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1.
Virol J ; 18(1): 202, 2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627307

RESUMO

BACKGROUND: The effect of SARS-CoV-2 on existing respiratory pathogens in circulation remains uncertain. This study aimed to assess the impact of SARS-CoV-2 on the prevalence of respiratory pathogens among hospitalized children. METHODS: This study enrolled hospitalized children with acute respiratory infections in Shenzhen Children's Hospital from September to December 2019 (before the COVID-19 epidemic) and those from September to December 2020 (during the COVID-19 epidemic). Nasopharyngeal swabs were collected, and respiratory pathogens were detected using multiplex PCR. The absolute case number and detection rates of 11 pathogens were collected and analyzed. RESULTS: A total of 5696 children with respiratory tract infection received multiplex PCR examination for respiratory pathogens: 2298 from September to December 2019 and 3398 from September to December 2020. At least one pathogen was detected in 1850 (80.5%) patients in 2019, and in 2380 (70.0%) patients in 2020; the detection rate in 2020 was significantly lower than that in 2019.The Influenza A (InfA) detection rate was 5.6% in 2019, but 0% in 2020. The detection rates of Mycoplasma pneumoniae, Human adenovirus, and Human rhinovirus also decreased from 20% (460), 8.9% (206), and 41.8% (961) in 2019 to 1.0% (37), 2.1% (77), and 25.6% (873) in 2020, respectively. In contrast, the detection rates of Human respiratory syncytial virus, Human parainfluenza virus, and Human metapneumovirus increased from 6.6% (153), 9.9% (229), and 0.5% (12) in 2019 to 25.6% (873), 15.5% (530), and 7.2% (247) in 2020, respectively (p < 0.0001). CONCLUSIONS: Successful containment of seasonal influenza as a result of COVID-19 control measures will ensure we are better equipped to deal with future outbreaks of both influenza and COVID-19.Caused by virus competition, the detection rates of Human respiratory syncytial virus, Human parainfluenza virus, and Human metapneumovirus increased in Shenzhen,that reminds us we need to take further monitoring and preventive measures in the next epidemic season.


Assuntos
Antibiose , COVID-19/epidemiologia , Doenças Respiratórias/epidemiologia , SARS-CoV-2/isolamento & purificação , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , Adolescente , COVID-19/virologia , Criança , Criança Hospitalizada , Pré-Escolar , China , Enterovirus/genética , Enterovirus/isolamento & purificação , Feminino , Humanos , Lactente , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Masculino , Metapneumovirus/genética , Metapneumovirus/isolamento & purificação , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/isolamento & purificação , Nasofaringe/microbiologia , Nasofaringe/virologia , Prevalência , Vírus Sinciciais Respiratórios/genética , Vírus Sinciciais Respiratórios/isolamento & purificação , Doenças Respiratórias/microbiologia , Doenças Respiratórias/virologia , Respirovirus/genética , Respirovirus/isolamento & purificação , SARS-CoV-2/genética
2.
Life Sci ; 285: 120003, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34599936

RESUMO

AIMS: Indole-3-propionic acid (IPA) is a natural product from human microbiota, exhibiting diverse biological activities. The study focused on investigating the antibacterial mode of action(s) triggered by IPA in Escherichia coli. Separate influence of nitric oxide (NO) and each reactive oxygen species, including superoxide anion (O2-), hydrogen peroxide (H2O2), hydroxyl radical (OH-), was specifically analyzed throughout the process. MAIN METHODS: The generation of respective reactive oxygen species (ROS), NO, and ONOO- was conducted using flow cytometer using different dyes. Further analysis of separate influences was held based on usage of each scavenger: sodium pyruvate, thiourea, tiron, and L-NAME. Oxidative cell damage was observed through the detection of glutathione depletion and lipid peroxidation. DNA fragmentation and membrane depolarization were observed by TUNEL and DiBAC4(3) staining agent. Finally, Annexin V/PI and FITC-VAD-FMK were applied to detect apoptosis-like death. KEY FINDINGS: IPA exhibited antibacterial activity in E. coli through the accumulation of ROS, NO, ONOO-, and DNA damage, eventually leading to apoptosis-like death. NO and O2- exerted the most potent influence on oxidative damage of E. coli, whereas H2O2 accounts for the least impact. Moreover, the results reveal the major contribution of ONOO- in IPA-induced apoptosis-like death in E. coli. SIGNIFICANCE: This is the first study that introduces the antibacterial activity and apoptosis-like death induced by IPA and suggests the possibility of being an alternative for current antibiotics. Furthermore, the distinct influence of each ROS and NO was analyzed to investigate their contribution to oxidative damage leading to bacterial apoptosis-like death.


Assuntos
Antibiose , Apoptose , Escherichia coli/fisiologia , Indóis/metabolismo , Microbiota/fisiologia , Óxido Nítrico/fisiologia , Propionatos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fragmentação do DNA , Escherichia coli/efeitos dos fármacos , Glutationa/metabolismo , Indóis/farmacologia , Peroxidação de Lipídeos , Microbiota/efeitos dos fármacos , Propionatos/farmacologia
3.
Syst Appl Microbiol ; 44(5): 126244, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34392062

RESUMO

Marine sponges represent a rich source of uncharacterized microbial diversity, and many are host to microorganisms that produce biologically active specialized metabolites. Here, a polyphasic approach was used to characterize two Actinobacteria strains, P01-B04T and P01-F02, that were isolated from the marine sponges Geodia barretti (Bowerbank, 1858) and Antho dichotoma (Esper, 1794), respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains P01-B04T and P01-F02 are closely related to Streptomyces beijiangensis DSM 41794T, Streptomyces laculatispora NRRL B-24909T, and Streptomyces brevispora NRRL B-24910T. The two strains showed nearly identical 16S rRNA gene sequences (99.93%), and the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) relatedness values were 99.96% and 99.6%, respectively, suggesting that these strains are affiliated with the same species. Chemotaxonomic and culture characteristics of both strains were also consistent with the genus Streptomyces, while phenotypic properties, genome-based comparisons, and phylogenomic analyses distinguished strains P01-B04T and P01-F02 from their closest phylogenetic relatives. In silico analysis predicted that the 8.9 Mb genome of P01-B04T contains at least 41 biosynthetic gene clusters (BGCs) encoding secondary metabolites, indicating that this strain could express diverse bioactive metabolites; in support of this prediction, this strain expressed antibacterial activity against Gram-positive bacteria including a clinical isolate of methicillin-resistant Staphylococcus aureus (MRSA) EAMC30. Based on these results, the marine sponge-associated isolates represent a novel species of the genus Streptomyces, for which the name Streptomyces poriferorum sp. nov. is proposed, with P01-B04T (=DSM 111306T = CCM 9048T) as the type strain.


Assuntos
Antibiose , Poríferos , Streptomyces , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Staphylococcus aureus Resistente à Meticilina , Família Multigênica , Hibridização de Ácido Nucleico , Filogenia , Poríferos/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/classificação , Streptomyces/isolamento & purificação
4.
5.
Food Microbiol ; 100: 103863, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34416963

RESUMO

In the present work, we evaluated the effects of a mixture of biocontrol agents against two toxigenic strains of Penicillium expansum isolated in Argentine Patagonia from pome fruits. The two strains, INTA-5 and INTA-10, were previusly selected among ten strains coming from the Alto Valle (Rio Negro-Argentina) for their high production of patulin. For the biocontrol, Kosakonia radicincitans, Cryptococcus laurentii, and Rhodosporidium fluviale were tested in vitro experiments on Potato Dextrose Agar (PDA) dishes against the INTA-5 and INTA-10 strains. The bacterium K. radicincitans and the yeast C. laurentii were selected to be used in a mixture due to their capacity to control the fungus and reduce the mycotoxin severely. In vitro assays with the mixture showed a high antagonism against P. expansum INTA-5 and INTA-10, at 21 d of incubation at 25 °C and a patulin reduction of 98%. The mixture of microorganisms was also effective in apples stored at 25 °C for 10 d and 4 °C for 30 d. At cold storage, the mixture controlled moderately the development of rot and decreased patulin concentration. At 25 °C, the pathogen's optimal growth temperature, the mixture of Biological Control Agent (BCAs) assured both the control of rot and decrease of patulin concentration. The combination of two microorganisms, with different requirements and abilities, resulted in a mix with a strong antagonism against P. expansum with the capability to decrease the patulin concentration. Treatment with the selected mixture could be a good option for controlling strains with different behaviours and in different environmental conditions.


Assuntos
Antibiose , Agentes de Controle Biológico/farmacologia , Cryptococcus/fisiologia , Enterobacteriaceae/fisiologia , Malus/microbiologia , Patulina/biossíntese , Penicillium/efeitos dos fármacos , Penicillium/metabolismo , Doenças das Plantas/microbiologia , Frutas/microbiologia
6.
Food Microbiol ; 100: 103868, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34416967

RESUMO

Kimchi is one of the primary sources of high sodium content in the Korean diet. Low-sodium kimchi is commercially manufactured to minimize the health effects of high salt. We investigated the influence of lactic acid bacteria (LAB) as starter culture in combination with 1% or 2.5% salt on the survival of pathogenic Escherichia coli and physicochemical properties of kimchi during fermentation at 10 °C and 25 °C. Among ten strains of LAB isolated from kimchi, Leuconostoc mesenteroides (KCTC 13374) and Lactobacillus plantarum (KCTC 33133) exhibited antimicrobial activities against pathogenic E. coli (EPEC, ETEC, and E. coli O157:H7) and strong tolerance to low pH (2 and 3) and 0.3% bile salts. Thus, L. mesenteroides and L. plantarum were used as starter cultures for kimchi that contained 1% and 2.5% salt. All pathogenic E. coli strains survived in kimchi regardless of starter cultures or salt concentration for over 15 days at 10 °C, but they died off within 4 days at 25 °C. Survival of pathogenic E. coli was better in naturally fermented kimchi (titratable acidity:0.65%) than kimchi fermented with starter cultures (titratable acidity:1.0%). At 10 °C, the average delta value of E. coli O157:H7 (16.15 d) was smaller than those of EPEC (20.76 d) and ETEC (20.20 d) in naturally fermented kimchi. Overall, survival ability of E. coli O157:H7 was lower than EPEC and ETEC, although differences were not significant. Reduced salt concentration from 2.5% to 1% in kimchi did not affect the growth of LAB and the fermentation period. Pathogenic E. coli died at a faster rate in kimchi fermented with starter cultures and 1% salt than in naturally fermented kimchi with 2.5% salt.


Assuntos
Brassica/microbiologia , Escherichia coli Enteropatogênica/crescimento & desenvolvimento , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Escherichia coli O157/crescimento & desenvolvimento , Alimentos e Bebidas Fermentados/microbiologia , Lactobacillales/metabolismo , Cloreto de Sódio/metabolismo , Antibiose , Brassica/química , Contagem de Colônia Microbiana , Escherichia coli Enteropatogênica/fisiologia , Escherichia coli Enterotoxigênica/fisiologia , Escherichia coli O157/fisiologia , Alimentos e Bebidas Fermentados/análise , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Cloreto de Sódio/análise
7.
Food Microbiol ; 100: 103872, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34416969

RESUMO

This study aimed to evaluate technological (acidification, proteolysis, lipolysis, resistance to low pH, NaCl, and bile salts) and biopreservation (antimicrobial activity against foodborne pathogens) features of 1002 LAB by high throughput screening (HTS) methods. The LAB was isolated from 11 types of Brazilian artisanal cheeses (BAC) marketed in the main 5 producing regions. Remarkable intra-species variability in acidification rates have been found, which was most pronounced between isolates from Mina's artisanal cheeses, Caipira and Coalho cheeses. Lacticaseibacillus paracasei and Levilactobacillus brevis showed the fastest acidification rate; however, all isolates showed slower acidification rates than a lactococcal control strain (4.3 × lower). When testing inhibitory effects, > 75% of LAB isolates could inhibit the growth of Staphylococcus aureus ATCC 19095 and Listeria monocytogenes ATCC 7644. Two of these isolates, identified as Lactiplantibacillus plantarum and Lentilactobacillus buchneri, the sterile and neutral supernatants alone, were sufficient to inhibit L. monocytogenes growth. Principal component analysis (PCA) allowed the identification of functional groups based on proteolytic and lipolytic activity, osmotic stress resistance, and inhibition of L. monocytogenes. The type of cheese the isolates were recovered from influenced properties such as anti-listerial compounds and lipolytic enzyme production. The use of HTS and multivariate statistics allowed insights into a diverse set of LAB technological and biopreservation properties. These findings allow a profound knowledge of the heterogeneity of a large set of isolates, which can be further used to design starter cultures with varied and combined properties, such as biopreservation and technological features. Besides that, HTS makes it possible to analyze a vast panel of LAB strains, reducing costs and time within laboratory analysis, while avoiding the loss of information once all LAB are tested at the same time (differently from the traditional labor-intensive approach, in which a few numbers of strains is tested per time).


Assuntos
Queijo/microbiologia , Lactobacillales/isolamento & purificação , Antibiose , Brasil , Ensaios de Triagem em Larga Escala , Lactobacillales/classificação , Lactobacillales/genética , Lactobacillales/fisiologia , Listeria monocytogenes/crescimento & desenvolvimento , Filogenia
8.
Vet Microbiol ; 261: 109187, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34399296

RESUMO

Chicken colibacillosis is caused by avian pathogenic Escherichia coli (APEC), and results in huge economic losses to the poultry industry. With the investigation of the gut-lung axis, more studies have demonstrated the important role of gut microbiota in lung inflammation. The precise role of the gut microbiota in chickens-associated colibacillosis, however, is unknown. Thus, this study assessed the function of the gut microbiota in the chicken defense against APEC infection. Chicken gut microbiota was depleted by drinking water with a mixture of antibiotics (Abx), and subsequently, a model of colibacillosis was established by the intranasal perfusion of APEC. The results showed that gut microbiota protects the chicken challenge by APEC from aggravated lung histopathologic injury, up-regulated pro-inflammatory cytokine production, and increased bacterial load in lung tissues compared with controls. In addition, the air-blood barrier permeability was significantly increased in gut microbiota-depleted chickens compared to the control chickens after challenge with APEC. Furthermore, feeding acetate significantly inhibited the lung inflammatory response and the reduced air-blood permeability induced by APEC infection. The expression of free fatty acid receptor 2 (FFAR2), a receptor for acetate, was also increased in the lung after treatment with acetate. In conclusion, depletion of the gut microbiota resulted in increased susceptibility of chickens to APEC challenge, and gut microbiota derived acetate acted as a protective mediator during the APEC challenge. Novel therapeutic targets that focus on the gut microbiota may be effective in controlling colibacillosis in poultry.


Assuntos
Acetatos/metabolismo , Antibiose/fisiologia , Infecções por Escherichia coli/veterinária , Microbioma Gastrointestinal/fisiologia , Doenças das Aves Domésticas/microbiologia , Animais , Galinhas , Escherichia coli/fisiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle
9.
Pol J Microbiol ; 70(2): 235-243, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34349813

RESUMO

Lactobacillus plantarum BW2013 was isolated from the fermented Chinese cabbage. This study aimed to test the effect of this strain on the gut microbiota in BALB/c mice by 16S rRNA amplicon sequencing. The mice were randomly allocated to the control group and three treatment groups of L. plantarum BW2013 (a low-dose group of 108 CFU/ml, a medium-dose group of 109 CFU/ml, and a high-dose group of 1010 CFU/ml). The weight of mice was recorded once a week, and the fecal samples were collected for 16S rRNA amplicon sequencing after 28 days of continuous treatment. Compared with the control group, the body weight gain in the treatment groups was not significant. The 16S rRNA amplicon sequencing analysis showed that both the Chao1 and ACE indexes increased slightly in the medium-dose group compared to the control group, but the difference was not significant. Based on PCoA results, there was no significant difference in ß diversity between the treatment groups. Compared to the control group, the abundance of Bacteroidetes increased in the low-dose group. The abundance of Firmicutes increased in the medium-dose group. At the genus level, the abundance of Alloprevotella increased in the low-dose group compared to the control group. The increased abundance of Ruminococcaceae and decreased abundance of Candidatus_Saccharimonas was observed in the medium-dose group. Additionally, the abundance of Bacteroides increased, and Alistipes and Candidatus_Saccharimonas decreased in the high-dose group. These results indicated that L. plantarum BW2013 could ameliorate gut microbiota composition, but its effects vary with the dose.


Assuntos
Antibiose/fisiologia , Biodiversidade , Microbioma Gastrointestinal , Lactobacillus plantarum/fisiologia , Animais , Fezes/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Ribossômico 16S/genética
10.
Int J Mol Sci ; 22(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34202945

RESUMO

Trillions of microbes exist in the human body, particularly the gastrointestinal tract, coevolved with the host in a mutually beneficial relationship. The main role of the intestinal microbiome is the fermentation of non-digestible substrates and increased growth of beneficial microbes that produce key antimicrobial metabolites such as short-chain fatty acids, etc., to inhibit the growth of pathogenic microbes besides other functions. Intestinal microbiota can prevent pathogen colonization through the mechanism of colonization resistance. A wide range of resistomes are present in both beneficial and pathogenic microbes. Giving antibiotic exposure to the intestinal microbiome (both beneficial and hostile) can trigger a resistome response, affecting colonization resistance. The following review provides a mechanistic overview of the intestinal microbiome and the impacts of antibiotic therapy on pathogen colonization and diseases. Further, we also discuss the epidemiology of immunocompromised patients who are at high risk for nosocomial infections, colonization and decolonization of multi-drug resistant organisms in the intestine, and the direct and indirect mechanisms that govern colonization resistance to the pathogens.


Assuntos
Antibiose , Suscetibilidade a Doenças , Microbioma Gastrointestinal , Interações Hospedeiro-Patógeno , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/etiologia , Resistência a Múltiplos Medicamentos , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Sepse/etiologia
11.
J Basic Microbiol ; 61(8): 745-756, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34228381

RESUMO

Antagonistic bacteria can act as biocontrol agents against various phytopathogens. Recently, Arthrobacter spp. demonstrated antifungal activity, but were not further characterized. In this study, the antimicrobial activity of Arthrobacter humicola strains M9-1A, M9-2, and M9-8, and Arthrobacter psychrophenolicus strain M9-17 were evaluated against nine plant pathogens in vitro, and their cell-free filtrates were additionally assessed for inhibition of Alternaria alternata and suppression of black mold disease on tomato fruit. Results indicated that A. humicola M9-1A and A. psychrophenolicus M9-17 were the most inhibitory, reducing growth of seven of the pathogens studied. Cell-free filtrates of A. psychrophenolicus M9-17 reduced the growth of most pathogens. All cell-free bacterial filtrates, except those from A. humicola M9-2, suppressed black mold on tomato fruit. Disk diffusion assays with ethyl acetate soluble culture filtrate extracts of all bacteria reduced the mycelial growth of A. alternata. Clear inhibition zones were observed for A. psychrophenolicus M9-17 extracts using drop bioassays. The antifungal compound N-acetyltryptamine was purified and characterized from the A. psychrophenolicus M9-17 cell-free ethyl acetate soluble extract. This study suggests that antibiosis may play a key role in the antimicrobial activity of Arthrobacter spp.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Arthrobacter/isolamento & purificação , Arthrobacter/metabolismo , Compostagem , Alternaria/efeitos dos fármacos , Antibiose/efeitos dos fármacos , Antifúngicos/química , Antifúngicos/farmacologia , Frutas/microbiologia , Lycopersicon esculentum/microbiologia , Micrococcaceae , Doenças das Plantas/microbiologia
12.
J Microbiol ; 59(7): 627-633, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34212287

RESUMO

Bacillus velezensis is a plant growth-promoting bacterium that can also inhibit plant pathogens. However, based on its properties, it is emerging as a probiotic in animal feed. This review focuses on the potential characteristics of B. velezensis for use as a probiotic in the animal feed industry. The review was conducted by collecting recently published articles from peer-reviewed journals. Google Scholar and PubMed were used as search engines to access published literature. Based on the information obtained, the data were divided into three groups to discuss the (i) probiotic characteristics of B. velezensis, (ii) probiotic potential for fish, and (iii) the future potential of this species to be developed as a probiotic for the animal feed industry. Different strains of B. velezensis isolated from different sources were found to have the ability to produce antimicrobial compounds and have a beneficial effect on the gut microbiota, with the potential to be a candidate probiotic in the animal feed industry. This review provides valuable information about the characteristics of B. velezensis, which can provide researchers with a better understanding of the use of this species in the animal feed industry.


Assuntos
Ração Animal/microbiologia , Bacillus , Probióticos , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Antibiose , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Bacillus/genética , Bacillus/fisiologia , Peixes , Microbioma Gastrointestinal , Genes Bacterianos , Aves Domésticas , Metabolismo Secundário/genética
13.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204294

RESUMO

Persistent infection with High Risk-Human Papilloma Viruses (HR-HPVs) is a primary cause of cervical cancer worldwide. Vaginal-dysbiosis-associated bacteria were correlated with the persistence of HR-HPVs infection and with increased cancer risk. We obtained strains of the most represented bacterial species in vaginal microbiota and evaluated their effects on the survival of cervical epithelial cells and immune homeostasis. The contribution of each species to supporting the antiviral response was also studied. Epithelial cell viability was affected by culture supernatants of most vaginal-dysbiosis bacteria, whereas Lactobacillus gasseri or Lactobacillus jensenii resulted in the best stimulus to induce interferon-γ (IFN-γ) production by human mononuclear cells from peripheral blood (PBMCs). Although vaginal-dysbiosis-associated bacteria induced the IFN-γ production, they were also optimal stimuli to interleukin-17 (IL-17) production. A positive correlation between IL-17 and IFN-γ secretion was observed in cultures of PBMCs with all vaginal-dysbiosis-associated bacteria suggesting that the adaptive immune response induced by these strains is not dominated by TH1 differentiation with reduced availability of IFN-γ, cytokine most effective in supporting virus clearance. Based on these results, we suggest that a vaginal microbiota dominated by lactobacilli, especially by L. gasseri or L. jensenii, may be able to assist immune cells with clearing HPV infection, bypasses the viral escape and restores immune homeostasis.


Assuntos
Antibiose , Disbiose , Homeostase , Lactobacillus/fisiologia , Membrana Mucosa/imunologia , Membrana Mucosa/microbiologia , Vagina/imunologia , Vagina/microbiologia , Sobrevivência Celular , Citocinas/biossíntese , Células Epiteliais/metabolismo , Ácidos Graxos Voláteis/biossíntese , Feminino , Humanos , Vagina/metabolismo
14.
World J Microbiol Biotechnol ; 37(8): 143, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34328568

RESUMO

Antifungal and antibacterial activities of twenty-six combinations of lactic acid bacteria, propionibacteria, acetic acid bacteria and dairy yeasts inoculated in whey and milk were investigated. Associations including acetic acid bacteria were shown to suppress growth of the opportunistic yeast Candida albicans in well-diffusion assays. The protective effect of milk fermented with the two most promising consortia was confirmed in Caco-2 cell culture infected with C. albicans. Indeed, these fermented milks, after heat-treatment or not, suppressed lactate dehydrogenase release after 48 h while significant increase in LDH release was observed in the positive control (C. albicans alone) and with fermented milk obtained using commercial yogurt starter cultures. The analysis of volatile compounds in the cell-free supernatant using solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS) showed accumulation of significant amount of acetic acid by the consortium composed of Lactobacillus delbrueckii 5, Lactobacillus gallinarum 1, Lentilactobacillus parabuchneri 3, Lacticaseibacillus paracasei 33-4, Acetobacter syzygii 2 and Kluyveromyces marxianus 19, which corresponded to the zone of partial inhibition of C. albicans growth during well-diffusion assays. Interestingly, another part of anti-Candida activity, yielding small and transparent inhibition zones, was linked with the consortium cell fraction. This study showed a correlation between anti-Candida activity and the presence of acetic acid bacteria in dairy associations as well as a significant effect of two dairy associations against C. albicans in a Caco-2 cell model. These two associations may be promising consortia for developing functional dairy products with antagonistic action against candidiasis agents.


Assuntos
Candida/crescimento & desenvolvimento , Produtos Fermentados do Leite/microbiologia , Lactobacillales/metabolismo , Leite/microbiologia , Animais , Antibiose , Células CACO-2 , Bovinos , Produtos Fermentados do Leite/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactobacillales/química , Lactobacillales/classificação , Leite/química
15.
Sci Rep ; 11(1): 15007, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294848

RESUMO

Clostridioides difficile infection (CDI) represents the leading cause of nosocomial diarrhea worldwide and is associated with gut dysbiosis and intestinal damage. Clostridium butyricum MIYAIRI 588 (CBM 588) contributes significantly to reduce epithelial damage. However, the impacts of CBM 588 on antibacterial therapy for CDI are not clear. Here we show that CBM 588 enhanced the antibacterial activity of fidaxomicin against C. difficile and negatively modulated gut succinate levels to prevent C. difficile proliferation and downregulate tumor necrosis factor-α (TNF-α) producing macrophages in the colon lumina propria (cLP), resulting in a significant decrease in colon epithelial damage. Additionally, CBM 588 upregulated T cell-dependent pathogen specific immunoglobulin A (IgA) via interleukin (IL)-17A producing CD4+ cells and plasma B cells in the cLP, and Th17 cells in the cLP enhanced the gut epithelial barrier function. IL-17A and succinic acid modulations with CBM 588 enhance gut colonization resistance to C. difficile and protect the colon tissue from CDI.


Assuntos
Antibiose , Clostridioides difficile/fisiologia , Infecções por Clostridium/microbiologia , Clostridium butyricum/fisiologia , Metabolismo Energético , Imunomodulação , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Microbioma Gastrointestinal , Imunoglobulina A/imunologia , Interleucina-17/biossíntese , Camundongos , Modelos Biológicos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
16.
mBio ; 12(3): e0150221, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34182776

RESUMO

Previously, we documented that Stenotrophomonas maltophilia encodes a type IV secretion system (T4SS) that allows the organism to kill, in contact-dependent fashion, heterologous bacteria, including wild-type Pseudomonas aeruginosa. Bioinformatic screens based largely on the presence of both a C-terminal consensus sequence and an adjacent gene encoding a cognate immunity protein identified 13 potential antibacterial effectors, most of which were highly conserved among sequenced strains of S. maltophilia. The immunity proteins of two of these proved especially capable of protecting P. aeruginosa and Escherichia coli against attack from the Stenotrophomonas T4SS. In turn, S. maltophilia mutants lacking the putative effectors RS14245 and RS14255 were impaired for killing not only laboratory E. coli but clinical isolates of P. aeruginosa, including ones isolated from the lungs of cystic fibrosis patients. That complemented mutants behaved as wild type did confirmed that RS14245 and RS14255 are required for the bactericidal activity of the S. maltophilia T4SS. Moreover, a mutant lacking both of these proteins was as impaired as a mutant lacking the T4SS apparatus, indicating that RS14245 and RS14255 account for (nearly) all of the bactericidal effects seen. Utilizing an interbacterial protein translocation assay, we determined that RS14245 and RS14255 are bona fide substrates of the T4SS, a result confirmed by examination of mutants lacking both the T4SS and the individual effectors. Delivery of the cloned 14245 protein (alone) into the periplasm resulted in the killing of target bacteria, indicating that this effector, a putative lipase, is both necessary and sufficient for bactericidal activity. IMPORTANCE S. maltophilia is an increasingly important opportunistic pathogen. Inherently resistant to many antibiotics, S. maltophilia is often associated with lung infection, being, among other things, a complicating factor in cystic fibrosis patients. Moreover, it is a common form of coinfection in COVID-19 patients. In these various clinical settings and in natural habitats, S. maltophilia coexists with other pathogens, including P. aeruginosa. Previously, we documented that S. maltophilia possesses a T4SS that kills other bacteria, a notable observation given that most prior work on interbacterial competition has highlighted bactericidal effects of type VI secretion systems. By utilizing approaches ranging from bioinformatics to mutant analysis to protein translocation assays, we have now identified two substrates of the Stenotrophomonas T4SS that largely mediate the killing of pathogenic P. aeruginosa. These results represent a major advance in understanding S. maltophilia, the roles of T4SSs, concepts regarding clinically relevant, interbacterial competition, and activities of bactericidal effectors.


Assuntos
Antibiose/genética , Escherichia coli/metabolismo , Pseudomonas aeruginosa/metabolismo , Stenotrophomonas maltophilia/genética , Sistemas de Secreção Tipo IV/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Humanos , Stenotrophomonas maltophilia/metabolismo , Sistemas de Secreção Tipo IV/genética
17.
Arch Microbiol ; 203(7): 4161-4171, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34061232

RESUMO

The objective of this work was to determine the antibacterial effect of Lactobacillus plantarum strains of pork origin against Campylobacter coli strains, and to conduct experimental colonization pilot models in mice for both microorganisms. Inhibition assays allowed evaluation and selection of L. plantarum LP5 as the strain with the highest antagonistic activity against C. coli and with the best potential to be used in in vivo study. Adult 6-week-old female Balb/cCmedc mice were lodged in two groups. The treated group was administered with 9.4 log10CFU/2 times/wk of L. plantarum LP5. L. plantarum LP5 was recovered from the feces and cecum of the inoculated mice. However, when bacteria stopped being administered, probiotic counts decreased. Experimental colonization with C. coli was carried out in five groups of mice. All animals were treated with antibiotics in their drinking water to weaken the indigenous microbiota and to allow colonization of C. coli. Four groups were administered once with different C. coli strains (DSPV458: 8.49 log10CFU; DSPV567: 8.09 log10CFU; DSPV570: 8.46 log10CFU; DSPV541: 8.86 log10CFU, respectively). After 8 h, mice inoculated with different C. coli strains were colonized because the pathogen was detected in their feces. L. plantarum LP5 tolerated the gastrointestinal conditions of murine model without generating adverse effects on the animals. C. coli DSPV458 colonized the mice without causing infection by lodging in their digestive tract, thus generating a reproducible colonization model. Both models combined could be used as protection murine models against pathogens to test alternative control tools to antibiotics.


Assuntos
Antibiose , Campylobacter coli , Lactobacillus plantarum , Probióticos , Animais , Campylobacter coli/fisiologia , Fezes/microbiologia , Feminino , Trato Gastrointestinal/microbiologia , Lactobacillus plantarum/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Probióticos/metabolismo
18.
Sci Rep ; 11(1): 12963, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155274

RESUMO

Streptococcus mutans produces bacteriocins that show antibacterial activity against several bacteria. However, comprehensive analysis of these bacteriocins has not been well done. In this study, we isolated 125 S. mutans strains from volunteers and determined their whole genome sequence. Based on the genome analysis, the distribution of each bacteriocin gene (mutacins I-IV, K8 and Smb) was investigated. We found 17, 5, and 2 strains showing 100% matches with mutacin I, mutacin II and mutacin III, respectively. Five mutacin III-positive strains had 2 mismatches compared to mature mutacin III. In 67 mutacin IV-positive strains, 38 strains showed 100% match with mutacin IV, while 29 strains showed some variations. In 23 mutacin K8- and 32 mutacin Smb-positive strains, all except one mutacin K8-positive strain showed 100% match with the mature peptides. Among 125 strains, 84 (65.1%), 26 (20.2%), and 5 (3.9%) strains were positive for one, two and three bacteriocin genes, respectively. Then, the antibacterial activity against oral streptococci and other oral bacterial species was investigated by using bacteriocin gene single-positive strains. Each bacteriocin gene-positive strain showed a different pattern of antibacterial activity. These results speculate that individual S. mutans strains may affect the bacterial composition of dental plaques.


Assuntos
Bacteriocinas/genética , Streptococcus mutans/genética , Streptococcus mutans/metabolismo , Sequência de Aminoácidos , Antibacterianos/biossíntese , Antibiose , Bacteriocinas/química , Bacteriocinas/metabolismo , Regulação Bacteriana da Expressão Gênica , Humanos , Testes de Sensibilidade Microbiana , Mutação , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Streptococcus mutans/classificação
19.
Arch Microbiol ; 203(7): 4539-4548, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34152425

RESUMO

Difficulties in controlling the soil-borne plant pathogenic fungus Sclerotium rolfsii favoured the analysis of its suppressive soil for better understanding. In the present study, culture-independent molecular technique was used to analyse the bacterial communities of suppressive soil and conducive soil. Hence, metagenomic DNAs from both kinds of soils were directly extracted and their sequence polymorphism was analysed by targeting hypervariable domains, V4 + V5, of the 16S rRNA gene. The results of 16S rRNA gene-driven bacterial community diversity analysis along with soil physicochemical and biological properties clearly discriminated S. rolfsii suppressive soil from conducive soil. The dominant phylogenetic group of suppressive soil is Actinobacteria followed by Proteobacteria. The other groups include Acidobacteria, Firmicutes and Cyanobacteria. In contrast, conducive soil had very few Actinobacterial sequences and was dominated by Gamma- and Betaproteobacteria. Based on the relative proportion of different bacterial communities, their diversity and species richness were observed more in suppressive soil than in conducive soil. The present study identifies the dominant bacterial community which shares S. rolfsii suppressiveness.


Assuntos
Bactérias , Biodiversidade , Microbiologia do Solo , Antibiose/fisiologia , Bactérias/classificação , Bactérias/genética , Basidiomycota/fisiologia , Filogenia , RNA Ribossômico 16S/genética , Solo/química
20.
Sci Rep ; 11(1): 12001, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099817

RESUMO

Staphylococcus epidermidis (S. epidermidis) ATCC 12228 was incubated with 2% polyethylene glycol (PEG)-8 Laurate to yield electricity which was measured by a voltage difference between electrodes. Production of electron was validated by a Ferrozine assay. The anti-Cutibacterium acnes (C. acnes) activity of electrogenic S. epidermidis was assessed in vitro and in vivo. The voltage change (~ 4.4 mV) reached a peak 60 min after pipetting S. epidermidis plus 2% PEG-8 Laurate onto anodes. The electricity produced by S. epidermidis caused significant growth attenuation and cell lysis of C. acnes. Intradermal injection of C. acnes and S. epidermidis plus PEG-8 Laurate into the mouse ear considerably suppressed the growth of C. acnes. This suppressive effect was noticeably reversed when cyclophilin A of S. epidermidis was inhibited, indicating the essential role of cyclophilin A in electricity production of S. epidermidis against C. acnes. In summary, we demonstrate for the first time that skin S. epidermidis, in the presence of PEG-8 Laurate, can mediate cyclophilin A to elicit an electrical current that has anti-C. acnes effects. Electricity generated by S. epidermidis may confer immediate innate immunity in acne lesions to rein in the overgrowth of C. acnes at the onset of acne vulgaris.


Assuntos
Acne Vulgar/terapia , Antibiose/genética , Proteínas de Bactérias/genética , Ciclofilina A/genética , Propionibacteriaceae/patogenicidade , Staphylococcus epidermidis/efeitos dos fármacos , Acne Vulgar/microbiologia , Animais , Proteínas de Bactérias/metabolismo , Técnicas de Cocultura , Meios de Cultura/química , Meios de Cultura/farmacologia , Ciclofilina A/metabolismo , Modelos Animais de Doenças , Orelha/microbiologia , Eletricidade , Eletrodos , Feminino , Expressão Gênica , Lauratos/farmacologia , Camundongos , Camundongos Endogâmicos ICR , Polietilenoglicóis/farmacologia , Propionibacteriaceae/crescimento & desenvolvimento , Pele/microbiologia , Staphylococcus epidermidis/fisiologia , Tensoativos/farmacologia
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