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1.
Food Res Int ; 189: 114544, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876605

RESUMO

Previous studies have demonstrated that Staphylococcus cohnii WX_M8 and S. saprophyticus MY_A10 significantly enhanced the flavor of Chinese bacon in a mixed fermentation. However, due to the complexity of the processing, the contribution of the bacteria is deceptive when investigating only the phenotypic changes at the time of fermentation. In order to clarify the metabolic mechanisms of mixed fermentation, a technological characterization, whole genome and comparative genomics analysis, and metabolites were approached in this study. Results showed that differences in tolerance characteristics existed between WX_M8 and MY_A10. And the genomes of both the two strains consisted of one chromosome and four circular plasmids. Their genome sizes were 2.74 Mp and 2.62 Mp, the GC contents were 32.45% and 33.18%, and the predicted coding genes (CDS) were 2564 and 2541, respectively. Based on the annotation of gene functions and assessment of metabolic pathways in the KEGG database, WX_M8 and MY_A10 strains were found to harbor complete protein degradation and amino acid metabolic pathways, pyruvate and butanol metabolic pathways, and isoleucine metabolic pathways, and their diverse enzyme-encoding genes superimposed the metabolic functions, whereas the alcohol dehydrogenase genes, adh and frmA, achieved complementary functions in the production of esters. Comparative genomics analysis revealed a diversity of encoding genes of aminotransferases and a greater metabolism for sulfur-containing amino acids, aromatic amino acids, and branched-chain amino acids in the mixed fermentation of strains WX_M8 and MY_A10. Metabolites analysis showed that MY_A10 focused on the production of soluble peptides and free amino acids (FAAs), while WX_M8 focused on volatile organic compounds (VOCs), resulting in a significant enhancement of the flavor of Chinese bacon when the two were mixed fermented. This result may provide direction for strains WX_M8 and MY_A10 to be used as starter cultures and targeted to regulate flavor.


Assuntos
Fermentação , Genoma Bacteriano , Genômica , Staphylococcus , Staphylococcus/genética , Staphylococcus/metabolismo , Microbiologia de Alimentos , Staphylococcus saprophyticus/genética , Staphylococcus saprophyticus/metabolismo , Redes e Vias Metabólicas/genética , Produtos da Carne/microbiologia
2.
Int J Biol Macromol ; 272(Pt 1): 132860, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38834117

RESUMO

To explore the adjuvant therapy drugs of low-dose metformin, one homogeneous polysaccharide named APS-D1 was purified from Astragalus membranaceus by DEAE-52 cellulose and Sephadex G-100 column chromatography. Its chemical structure was characterized by molecular weight distribution, monosaccharide composition, infrared spectrum, methylation analysis, and NMR. The results revealed that APS-D1 (7.36 kDa) consisted of glucose, galactose, and arabinose (97.51 %:1.56 %:0.93 %). It consisted of →4)-α-D-Glcp-(1→ residue backbone with →3)-ß-D-Galp-(1→ residue and terminal-α/ß-D-Glcp-(1→ side chains. APS-D1 could significantly improve inflammation (TNF-α, LPS, and IL-10) in vivo. Moreover, APS-D1 improved the curative effect of low-dose metformin without adverse events. APS-D1 combined with low-dose metformin regulated several gut bacteria, in which APS-D1 enriched Staphylococcus lentus to produce l-carnitine (one of 136 metabolites of S. lentus). S. lentus and l-carnitine could improve diabetes, and reduction of S. lentusl-carnitine production impaired diabetes improvement. The combination, S. lentus, and l-carnitine could promote fatty acid oxidation (CPT1) and inhibit gluconeogenesis (PCK and G6Pase). The results indicated that APS-D1 enhanced the curative effect of low-dose metformin to improve diabetes by enriching S. lentus, in which the effect of S. lentus was mediated by l-carnitine. Collectively, these findings support that low-dose metformin supplemented with APS-D1 may be a favorable therapeutic strategy for type 2 diabetes.


Assuntos
Metformina , Polissacarídeos , Staphylococcus , Metformina/farmacologia , Metformina/química , Animais , Polissacarídeos/farmacologia , Polissacarídeos/química , Staphylococcus/efeitos dos fármacos , Camundongos , Astrágalo/química , Masculino , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Peso Molecular
3.
BMC Genomics ; 25(1): 575, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849728

RESUMO

BACKGROUND: Staphylococcus shinii appears as an umbrella species encompassing several strains of Staphylococcus pseudoxylosus and Staphylococcus xylosus. Given its phylogenetic closeness to S. xylosus, S. shinii can be found in similar ecological niches, including the microbiota of fermented meats where the species may contribute to colour and flavour development. In addition to these conventional functionalities, a biopreservation potential based on the production of antagonistic compounds may be available. Such potential, however, remains largely unexplored in contrast to the large body of research that is available on the biopreservative properties of lactic acid bacteria. The present study outlines the exploration of the genetic basis of competitiveness and antimicrobial activity of a fermented meat isolate, S. shinii IMDO-S216. To this end, its genome was sequenced, de novo assembled, and annotated. RESULTS: The genome contained a single circular chromosome and eight plasmid replicons. Focus of the genomic exploration was on secondary metabolite biosynthetic gene clusters coding for ribosomally synthesized and posttranslationally modified peptides. One complete cluster was coding for a bacteriocin, namely lactococcin 972; the genes coding for the pre-bacteriocin, the ATP-binding cassette transporter, and the immunity protein were also identified. Five other complete clusters were identified, possibly functioning as competitiveness factors. These clusters were found to be involved in various responses such as membrane fluidity, iron intake from the medium, a quorum sensing system, and decreased sensitivity to antimicrobial peptides and competing microorganisms. The presence of these clusters was equally studied among a selection of multiple Staphylococcus species to assess their prevalence in closely-related organisms. CONCLUSIONS: Such factors possibly translate in an improved adaptation and competitiveness of S. shinii IMDO-S216 which are, in turn, likely to improve its fitness in a fermented meat matrix.


Assuntos
Bacteriocinas , Genoma Bacteriano , Staphylococcus , Staphylococcus/genética , Staphylococcus/metabolismo , Bacteriocinas/genética , Bacteriocinas/metabolismo , Fermentação , Genômica/métodos , Metabolismo Secundário/genética , Carne/microbiologia , Família Multigênica , Filogenia
4.
BMC Pregnancy Childbirth ; 24(1): 412, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849751

RESUMO

BACKGROUND: Human breast milk (HBM) is a contributing factor in modulating the infant's gut microbiota, as it contains bacteria that are directly transferred to the infant during breastfeeding. It has been shown that children of women diagnosed with gestational diabetes mellitus (GDM) have a different gut microbiota compared to children of women without GDM. Our hypothesis is therefore that women with GDM have a different HBM microbiota, which may influence the metabolic function and capacity of the child later in life. The aim of this study was to investigate whether women with GDM have a different breast milk microbiota 1-3 weeks postpartum compared to women without GDM. METHODS: In this case-control study, a total of 45 women were included: 18 women with GDM and 27 women without GDM. A milk sample was collected from each participant 1 to 3 weeks postpartum and the bacterial composition was examined by 16 S rRNA gene sequencing targeting the V4 region. RESULTS: High relative abundances of Streptococcus and Staphylococcus were present in samples from both women with and without GDM. No difference could be seen in either alpha diversity, beta diversity, or specific taxa between groups. CONCLUSION: Our results did not support the existence of a GDM-associated breast milk microbiota at 1-3 weeks postpartum. Further research is needed to fully understand the development of the gut microbiota of infants born to mothers with GDM.


Assuntos
Diabetes Gestacional , Microbioma Gastrointestinal , Leite Humano , Humanos , Feminino , Leite Humano/microbiologia , Diabetes Gestacional/microbiologia , Gravidez , Adulto , Estudos de Casos e Controles , RNA Ribossômico 16S/análise , Período Pós-Parto , Microbiota , Streptococcus/isolamento & purificação , Aleitamento Materno , Staphylococcus/isolamento & purificação
5.
Front Cell Infect Microbiol ; 14: 1380289, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38868298

RESUMO

The antibiotic resistance (ABR) crisis is an urgent global health priority. Staphylococci are among the problematic bacteria contributing to this emergency owing to their recalcitrance to many clinically important antibiotics. Staphylococcal pathogenesis is further complicated by the presence of small colony variants (SCVs), a bacterial subpopulation displaying atypical characteristics including retarded growth, prolific biofilm formation, heightened antibiotic tolerance, and enhanced intracellular persistence. These capabilities severely impede current chemotherapeutics, resulting in chronic infections, poor patient outcomes, and significant economic burden. Tackling ABR requires alternative measures beyond the conventional options that have dominated treatment regimens over the past 8 decades. Non-antibiotic therapies are gaining interest in this arena, including the use of honey, which despite having ancient therapeutic roots has now been reimagined as an alternative treatment beyond just traditional topical use, to include the treatment of an array of difficult-to-treat staphylococcal infections. This literature review focused on Manuka honey (MH) and its efficacy as an anti-staphylococcal treatment. We summarized the studies that have used this product and the technologies employed to study the antibacterial mechanisms that render MH a suitable agent for the management of problematic staphylococcal infections, including those involving staphylococcal SCVs. We also discussed the status of staphylococcal resistance development to MH and other factors that may impact its efficacy as an alternative therapy to help combat ABR.


Assuntos
Antibacterianos , Mel , Infecções Estafilocócicas , Staphylococcus , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus/efeitos dos fármacos , Humanos , Antibacterianos/farmacologia , Fenótipo , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Animais , Leptospermum/química , Testes de Sensibilidade Microbiana
6.
Front Cell Infect Microbiol ; 14: 1404960, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38803574

RESUMO

Staphylococcus aureus and Staphylococcus epidermidis stand as notorious threats to human beings owing to the myriad of infections they cause. The bacteria readily form biofilms that help in withstanding the effects of antibiotics and the immune system. Intending to combat the biofilm formation and reduce the virulence of the pathogens, we investigated the effects of carotenoids, crocetin, and crocin, on four Staphylococcal strains. Crocetin was found to be the most effective as it diminished the biofilm formation of S. aureus ATCC 6538 significantly at 50 µg/mL without exhibiting bactericidal effect (MIC >800 µg/mL) and also inhibited the formation of biofilm by MSSA 25923 and S. epidermidis at a concentration as low as 2 µg/mL, and that by methicillin-resistant S. aureus MW2 at 100 µg/mL. It displayed minimal to no antibiofilm efficacy on the Gram-negative strains Escherichia coli O157:H7 and Pseudomonas aeruginosa as well as a fungal strain of Candida albicans. It could also curb the formation of fibrils, which partly contributes to the biofilm formation in S. epidermidis. Additionally, the ADME analysis of crocetin proclaims how relatively non-toxic the chemical is. Also, crocetin displayed synergistic antibiofilm characteristics in combination with tobramycin. The presence of a polyene chain with carboxylic acid groups at its ends is hypothesized to contribute to the strong antibiofilm characteristics of crocetin. These findings suggest that using apocarotenoids, particularly crocetin might help curb the biofilm formation by S. aureus and S. epidermidis.


Assuntos
Antibacterianos , Biofilmes , Carotenoides , Testes de Sensibilidade Microbiana , Staphylococcus epidermidis , Vitamina A , Biofilmes/efeitos dos fármacos , Carotenoides/farmacologia , Vitamina A/análogos & derivados , Vitamina A/farmacologia , Antibacterianos/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos
7.
J Biosci ; 492024.
Artigo em Inglês | MEDLINE | ID: mdl-38817159

RESUMO

Milk is a source of essential nutrients, but food safety across the milk supply chain has emerged as an integral part of food trade. Of the several food safety hazards, antimicrobial-resistant Staphylococcus species have emerged as one of the major microbial hazards with significant public health concerns. The present crosssectional study was undertaken with the objective to isolate Staphylococcus species from the milk supply chain, characterize isolates for antimicrobial resistance, and trace the origin of isolates using molecular techniques. Samples collected from the formal and informal milk supply chains showed prevalence of Staphylococcus species of 4.3% (n=720); isolates were identified as coagulase-positive (S. aureus 67.7% and S. intermedius 6.4%) and coagulase-negative (S. lentus 9.6%, S. sciuri 3.2%, S. xylosus 3.2%, S. schleiferi 3.2%, S. felis 3.2%, and S. gallinarum 3.2%) species. Staphylococcus isolates showed antimicrobial resistance to methicillin (32.2%), ß-lactam (41.9%), and macrolide-lincosamide-streptogramin B (3.2%). Staphylococcus isolates phenotypically resistant to methicillin also carried the mecA gene and displayed diverse pulsed field gel electrophoresis (PFGE) profiles, indicating their diverse origins in the milk supply chain. Based on the similarity of PFGE profile, the origin of one of the Staphylococcus isolates was traced to the soil in contact with milch cows. The findings of this study highlight the need for more comprehensive microbial risk analysis studies across the milk supply chain, capacity building, creation of awareness among stakeholders about the judicious use of antimicrobials, and protection of public health using a One-Health approach.


Assuntos
Antibacterianos , Leite , Staphylococcus , Leite/microbiologia , Animais , Staphylococcus/efeitos dos fármacos , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Microbiologia de Alimentos , Humanos , Bovinos , Proteínas de Bactérias/genética , Coagulase/genética , Coagulase/metabolismo , Farmacorresistência Bacteriana/genética
8.
Acta Vet Scand ; 66(1): 20, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769566

RESUMO

Bacteriophage-encoded endolysins, peptidoglycan hydrolases breaking down the Gram-positive bacterial cell wall, represent a groundbreaking class of novel antimicrobials to revolutionize the veterinary medicine field. Wild-type endolysins exhibit a modular structure, consisting of enzymatically active and cell wall-binding domains, that enable genetic engineering strategies for the creation of chimeric fusion proteins or so-called 'engineered endolysins'. This biotechnological approach has yielded variants with modified lytic spectrums, introducing new possibilities in antimicrobial development. However, the discovery of highly similar endolysins by different groups has occasionally resulted in the assignment of different names that complicate a straightforward comparison. The aim of this review was to perform a homology-based comparison of the wild-type and engineered endolysins that have been characterized in the context of bovine mastitis-causing streptococci and staphylococci, grouping homologous endolysins with ≥ 95.0% protein sequence similarity. Literature is explored by homologous groups for the wild-type endolysins, followed by a chronological examination of engineered endolysins according to their year of publication. This review concludes that the wild-type endolysins encountered persistent challenges in raw milk and in vivo settings, causing a notable shift in the field towards the engineering of endolysins. Lead candidates that display robust lytic activity are nowadays selected from screening assays that are performed under these challenging conditions, often utilizing advanced high-throughput protein engineering methods. Overall, these recent advancements suggest that endolysins will integrate into the antibiotic arsenal over the next decade, thereby innovating antimicrobial treatment against bovine mastitis-causing streptococci and staphylococci.


Assuntos
Bacteriófagos , Endopeptidases , Mastite Bovina , Staphylococcus , Animais , Mastite Bovina/microbiologia , Mastite Bovina/tratamento farmacológico , Bovinos , Endopeptidases/farmacologia , Endopeptidases/metabolismo , Endopeptidases/química , Endopeptidases/genética , Staphylococcus/efeitos dos fármacos , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/tratamento farmacológico , Streptococcus/efeitos dos fármacos , Feminino , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/tratamento farmacológico , Antibacterianos/farmacologia
9.
Int J Food Microbiol ; 418: 110726, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38704995

RESUMO

Pet food have been considered as possible vehicles of bacterial pathogens. The sudden boom of the pet food industry due to the worldwide increase in companion animal ownership calls for pet food investigations. Herein, this study aimed to determine the frequency, antimicrobial susceptibility profile, and molecular characteristics of coagulase-negative staphylococci (CoNS) in different pet food brands in Brazil. Eighty-six pet food packages were screened for CoNS. All isolates were identified at species level by MALDI-TOF MS and species-specific PCR. Antimicrobial susceptibility testing was performed by disc diffusion and broth microdilution (vancomycin and teicoplanin only) methods. The D-test was used to screen for inducible clindamycin phenotype (MLS-B). SCCmec typing and detection of mecA, vanA, vanB, and virulence-encoding genes were done by PCR. A total of 16 (18.6 %) CoNS isolates were recovered from pet food samples. Isolates were generally multidrug-resistant (MDR). All isolates were completely resistant (100 %) to penicillin. Resistances (12.5 % - 75 %) were also observed for fluoroquinolones, sulfamethoxazole-trimethoprim, tetracycline, rifampicin, erythromycin, and tobramycin. Isolates were susceptible to vancomycin (MICs <0.25-1 µg/mL) and teicoplanin (MICs <0.25-4 µg/mL). Intriguingly, 3/8 (37.5 %) CoNS isolates with the ERYRCLIS antibiotype expressed MLS-B phenotype. All isolates harboured blaZ gene. Seven (43.8 %) isolates carried mecA; and among them, the SCCmec Type III was the most frequent (n = 5/7; 71.4 %). Isolates also harboured seb, see, seg, sej, sem, etb, tsst, pvl, and hla toxin virulence-encoding genes (6.3 % - 25 %). A total of 12/16 (75 %) isolates were biofilm producers, while the icaAB gene was detected in an S. pasteuri isolate. Herein, it is shown that pet food is a potential source of clinically important Gram-positive bacterial pathogens. To the best of our knowledge, this is the first report of MLS-B phenotype and MR-CoNS in pet food in Latin America.


Assuntos
Antibacterianos , Clindamicina , Coagulase , Testes de Sensibilidade Microbiana , Staphylococcus , Staphylococcus/efeitos dos fármacos , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Brasil , Antibacterianos/farmacologia , Coagulase/metabolismo , Animais , Clindamicina/farmacologia , Meticilina/farmacologia , Ração Animal/microbiologia , Microbiologia de Alimentos , Animais de Estimação/microbiologia , Farmacorresistência Bacteriana Múltipla/genética
10.
Int J Food Microbiol ; 418: 110740, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38754174

RESUMO

Antimicrobial resistance (AMR) poses a significant challenge to global health, and the presence of antibiotic resistance genes (ARGs) in food poses a potential threat to public health. Traditional Chinese fermented meat products (FMPs) are highly favored because of their unique flavors and cultural value. However, microbial safety and the potential distribution and composition of AMR in these products remain unclear. In this study, a comprehensive analysis of bacterial composition and antibiotic-resistant populations in 216 samples of traditional fermented meat products from different regions of China was conducted using a metagenomic approach. Staphylococcus was the most abundant genus in the samples, accounting for an average abundance of 29.9 %, followed by Tetragenococcus (17.1 %), and Latilactobacillus (3.6 %). A core resistome of FMP samples was constructed for the first time using co-occurrence network analysis, which revealed the distribution and interrelationships of ARGs and bio/metal-resistant genes (BMRGs). Random forest analysis identified the lincosamide nucleotidyltransferase lnuA and the multidrug and toxic compound extrusion (MATE) transporter abeM as potential indicators for assessing the overall abundance of the core resistome. Additionally, Staphylococcus, Acinetobacter, and Pseudomonas were identified as hosts constituting the core resistome. Despite their low abundance, the latter two still serve as major reservoirs of antibiotic resistance genes. Notably, Lactococcus cremoris was identified as the key host for tetracycline resistance genes in the samples, highlighting the need for enhanced resistance monitoring in lactic acid bacteria. Based on our findings, in the microbial safety assessment of fermented meat products, beyond common foodborne pathogens, attention should be focused on detecting and controlling coagulase-negative Staphylococcus, Acinetobacter, and Pseudomonas, and addressing bacterial resistance. The quantitative detection of lnuA and abeM could provide a convenient and rapid method for assessing the overall abundance of the core resistome. Our findings have important implications for the control of bacterial resistance and prevention of pathogenic bacteria in fermented meat products.


Assuntos
Antibacterianos , Bactérias , Farmacorresistência Bacteriana , Alimentos Fermentados , Microbiologia de Alimentos , Produtos da Carne , Metagenômica , Produtos da Carne/microbiologia , China , Bactérias/genética , Bactérias/efeitos dos fármacos , Bactérias/classificação , Bactérias/isolamento & purificação , Farmacorresistência Bacteriana/genética , Alimentos Fermentados/microbiologia , Antibacterianos/farmacologia , Fermentação , Metagenoma , Staphylococcus/genética , Staphylococcus/efeitos dos fármacos , Staphylococcus/isolamento & purificação , População do Leste Asiático
11.
Chemosphere ; 359: 142169, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38710416

RESUMO

With the increasing production and use of polyurethanes (PUs), it is necessary to develop sustainable techniques for the remediation of plastic pollution. The use of microorganisms capable of biodegrading PUs may be an environmentally desirable solution for controlling these plastic contaminants. To contribute to the discovery of alternatives for the mitigation of plastics in the environment, this study aimed to explore the potential of StaphylococcuswarneriUFV_01.21, isolated from the gut of Galleria mellonellalarvae, for biodegradation of PU in pure culture and microbial co-culture with Serratia liquefaciensL135. S. warneri grew using Impranil® PU as the sole carbon source in pure culture and co-culture. With six days of incubation, the biodegradation of Impranil® in Luria Bertani broth was 96, 88 and 76%, while in minimal medium, it was 58, 54 and 42% for S. warneri, S. liquefaciens, and co-culture, respectively. In addition, S. warneri in pure culture or co-culture was able to biodegrade, adhere and form biofilms on the surfaces of Impranil® disks and poly[4,4'-methylenebis (phenyl isocyanate)-alt-1,4-butanediol/di(propylene glycol)/polycaprolactone] (PCLMDI) films. Scanning electron microscopy also revealed biodegradation by detecting the formation of cracks, furrows, pores, and roughness on the surfaces of inoculated PU, both with pure culture and microbial co-culture. This study is the first to demonstrate the potential of S. warneriin PU biodegradation.


Assuntos
Biodegradação Ambiental , Técnicas de Cocultura , Poliuretanos , Staphylococcus , Poliuretanos/metabolismo , Staphylococcus/metabolismo , Biofilmes , Plásticos/metabolismo , Serratia liquefaciens/metabolismo
12.
J Biosci ; 492024.
Artigo em Inglês | MEDLINE | ID: mdl-38726825

RESUMO

Bacterial species referred to as magnetotactic bacteria (MTB) biomineralize iron oxides and iron sulphides inside the cell. Bacteria can arrange themselves passively along geomagnetic field lines with the aid of these iron components known as magnetosomes. In this study, magnetosome nanoparticles, which were obtained from the taxonomically identified MTB isolate Providencia sp. PRB-1, were characterized and their antibacterial activity was evaluated. An in vitro test showed that magnetosome nanoparticles significantly inhibited the growth of Staphylococcus sp., Pseudomonas aeruginosa, and Klebsiella pneumoniae. Magnetosomes were found to contain cuboidal iron crystals with an average size of 42 nm measured by particle size analysis and scanning electron microscope analysis. The energy dispersive X-ray examination revealed that Fe and O were present in the extracted magnetosomes. The extracted magnetosome nanoparticles displayed maximum absorption at 260 nm in the UV-Vis spectrum. The distinct magnetite peak in the Fourier transform infrared (FTIR) spectroscopy spectra was observed at 574.75 cm-1. More research is needed into the intriguing prospect of biogenic magnetosome nanoparticles for antibacterial applications.


Assuntos
Antibacterianos , Magnetossomos , Nanopartículas , Providencia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Ferro/química , Ferro/metabolismo , Klebsiella pneumoniae/efeitos dos fármacos , Nanopartículas de Magnetita/química , Magnetossomos/química , Magnetossomos/metabolismo , Testes de Sensibilidade Microbiana , Nanopartículas/química , Tamanho da Partícula , Providencia/química , Pseudomonas aeruginosa/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus/efeitos dos fármacos
13.
Microb Genom ; 10(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38739120

RESUMO

Cutaneous ulcers are common in yaws-endemic areas. Although often attributed to 'Treponema pallidum subsp. pertenue' and Haemophilus ducreyi, quantitative PCR has highlighted a significant proportion of these ulcers are negative for both pathogens and are considered idiopathic. This is a retrospective analysis utilising existing 16S rRNA sequencing data from two independent yaws studies that took place in Ghana and the Solomon Islands. We characterized bacterial diversity in 38 samples to identify potential causative agents for idiopathic cutaneous ulcers. We identified a diverse bacterial profile, including Arcanobacterium haemolyticum, Campylobacter concisus, Corynebacterium diphtheriae, Staphylococcus spp. and Streptococcus pyogenes, consistent with findings from previous cutaneous ulcer microbiome studies. No single bacterial species was universally present across all samples. The most prevalent bacterium, Campylobacter ureolyticus, appeared in 42% of samples, suggesting a multifactorial aetiology for cutaneous ulcers in yaws-endemic areas. This study emphasizes the need for a nuanced understanding of potential causative agents. The findings prompt further exploration into the intricate microbial interactions contributing to idiopathic yaw-like ulcers, guiding future research toward comprehensive diagnostic and therapeutic strategies.


Assuntos
Microbiota , RNA Ribossômico 16S , Úlcera Cutânea , Humanos , RNA Ribossômico 16S/genética , Úlcera Cutânea/microbiologia , Gana , Masculino , Bouba/microbiologia , Bouba/diagnóstico , Estudos Retrospectivos , Feminino , Adulto , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Melanesia , Pessoa de Meia-Idade , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Staphylococcus/classificação , Streptococcus pyogenes/genética , Streptococcus pyogenes/isolamento & purificação , Streptococcus pyogenes/classificação , Arcanobacterium/genética , Arcanobacterium/isolamento & purificação , Campylobacter/genética , Campylobacter/isolamento & purificação , Campylobacter/classificação
14.
J Appl Microbiol ; 135(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38772746

RESUMO

AIMS: We developed three new analogs of the antimicrobial peptide (AMP) Citropin 1.1: DAN-1-13, AJP-1-1, and HHX-2-28, and tested their potential antimicrobial and antibiofilm activities against Staphylococcus aureus and S. pseudintermedius. Potential cytotoxic or hemolytic effects were determined using cultured human keratinocytes and erythrocytes to determine their safety. METHODS AND RESULTS: To assess the antimicrobial activity of each compound, minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined against methicillin-resistant and methicillin-susceptible strains of S. aureus and S. pseudintermedius. Activity against newly formed and mature biofilms was determined in two clinical isolates using spectrophotometry and scanning electron microscopy (SEM). All three compounds exhibited antimicrobial and bactericidal activity against all studied S. aureus and S. pseudintermedius strains, with MICs ranging from 4-32 µg ml-1 and MBCs ranging from 8-128 µg ml-1. Subinhibitory concentrations of all compounds also showed ant-biofilm activity in the two tested isolates. All compounds exhibited limited cytotoxic and hemolytic activity. CONCLUSIONS: Novel analogs of Citropin 1.1 exhibit antimicrobial and bactericidal activities against S. aureus and S. pseudintermedius isolates and inhibit the biofilm formation of these bacteria.


Assuntos
Antibacterianos , Biofilmes , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Staphylococcus , Biofilmes/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Humanos , Antibacterianos/farmacologia , Staphylococcus/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Eritrócitos/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos
15.
Vet J ; 305: 106153, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821205

RESUMO

Staphylococcus spp. are growing pathogens in humans and companion animals. The emergence of multidrug-resistant bacterial infections, such as methicillin-resistant Staphylococcus-associated infections, due to zoonotic transmission, is a major public health concern. Domestic animals, such as dogs and cats, are possible reservoirs of multi-resistant bacterial species, which makes it relevant to monitor them due to their proximity to humans. However, there is a lack of information on the real scenario in Europe, especially in Portugal, particularly for animal infections caused by Staphylococcus spp. Therefore, this study aimed to investigate the antimicrobial resistance profile of Staphylococcus spp. isolated from cats and dogs diagnosed with infection in Northern Portugal. During 2021-2023, 96 Staphylococcus isolates from dogs and cats with symptoms of bacterial infection, including animals being treated in veterinary clinics/hospitals and cadavers submitted for necropsy at INIAV were included in the study collection. Of the 96 isolates, 63 were from dogs and 33 were Staphylococcus spp. from cats, most of which were isolated from ear (57% and 18%, respectively), skin (19 % and 27 %, respectively) and respiratory tract infections (6 % and 27 %, respectively). Among all the isolates, 12 different Staphylococcus spp. were identified, with Staphylococcus pseudintermedius being the most identified (61 % from dogs and 30 % from cats). It is noteworthy that 36 % of the isolates were multi-drug resistant and 25 % of the isolates showed a methicillin-resistant phenotype, with the mecA gene having been identified in all these isolates. This study highlights a high occurrence of multidrug-resistant Staphylococcus spp. in companion animals in Northern Portugal. This underlines the potential for cats and dogs to act as reservoirs of antimicrobial resistance, that can be transmitted to humans, posing a serious threat to public health.


Assuntos
Antibacterianos , Doenças do Gato , Doenças do Cão , Animais de Estimação , Infecções Estafilocócicas , Staphylococcus , Animais , Gatos , Cães , Portugal/epidemiologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Doenças do Gato/microbiologia , Doenças do Gato/epidemiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Doenças do Cão/microbiologia , Doenças do Cão/epidemiologia , Antibacterianos/farmacologia , Animais de Estimação/microbiologia , Testes de Sensibilidade Microbiana/veterinária , Farmacorresistência Bacteriana Múltipla , Farmacorresistência Bacteriana
16.
Vet Microbiol ; 294: 110104, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38768556

RESUMO

The evolutionary lineage and taxonomy of the Australian dingo is controversial, however recent genomic and gut metagenomic research has suggested that dingoes are evolutionarily distinct from modern dogs. Staphylococcus species are known commensal organisms of dogs and other mammals. In this study we took the opportunity to determine the carriage rate and antimicrobial resistance profiles of Staphylococcus species from 15 captive Australian dingoes. S. pseudintermedius was the only coagulase-positive species recovered, isolated from 6/15 (40%) and 9/13 (69%) of the animals during the 2020 (winter) and 2021 (summer) sampling times, respectively. Twenty-three coagulase-negative isolates were characterised, with S. equorum being the most frequently (20/23, 87%) recovered species. Two isolates of S. equorum had their genomes sequenced to learn more about this species. Antimicrobial resistance amongst both coagulase-positive and -negative isolates was low; with resistance to only 3 of 12 antimicrobials observed: penicillin, erythromycin, and trimethoprim. We have shown that the Australian dingo is a host organism for S. pseudintermedius much like it is in dogs, however the carriage rate was lower than has previously been reported from dogs in Australia.


Assuntos
Antibacterianos , Portador Sadio , Infecções Estafilocócicas , Staphylococcus , Animais , Staphylococcus/efeitos dos fármacos , Staphylococcus/classificação , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Antibacterianos/farmacologia , Portador Sadio/microbiologia , Portador Sadio/veterinária , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Vitória/epidemiologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana , Cães/microbiologia , Canidae/microbiologia , Masculino , Feminino
17.
Res Vet Sci ; 174: 105305, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38805894

RESUMO

Staphylococcus pseudintermedius is one species in the commensal staphylococcal population in dogs. While it is commonly carried on healthy companion dogs it is also an opportunistic pathogen associated with a range of skin, ear, wound and other infections. While adapted to dogs, it is not restricted to them, and we have reviewed its host range, including increasing reports of human colonisation and infections. Despite its association with pet dogs, S. pseudintermedius is found widely in animals, covering companion, livestock and free-living species of birds and mammals. Human infections, typically in immunocompromised individuals, are increasingly being recognised, in part due to improved diagnosis. Colonisation, infection, and antimicrobial resistance, including frequent multidrug resistance, among S. pseudintermedius isolates represent important One Health challenges.


Assuntos
Doenças do Cão , Especificidade de Hospedeiro , Infecções Estafilocócicas , Staphylococcus , Animais , Humanos , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Cães/microbiologia , Doenças do Cão/microbiologia , Zoonoses/microbiologia , Zoonoses Bacterianas/microbiologia
18.
Vet Microbiol ; 294: 110133, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820726

RESUMO

Non-aureus staphylococci (NAS) are an essential group of bacteria causing antimicrobial resistant intramammary infections in livestock, particularly dairy cows. Therefore, bacteriophages emerge as a potent bactericidal agent for NAS mastitis. This study aimed to obtain NAS-specific bacteriophages using bacterial strains isolated from cows with mastitis, subsequently evaluating their morphological, genomic, and lytic characteristics. Four distinct NAS bacteriophages were recovered from sewage or the environment of Chinese dairy farms; PT1-1, PT94, and PT1-9 were isolated using Staphylococcus chromogenes and PT1-4 using Staphylococcus gallinarum. Both PT1-1 (24/54, 44 %) and PT94 (28/54, 52 %) had broader lysis than PT1-4 (3/54, 6 %) and PT1-9 (10/54, 19 %), but PT1-4 and PT1-9 achieved cross-species lysis. All bacteriophages had a short latency period and good environmental tolerance, including surviving at pH=4-10 and at 30-60℃. Except for PT1-9, all bacteriophages had excellent bactericidal efficacy within 5 h of co-culture with host bacteria in vitro at various multiplicity of infection (MOIs). Based on whole genome sequencing, average nucleotide identity (ANI) analysis of PT1-1 and PT94 can be classified as the same species, consistent with whole-genome synteny analysis. Although motifs shared by the 4 bacteriophages differed little from those of other bacteriophages, a phylogenetic tree based on functional proteins indicated their novelty. Moreover, based on whole genome comparisons, we inferred that cross-species lysis of bacteriophage may be related to the presence of "phage tail fiber." In conclusion 4 novel NAS bacteriophages were isolated; they had good biological properties and unique genomes, with potential for NAS mastitis therapy.


Assuntos
Genoma Viral , Mastite Bovina , Esgotos , Staphylococcus , Esgotos/virologia , Esgotos/microbiologia , Animais , Staphylococcus/virologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/genética , Bovinos , Feminino , Mastite Bovina/microbiologia , Fagos de Staphylococcus/genética , Fagos de Staphylococcus/fisiologia , Fagos de Staphylococcus/classificação , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Bacteriófagos/classificação , Bacteriófagos/fisiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Filogenia , Genômica , Sequenciamento Completo do Genoma
19.
FEMS Microbiol Ecol ; 100(6)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38806244

RESUMO

Coagulase-negative Staphylococcus (CoNS) species inhibiting Staphylococcus aureus has been described in the skin of atopic dermatitis (AD) patients. This study evaluated whether Staphylococcus spp. from the skin and nares of AD and non-AD children produced antimicrobial substances (AMS). AMS production was screened by an overlay method and tested against NaOH, proteases and 30 indicator strains. Clonality was assessed by pulsed-field gel electrophoresis. Proteinaceous AMS-producers were investigated for autoimmunity by the overlay method and presence of bacteriocin genes by polymerase chain reaction. Two AMS-producers had their genome screened for AMS genes. A methicillin-resistant S. aureus (MRSA) produced proteinaceous AMS that inhibited 51.7% of the staphylococcal indicator strains, and it was active against 60% of the colonies selected from the AD child where it was isolated. On the other hand, 57 (8.8%) CoNS from the nares and skin of AD and non-AD children, most of them S. epidermidis (45.6%), reduced the growth of S. aureus and other CoNS species. Bacteriocin-related genes were detected in the genomes of AMS-producers. AMS production by CoNS inhibited S. aureus and other skin microbiota species from children with AD. Furthermore, an MRSA colonizing a child with AD produced AMS, reinforcing its contribution to dysbiosis and disease severity.


Assuntos
Coagulase , Dermatite Atópica , Staphylococcus aureus Resistente à Meticilina , Microbiota , Pele , Staphylococcus , Dermatite Atópica/microbiologia , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Pele/microbiologia , Criança , Coagulase/genética , Coagulase/metabolismo , Staphylococcus/genética , Bacteriocinas/genética , Antibacterianos/farmacologia , Pré-Escolar , Testes de Sensibilidade Microbiana
20.
Anim Sci J ; 95(1): e13959, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38769761

RESUMO

This study investigates the relationships between subclinical mastitis and milk quality with selected microRNAs in cow milk. California Mastitis Test (CMT)-positive (n = 20) and negative (n = 20) samples were compared (Experiment I). Additionally, samples with CMT-positive but microbiological-negative, as well as positive for only Staphylococcus subspecies (Staph spp.) and only Streptococcus subspecies (Strep spp.) were examined (Experiment II). Four groups were formed in Experiment II: Group I (CMT and microbiological-negative) (n = 20), Group II (CMT-positive but microbiological-negative) (n = 10), Group III (Staph spp.) (n = 5), Group IV (Strep spp.) (n = 5). While electrical conductivity, somatic cell count (SCC), malondialdehyde (MDA) increased, miR-27a-3p and miR-223 upregulated and miR-125b downregulated in the CMT-positive group in Experiment I. SCC and MDA were higher in CMT-positive groups. miR-27a-3p and miR-223 upregulated in Groups III and IV. While miR-155 is upregulated, miR-125b downregulated in Group IV. Milk fat is positively correlated with miR-148a and miR-223. As miR-27a-3p positively correlated with SCC and MDA, miR-125b negatively correlated with electrical conductivity and SCC. miR-148a and MDA were positively correlated. miR-155 was correlated with fat-free dry matter, protein, lactose, and freezing point. miR-223 was positively correlated with SCC and miR-148a. Results particularly highlight miR-27a-3p and miR-223 as potential biomarkers in subclinical mastitis, especially those caused by Staph spp. and Strep spp., while miR-148a, miR-155, and miR-223 stand out in determining milk quality.


Assuntos
Mastite Bovina , MicroRNAs , Leite , Animais , Leite/microbiologia , MicroRNAs/metabolismo , MicroRNAs/genética , Bovinos , Feminino , Mastite Bovina/microbiologia , Mastite Bovina/diagnóstico , Mastite Bovina/genética , Mastite Bovina/metabolismo , Staphylococcus/isolamento & purificação , Contagem de Células/veterinária , Streptococcus/isolamento & purificação , Qualidade dos Alimentos , Malondialdeído/metabolismo , Malondialdeído/análise , Condutividade Elétrica , Infecções Assintomáticas
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