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1.
World J Microbiol Biotechnol ; 40(7): 202, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743315

RESUMO

Currently, heavy metal-resistant (HMR) marine actinomycetes have attracted much attention worldwide due to their unique capabilities. In this study, 27 marine-derived actinomycetes were isolated from coastal beaches in the Arabian Gulf of Al-Jubail in Saudi Arabia and screened for resistance to 100 mg/L of the heavy metals Cd2+, Cr6+, Cu2+, Fe2+, Pb2+, and Ni2+ using different assay techniques. Six isolates were selected as HMRs, of which two isolates, JJB5 and JJB11, exhibited the highest maximum tolerance concentrations (200- > 300 mg/L). Both isolates were the highest among six-HMR screened for their biodegradation potential of plastics low-density polyethylene, polystyrene, and polyvinyl chloride, recording the highest weight loss (15 ± 1.22 - 65 ± 1.2%) in their thin films. They also showed the highest biodegradability of the pesticides acetamiprid, chlordane, hexachlorocyclohexane, indoxacarb and lindane, indicating promising removal capacities (95.70-100%) for acetamiprid and indoxacarb using HPLC analysis. Additionally, the cell-free filtrate (CFF) of both isolates displayed the highest antimicrobial activity among the six-HMR screened against a variety of microbial test strains, recording the highest inhibition zone diameters (13.76 ± 0.66 - 26.0 ± 1.13 mm). GC‒MS analyses of the ethyl acetate extract of their CFFs revealed the presence of diverse chemical compounds with a multitude of remarkable biological activities. Based on their spore morphology and wall-chemotype, they were assigned to the nocardioform-actinomycetes. Furthermore, their phenotypic characteristics, together with 16S rRNA gene sequencing (OR121525-OR121526), revealed them as Nocardia harenae JJB5 and Amycolatopsis marina JJB11. Our results suggest that marine HMR actinomycetes are promising candidates for various biotechnological applications.


Assuntos
Biodegradação Ambiental , Metais Pesados , Testes de Sensibilidade Microbiana , Nocardia , RNA Ribossômico 16S , Metais Pesados/metabolismo , RNA Ribossômico 16S/genética , Nocardia/isolamento & purificação , Nocardia/genética , Nocardia/metabolismo , Arábia Saudita , Antibacterianos/farmacologia , Filogenia , Actinobacteria/metabolismo , Actinobacteria/isolamento & purificação , Actinobacteria/genética , Actinobacteria/classificação , Poluentes Químicos da Água/metabolismo , Água do Mar/microbiologia , Praguicidas/metabolismo , Farmacorresistência Bacteriana
2.
BMJ Case Rep ; 17(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749526

RESUMO

We report the case of a female patient in her late 20s who visited the clinic with concerns about poor vision, redness, watering and a burning sensation in her left eye 2 weeks after undergoing a small incision lenticule extraction. She had no history of systemic illness or immunosuppressed status. On slit lamp examination, she was found to have corneal stromal infiltrates in the interface at multiple locations. Given the clinical diagnosis of microbial keratitis, corneal scraping of the interface infiltrate was performed and sent for microbiological examination revealing gram-positive, thin, beaded filaments that were acid-fast positive and later identified by growth in culture media as Nocardia species. This case was managed successfully with the use of topical amikacin and systemic trimethoprim-sulfamethoxazole with complete resolution of infection.


Assuntos
Antibacterianos , Infecções Oculares Bacterianas , Ceratite , Nocardiose , Humanos , Feminino , Nocardiose/diagnóstico , Nocardiose/tratamento farmacológico , Ceratite/microbiologia , Ceratite/tratamento farmacológico , Ceratite/diagnóstico , Ceratite/cirurgia , Antibacterianos/uso terapêutico , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/microbiologia , Infecções Oculares Bacterianas/tratamento farmacológico , Amicacina/uso terapêutico , Amicacina/administração & dosagem , Adulto , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Nocardia/isolamento & purificação , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/diagnóstico
3.
J Ethnopharmacol ; 330: 118199, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38631486

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Nocardiosis is an uncommon infectious disease that bears certain similarities to tuberculosis, with a continuous increase in its incidence and a poor prognosis. In traditional Chinese medicine, the leaves of Cajanus cajan (L.) Millsp. are employed to treat wounds, malaria, coughs, and abdominal pain. AIM OF THE STUDY: In this study, we investigated the effects and mechanisms of longistylin A (LGA), a natural stilbene isolated from C. cajan, as a potential antibiotic against nocardiosis. MATERIALS AND METHODS: LGA was isolated from the leaves of C. cajan and assessed using a minimum bactericidal concentration (MBC) determination against Nocardia seriolae. Multi-omics analysis encompassing genes, proteins, and metabolites was conducted to investigate the impact of LGA treatment on N. seriolae. Additionally, quantitative analysis of 40 cytokinins in N. seriolae mycelium was performed to assess the specific effects of LGA treatment on cytokinin levels. Cryo-scanning electron microscopy was utilized to examine morphological changes induced by LGA treatment, particularly in the presence of exogenous trans-zeatin-O-glucoside (tZOG). The therapeutic effect of LGA was investigated by feeding N. seriolae-infected largemouth bass. RESULTS: LGA exhibited significant efficacy against N. seriolae, with MBC value of 2.56 µg/mL. Multi-omics analysis revealed that LGA disrupted glycerophospholipid metabolism and hormone biosynthesis by notably reducing the expression of glycerol-3-phosphate dehydrogenase and calmodulin-like protein. Treatment with LGA markedly disrupted 12 distinct cytokinins in N. seriolae mycelium. Additionally, the addition of exogenous tZOG counteracted the inhibitory effects of LGA on filamentous growth, resulting in mycelial elongation and branching. Furthermore, LGA treatment improved the survival rate of largemouth bass infected with N. seriolae. CONCLUSIONS: We found for the first time that LGA from C. cajan exhibited significant efficacy against N. seriolae by interfering with glycerophospholipid metabolism and cytokinin biosynthesis.


Assuntos
Antibacterianos , Cajanus , Citocininas , Glicerofosfolipídeos , Nocardia , Nocardia/metabolismo , Nocardia/efeitos dos fármacos , Citocininas/farmacologia , Citocininas/biossíntese , Citocininas/metabolismo , Glicerofosfolipídeos/metabolismo , Glicerofosfolipídeos/biossíntese , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Folhas de Planta
4.
Int J Biol Macromol ; 268(Pt 1): 131863, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38670188

RESUMO

The complement system is pivotal in innate immune defense, with Complement 1qb (C1qb) playing a key role in recognizing immune complexes and initiating the classical pathway. In this research, we cloned the full-length cDNA of silver pomfret (Pampus argenteus) c1qb and demonstrated its role in mediating defense responses against Nocardia seriolae (N. seriolae) infection, which notably causes significant economic losses in the aquaculture industry. Our investigation revealed that N. seriolae infection led to tissue damage in fish bodies, as observed in tissue sections. Subsequent analysis of differential genes (DEGs) in the transcriptome highlighted genes linked to apoptosis and inflammation. Through experiments involving overexpression and interference of c1qb in vitro, we confirmed that c1qb could suppress N. seriolae-induced apoptosis and inflammation. Moreover, overexpression of c1qb hindered N. seriolae invasion, and the purified and replicated C1qb protein displayed antimicrobial properties. Additionally, our study unveiled that overexpression of c1qb might stimulate the expression of membrane attack complexes (MAC), potentially enhancing opsonization and antibacterial effects. In conclusion, our findings offer valuable insights into the immune antibacterial mechanisms of c1qb and contribute to the development of strategies for controlling N. seriolae.


Assuntos
Apoptose , Complemento C1q , Complexo de Ataque à Membrana do Sistema Complemento , Inflamação , Nocardia , Complemento C1q/metabolismo , Complemento C1q/genética , Apoptose/genética , Animais , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Inflamação/genética , Inflamação/metabolismo , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Nocardiose/imunologia , Nocardiose/microbiologia , Nocardiose/metabolismo , Nocardiose/genética
5.
Fish Shellfish Immunol ; 149: 109531, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604479

RESUMO

In this study, we present the first cloning and identification of perforin (MsPRF1) in largemouth bass (Micropterus salmoides). The full-length cDNA of MsPRF1 spans 1572 base pairs, encoding a 58.88 kDa protein consisting of 523 amino acids. Notably, the protein contains MACPF and C2 structural domains. To evaluate the expression levels of MsPRF1 in various healthy largemouth bass tissues, real-time quantitative PCR was employed, revealing the highest expression in the liver and gut. After the largemouth bass were infected by Nocardia seriolae, the mRNA levels of MsPRF1 generally increased within 48 h. Remarkably, the recombinant protein MsPRF1 exhibits inhibitory effects against both Gram-negative and Gram-positive bacteria. Additionally, the largemouth bass showed a higher survival rate in the N. seriolae challenge following the intraperitoneal injection of rMsPRF1, with observed reductions in the tissue bacterial loads. Moreover, rMsPRF1 demonstrated a significant impact on the phagocytic and bactericidal activities of largemouth bass MO/MΦ cells, concurrently upregulating the expression of pro-inflammatory factors. These results demonstrate that MsPRF1 has a potential role in the immune response of largemouth bass against N. seriolae infection.


Assuntos
Sequência de Aminoácidos , Bass , Doenças dos Peixes , Proteínas de Peixes , Nocardia , Perforina , Filogenia , Animais , Bass/imunologia , Bass/genética , Doenças dos Peixes/imunologia , Perforina/genética , Perforina/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/química , Nocardia/imunologia , Nocardiose/veterinária , Nocardiose/imunologia , Regulação da Expressão Gênica/imunologia , Alinhamento de Sequência/veterinária , Imunidade Inata/genética , Perfilação da Expressão Gênica/veterinária , Sequência de Bases
6.
J Infect ; 88(6): 106162, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663756

RESUMO

OBJECTIVES: Nocardiosis is a rare but life-threatening infection after hematopoietic cell transplantation (HCT). We aimed at identifying risk factors for nocardiosis after allogeneic HCT and clarifying the effect of trimethoprim-sulfamethoxazole prophylaxis on its occurrence. METHODS: We performed a retrospective multicenter case-control study of patients diagnosed with nocardiosis after allogeneic HCT between January 2000 and December 2018. For each case, two controls were matched by center, transplant date, and age group. Multivariable analysis was conducted using conditional logistic regression to identify potential risk factors for nocardiosis. Kaplan-Meier survival curves of cases and controls were compared using log-rank tests. RESULTS: Sixty-four cases and 128 controls were included. Nocardiosis occurred at a median of 9 months after allogeneic HCT (interquartile range: 5-18). After adjustment for potential confounders in a multivariable model, Nocardia infection was associated with tacrolimus use (adjusted odds ratio [aOR] 9.9, 95 % confidence interval [95 % CI]: 1.6-62.7), lymphocyte count < 500/µL (aOR 8.9, 95 % CI: 2.3-34.7), male sex (aOR 8.1, 95 % CI: 2.1-31.5), recent use of systemic corticosteroids (aOR 7.9, 95 % CI: 2.2-28.2), and recent CMV infection (aOR 4.3, 95 % CI: 1.2-15.9). Conversely, use of trimethoprim-sulfamethoxazole prophylaxis was associated with a significantly decreased risk of nocardiosis (aOR 0.2, 95 % CI: 0.1-0.8). HCT recipients who developed nocardiosis had a significantly decreased survival, as compared with controls (12-month survival: 58 % and 90 %, respectively; p < 0.0001). CONCLUSIONS: We identified six factors independently associated with the occurrence of nocardiosis among allogeneic HCT recipients. In particular, trimethoprim-sulfamethoxazole prophylaxis was found to protect against nocardiosis.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Nocardiose , Combinação Trimetoprima e Sulfametoxazol , Humanos , Nocardiose/epidemiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Masculino , Feminino , Estudos de Casos e Controles , Fatores de Risco , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Transplante Homólogo/efeitos adversos , Idoso , Transplantados/estatística & dados numéricos , Nocardia/isolamento & purificação , Antibioticoprofilaxia
7.
BMC Infect Dis ; 24(1): 381, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589778

RESUMO

BACKGROUND: Nocardia farcinica is one of the most common Nocardia species causing human infections. It is an opportunistic pathogen that often infects people with compromised immune systems. It could invade human body through respiratory tract or skin wounds, cause local infection, and affect other organs via hematogenous dissemination. However, N. farcinica-caused bacteremia is uncommon. In this study, we report a case of bacteremia caused by N. farcinica in China. CASE PRESENTATION: An 80-year-old woman was admitted to Peking Union Medical College Hospital with recurrent fever, right abdominal pain for one and a half month, and right adrenal gland occupation. N. farcinica was identified as the causative pathogen using blood culture and plasma metagenomics next-generation sequencing (mNGS). The clinical considerations included bacteremia and adrenal gland abscess caused by Nocardia infection. As the patient was allergic to sulfanilamide, imipenem/cilastatin and linezolid were empirically administered. Unfortunately, the patient eventually died less than a month after the initiation of anti-infection treatment. CONCLUSION: N. farcinica bacteremia is rare and its clinical manifestations are not specific. Its diagnosis depends on etiological examination, which can be confirmed using techniques such as Sanger sequencing and mNGS. In this report, we have reviewed cases of Nocardia bloodstream infection reported in the past decade, hoping to improve clinicians' understanding of Nocardia bloodstream infection and help in its early diagnosis and timely treatment.


Assuntos
Bacteriemia , Nocardiose , Nocardia , Sepse , Feminino , Humanos , Idoso de 80 Anos ou mais , Nocardia/genética , Nocardiose/diagnóstico , Nocardiose/tratamento farmacológico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico
8.
Int J Mol Sci ; 25(6)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38542396

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder with an unknown cause. Recent research has highlighted the importance of the gut in neuronal and immune maturation through the exchange of nutrients and cellular signals. This has led to the "gut-first PD" hypothesis, which aims to explain many of the sporadic cases and their prodromal intestinal symptoms, such as constipation and intestinal α-synuclein (aSyn) aggregation. The link between mitochondrial dysfunction and aSyn deposition is central to PD pathophysiology, since they can also trigger pro-inflammatory signals associated with aSyn deposition, potentially contributing to the onset of PD. As mitochondria are derived from ancestral alpha-proteobacteria, other bacteria may specifically target this organelle. We sought to use Nocardia cyriacigeorgica, a bacterium previously associated with parkinsonism, and dextran sulfate sodium (DSS) as pro-inflammatory modulators to gain further insight into the onset of PD. This study indicates that aSyn aggregation plus mitochondrial dysfunction without intestinal barrier leakage are not sufficient to trigger gut-first PD.


Assuntos
Colite , Doenças Mitocondriais , Nocardia , Doença de Parkinson , Humanos , alfa-Sinucleína , Colite/induzido quimicamente , Neurônios
9.
Front Immunol ; 15: 1361231, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545095

RESUMO

Introduction: Nocardia seriolae adversely impacts a diverse range of fish species, exhibiting significant pathogenic characteristics that substantially impede the progress of aquaculture. N. seriolae infects in fish has a long incubation period, and clinical symptoms are not obvious in the early stages. There is presently no viable and eco-friendly approach to combat the spread of the disease. According to reports, N. seriolae primarily targets macrophages in tissues after infecting fish and can proliferate massively, leading to the death of fish. Interferon-gamma (IFN-γ) is a crucial molecule that regulates macrophage activation, but little is known about its role in the N. seriolae prevention. Methods: IFN-γ was first defined as largemouth bass (Micropterus salmoides, MsIFN-γ), which has a highly conserved IFN-γ characteristic sequence through homology analysis. The recombinant proteins (rMsIFN-γ) were obtained in Escherichia coli (E. coli) strain BL21 (DE3). The inflammatory response-inducing ability of rMsIFN-γ was assessed in vitro using monocytes/macrophages. Meanwhile, the protective effect of MsIFN-γ in vivo was evaluated by N. seriolae infection largemouth bass model. Results: In the inflammatory response of the monocytes/macrophages activated by rMsIFN-γ, various cytokines were significantly increased. Interestingly, interleukin 1ß (IL-1ß) and tumor necrosis factor alpha (TNF-a) increased by 183- and 12-fold, respectively, after rMsIFN-γ stimulation. rMsIFN-γ improved survival by 42.1% compared with the control. The bacterial load in the liver, spleen and head kidney significantly decreased. rMsIFN-γ was also shown to better induce increased expression of IL-1ß, TNF-α, hepcidin-1(Hep-1), major histocompatibility complex I (MHCI), and MHC II in head kidney, spleen and liver. The histopathological examination demonstrated the transformation of granuloma status from an early necrotic foci to fibrosis in the infection period. Unexpectedly, the development of granulomas was successfully slowed in the rMsIFN-γ group. Discussion: This work paves the way for further research into IFN-γ of largemouth bass and identifies a potential therapeutic target for the prevention of N. seriolae.


Assuntos
Bass , Nocardiose , Nocardia , Animais , Interferon gama , Escherichia coli , Nocardiose/prevenção & controle , Nocardiose/veterinária , Proteínas Recombinantes
11.
Biosens Bioelectron ; 254: 116208, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492361

RESUMO

Aquatic fishes are threatened by the strong pathogenic bacterium Nocardia seriolae, which challenges the current prevention and treatment approaches. This study introduces luminogens with aggregation-induced emission (AIE) as an innovative and non-antibiotic therapy for N. seriolae. Specifically, the AIE photosensitizer, TTCPy-3 is employed against N. seriolae. We evaluated the antibacterial activity of TTCPy-3 and investigated the killing mechanism against N. seriolae, emphasizing its ability to aggregate within the bacterium and produce reactive oxygen species (ROS). TTCPy-3 could effectively aggregate in N. seriolae, generate ROS, and perform real-time imaging of the bacteria. A bactericidal efficiency of 100% was observed while concentrations exceeding 4 µM in the presence of white light irradiation for 10 min. In vivo, evaluation on zebrafish (Danio rerio) confirmed the superior therapeutic efficacy induced by TTCPy-3 to fight against N. seriolae infections. TTCPy-3 offers a promising strategy for treating nocardiosis of fish, paving the way for alternative treatments beyond traditional antibiotics and potentially addressing antibiotic resistance.


Assuntos
Técnicas Biossensoriais , Doenças dos Peixes , Nocardiose , Nocardia , Animais , Peixe-Zebra , Espécies Reativas de Oxigênio , Nocardiose/tratamento farmacológico , Nocardiose/veterinária , Nocardiose/microbiologia , Peixes/microbiologia , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/microbiologia
13.
Antimicrob Agents Chemother ; 68(5): e0168623, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38534103

RESUMO

Nocardiosis typically requires a prolonged treatment duration of ≥6 months and initial combination therapy with 2-3 antibiotics. First-line regimens for nocardiosis are associated with considerable toxicity; therefore, alternative therapies are needed. Omadacycline is an aminomethylcycline with broad antimicrobial activity whose in vitro activity against Nocardia species has not been formally assessed. The in vitro potency of omadacycline was evaluated against 300 Nocardia clinical isolates by broth microdilution. The most common Nocardia species tested were N. cyriacigeorgica (21%), N. nova (20%), and N. farcinica (12%). The most common specimens were respiratory (178 isolates, 59%) and wound (57 isolates, 19%). Omadacycline minimum inhibitory concentrations (MICs) across all Nocardia species ranged from 0.06 µg/mL to 8 µg/mL, with an MIC50 of 2 µg/mL and MIC90 of 4 µg/mL. The lowest MICs were found among N. paucivorans (MIC50 = 0.25 µg/mL, MIC90 = 0.25 µg/mL), N. asiatica (MIC50 = 0.25 µg/mL, MIC90 = 1 µg/mL), N. abscessus complex (MIC50 = 0.5 µg/mL, MIC90 = 1 µg/mL), N. beijingensis (MIC50 = 0.5 µg/mL, MIC90 = 2 µg/mL), and N. otitidiscaviarum (MIC50 = 1 µg/mL, MIC90 = 2 µg/mL). The highest MICs were found among N. farcinica (MIC50 = 4 µg/mL, MIC90 = 8 µg/mL). In vitro potency differed by species among Nocardia clinical isolates. Further studies are warranted to evaluate the potential clinical utility of omadacycline for nocardiosis.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Nocardiose , Nocardia , Tetraciclinas , Nocardia/efeitos dos fármacos , Tetraciclinas/farmacologia , Antibacterianos/farmacologia , Humanos , Nocardiose/microbiologia , Nocardiose/tratamento farmacológico
14.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(3): 237-240, 2024 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-38448174

RESUMO

Nocardia is a rarely encountered opportunistic gram-positive bacterium that exhibits marked invasiveness and dissemination. Typically, acquired through trauma or inhalation, this pathogen primarily affects immunocompromised individuals and is a potentially life-threatening risk in severe cases. Nocardia otitidiscaviarum is a particularly rare subtype of Nocardia infection, and the occurrence of concurrent Aspergillus infection is extremely rare. In cases where both infections manifest concomitantly, rapid and accurate diagnosis is essential to facilitate the subsequent selection of appropriate anti-infective interventions. This paper reported the diagnostic and therapeutic experience in managing a case of pulmonary co-infection with Nocardia otitidiscaviarum and Aspergillus. The patient presented with an acute onset, rapid progression, and early manifestation of respiratory failure. The diagnostic process included respiratory pathogen culture and bronchoscopy, which was supplemented with targeted next-generation sequencing (tNGS). These comprehensive diagnostic modalities led to the identification of pulmonary co-infection with Nocardia otitidiscaviarum and Aspergillus. After adjustment of the antibiotic regimen, the patient's condition improved rapidly, culminating in a timely discharge.


Assuntos
Coinfecção , Nocardia , Pneumonia , Humanos , Aspergillus
15.
Sci Rep ; 14(1): 5342, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438563

RESUMO

The purpose of the present study was to evaluate the in vitro activity of tedizolid against several clinically significant species of Nocardia by comparing with that of linezolid. A total of 286 isolates of Nocardia species, including 236 clinical isolates recovered from patients in Japan and 50 strains (43 species) purchased from NITE Biological Resource Center, were studied. Antimicrobial susceptibility testing was performed using the broth microdilution method. For the 286 Nocardia isolates, the minimal inhibitory concentration (MIC)50 and MIC90 values of tedizolid were 0.25 and 0.5 µg/ml, and those of linezolid were 2 and 2 µg/ml, respectively. The distribution of the linezolid/tedizolid ratios (MICs of linezolid/MICs of tedizolid) showed that tedizolid had four- to eight-fold higher activity than linezolid in 96.1% (275/286) of Nocardia isolates. Both the tedizolid and linezolid MIC90 values for Nocardia brasiliensis were two-fold higher than those for the other Nocardia species. Both tedizolid and linezolid had low MIC values, 0.25-1 µg/ml and 0.5-4 µg/ml, respectively, even against nine isolates (five species) that were resistant to trimethoprim/sulfamethoxazole. One Nocardia sputorum isolate showed reduced susceptibility to tedizolid (4 µg/ml). Bioinformatics analysis suggests different resistance mechanisms than the oxazolidinone resistance seen in enterococci and staphylococci.


Assuntos
Nocardia , Oxazolidinonas , Humanos , Linezolida/farmacologia , Tetrazóis
16.
Invest Ophthalmol Vis Sci ; 65(3): 26, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38502137

RESUMO

Purpose: Nocardia keratitis is a serious and sight-threatening condition. This study aims to reveal the virulence and antimicrobial resistance gene profile of Nocardia strains using whole genome sequencing. Methods: Whole-genome sequencing was performed on 23 cornea-derived Nocardia strains. Together with genomic data from the respiratory tract and the environment, 141 genomes were then utilized for phylogenetic and pan-genome analyses, followed by virulence and antibiotic resistance analysis. The correlations between virulence genes and pathogenicity were experimentally validated, including the characteristics of Nocardia colonies and clinical and histopathological evaluations of Nocardia keratitis mice models. Results: Whole-genome sequencing of 141 Nocardia strains revealed a mean of 220 virulence genes contributed to bacterial pathogenesis. The mce gene family analysis led to the categorization of strains from the cornea into groups A, B, and C. The colonies of group C had the largest diameter, height, and fastest growth rate. The size of corneal ulcers and the clinical scores showed a significant increase in mouse models induced by group C. The relative expression levels of pro-inflammatory cytokines (CD4, IFN-γ, IL-6Rα, and TNF-α) in the lesion area exhibited an increasing trend from group A to group C. Antibiotic resistance genes (ARGs) spanned nine distinct drug classes, four resistance mechanisms, and seven primary antimicrobial resistance gene families. Conclusions: Whole genome sequencing highlights the pathogenic role of mce gene family in Nocardia keratitis. Its distribution pattern may contribute to the distinct characteristics of the growth of Nocardia colonies and the clinical severity of the mice models.


Assuntos
Ceratite , Nocardia , Animais , Camundongos , Filogenia , Ceratite/genética , Sequenciamento Completo do Genoma , Antibacterianos/farmacologia , Nocardia/genética
17.
Sci Rep ; 14(1): 5676, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453942

RESUMO

Actinobacteria are one of the predominant groups that successfully colonize and survive in various aquatic, terrestrial and rhizhospheric ecosystems. Among actinobacteria, Nocardia is one of the most important agricultural and industrial bacteria. Screening and isolation of Nocardia related bacteria from extreme habitats such as endolithic environments are beneficial for practical applications in agricultural and environmental biotechnology. In this work, bioinformatics analysis revealed that a novel strain Nocardia mangyaensis NH1 has the capacity to produce structurally varied bioactive compounds, which encoded by non-ribosomal peptide synthases (NRPS), polyketide synthase (PKS), and post-translationally modified peptides (RiPPs). Among NRPS, five gene clusters have a sequence homology with clusters encoding for siderophore synthesis. We also show that N. mangyaensis NH1 accumulates both catechol- and hydroxamate-type siderophores simultaneously under iron-deficient conditions. Untargeted LC-MS/MS analysis revealed a variety of metabolites, including siderophores, lipopeptides, cyclic peptides, and indole-3-acetic acid (IAA) in the culture medium of N. mangyaensis NH1 grown under iron deficiency. We demonstrate that four CAS (chrome azurol S)-positive fractions display variable affinity to metals, with a high Fe3+ chelating capability. Additionally, three of these fractions exhibit antioxidant activity. A combination of iron scavenging metabolites produced by N. mangyaensis NH1 showed antifungal activity against several plant pathogenic fungi. We have shown that the pure culture of N. mangyaensis NH1 and its metabolites have no adverse impact on Arabidopsis seedlings. The ability of N. mangyaensis NH1 to produce siderophores with antifungal, metal-chelating, and antioxidant properties, when supplemented with phytohormones, has the potential to improve the release of macro- and micronutrients, increase soil fertility, promote plant growth and development, and enable the production of biofertilizers across diverse soil systems.


Assuntos
Actinobacteria , Nocardia , Nocardia/genética , Nocardia/metabolismo , Sideróforos/metabolismo , Ecossistema , Antifúngicos/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Actinobacteria/metabolismo , Ferro/metabolismo , Bactérias/metabolismo , Genômica , Metaboloma , Solo
18.
Ann Clin Microbiol Antimicrob ; 23(1): 23, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38449006

RESUMO

BACKGROUND: The aim of this study was to investigate the clinical features of Nocardia infections, antibiotic resistance profile, choice of antibiotics and treatment outcome, among others. In addition, the study compared the clinical and microbiological characteristics of nocardiosis in bronchiectasis patients and non-bronchiectasis patients. METHODS: Detailed clinical data were collected from the medical records of 71 non-duplicate nocardiosis patients from 2017 to 2023 at a tertiary hospital in Zhengzhou, China. Nocardia isolates were identified to the species level using MALDI-TOF MS and 16S rRNA PCR sequencing. Clinical data were collected from medical records, and drug susceptibility was determined using the broth microdilution method. RESULTS: Of the 71 cases of nocardiosis, 70 (98.6%) were diagnosed as pulmonary infections with common underlying diseases including bronchiectasis, tuberculosis, diabetes mellitus and chronic obstructive pulmonary disease (COPD). Thirteen different strains were found in 71 isolates, the most common of which were N. farcinica (26.8%) and N. cyriacigeorgica (18.3%). All Nocardia strains were 100% susceptible to both TMP-SMX and linezolid, and different Nocardia species showed different patterns of drug susceptibility in vitro. Pulmonary nocardiosis is prone to comorbidities such as bronchiectasis, diabetes mellitus, COPD, etc., and Nocardia is also frequently accompanied by co-infection of the body with pathogens such as Mycobacterium and Aspergillus spp. Sixty-one patients underwent a detailed treatment regimen, of whom 32 (52.5%) received single or multi-drug therapy based on TMP-SMX. Bronchiectasis was associated with a higher frequency of Nocardia infections, and there were significant differences between the bronchiectasis and non-bronchiectasis groups in terms of age distribution, clinical characteristics, identification of Nocardia species, and antibiotic susceptibility (P < 0.05). CONCLUSIONS: Our study contributes to the understanding of the species diversity of Nocardia isolates in Henan, China, and the clinical characteristics of patients with pulmonary nocardiosis infections. Clinical and microbiologic differences between patients with and without bronchiectasis. These findings will contribute to the early diagnosis and treatment of patients.


Assuntos
Bronquiectasia , Diabetes Mellitus , Nocardiose , Nocardia , Doença Pulmonar Obstrutiva Crônica , Humanos , Nocardia/genética , RNA Ribossômico 16S/genética , Combinação Trimetoprima e Sulfametoxazol , Nocardiose/tratamento farmacológico , China , Bronquiectasia/tratamento farmacológico , Resistência a Medicamentos
19.
Vet Med Sci ; 10(3): e1433, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38520249

RESUMO

A 3-year-old Holstein cow was examined in an intensive system due to unilateral swelling in the mandible. A right mandibular mass was associated with painful mastication and Ptyalism. In palpation, the mass was raised, ulcerated, attached to the mandible bone and firm, approximately 17 × 12 × 10 cm3 in size. The lesion was sampled, and after routine bacteriology and histopathology procedures, the occurrence of lumpy jaw caused by Nocardia farcinica was confirmed. The bacterium was analysed using genome sequencing and new strain called Najm 114. Due to the risk of zoonosis of the isolated agent, the cow was euthanized. This is the first report of lumpy jaw caused by N. farcinica in a cow. This study showed that N. farcinica should be considered a possible etiological agent for lumpy jaw in cattle.


Assuntos
Doenças dos Bovinos , Nocardiose , Nocardia , Feminino , Bovinos , Animais , Nocardiose/diagnóstico , Nocardiose/veterinária , Sequência de Bases , Zoonoses , Doenças dos Bovinos/microbiologia
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