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1.
J Biosci Bioeng ; 130(1): 48-53, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32224010

RESUMO

Macrolactins (MLNs) have attracted considerable attention due to their antibacterial and antiviral properties. Here, the MLN production of Bacillus sp. strain IMDGX0108 was improved using a breeding strategy of atmospheric room temperature plasma (ARTP) technique. Combining with a selection procedure based on the colony morphology and specific growth rate index (SGRI), two genetically stable mutants A29 and A72 were identified. The MLN production of A29 and A72 was 35.2% and 52.8% greater than that of the parent strain, respectively. The best-performing mutant A72 was subjected to RNA-sequence analysis. Five pathways were significantly enriched, and fatty acid bioprocesses might play an important role in improving the production of MLNs. The combined strategy developed herein (i.e., ARTP mutation plus an efficient screening procedure) might be an appropriate method by which to obtain strains overproducing MLNs.


Assuntos
Bacillus/efeitos dos fármacos , Bacillus/crescimento & desenvolvimento , Alcaloides Indólicos/metabolismo , Gases em Plasma/farmacologia , Bacillus/química , Bacillus/genética , Ácidos Graxos/metabolismo , Cinética , Mutação
2.
PLoS One ; 15(3): e0229886, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130283

RESUMO

Halophiles are the organisms that thrive in extreme high salt environments. Despite the extensive studies on their biotechnological potentials, the ability of halophilic prokaryotes for the synthesis of nanoparticles has remained understudied. In this study, the archaeal and bacterial halophiles from a solar saltern were investigated for the intracellular/extracellular synthesis of silver and selenium nanoparticles. Silver nanoparticles were produced by the archaeal Haloferax sp. (AgNP-A, intracellular) and the bacterial Halomonas sp. (AgNP-B, extracellular), while the intracellular selenium nanoparticles were produced by the archaeal Halogeometricum sp. (SeNP-A) and the bacterial Bacillus sp. (SeNP-B). The nanoparticles were characterized by various techniques including UV-Vis spectroscopy, XRD, DLS, ICP-OES, Zeta potentials, FTIR, EDX, SEM, and TEM. The average particle size of AgNP-A and AgNP-B was 26.34 nm and 22 nm based on TEM analysis. Also, the characteristic Bragg peaks of face-centered cubic with crystallite domain sizes of 13.01 nm and 6.13 nm were observed in XRD analysis, respectively. Crystallographic characterization of SeNP-A and SeNP-B strains showed a hexagonal crystallite structure with domain sizes of 30.63 nm and 29.48 nm and average sizes of 111.6 nm and 141.6 nm according to TEM analysis, respectively. The polydispersity index of AgNP-A, AgNP-B, SeNP-A, and SeNP-B was determined as 0.26, 0.28, 0.27, and 0.36 and revealed high uniformity of the nanoparticles. All of the synthesized nanoparticles were stable and their zeta potentials were calculated as (mV): -33.12, -35.9, -31.2, and -29.34 for AgNP-A, AgNP-B, SeNP-A, and SeNP-B, respectively. The nanoparticles showed the antibacterial activity against various bacterial pathogens. The results of this study suggested that the (extremely) halophilic prokaryotes have great potentials for the green synthesis of nanoparticles.


Assuntos
Antibacterianos/química , Extremófilos/química , Nanopartículas Metálicas/química , Células Procarióticas/química , Antibacterianos/farmacologia , Bacillus/química , Bactérias/efeitos dos fármacos , Bactérias/patogenicidade , Halobacteriaceae/química , Humanos , Nanopartículas Metálicas/administração & dosagem , Tamanho da Partícula , Selênio/química , Prata/química
3.
PLoS One ; 15(2): e0228052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053625

RESUMO

The rod shape of bacilli is maintained by bacterial cytoskeletal protein MreB, an actin homolog that acts in concert with the inner membrane protein RodZ. We previously reported RodZ binds RNA to control the posttranscriptional regulation of invE (virB), which controls the type III secretion system essential for the virulence of Shigella. Here, we show that purified RodZ forms "superstructures" of high molecular mass that dissociate into a midsized "basal complex" in the presence of nonionic detergent, or to a monomer in the presence of dithiothreitol. We used mass spectrometry to show that the basal complex was a hexamer. Electrophoresis mobility shift assays combined with gel filtration detected the RNA-binding activity in fractions containing molecules larger than the basal hexamer. The superstructure was consistently detected with MreB in crude cell lysates of S. sonnei that were fractionated using gel filtration. Immunofluorescence microscopy using two different super-resolution settings showed that wild-type RodZ was distributed in cells as separate dots. Consistent with the superstructure comprising homohexamers, majority of the dots distributed among areas of discrete values. In addition, simultaneous immunodetection of MreB provided the first evidence of colocalization with RodZ as larger patch like signals. These findings indicate that native RodZ forms clusters of various sizes, which may correspond to a superstructure comprising multiple hexamers required for the RNA-binding activity.


Assuntos
Bacillus/química , Proteínas de Bactérias/química , Multimerização Proteica , Shigella sonnei/química , Substituição de Aminoácidos , Proteínas de Bactérias/ultraestrutura , Cisteína/genética , Análise Mutacional de DNA , Imageamento Tridimensional , Peso Molecular , Mutação/genética , Domínios Proteicos , Mapeamento de Interação de Proteínas , Shigella sonnei/citologia
4.
Molecules ; 25(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906348

RESUMO

The synthesis of bioplastic from marine microbes has a great attendance in the realm of biotechnological applications for sustainable eco-management. This study aims to isolate novel strains of poly-ß-hydroxybutyrate (PHB)-producing bacteria from the mangrove rhizosphere, Red Sea, Saudi Arabia, and to characterize the extracted polymer. The efficient marine bacterial isolates were identified by the phylogenetic analysis of the 16S rRNA genes as Tamlana crocina, Bacillus aquimaris, Erythrobacter aquimaris, and Halomonas halophila. The optimization of PHB accumulation by E. aquimaris was achieved at 120 h, pH 8.0, 35 °C, and 2% NaCl, using glucose and peptone as the best carbon and nitrogen sources at a C:N ratio of 9.2:1. The characterization of the extracted biopolymer by Fourier-transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (NMR), and Gas chromatography-mass spectrometry (GC-MS) proves the presence of hydroxyl, methyl, methylene, methine, and ester carbonyl groups, as well as derivative products of butanoic acid, that confirmed the structure of the polymer as PHB. This is the first report on E. aquimaris as a PHB producer, which promoted the hypothesis that marine rhizospheric bacteria were a new area of research for the production of biopolymers of commercial value.


Assuntos
Biopolímeros/biossíntese , Biopolímeros/química , Hidroxibutiratos/química , Hidroxibutiratos/metabolismo , Poliésteres/química , Poliésteres/metabolismo , Sphingomonadaceae/química , Sphingomonadaceae/metabolismo , Avicennia/microbiologia , Bacillus/química , Bacillus/genética , Bacillus/metabolismo , Biopolímeros/análise , Carbono/química , Carbono/metabolismo , Fermentação , Flavobacteriaceae/química , Flavobacteriaceae/genética , Flavobacteriaceae/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Halomonas/química , Halomonas/genética , Halomonas/metabolismo , Hidroxibutiratos/análise , Espectroscopia de Ressonância Magnética , Nitrogênio/química , Nitrogênio/metabolismo , Filogenia , Poliésteres/análise , RNA Ribossômico 16S/genética , Rizosfera , Salinidade , Arábia Saudita , Água do Mar/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Temperatura
5.
J Photochem Photobiol B ; 204: 111786, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31982671

RESUMO

Biological synthesis of nanoparticles is a growing research trend because it has numerous applications in pharmaceutics and biomedicine. The aim of this study was to obtain silver nanoparticles (AgNPs) from Bacillus sp. KFU36, a marine strain, and to assess its anticancer activity. The supernatant of Bacillus sp. KFU36 was supplemented with silver nitrate and the nanoparticles obtained were characterized spectrophotometrically and microscopically. A band of surface plasmon resonance was appeared at 430 nm, as revealed by UV-vis spectrophotometry. X-ray diffraction spectrum and Energy Dispersive Spectroscopy confirmed the crystalline and metallic structure of the AgNPs, respectively. Scanning electron microscopy revealed that the shape of the synthesized AgNPs were spherical and the size extended between 5 and 15 nm. The AgNPs were investigated for their potential anticancer effects on the cell viability, migration and apoptosis using MTT and wound-healing assays, and flow cytometry, respectively. The cytotoxic effects of these nanoparticles were evidenced by the decreasing the cell viability (as 15% at 50 µg/ml), cell density, adhesion capacity and losing the normal shape and size, and inducing the apoptosis on MCF-7 by 61% at 50 µg/ml. These findings confirm that the synthesized AgNPs exhibited superior anticancer activities and therefore could be exploited as a promising, cost-effective, and environmentally benign strategy in treating this disease in future.


Assuntos
Bacillus/química , Nanopartículas Metálicas/química , Prata/química , Apoptose/efeitos dos fármacos , Bacillus/classificação , Bacillus/genética , Neoplasias da Mama , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Química Verde , Humanos , Células MCF-7 , Nanopartículas Metálicas/toxicidade , Filogenia
6.
Environ Sci Pollut Res Int ; 27(9): 9167-9180, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31916147

RESUMO

A new approach for easy synthesis of Bacillus pseudomycoides immobilized polyvinyl alcohol (PVA)/glutaraldehyde (GA) hydrogel for application in a wastewater treatment system is reported. Optimization studies revealed that GA/PVA mass ratio of 0.03 and acidic pH of 2 were required for hydrogel synthesis and eventually for bacterial cell immobilization. The synthesized crosslinked matrix possessed a pore size suitable for microbial cell entrapment while maintaining cell accessibility to external environment for bioremediation. Possible crosslinking and bacterial cell immobilization in the hydrogel were evidenced by FTIR, XRD, and SEM studies, respectively. Further, the extent of crosslinking of GA with PVA was investigated and confirmed by transmittance and permeability experiments. The viability and proliferation of hydrogel embedded cells (after 25 days) was confirmed by confocal fluorescence microscopy which also indicated that acidic pH of polymer solution did not affect the immobilized live cells. B. pseudomycoides immobilized hydrogel were demonstrated to be effective for treatment of municipal wastewater and reduced biochemical oxygen demand (BOD), chemical oxygen demand (COD), and protein content below the recommended levels. Overall, the results from this bench-scale work show that employing bacteria-embedded PVA/GA hydrogel for the treatment of municipal wastewater yield promising results which should be further explored in pilot/field-scale studies.


Assuntos
Bacillus/química , Hidrogéis/química , Álcool de Polivinil , Glutaral , Águas Residuárias
7.
J Appl Microbiol ; 128(1): 242-254, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31559664

RESUMO

AIMS: To study the antimicrobial agents of the Bacillus velezensis strain HC6 and assess the application potential of B. velezensis HC6 in maize. METHODS AND RESULTS: We applied a dual culture technique to test the antimicrobial activity of B. velezensis HC6 against bacteria and fungi of common contaminated crops. Bacillus velezensis HC6 showed antagonistic action on pathogenic fungi, including Aspergillus and Fusarium, as well as pathogenic bacteria (especially Listeria monocytogenes). When applied in maize, B. velezensis HC6 could also inhibit the growth of multiple pathogenic fungi and reduce their production of aflatoxin and ochratoxin. Three kinds of antimicrobial lipopeptides, including iturin, fengycin and surfactin were identified in B. velezensis HC6 culture supernatant by high-performance liquid chromatography and MALDI-TOF mass spectrometry. Iturin and fengycin showed obvious antimicrobial activity to the tested fungal strains. CONCLUSIONS: Bacillus velezensis HC6 produces three kinds of lipopeptides which showed antimicrobial activity against several common pathogenic fungi and bacteria. Bacillus velezensis HC6 is potential to be biocontrol bacteria in maize. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacillus velezensis HC6 shows obvious antimicrobial activity to important crops pathogenic fungi which usually produce mycotoxins that are harmful to animal and human health. We demonstrate that three different types of lipopeptides produced by B. velezensis contributed to the antimicrobial activity. Bacillus velezensis HC6 has the potential to be effective biocontrol agent in crops.


Assuntos
Anti-Infecciosos , Bacillus/fisiologia , Agentes de Controle Biológico , Lipopeptídeos/metabolismo , Zea mays/microbiologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bacillus/química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Lipopeptídeos/química , Lipopeptídeos/farmacologia , Micotoxinas/metabolismo , Doenças das Plantas/microbiologia
8.
Colloids Surf B Biointerfaces ; 185: 110514, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639569

RESUMO

Antiseptics and disinfectants are widely applied for eliminating microorganisms. However, microorganisms dwelling in the biofilm are less susceptible and in some cases resistant to biocide treatment. The present study describes isolation and characterization of lipopeptide biosurfactant exhibiting disinfectant-like activity. Biosurfactant was produced by an endo-rhizospheric bacterium Bacillus tequilensis strain SDS21. Biosurfactant reduced the surface tension of water from 72 to 30 mN/m with CMC of 40 mg/l. The Liquid Chromatography-Mass Spectrometry analysis of biosurfactant suggested it to be a mixture of C14, C15, C16 and C17 surfactin homologues. The lipopeptide biosurfactant exhibited bactericidal activity against planktonic cells and biofilm residing sessile cells. The biosurfactant treatment eradicated more than 99% of bacterial biofilm present on polystyrene, glass and stainless steel surface. The biosurfactant retained its bactericidal and biofilm eradicating activities even after exposure to extreme conditions like high temperate and extreme pH. Unlike some of the commonly used disinfectant, biosurfactant retained its bactericidal and biofilm removing activity even in the hard water containing Mg2+ and Ca2+ ions. Thus, suggesting that biosurfactant produced by strain SDS21 can be used as a disinfectant or in disinfectant-like formulations effective against both planktonic and biofilm residing bacteria.


Assuntos
Bacillus/química , Desinfetantes/farmacologia , Lipopeptídeos/farmacologia , Tensoativos/farmacologia , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Testes de Sensibilidade Microbiana , Filogenia , Temperatura
9.
Food Chem ; 303: 125364, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31445176

RESUMO

Lipid oxidation was considered as a problem in food conservation. The present study aims to investigate the effect of lipopeptides DCS1 on the conservation of food models against lipid oxidation by determining the primary and the secondary oxidation products. Lipopeptides DCS1 are able to preserve the nutritional properties of the emulsion during 23 days of storage, at a concentration of 0.0125% (w/w of emulsion), by slowing down the formation of hydroperoxides and malondialdehyde (MDA) compounds. The direct incorporation of lipopeptides in ground beef patties at a concentration of 0.5% (w/w of meat) was found to be more effective than gelatin film enriched with lipopeptides (2.5%, w/w of gelatin) as a coating, in inhibiting lipid oxidation. Furthermore, lipopeptides DCS1 are not toxic to human kidney cells HEK293 up to a concentration of 250 µg/ml. The results indicate that lipopeptides DCS1 are effective for the preservation of fatty foods against lipid oxidation.


Assuntos
Bacillus/química , Lipopeptídeos/farmacologia , Carne Vermelha , Óleo de Girassol/química , Água/química , Animais , Bovinos , Emulsões , Conservação de Alimentos , Células HEK293 , Humanos , Lipídeos/química , Oxirredução/efeitos dos fármacos
10.
Avian Dis ; 63(4): 659-669, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31865681

RESUMO

The aim of the present study was to evaluate the effect of a commercial Bacillus direct-fed microbial (DFM) on aflatoxin B1 toxic effects, performance, and biochemical and immunologic parameters in broiler chickens. Ninety 1-day-old Cobb 500 male broiler chicks were raised in floor pens for a period of 21 days. Chicks were neck-tagged, individually weighed, and randomly allocated to one of three groups: Negative control (basal feed), aflatoxin B1 (basal feed + 2 ppm AFB1), and DFM (basal feed + 2 ppm AFB1 + Bacillus direct-fed microbial). Each group had three replicates of 10 chickens (n = 30/group). Body weight and body weight gain were calculated weekly, while feed intake and feed conversion ratio were determined when broilers were 21 days old. On day 21, all chickens were bled, gastrointestinal samples were collected, and spleen and bursa of Fabricius were weighed. This study confirmed that 2 ppm of AFB1 causes severe detrimental effects on performance, biochemical parameters, and immunologic parameters, generating hepatic lesions in broiler chickens (P < 0.05). However, it was also observed that DFM supplementation provided beneficial effects that might help to improve gut barrier function, anti-inflammatory and antioxidant activities, as well as humoral and cellular immunomodulation. The results of the present study suggest that this Bacillus-DFM added at a concentration of 106 spores/gram of feed can be used to counteract the negative effects that occur when birds consume diets contaminated with AFB1, showing beneficial effects on performance parameters, relative organ weights, hepatic lesions, immune response, and serum biochemical variables. The addition of this Bacillus-DFM might mitigate and decrease aflatoxicosis problems in the poultry industry, improving food security, alleviating public health problems, and providing economic benefits. Future studies are needed to fully elucidate the specific mechanisms by which this Bacillus-DFM counteracts the toxic effects of aflatoxin B1.


Assuntos
Bacillus/química , Galinhas/imunologia , Probióticos/farmacologia , Aflatoxina B1/toxicidade , Ração Animal/análise , Animais , Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Dieta/veterinária , Masculino , Distribuição Aleatória
11.
Poult Sci ; 98(12): 6483-6491, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31549175

RESUMO

This study evaluated the effect of in ovo Bacillus spp. base probiotic (BBP) administration on hatchability, Gram-negative bacteria (GNB) recovery, performance, and microbiota composition in 2 independent trials using a virulent E. coli seeder challenge model. In each trial, one hundred and eighty 18-day-old embryos were allocated into 1 of 2 groups: Control and treated group (inoculated with 107 BBP). On day 19 of embryogenesis, seeder embryos (n = 18) were inoculated with 4.5 × 104E. coli/mL+272 µg/mL tetracycline and segregated into mesh hatching bags. Twelve chicks per group were euthanized at hatch and at day 7 to evaluate the gastrointestinal composition of total GNB or total aerobic pasteurized bacteria. Also, in trial 2, ceca content from five chickens at day 7 were collected to evaluate microbiota composition. Embryos inoculated with BBP showed a significant (P < 0.05) reduction in the total number of GNB at day-of-hatch (DOH) and day 7. Probiotic treatment increased BW at DOH and day 7, and BW gain (days 0 to 7) when compared with Control chickens. Proteobacteria phylum was significantly reduced, while the Firmicutes was significantly increased by the BBP as compared to the Control (P < 0.05). At family level, Enterobacteriaceae was significantly decreased, while the Lachnospiraceae was significantly elevated in the BBP as compared to the Control group (P < 0.05). The genus Oscillospira was significantly enriched in the BBP group, whereas the unidentified genus of family Enterobacteriaceae in the Control group (P < 0.05). The BBP group increased the bacterial species richness, although there was no significant difference between treatments (P > 0.05). Interestingly, beta diversity showed a significant difference in bacterial community structure between Control and BBP groups (P < 0.05). The results of the present study suggest that in ovo administration of a BBP can reduce the severity of virulent E. coli horizontal transmission and infection of broiler chickens during hatch. The reduction in the severity of the transmission and infection by the BPP might be achieved through alterations of microbiota composition and its community structure.


Assuntos
Bacillus/química , Galinhas , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Óvulo/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Probióticos/farmacologia , Animais , Animais Recém-Nascidos , Transmissão de Doença Infecciosa , Escherichia coli/patogenicidade , Escherichia coli/fisiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Doenças das Aves Domésticas/microbiologia , Probióticos/administração & dosagem , Virulência
12.
Fish Shellfish Immunol ; 94: 175-189, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499198

RESUMO

Acute hepatopancreatic necrosis disease (AHPND), a serious disease caused by some Vibrio spp., impacts the Pacific white shrimp industry worldwide, especially in Thailand. To effectively overcome this problem, efficacious probiotic candidates were isolated from shrimp farms near coastal areas. The isolated Bacillus probiotics were screened for their ability to control pathogenic Vibrio spp. and various V. parahaemolyticus AHPND (VPAHPND) strains. Among the obtained probiotics, Bacillus subtilis AQAHBS001, which broadly inhibited various strains of VPAHPND, was evaluated on a laboratory scale in water-soluble and feed applications of viable probiotic. The water addition of 1 × 103-1 × 105 CFU/mL of this probiotic effectively reduced total ammonia but did not improve shrimp growth and resistance to VPAHPND. However, feed supplemented with the selected probiotic at 1 × 107 and 1 × 109 CFU/kg diet and provided to shrimp continuously for 5 weeks efficiently improved growth, as indicated by significant final weight gain, average daily growth, specific growth rates and feed conversion ratios. Additionally, this probiotic significantly elevated immune responses through phagocytic activity and clearance efficiency and enhanced the expression of the prophenoloxidase, lysozyme, and anti-lipopolysaccharide factor genes. Furthermore, B. subtilis AQAHBS001 obviously improved midgut characteristics by increasing microvilli and intestinal wall thickness. Finally, this probiotic evidently improved resistance to VPAHPND.


Assuntos
Bacillus/química , Imunidade Inata/efeitos dos fármacos , Penaeidae/imunologia , Probióticos/farmacologia , Vibrio parahaemolyticus/fisiologia , Ração Animal/análise , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Dieta , Relação Dose-Resposta a Droga , Penaeidae/efeitos dos fármacos , Penaeidae/crescimento & desenvolvimento , Penaeidae/microbiologia , Probióticos/administração & dosagem , Distribuição Aleatória , Qualidade da Água
13.
J Sci Food Agric ; 99(15): 6903-6910, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31415094

RESUMO

BACKGROUND: Bacillus thuringiensis (Bt) synthesizes Cry1Ac protein, which is toxic to many lepidopteran pests, and the cry1ac gene has been expressed in several transgenic crop plants. The Cry1Ac protein has been isolated from Bt kurstaki HD73 and purified to homogeneity. Polyclonal antibodies were raised against purified Cry1Ac in rabbits and goat. Sandwich ELISA was developed for Cry1Ac using goat IgG as a coating antibody, and affinity-purified rabbit IgG as the primary antibody. RESULTS: The sensitivity of the assay was in the range of 0.47-1000 ng. It was subsequently employed in validating biological samples. Fifteen different cotton-seed samples were screened: 12 were found to be Bt positive and 3 Bt negative. The CS7 seeds showed the highest Bt content of 8.51 ± 0.45 µg g-1 , followed by CS8 (6.0 ± 0.02 µg g-1 ), CS15 (5.9 ± 0.03 µg g-1 ), CS9 (5.5 ± 0.05 µg g-1 ), and CS10 (4.83 ± 0.013 µg g-1 ). The CS5 seeds showed Bt content of 3.6 ± 0.21 µg g-1 . The F2 generation, CS6 (Kaveri seeds) showed lower Bt content (2.9 ± 0.06 µg g-1 ). The CL5 samples showed Cry1Ac content of 0.99 ± 0.009 µg g-1 . The amount of Cry1Ac protein in leaves, stem, and roots of germinated Bt cotton plants (CS10 and CS4) were 1.76 ± 0.15 µg g-1 , 1.9 ± 0.01 µg g-1 , 2.0 ± 0.1 µg g-1 , and 1.6 ± 0.15 µg g-1 , 1.9 ± 0.01 µg g-1 , and 2.0 ± 0.01 µg g-1 dry tissue, respectively. CONCLUSION: The method developed can be used for screening the expression levels of Cry1Ac in different transgenic Bt cultivars and also spurious Bt cotton seeds procured by farmers. © 2019 Society of Chemical Industry.


Assuntos
Bacillus/química , Endotoxinas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Gossypium/química , Plantas Geneticamente Modificadas/química , Animais , Anticorpos/análise , Anticorpos/imunologia , Bacillus/metabolismo , Endotoxinas/imunologia , Endotoxinas/metabolismo , Gossypium/genética , Gossypium/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Coelhos , Sementes/química , Sementes/genética , Sementes/metabolismo
14.
J Microbiol ; 57(10): 900-909, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463786

RESUMO

In the present study, a laccase gene (BaLc) from a lignin degrading bacterium, Bacillus atrophaeus, has been cloned and expressed in Escherichia coli. The optimal catalytic activity of the protein was achieved at 5.5 pH and 35°C temperature, measured by oxidation of ABTS. The Km and Vmax values were determined as 1.42 mM and 4.16 µmole/min, respectively. To achieve the enzyme recovery, the biocatalyst (BaLc) was covalently attached onto the functionalized iron magnetic-nanoparticles. The nanoparticles were characterized by zeta-potential and FTIR analyses. The immobilized BaLc enzyme was physico-kinetically characterized, exhibiting retention of 60% of the residual activity after ten reaction cycles of ABTS oxidation. The immobilized biocatalyst system was tested for its biotechnological exploitability in plant juice processing, achieving 41-58% of phenol reduction, 41-58% decolorization, 50-59% turbidity reduction in the extracts of banana pseudo-stem and sweet sorghum stalk, and apple fruit juice. This is the first study to demonstrate the use of nanoparticle-laccase conjugate in juice clarification. The findings suggest that B. atrophaus laccase is a potential catalytic tool for plant juice bioprocessing activities.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/química , Lacase/química , Bacillus/química , Biocatálise , Estabilidade Enzimática , Enzimas Imobilizadas/química , Manipulação de Alimentos , Sucos de Frutas e Vegetais/análise , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas
15.
Fish Shellfish Immunol ; 93: 1047-1055, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31425831

RESUMO

Nowadays, there is no suitable treatment for vibriosis in groupers. So an eco-efficient and environmentally friendly treatment is necessary for the grouper industry. Probiotic-feeding has been a promising strategy to control the bacterial pathogens in aquaculture. A new Bacillus velezensis strain named K2 was isolated from the intestinal tract of healthy grouper, and exhibited wide antimicrobial spectrum of against fish pathogens, including Vibrio harveyi, Vibrio alginolyticus, Aeromonas hydrophila, Aeromonas veronii, Aeromonas caviae, Enterococcus casseliflavus and Lactococcus garvieae. Moreover, results of the safety of B. velezensis K2 showed that intraperitoneal injection of K2 in healthy grouper did not cause any pathological abnormality or death, indicating this bacteria could be considered as a candidate probiotic in aquaculture. Groupers were fed with the diets containing 1 × 107 cfu/g of B. velezensis K2 for 4 weeks. Various immune parameters were examined at 1, 2, 3, and 4 weeks of post-feeding. Results showed that diets supplemented with K2 significantly increased serum acid phosphatase (ACP) activity (P < 0.05). Results of the mRNA expression of immune-related genes in the head kidney of hybrid grouper showed that the expression of lysozyme gene was significantly upregulated after 1 and 2 weeks of feeding (P < 0.05). A significant up-regulation of the expression of piscidin, IgM and MyD88 were detected at day 21, whereas the TLR3 and TLR5 showed lower expression compared to the controls during 21 days, and a significant decrease of TLR3 gene was found at day 28 (P < 0.05). After challenge with V. harveyi, the survival rate of fish administrated with the strain K2 for 28 days was signifiacantly higher than the controls without this strain (P < 0.05). These results collectively suggest that B. velezensis K2 is a potential probiotic species to improve health status and disease resistance and can be developed as a probiotic agent in grouper industry.


Assuntos
Bacillus/química , Bass/imunologia , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Probióticos/farmacologia , Ração Animal/análise , Animais , Bass/crescimento & desenvolvimento , Dieta/veterinária , Distribuição Aleatória , Vibrio/efeitos dos fármacos , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
16.
Pak J Pharm Sci ; 32(3): 969-972, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31278708

RESUMO

Marine environment continues to be a huge source of pharmacologically active compounds that cure deadly disease. This research investigates the bioactive efficacy of bacteria isolated from surface of the coral, Junceella juncea (Pallas, 1766). 128 bacterial strains were isolated from the coral Junceella juncea from Tuticorin coast, Gulf of Mannar region, south east coast of India. The strains were tested against selected five human pathogens. Initial screening shows that the strain SG3 was found to exhibit broad spectral activity inhibiting Staplylococcus aureus. Also, twenty other strains were found to be active against various pathogens. Based on 16S rRNA sequencing and phylogenetic identification, the stain SG3 was identified to fell under the genera Bacillus. The ethanol precipitated of the culture broth (SG3) was done and its activity was noted. Mass spectrophotometry (MALDI-TOF) analysis has shown that the mass of the molecules ranged from 1225 Da to 1927 Da. Thus the marine bacteria isolated from corals are a potential source of novel bioactive agents and other natural products. Epibiotic bacteria also direct future isolation of peptide anti-MRSA compounds from marine source.


Assuntos
Antozoários/microbiologia , Antibacterianos/farmacologia , Bacillus/isolamento & purificação , Filogenia , Animais , Bacillus/química , Bacillus/genética , Bacillus/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Índia , RNA Ribossômico 16S , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Staphylococcus aureus/efeitos dos fármacos
17.
Prep Biochem Biotechnol ; 49(9): 891-899, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244362

RESUMO

The novel technology of biological carbon sequestration using microbial enzymes have numerous advantages over conventional sequestration strategies. In the present study, extracellular carbonic anhydrase (CA) producing bacteria were isolated from water samples in the Arabian Sea, India. A potential isolate, Bacillus safensis isolate AS-75 was identified based on 16S rDNA sequence analysis. The culture conditions suitable for CA production were 32 °C incubation temperature with 4% NaCl and 10 mM Zn supplementation. Experimental optimization of culture conditions enhanced enzyme activity to 265 U mL-1. CA specific gene was characterized and based on the analysis, the CA of B. safensis isolate AS-75 was a leucine (11.3%) with α-helices as the dominant component in its secondary structure. Based on soil microcosm studies, CA could sequester CO2 by 95.4% ± 0.11% in sterilized soil with enzyme microcosm. Hence, the application of enzyme was found to be more effective in removing CO2.


Assuntos
Bacillus/enzimologia , Dióxido de Carbono/metabolismo , Anidrases Carbônicas/metabolismo , Água do Mar/microbiologia , Sequência de Aminoácidos , Bacillus/química , Bacillus/metabolismo , Anidrases Carbônicas/química , Anidrases Carbônicas/isolamento & purificação , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Cinética , Modelos Moleculares , Microbiologia do Solo , Temperatura
18.
J Microbiol Biotechnol ; 29(6): 887-896, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31216842

RESUMO

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based pathogen identification relies on the ribosomal protein spectra provided in the proprietary database. Although these mass spectra can discern various pathogens at species level, the spectra-based method still has limitations in identifying closely-related microbial species. In this study, to overcome the limits of the current MALDI-TOF MS identification method using ribosomal protein spectra, we applied MALDI-TOF MS of low-mass profiling to the identification of two genetically related Bacillus species, the food-borne pathogen Bacillus cereus, and the insect pathogen Bacillus thuringiensis. The mass spectra of small molecules from 17 type strains of two bacilli were compared to the morphological, biochemical, and genetic identification methods of pathogens. The specific mass peaks in the low-mass range (m/z 500- 3,000) successfully identified various closely-related strains belonging to these two reference species. The intensity profiles of the MALDI-TOF mass spectra clearly revealed the differences between the two genetically-related species at strain level. We suggest that small molecules with low molecular weight, 714.2 and 906.5 m/z can be potential mass biomarkers used for reliable identification of B. cereus and B. thuringiensis.


Assuntos
Bacillus cereus/química , Bacillus cereus/classificação , Proteínas de Bactérias/química , Técnicas de Tipagem Bacteriana/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Bacillus/química , Bacillus/classificação , Bacillus/ultraestrutura , Bacillus cereus/ultraestrutura , Bacillus thuringiensis/química , Bacillus thuringiensis/classificação , Bacillus thuringiensis/ultraestrutura , Biomarcadores/química , DNA Bacteriano/genética , Doenças Transmitidas por Alimentos/microbiologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
19.
Curr Microbiol ; 76(9): 1028-1037, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31187206

RESUMO

Given antibiotic resistance in pathogens, finding antibiotics from new sources is always a topic of interest to scientists. In the present study, among various isolates from the Persian Gulf coastal area, the strain RP137 was selected as producer of antibacterial compound. Morphological and biochemical studies along with 16S rDNA sequencing showed that strain RP137 belongs to Bacillus genus and was tentatively named Bacillus velezensis strain RP137. The effect of various carbon and nitrogen sources on optimizing the production of antibacterial compound showed that the low-cost rice starch and potassium nitrate supply to the strain RP137 caused producing of 86.0 ± 8.7 µg/mL extract having the antibacterial activity. The fractionation of the primary methanol extract in different solvents followed by reversed-phase HPLC obtained a pure antibacterial-active sample, S-137-R. Structural analysis of the purified S-137-R with the help of FTIR, HR-MS, 1H-NMR, and 13C-NMR showed that the S-137-R compound is classified as aminoglycoside. Minimum inhibition concentration (MIC) of the pure compound for Gram-positive bacteria, Staphylococcus aureus and methicillin resistant Staphylococcus aureus, showed an average antibacterial effect of about 80 µg/mL and 150 µg/mL, respectively and for Pseudomonas aeruginosa (100 µg/mL), while having very little toxic effect on E. coli. Moreover, low cytotoxicity effect of the S-137-R on cancerous and normal cells as well as the low intensity of the hemolysis of red blood cells in higher concentrations of S-137-R make it an ideal candidate for further structure-activity relationship assessments towards its medical applications.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Bacillus/química , Bacillus/isolamento & purificação , Água do Mar/microbiologia , Aminoglicosídeos/química , Aminoglicosídeos/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Bacillus/classificação , Bacillus/metabolismo , Escherichia coli/efeitos dos fármacos , Oceano Índico , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
20.
Int J Biol Macromol ; 134: 1085-1096, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31129215

RESUMO

Bio-plastic synthesis from renewable and cheap agro-based materials is a sustainable solution for replacing conventionally produced plastic with environmental contamination. The current study was aimed at screening and characterization of Polyhydroxyalkanoates (PHA) producing bacterial isolates, evaluation of their potential and recovery of PHA using the isolates. The PHA compounds were characterized using FT-IR. Based on 16SrRNA sequence analyses the isolates were designated as Bacillus sp. BPPI-14 and Bacillus sp. BPPI-19. The isolates were gram-positive, rod-shaped, endospore former, and citrate test positive. Intracellular PHA granules were observed when these isolates were stained with Sudan black B (SBB) and Nile blue A (NBA) preliminary and specific staining dyes, respectively. Effect of pH, temperature and carbon sources on the PHA production by the isolates BPPI-14 and BPPI-19 was studied. Maximum PHA production was recorded for Glucose (49.46±2.79%) by Bacillus sp. BPPI-14 and followed by molasses (45.86±2.17%) by Bacillus sp. BPPI-19, respectively at 37°C and pH7. The obtained PHA polymers were confirmed by preparation of plastic films for both the isolates. Fourier transform infrared spectrum for BPPI-14 and BPPI-19 showed the peak (carboxylic acid group) at 1706-1719.39cm-1 was a characteristic feature of PHA and corresponds functional group (C=O).


Assuntos
Bacillus/química , Plásticos , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/isolamento & purificação , Resíduos , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Fenômenos Químicos , Concentração de Íons de Hidrogênio , Filogenia , RNA Ribossômico 16S/genética
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