were fed a basal diet (control group) or a basal diet supplemented with Bacillus mojavensis B191 (BM) or Bacillus subtilis MRS11 (BS) spores at different concentrations of 1 × 106 (BM6 and BS6, respectively) and 1 × 108 (BM8 and BS8, respectively) CFU/g of feed for 60 days. Moreover, the survival rate of tilapia upon challenge with Streptococcus iniae was determined following the feeding trial. After the feeding trial, the growth performances were significantly improved in all probiotic-fed groups, with the BS8 group being the highest. Light and electron microscopy observations revealed elevated goblet cells, intestinal villus length (except BM8), microvilli length, microvilli density, and perimeter ratio increase in the intestine of all probiotic-fed groups compared with the control group. Regarding the expression analysis, HSP70 gene was only up-regulated in the BM8 group and a general trend of up-regulation of some immune-related cytokines (TGF-ß, IL-10, TNF-α and IL-1ß) was observed in all probiotic-fed groups. Likewise, the best protection against Streptococcus iniae was observed in the BS8 group, followed by BS6, BM6 and BM8 groups. Altogether, dietary probiotic supplementation with BS8 and BM6 may improve growth performance, intestinal morphology, immunity, and disease resistance in Nile tilapia.


Assuntos
Bacillus , Ciclídeos , Doenças dos Peixes , Probióticos , Ração Animal/análise , Animais , Antibacterianos/farmacologia , Bacillus subtilis , Dieta , Suplementos Nutricionais , Resistência à Doença , Interleucina-10 , Intestinos , Streptococcus iniae/fisiologia , Fator de Crescimento Transformador beta , Fator de Necrose Tumoral alfa
4.
Food Microbiol ; 109: 104137, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36309456

RESUMO

The sterilizing effect of a combination of heat (80, 90, and 100 °C) and ε-polylysine (ε-PL, 0.25 and 1 g/L) treatments on Bacillus subtilis spores was investigated and compared with that of conventional heat sterilization. The inactivation rate of spores and changes in their protective structure were evaluated using different methods and techniques. Changes in cell membrane's fatty acids, cell walls, proteins and nucleic acids were also analyzed. The results showed that the combined heat and ε-PL treatments significantly (p < 0.05) inactivated the Bacillus subtilis spores compared with the single heat treatment. Besides, the inactivation of spores was enhanced as the temperature and ε-PL concentration of combined treatments increased. The inactivation rate was found to be 2.18 log after heating at 90 °C for 60 min combined with the addition of 1 g/L ε-PL. Additionally, the electrical conductivity of spores' suspension and the positive region of flow cytometry significantly (p < 0.05) increased depending on temperature and ε-PL concentration of a combination treatment, indicating significant damage in the cell membranes and increased permeability. Significant changes in the spore morphology were also observed by the microscopy analysis after a combination treatment. Furthermore, the Fourier transform infrared spectra indicated a phase change in the inner membrane and alteration in the structure of peptidoglycan layer, as well as protein and nucleic acids denaturation after combined treatments. Therefore, the combined heat and ε-PL treatments can be suggested as sterilizing alternative to conventional heat sterilization in the food industry.


Assuntos
Bacillus subtilis , Ácidos Nucleicos , Esporos Bacterianos , Temperatura Alta , Polilisina/farmacologia , Ácidos Nucleicos/metabolismo , Ácidos Nucleicos/farmacologia
5.
Food Chem ; 399: 133993, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36029678

RESUMO

At present, uncovering how to preventandcontrol hyperuricemia has become an important public health issue. Fermented traditionalChinesemedicine has exhibited promising applications in the clinical management of hyperuricemia. In this study, we generated a hyperuricemic mouse model to explore the potent therapeutic ability of Bacillus subtilis-fermented Astragalus membranaceus (BFA) on this condition by multi-omics analysis. We found that the serum uric acid level was decreased in hyperuricemic mice after BFA treatment. BFA effectively attenuated renal inflammation and regulated the expression of urate transporters. Additionally, we found that BFA could increase the abundances of butyrate-producing bacteria, including Butyricimonas synergistica, Odoribacter splanchnicus, and Collinsella tanakaei, and probiotics, including Lactobacillus intestinalis and Bacillus mycoides, in hyperuricemic mice. Therefore, we believe that BFA has the potential to become a novel safe and valid functional food for addressing hyperuricemia.


Assuntos
Microbioma Gastrointestinal , Hiperuricemia , Animais , Astragalus propinquus/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Hiperuricemia/tratamento farmacológico , Hiperuricemia/genética , Rim , Camundongos , Ácido Úrico/metabolismo
6.
Braz. j. biol ; 83: e250550, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345536

RESUMO

Abstract Vanillin is the major component which is responsible for flavor and aroma of vanilla extract and is produced by 3 ways: natural extraction from vanilla plant, chemical synthesis and from microbial transformation. Current research was aimed to study bacterial production of vanillin from native natural sources including sewage and soil from industrial areas. The main objective was vanillin bio-production by isolating bacteria from these native sources. Also to adapt methodologies to improve vanillin production by optimized fermentation media and growth conditions. 47 soil and 13 sewage samples were collected from different industrial regions of Lahore, Gujranwala, Faisalabad and Kasur. 67.7% bacterial isolates produced vanillin and 32.3% were non-producers. From these 279 producers, 4 bacterial isolates selected as significant producers were; A3, A4, A7 and A10. These isolates were identified by ribotyping as A3 Pseudomonas fluorescence (KF408302), A4 Enterococcus faecium (KT356807), A7 Alcaligenes faecalis (MW422815) and A10 Bacillus subtilis (KT962919). Vanillin producers were further tested for improved production of vanillin and were grown in different fermentation media under optimized growth conditions for enhanced production of vanillin. The fermentation media (FM) were; clove oil based, rice bran waste (residues oil) based, wheat bran based and modified isoeugenol based. In FM5, FM21, FM22, FM23, FM24, FM30, FM31, FM32, FM34, FM35, FM36, and FM37, the selected 4 bacterial strains produced significant amounts of vanillin. A10 B. subtilis produced maximum amount of vanillin. This strain produced 17.3 g/L vanillin in FM36. Cost of this fermentation medium 36 was 131.5 rupees/L. This fermentation medium was modified isoeugenol based medium with 1% of isoeugenol and 2.5 g/L soybean meal. ech gene was amplified in A3 P. fluorescence using ech specific primers. As vanillin use as flavor has increased tremendously, the bioproduction of vanillin must be focused.


Resumo A vanilina é o principal componente responsável pelo sabor e aroma do extrato de baunilha e é produzida de três formas: extração natural da planta da baunilha, síntese química e transformação microbiana. A pesquisa atual teve como objetivo estudar a produção bacteriana de vanilina a partir de fontes naturais nativas, incluindo esgoto e solo de áreas industriais. O objetivo principal era a bioprodução de vanilina por meio do isolamento de bactérias dessas fontes nativas. Também para adaptar metodologias para melhorar a produção de vanilina por meio de fermentação otimizada e condições de crescimento. Foram coletadas 47 amostras de solo e 13 de esgoto de diferentes regiões industriais de Lahore, Gujranwala, Faisalabad e Kasur; 67,7% dos isolados bacterianos produziram vanilina e 32,3% eram não produtores. Desses 279 produtores, 4 isolados bacterianos selecionados como produtores significativos foram: A3, A4, A7 e A10. Esses isolados foram identificados por ribotipagem como fluorescência A3 Pseudomonas (KF408302), A4 Enterococcus faecium (KT356807), A7 Alcaligenes faecalis (MW422815) e A10 Bacillus subtilis (KT962919). Os produtores de vanilina foram posteriormente testados para produção aprimorada de vanilina e foram cultivados em diferentes meios de fermentação sob condições de crescimento otimizadas para produção aprimorada de vanilina. Os meios de fermentação (FM) foram: à base de óleo de cravo, à base de resíduos de farelo de arroz (resíduos de óleo), à base de farelo de trigo e à base de isoeugenol modificado. Em FM5, FM21, FM22, FM23, FM24, FM30, FM31, FM32, FM34, FM35, FM36 e FM37, as 4 cepas bacterianas selecionadas produziram quantidades significativas de vanilina. A10 B. subtilis produziu quantidade máxima de vanilina. Essa cepa produziu 17,3 g / L de vanilina em FM36. O custo desse meio de fermentação 36 foi de 131,5 rúpias / L. Esse meio de fermentação foi um meio à base de isoeugenol modificado com 1% de isoeugenol e 2,5 g / L de farelo de soja. O gene ech foi amplificado em A3 P. fluorescence usando primers específicos para ech. Como o uso da vanilina como sabor aumentou tremendamente, a bioprodução da vanilina deve ser focada.


Assuntos
Benzaldeídos/metabolismo , Aromatizantes/metabolismo , Bacillus subtilis/metabolismo , Microbiologia Industrial , Pseudomonas fluorescens/metabolismo , Enterococcus faecium/metabolismo , Meios de Cultura , Alcaligenes faecalis/metabolismo , Fermentação
7.
Braz. j. biol ; 83: e244261, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285633

RESUMO

Abstract Endophytic bacteria serve key roles in the maintenance of plant health and growth. Few studies to date, however, have explored the antagonistic and plant growth-promoting (PGP) properties of Prunus cerasifera endophytes. To that end, we isolated endophytic bacteria from P. cerasifera tissue samples and used a dual culture plate assay to screen these microbes for antagonistic activity against Verticillium dahliae, Botryosphaeria dothidea, Fusarium oxysporum, F. graminearum, and F. moniliforme. Of the 36 strains of isolated bacteria, four (strains P1, P10, P16, and P20) exhibited antagonistic effects against all five model pathogens, and the P10 strain exhibited the strongest antagonistic to five pathogens. This P10 strain was then characterized in-depth via phenotypic assessments, physiological analyses, and 16s rDNA sequencing, revealing it to be a strain of Bacillus subtilis. Application of a P10 cell suspension (1×108 CFU/mL) significantly enhanced the seed germination and seedling growth of tomato in a greenhouse setting. This P10 strain further significantly suppressed tomato Verticillium wilt with much lower disease incidence and disease index scores being observed following P10 treatment relative to untreated plants in pot-based experiments. Tomato plants that had been treated with strain P10 also enhanced defense-related enzymes, peroxidase, superoxide dismutase, and catalase activity upon V. dahliae challenge relative to plants that had not been treated with this endophytic bacterium. The results revealed that the P10 bacterial strain has potential value as a biocontrol agent for use in the prevention of tomato Verticillium wilt.


Resumo As bactérias endofíticas desempenham papel fundamental na manutenção da saúde e do crescimento das plantas. Poucos estudos até o momento, no entanto, exploraram as propriedades antagônicas e promotoras de crescimento de plantas (PGP) de endófitos de Prunus cerasifera. Para esse fim, isolamos bactérias endofíticas de amostras de tecido de P. cerasifera e usamos um ensaio de placa de cultura dupla para rastrear esses micróbios quanto à atividade antagonista contra Verticillium dahliae, Botryosphaeria dothidea, Fusarium oxysporum, F. graminearum e F. moniliforme. Das 36 cepas de bactérias isoladas, quatro (cepas P1, P10, P16 e P20) exibiram efeitos antagônicos contra todos os cinco patógenos modelo, e a cepa P10 exibiu o antagonista mais forte para cinco patógenos. Essa cepa P10 foi então caracterizada em profundidade por meio de avaliações fenotípicas, análises fisiológicas e sequenciamento de rDNA 16s, revelando ser uma cepa de Bacillus subtilis. A aplicação de uma suspensão de células P10 (1 × 108 UFC / mL) aumentou significativamente a germinação das sementes e o crescimento das mudas de tomate em casa de vegetação. Essa cepa P10 suprimiu ainda mais a murcha de Verticillium do tomate com incidência de doença muito menor e pontuações de índice de doença sendo observadas após o tratamento com P10 em relação a plantas não tratadas em experimentos baseados em vasos. As plantas de tomate que foram tratadas com a cepa P10 também aumentaram as enzimas relacionadas à defesa, peroxidase, superóxido dismutase e atividade da catalase após o desafio de V. dahliae em relação às plantas que não foram tratadas com essa bactéria endofítica. Os resultados revelaram que a cepa bacteriana P10 tem valor potencial como agente de biocontrole para uso na prevenção da murcha de Verticillium em tomate.


Assuntos
Lycopersicon esculentum , Verticillium , Prunus domestica , Doenças das Plantas/prevenção & controle , Ascomicetos , Bacillus subtilis , Fusarium
8.
Nutrients ; 14(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36364738

RESUMO

Weaning stress induces intestinal barrier dysfunction and immune dysregulation in mammals. Various interventions based on the modulation of intestinal microbiota have been proposed. Our study aims to explore the effects of co-cultures from Lactobacillus acidophilus and Bacillus subtilis (FAM®) on intestinal mucosal barrier from the perspective of metabolic function of gut microbiota. A total of 180 piglets were allocated to three groups, i.e., a control group (C, basal diet), a FAM group (F, basal diet supplemented with 0.1% FAM), and an antibiotic group (A, basal diet supplemented with antibiotic mixtures). Here, we showed FAM supplementation significantly increased body weight and reduced diarrhea incidence, accompanied by attenuated mucosal damage, increased levels of tight junction proteins, serum diamine oxidase (DAO) and antimicrobial peptides. In addition, 16S rRNA sequencing and metabolomic analysis revealed an increase in relative abundance of Clostridiales, Ruminococcaceae, Firmicutes and Muribaculaceae and a significant increase in the total short-chain fatty acids (SCFAs) and butyric acid in FAM-treated piglets. FAM also increased CD4+ T cells and SIgA+ cells in intestinal mucosa and SIgA production in colon contents. Furthermore, FAM upregulated the expression of IL-22, short-chain fatty acid receptors GPR43 and GPR41, aryl hydrocarbon receptor (AhR), and hypoxia-inducible factor 1α (HIF-1α). FAM shows great application prospect in gut health and provides a reference for infant weaning.


Assuntos
Microbioma Gastrointestinal , Animais , Suínos , Lactobacillus acidophilus , Bacillus subtilis , Técnicas de Cocultura , RNA Ribossômico 16S , Ácidos Graxos Voláteis/metabolismo , Ácido Butírico/metabolismo , Antibacterianos/farmacologia , Imunoglobulina A Secretora , Mamíferos/metabolismo
9.
Nat Commun ; 13(1): 7082, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36400765

RESUMO

Many bacteria in nature exist in multicellular communities termed biofilms, where cells are embedded in an extracellular matrix that provides rigidity to the biofilm and protects cells from chemical and mechanical stresses. In the Gram-positive model bacterium Bacillus subtilis, TasA is the major protein component of the biofilm matrix, where it has been reported to form functional amyloid fibres contributing to biofilm structure and stability. Here, we present electron cryomicroscopy structures of TasA fibres, which show that, rather than forming amyloid fibrils, TasA monomers assemble into fibres through donor-strand exchange, with each subunit donating a ß-strand to complete the fold of the next subunit along the fibre. Combining electron cryotomography, atomic force microscopy, and mutational studies, we show how TasA fibres congregate in three dimensions to form abundant fibre bundles that are essential for B. subtilis biofilm formation. Our study explains the previously observed biochemical properties of TasA and shows how a bacterial extracellular globular protein can assemble from monomers into ß-sheet-rich fibres, and how such fibres assemble into bundles in biofilms.


Assuntos
Bacillus subtilis , Aranhas , Animais , Bacillus subtilis/metabolismo , Biofilmes , Proteínas de Bactérias/metabolismo , Amiloide/metabolismo , Aranhas/metabolismo
10.
Arch Microbiol ; 204(12): 715, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36400871

RESUMO

Bacillus subtilis (BS) has been used as an excellent probiotic; however, some BS strains seem to be opportunist pathogens or do not present inhibitory effects in the pathogenic bacteria, so the characterization of BS strains for use in animals is mandatory. This study aimed to select nonpathogenic strains of BS, which can inhibit Salmonella spp., avian pathogenic Escherichia coli (APEC), and Campylobacter jejuni (CJ) using a chicken embryo as a model. We tested nine (9) strains of BS isolated from several sources (named A to I) in in vitro by tests of mucin degradation activity, haemolytic activity, apoptosis, and necrosis in fibroblasts from chickens. After the in vitro test, we tested the remaining seven (7) strains (strains A to G) in a chicken embryo (CE) as an in vivo model and target animal. We inoculated 3 log CFU/CE of each strain via allantoic fluid at the 10th day postincubation (DPI). Each treatment group consisted of eight CEs. At the 17th DPI we checked CE mortality, gross lesions, CE weight, and whether BS strains were still viable. To perform the cytokine, total protein, albumin, and reactive C protein analysis, we collected the CE blood from the allantoic vessel and intestine fragments in the duodenum portion for histomorphometric analysis. After the results in CEs, we tested the inhibition capacity of the selected BS strains for diverse strains of Salmonella  Heidelberg (SH), S. Typhimurium (ST), S. Enteritidis (SE), S. Minnesota (SM), S. Infantis (SI), Salmonella var. monophasic (SVM), APEC and C. jejuni. After the in vitro trial (mucin degradation activity, haemolytic activity, apoptosis, and necrosis), we removed two (2) strains (H and I) that showed ß-haemolysis, mucin degradation, and/or high apoptosis and necrosis effects. Although all strains of BS were viable in CEs at the 17th DPI, we removed four (4) strains (A, B, D, F) once they led to the highest mortality in CEs or a high albumin/protein ratio. C. jejuni inoculated with strain G had greater weight than the commercial strain, which could be further used for egg inoculation with benefits to the CE. From the tests in CEs, we selected the strains C, E, and G for their ability to inhibit pathogenic strains of relevant foodborne pathogens. We found that the inhibition effect was strain dependent. In general, strains E and/or G presented better or similar results than commercial control strains in the inhibition of SH, ST, SI, APEC, and two (2) strains of CJ. In this study, we selected BS strains C, E and G due to their in vitro and in vivo safety and beneficial effects. In addition, we emphasize the value of CE as an in vivo experimental model for assessing BS's safety and possible benefits for poultry and other animals.


Assuntos
Campylobacter jejuni , Infecções por Escherichia coli , Probióticos , Embrião de Galinha , Animais , Galinhas/microbiologia , Bacillus subtilis , Escherichia coli , Mucinas , Necrose
11.
Curr Microbiol ; 79(12): 398, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352269

RESUMO

A bacterium strain isolated from freshwater sediment of San Pablo river of Santiago de Cuba, Cuba was identified as a Bacillus sp. by Matrix-Assisted Laser Desorption/Ionization Time Of Flight Mass Spectrometry. A 16S rRNA gene analysis showed that the isolate A3 belongs to the operational group Bacillus amyloliquefaciens, while the phylogenetic analysis of the gyrA gene sequence grouped it within B. amyloliquefaciens subsp. plantarum cluster, referred now as Bacillus velezensis. In vitro antibacterial studies demonstrated the capacity of the isolate A3 to produce bioactive metabolites against Bacillus subtilis ATCC 11,778, Bacillus cereus ATCC 6633, and Staphylococcus aureus ATCC 25,923 by cross-streak, overlay, and microdilution methods. The strain also showed a high potential against the multidrug-resistant Staphylococcus aureus ATCC 700,699, ATCC 29,213, and ATCC 6538. At pH 8 and 96 h in the medium 2 of A3 culture conditions, the produced metabolites with antibacterial potential were enhanced. Some alterations in the morphology of the phytopathogens Aspergillus niger ATCC 9642, Alternaria alternata CECT 2662, and Fusarium solani CCEBI 3094 were induced by the cell-free supernatant of B. velezensis A3. A preliminary study of the nature of the bioactive compounds produced by the strain A3 showed the presence of both lipids and peptides in the culture. Those results highlight B. velezensis A3 as a promissory bacterium capable to produce bioactive metabolites with antibacterial and antifungal properties against pathogens.


Assuntos
Bacillus , Staphylococcus aureus Resistente à Meticilina , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Filogenia , Bacillus/genética , Bacillus/metabolismo , Fungos/genética , Bacillus subtilis/metabolismo , Antibacterianos/química , Água Doce
12.
World J Microbiol Biotechnol ; 39(1): 12, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36372802

RESUMO

Transcriptional factors are well studied in bacteria for their global interactions and the effects they produce at the phenotypic level. Particularly, Bacillus subtilis has been widely employed as a model Gram-positive microorganism used to characterize these network interactions. Bacillus species are currently used as efficient commercial microbial platforms to produce diverse metabolites such as extracellular enzymes, antibiotics, surfactants, industrial chemicals, heterologous proteins, among others. However, the pleiotropic effects caused by the genetic modification of specific genes that codify for global regulators (transcription factors) have not been implicated commonly from a bioprocess point of view. Recently, these strategies have attracted the attention in Bacillus species because they can have an application to increase production efficiency of certain commercial interest metabolites. In this review, we update the recent advances that involve this trend in the use of genetic engineering (mutations, deletion, or overexpression) performed to global regulators such as Spo0A, CcpA, CodY and AbrB, which can provide an advantage for the development or improvement of bioprocesses that involve Bacillus species as production platforms. Genetic networks, regulation pathways and their relationship to the development of growth stages are also discussed to correlate the interactions that occur between these regulators, which are important to consider for application in the improvement of commercial-interest metabolites. Reported yields from these products currently produced mostly under laboratory conditions and, in a lesser extent at bioreactor level, are also discussed to give valuable perspectives about their potential use and developmental level directed to process optimization at large-scale.


Assuntos
Bacillus , Fatores de Transcrição , Fatores de Transcrição/genética , Bacillus/genética , Bacillus/metabolismo , Bacillus subtilis/metabolismo , Engenharia Genética , Redes Reguladoras de Genes , Proteínas de Bactérias/metabolismo , Transcrição Genética
13.
Molecules ; 27(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36364415

RESUMO

Bacterial resistance to antibiotics is on the rise and hinders the fight against bacterial infections, which are expected to cause millions of deaths by 2050. New antibiotics are difficult to find, so alternatives are needed. One could be metal-based drugs, such as silver nanoparticles (AgNPs). In general, chemical methods for AgNPs' production are potentially toxic, and the physical ones expensive, while green approaches are not. In this paper, we present the green synthesis of AgNPs using two Pseudomonas alloputida B003 UAM culture broths, sampled from their exponential and stationary growth phases. AgNPs were physicochemically characterized by transmission electron microscopy (TEM), total reflection X-ray fluorescence (TXRF), infrared spectroscopy (FTIR), dynamic light scattering (DLS), and X-ray diffraction (XRD), showing differential characteristics depending on the synthesis method used. Antibacterial activity was tested in three assays, and we compared the growth and biofilm-formation inhibition of six test bacteria: Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis. We also monitored nanoparticles' synergic behavior through the growth inhibition of E. coli and S. aureus by three classical antibiotics: ampicillin, nalidixic acid, and streptomycin. The results indicate that very good AgNP activity was obtained with particularly low MICs for the three tested strains of P. aeruginosa. A good synergistic effect on streptomycin activity was observed for all the nanoparticles. For ampicillin, a synergic effect was detected only against S. aureus. ROS production was found to be related to the AgNPs' antibacterial activity.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Antibacterianos/química , Prata/farmacologia , Prata/química , Staphylococcus aureus , Nanopartículas Metálicas/química , Escherichia coli , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa , Bacillus subtilis , Biofilmes , Ampicilina/farmacologia , Estreptomicina/farmacologia , Extratos Vegetais/química
14.
Molecules ; 27(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36364482

RESUMO

Agaricus bisporus, the most widely cultivated mushroom, is safe to eat and enriched with protein and secondary metabolites. We prepared silver nanoparticles (AgNPs) from two varieties of A. bisporus and tested their antibacterial activity The synthesized AgNPs were initially confirmed by UV-Vis spectroscopy peaks at 420 and 430 nm for white and brown mushrooms AgNPs, respectively. AgNPs were further characterized by zeta sizer, transmission electronic microscopy (TEM), Fourier transform infrared (FTIR), and energy-dispersive X-ray spectroscopy (EDX) prior to antibacterial activity by the well diffusion method against six bacterial strains which include Staphylococcus aureus, Staphylococcus epidermis, Bacillus subtilis, Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa. TEM results revealed a spherical shape with an average diameter of about 11 nm in the white mushroom extract and 5 nm in the brown mushroom extract. The presence of elemental silver in the prepared AgNPs was confirmed by EDS. The IR spectrum of the extract confirmed the presence of phenols, flavonoids, carboxylic, or amide groups which aided in the reduction and capping of synthesized AgNPs. The AgNPs from both extracts showed almost the same results; however, nanoparticles prepared from brown mushrooms were smaller in size with strong antibacterial activity.


Assuntos
Nanopartículas Metálicas , Prata , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Bacillus subtilis , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana
15.
Toxins (Basel) ; 14(11)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36422971

RESUMO

The use of chemical pesticides to control the occurrence of mycotoxigenic fungi in crops has led to environmental and human health issues, driving the agriculture sector to a more sustainable system. Biocontrol agents such as Bacillus strains and their antimicrobial metabolites have been proposed as alternatives to chemical pesticides. In the present work, a broth obtained from a commercial product containing Bacillus subtilis QST 713 was tested for its ability to inhibit the growth of mycotoxigenic fungi as well as reduce their mycotoxin production. Mass spectrometry analysis of Bacillus subtilis broth allowed to detect the presence of 14 different lipopeptides, belonging to the iturin, fengycin, and surfactin families, already known for their antifungal properties. Bacillus subtilis broth demonstrated to be a useful tool to inhibit the growth of some of the most important mycotoxigenic fungi such as Aspergillus flavus, Fusarium verticillioides, Fusarium graminearum, Aspergillus carbonarius, and Alternaria alternata. In addition, cell-free Bacillus subtilis broth provided the most promising results against the growth of Fusarium graminearum and Alternaria alternata, where the radial growth was reduced up to 86% with respect to the untreated test. With regard to the mycotoxin reduction, raw Bacillus subtilis broth completely inhibited the production of aflatoxin B1, deoxynivalenol, zearalenone, and tenuazonic acid. Cell-free broth provided promising inhibitory properties toward all of the target mycotoxins, even if the results were less promising than the corresponding raw broth. In conclusion, this work showed that a commercial Bacillus subtilis, characterized by the presence of different lipopeptides, was able to reduce the growth of the main mycotoxigenic fungi and inhibit the production of related mycotoxins.


Assuntos
Micotoxinas , Praguicidas , Humanos , Micotoxinas/toxicidade , Bacillus subtilis , Alternaria , Lipopeptídeos/farmacologia
16.
PLoS One ; 17(11): e0277412, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36417387

RESUMO

Since the prohibition of antibiotics as animal growth promoters, demand for effective probiotic strains has steadily increased. The goal is to maintain productivity and mitigate environmental concerns in the livestock industry. There are many probiotic animal-diet supplements available, over 2,000 products in the Republic of Korea alone, with little explanation about the desirable properties of each probiotic strain. The purpose of this study was to describe the underlying logic and methods used to select two novel strains of probiotic candidates. To economically screen these candidates, the abundance of surfactin secreted was used as an in vitro marker. We used a modified oil-misting method to screen ~2,000 spore-forming bacteria for novel strains of Bacillus subtilis. Of these, 18 strains were initially selected based on the semiquantitative criterion that they secreted more surfactin than B. subtilis ATCC21322 on Luria-Berani (LB) agar plates. The whole genome sequence was determined for two of the 18 strains to verify their identity. A phylogeny of 1,162 orthologous genes, genome contents, and genome organization confirmed them as novel strains. The surfactin profiles produced by these two strains consisted of at least four isoforms similar to standard surfactin and enhanced cellulase activities up to 50%. Four fractionated individual isoforms of surfactin suppressed inflammation induced by lipopolysaccharides. The half-maximal inhibitory concentration (IC50) was about 20 µM for each isoform. Both selected strains were susceptible to seven important antibiotics. Our results implied that an abundant secretion of surfactin was a useful biomarker in vitro and could be utilized for mining probiotic candidates through high-throughput screening of environmental samples.


Assuntos
Bacillus subtilis , Probióticos , Animais , Bacillus subtilis/genética , Transporte Biológico , Pesquisa , Antibacterianos
17.
Mar Drugs ; 20(11)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36422004

RESUMO

A chemical investigation of a methanol extract of Spongia sp., a marine sponge collected from the Philippines, identified 12 unreported scalarane-type alkaloids-scalimides A-L (1-12)-together with two previously described scalarin derivatives. The elucidation of the structure of the scalaranes based on the interpretation of their NMR and HRMS data revealed that 1-12 featured a ß-alanine-substituted E-ring but differed from each other through variations in their oxidation states and substitutions occurring at C16, C24, and C25. Evaluation of the antimicrobial activity of 1-12 against several Gram-positive and Gram-negative bacteria showed that 10 and 11 were active against Micrococcus luteus and Bacillus subtilis, respectively, with MIC values ranging from 4 to 16 µg/mL.


Assuntos
Antibacterianos , Poríferos , Animais , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Bacillus subtilis , Metanol
18.
Science ; 378(6615): 25-26, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36201570

RESUMO

Inactive spores integrate stimuli over time through stored electrochemical potential.


Assuntos
Bacillus subtilis , Esporos Bacterianos , Bacillus subtilis/fisiologia , Eletroquímica , Fenômenos Eletrofisiológicos , Esporos Bacterianos/fisiologia
19.
Science ; 378(6615): 43-49, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36201591

RESUMO

The dormant state of bacterial spores is generally thought to be devoid of biological activity. We show that despite continued dormancy, spores can integrate environmental signals over time through a preexisting electrochemical potential. Specifically, we studied thousands of individual Bacillus subtilis spores that remain dormant when exposed to transient nutrient pulses. Guided by a mathematical model of bacterial electrophysiology, we modulated the decision to exit dormancy by genetically and chemically targeting potassium ion flux. We confirmed that short nutrient pulses result in step-like changes in the electrochemical potential of persistent spores. During dormancy, spores thus gradually release their stored electrochemical potential to integrate extracellular information over time. These findings reveal a decision-making mechanism that operates in physiologically inactive cells.


Assuntos
Bacillus subtilis , Antiportadores de Potássio-Hidrogênio , Esporos Bacterianos , Bacillus subtilis/fisiologia , Fenômenos Eletrofisiológicos , Modelos Biológicos , Potássio/fisiologia , Antiportadores de Potássio-Hidrogênio/fisiologia , Esporos Bacterianos/fisiologia
20.
Front Immunol ; 13: 1007202, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189301

RESUMO

The oral mucosal vaccine has great potential in preventing a series of diseases caused by porcine circovirus type 2 (PCV2) infection. This study constructed a recombinant Bacillus subtilis RB with PCV2 Capsid protein (Cap) on its spore surface and cotB as a fusion partner. The immune properties of the recombinant strain were evaluated in a mouse model. IgA in intestinal contents and IgG in serum were detected by enzyme-linked immunosorbent assay (ELISA). The results demonstrated that recombinant spores could activate strong specific mucosal and humoral immune responses. In addition, spores showed good mucosal immune adjuvant function, promoting the proliferation of CD3+, CD4+ and CD8+ T cells and other immune cells. We also found that the relative expression of inflammatory cytokines such as IL-1ß, IL-6, IL-10, TNF-α and IFN in the small intestinal mucosa was significantly up-regulated under the stimulation of recombinant bacteriophage. These effects are important for the balance of Th1/Th2-like responses. In summary, our results suggest that recombinant B. subtilis RB as a feed additive provides a new strategy for the development of novel and safe PCV2 mucosal subunit vaccines.


Assuntos
Circovirus , Vacinas Virais , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais , Bacillus subtilis/genética , Proteínas do Capsídeo/genética , Circovirus/genética , Imunoglobulina A , Imunoglobulina G , Interleucina-10 , Interleucina-6 , Camundongos , Esporos Bacterianos , Suínos , Fator de Necrose Tumoral alfa , Vacinas de Subunidades
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