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1.
Microb Drug Resist ; 30(9): 354-362, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39029506

RESUMO

Background: Biofilm production in nonfermenting Gram-negative bacteria influences drug resistance. The aim of this work was to evaluate the effect of different antibiotics on biofilm eradication of clinical isolates of Achromobacter, Burkholderia, and Stenotrophomonas maltophilia. Methods: Clinical isolates were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry in a third-level hospital in Monterrey, Mexico. Crystal violet staining was used to determine biofilm production. Drug susceptibility testing was determined by broth microdilution in planktonic cells and biofilm cells. Results: Resistance in planktonic cells was moderate to trimethoprim-sulfamethoxazole, and low to chloramphenicol, minocycline, levofloxacin (S. maltophilia and Burkholderia), ceftazidime, and meropenem (Burkholderia and Achromobacter). Biofilm eradication required higher drug concentrations of ceftazidime, chloramphenicol, levofloxacin, and trimethoprim-sulfamethoxazole than planktonic cells (p < 0.05). Levofloxacin showed biofilm eradication activity in S. maltophilia, minocycline and meropenem in Burkholderia, and meropenem in Achromobacter. Conclusions: Drug resistance increased due to biofilm production for some antibiotics, particularly ceftazidime and trimethoprim-sulfamethoxazole for all three pathogens, chloramphenicol for S. maltophilia and Burkholderia, and levofloxacin for Burkholderia. Some antibiotics could be used for the treatment of biofilm-associated infections in our population, such as levofloxacin for S. maltophilia, minocycline and meropenem for Burkholderia, and meropenem for Achromobacter.


Assuntos
Achromobacter , Antibacterianos , Biofilmes , Burkholderia , Infecções por Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Stenotrophomonas maltophilia , Biofilmes/efeitos dos fármacos , Stenotrophomonas maltophilia/efeitos dos fármacos , Antibacterianos/farmacologia , Humanos , Burkholderia/efeitos dos fármacos , Achromobacter/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Farmacorresistência Bacteriana , Combinação Trimetoprima e Sulfametoxazol/farmacologia , México , Ceftazidima/farmacologia , Plâncton/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Levofloxacino/farmacologia
2.
Biofouling ; 40(8): 514-526, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39077794

RESUMO

Efflux pump inhibitors are a potential therapeutic strategy for managing antimicrobial resistance and biofilm formation. This article evaluated the effect of carbonyl cyanide m-chlorophenyl hydrazone (CCCP) on the biofilm growth dynamics and the production of virulence factors by Burkholderia pseudomallei. The effects of CCCP on planktonic, growing, and mature biofilm, interaction with antibacterial drugs, and protease and siderophore production were assessed. CCCP MICs ranged between 128 and 256 µM. The CCCP (128 µM) had a synergic effect with all the antibiotics tested against biofilms. Additionally, CCCP reduced (p < .05) the biomass of biofilm growth and mature biofilms at 128 and 512 µM, respectively. CCCP also decreased (p < .05) protease production by growing (128 µM) and induced (p < .05) siderophore release by planktonic cells (128 µM) growing biofilms (12.8 and 128 µM) and mature biofilms (512 µM). CCCP demonstrates potential as a therapeutic adjuvant for disassembling B. pseudomallei biofilms and enhancing drug penetration.


Assuntos
Antibacterianos , Biofilmes , Burkholderia pseudomallei , Carbonil Cianeto m-Clorofenil Hidrazona , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases , Sideróforos , Biofilmes/efeitos dos fármacos , Sideróforos/farmacologia , Burkholderia pseudomallei/efeitos dos fármacos , Burkholderia pseudomallei/fisiologia , Antibacterianos/farmacologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Peptídeo Hidrolases/metabolismo , Fatores de Virulência
3.
Artigo em Inglês | MEDLINE | ID: mdl-38904883

RESUMO

Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia are considered emerging pathogens classified as a public health problem due to extensive antimicrobial resistance. Therefore, the discovery of new therapeutic strategies has become crucial. This study aimed to evaluate the antimicrobial activity of gallic acid and methyl gallate against non-fermenting bacteria. The study included five clinical isolates of Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia. The minimum inhibitory concentrations of gallic acid and methyl gallate were determined by the broth microdilution method. Growth curves, metabolic activity, and biofilm formation of each bacterial strain in the presence or absence of phenolic compounds were performed. Finally, the therapeutic efficacy of the compounds was evaluated using an in vivo model. Gallic acid and methyl gallate showed antibacterial activity against bacterial strains in a concentration range of 64 to 256 µg/mL, both compounds reduced bacterial growth and metabolic activity of the strains, even at subinhibitory concentrations. Only, methyl gallate exhibited activity to inhibit the formation of bacterial biofilms. Moreover, gallic acid and methyl gallate increased larval survival by up to 60% compared to 30% survival of untreated larvae in a bacterial infection model in Galleria mellonella. Our results highlight the potential of gallic acid and methyl gallate as therapeutic alternatives for infections by emerging non-fermentative bacteria.

4.
Plant Dis ; 108(8): 2376-2388, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38386299

RESUMO

Burkholderia glumae causes bacterial leaf blight in rice, and its global spread has been exacerbated by climate change. To understand the genetic diversity and virulence of B. glumae strains isolated from rice cultivars in Perú, 47 isolates were obtained from infected rice fields, all belonging to B. glumae, and confirmed by recA and toxB sequences. The BOX-PCR typing group has 38 genomic profiles, and these turn into seven variable number tandem repeats (VNTR) haplotypes. There was no correlation between clustering and geographical origin. Nineteen strains were selected for phenotypic characterization and virulence, using both the maceration level of the onion bulb proxy and inoculation of seeds of two rice cultivars. Several strains produced pigments other than toxoflavin, which correlated with onion bulb maceration. In terms of virulence at the seed level, all strains produced inhibition at the root and coleoptile level, but the severity of symptoms varied significantly between strains, revealing significant differences in pathogenicity. There is no correlation between maceration and virulence scores, probably reflecting different virulence mechanisms depending on the host infection stage. This is the first study to evaluate the VNTR diversity and virulence of Peruvian strains of B. glumae in two commercial cultivars.


Assuntos
Burkholderia , Variação Genética , Oryza , Doenças das Plantas , Oryza/microbiologia , Burkholderia/genética , Burkholderia/patogenicidade , Burkholderia/isolamento & purificação , Doenças das Plantas/microbiologia , Virulência/genética , Filogenia , Repetições Minissatélites
5.
J Appl Microbiol ; 135(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364306

RESUMO

AIM: The increased availability of genome sequences has enabled the development of valuable tools for the prediction and identification of bacterial natural products. Burkholderia catarinensis 89T produces siderophores and an unknown potent antifungal metabolite. The aim of this work was to identify and purify natural products of B. catarinensis 89T through a genome-guided approach. MATERIALS AND METHODS: The analysis of B. catarinensis 89T genome revealed 16 clusters putatively related to secondary metabolism and antibiotics production. Of particular note was the identification of a nonribosomal peptide synthetase (NRPS) cluster related to the production of the siderophore ornibactin, a hybrid NRPS-polyketide synthase Type 1 cluster for the production of the antifungal glycolipopeptide burkholdine, and a gene cluster encoding homoserine lactones (HSL), probably involved in the regulation of both metabolites. We were able to purify high amounts of the ornibactin derivatives D/C6 and F/C8, while also detecting the derivative B/C4 in mass spectrometry investigations. A group of metabolites with molecular masses ranging from 1188 to 1272 Da could be detected in MS experiments, which we postulate to be new burkholdine analogs produced by B. catarinensis. The comparison of B. catarinensis BGCs with other Bcc members corroborates the hypothesis that this bacterium could produce new derivatives of these metabolites. Moreover, the quorum sensing metabolites C6-HSL, C8-HSL, and 3OH-C8-HSL were observed in LC-MS/MS analysis. CONCLUSION: The new species B. catarinensis is a potential source of new bioactive secondary metabolites. Our results highlight the importance of genome-guided purification and identification of metabolites of biotechnological importance.


Assuntos
4-Butirolactona/análogos & derivados , Produtos Biológicos , Complexo Burkholderia cepacia , Burkholderia , Lipopeptídeos , Sideróforos/metabolismo , Antifúngicos/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Burkholderia/genética , Burkholderia/metabolismo , Complexo Burkholderia cepacia/metabolismo , Produtos Biológicos/metabolismo , Proteínas de Bactérias/genética
6.
Ann Med ; 56(1): 2307503, 2024 12.
Artigo em Inglês | MEDLINE | ID: mdl-38261606

RESUMO

Burkholderia cepacia complex (Bcc) is a bacterial group with 'natural' multi-antimicrobial resistance. This complex has generated epidemic outbreaks across the world. In people with cystic fibrosis (CF), Bcc can cause severe lung infections that lead to accelerated lung damage, which can be complicated by necrotizing pneumonia accompanied by high fevers, leucocytosis, and bacteraemia, which commonly causes fatal outcomes. Specifically, infection by Burkholderia cenocepacia is considered an exclusion criterion for lung transplantation. The species of Bcc exhibit both genetic and phenotypic hypervariability that complicate their accurate microbiological identification. Automated methods such as MALDI-TOF can err in the determination of species. Their slow growth even in selective agars and the absence of international consensuses on the optimal conditions for their isolation make early diagnosis a difficult challenge to overcome. The absence of correlations between antibiograms and clinical results has resulted in the absence of standardized cut-off values of antimicrobial susceptibility, a fact that brings a latent risk since incorrect antibiotic therapy can induce the selection of more aggressive variants that worsen the clinical picture of the host, added to the absence of a clear therapeutic guide for the eradication of pulmonary infections by Bcc in patients with CF, resulting in frequently ineffective treatments. There is an urgent need to standardize methods and diagnostic tools that would allow an early and accurate diagnosis, as well as to perform clinical studies of the effectiveness of available antibiotics to eradicate Bcc infections, which would allow us to establish standardized therapeutic schemes for Bcc-infected patients.


Assuntos
Bacteriemia , Complexo Burkholderia cepacia , Fibrose Cística , Transplante de Pulmão , Humanos , Antibacterianos
7.
Comp Immunol Microbiol Infect Dis ; 105: 102122, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219337

RESUMO

Brazil is strategic in controlling neglected zoonoses, such as glanders, in its territory. Among the Brazilian states, Piauí is a strategic state for the spread of the disease in the country. The present study aimed to evaluate the spatial and temporal distribution of official cases of glanders in Piauí between 2015 and 2022. The glanders cases were located in the municipalities of the north and central-north mesoregions, mainly in Campo Maior, Teresina and Altos. The highest incidence risk (IR) occurred in of Altos (IR = 257.9), Sussuapara (IR = 158.4), and Teresina (IR = 157.7). A primary cluster was formed with a relative risk of 14.88 between 2019 and 2022, encompassing 34 municipalities in the north and central-north regions. In Piauí, glanders is well localized, with the potential for spread across borders. This is the first study demonstrating the distribution of reported cases of glanders in the state of Piauí.


Assuntos
Burkholderia mallei , Mormo , Doenças dos Cavalos , Animais , Cavalos , Brasil/epidemiologia , Zoonoses/epidemiologia
8.
Appl Environ Microbiol ; 89(12): e0063023, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38054732

RESUMO

IMPORTANCE: Fusaric acid (FA) is an important virulence factor produced by several Fusarium species. These fungi are responsible for wilt and rot diseases in a diverse range of crops. FA is toxic for animals, humans and soil-borne microorganisms. This mycotoxin reduces the survival and competition abilities of bacterial species able to antagonize Fusarium spp., due to its negative effects on viability and the production of antibiotics effective against these fungi. FA biodegradation is not a common characteristic among bacteria, and the determinants of FA catabolism have not been identified so far in any microorganism. In this study, we identified genes, enzymes, and metabolic pathways involved in the degradation of FA in the soil bacterium Burkholderia ambifaria T16. Our results provide insights into the catabolism of a pyridine-derivative involved in plant pathogenesis by a rhizosphere bacterium.


Assuntos
Complexo Burkholderia cepacia , Burkholderia , Fusarium , Micotoxinas , Animais , Humanos , Micotoxinas/metabolismo , Ácido Fusárico/metabolismo , Burkholderia/metabolismo , Complexo Burkholderia cepacia/metabolismo , Fungos/metabolismo , Solo , Fusarium/metabolismo , Doenças das Plantas/microbiologia
9.
Pathogens ; 12(10)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37887766

RESUMO

This manuscript elucidates the occurrence of glanders in an asymptomatic mare from Brazil presenting positive Burkholderia mallei antibody titers. The diagnosis was established through a multi-pronged approach encompassing microbiological culture, mass spectrometry, and genome sequencing. The outbreak occurred in 2019 in Tatuí, São Paulo, Brazil, and the infected mare, despite displaying no clinical symptoms, had multiple miliary lesions in the liver, as well as intense catarrhal discharge in the trachea. Samples were collected from various organs and subjected to bacterial isolation, molecular detection, and identification. The strain was identified as B. mallei using PCR and confirmed by MALDI-TOF mass spectrometry. Whole-genome sequencing revealed a genome size of 5.51 Mb with a GC content of 65.8%, 5871 genes (including 4 rRNA and 53 tRNA genes), and 5583 coding DNA sequences (CDSs). Additionally, 227 predicted pseudogenes were detected. In silico analysis of different genomic loci that allow for differentiation with Burkholderia pseudomallei confirmed the identity of the isolate as B. mallei, in addition to the characteristic genome size. The BAC 86/19 strain was identified as lineage 3, sublineage 2, which includes other strains from Brazil, India, and Iran. The genome sequencing of this strain provides valuable information that can be used to better understand the pathogen and its epidemiology, as well as to develop diagnostic tools for glanders.

10.
J Med Case Rep ; 17(1): 362, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37608318

RESUMO

BACKGROUND: Melioidosis is a serious disease caused by the bacterium Burkholderia pseudomallei which affects humans and animals. It results in a wide spectrum of clinical manifestations, mainly in the respiratory tract, progressing to septic shock and death. CASE PRESENTATION: Herein, we present a series of seven patients (median age: 41 years) with confirmed melioidosis, treated at a public hospital in Piauí State, Brazil between 2019 and 2021. The most common clinical presentations were fever, cough, pneumonia, and abdominal pain. The mean duration of antibacterial therapy with 1 g of meropenem was 28.6 ± 1.1 days. Six patients recovered and one died. The mean hospitalization time was 51.0 ± 39.2 days. CONCLUSIONS: Melioidosis is an emerging infectious disease in Brazil. Health professionals in endemic areas need to be aware of the clinical presentation and appropriate clinical management of the disease because early diagnosis and early initiation of antibiotic therapy can be life-saving.


Assuntos
Burkholderia pseudomallei , Melioidose , Adulto , Humanos , Dor Abdominal , Antibacterianos/uso terapêutico , Brasil/epidemiologia , Melioidose/diagnóstico , Melioidose/tratamento farmacológico
11.
Future Microbiol ; 18: 785-794, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37622278

RESUMO

Aim: This study evaluated the effect of fluoxetine (FLU) on planktonic and biofilm growth and the antimicrobial susceptibility of Burkholderia pseudomallei. Materials & methods: The minimum inhibitory concentrations (MICs) for FLU were determined by broth microdilution. Its effect on growing and mature biofilms and its interaction with antibacterial drugs were evaluated by assessing biofilm metabolic activity, biomass and structure through confocal microscopy. Results: The FLU MIC range was 19.53-312.5 µg/ml. FLU eradicated growing and mature biofilms of B. pseudomallei at 19.53-312.5 µg/ml and 1250-2500 µg/ml, respectively, with no structural alterations and enhanced the antibiofilm activity of antimicrobial drugs. Conclusion: These results bring perspectives for the use of FLU in the treatment of melioidosis, requiring further studies to evaluate its applicability.


Assuntos
Anti-Infecciosos , Burkholderia pseudomallei , Fluoxetina/farmacologia , Plâncton , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana
12.
Biofouling ; 39(2): 135-144, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-37013808

RESUMO

This study evaluated the effect of the iron chelator deferiprone (DFP) on antimicrobial susceptibility and biofilm formation and maintenance by Burkholderia pseudomallei. Planktonic susceptibility to DFP alone and in combination with antibiotics was evaluated by broth microdilution and biofilm metabolic activity was determined with resazurin. DFP minimum inhibitory concentration (MIC) range was 4-64 µg/mL and in combination reduced the MIC for amoxicillin/clavulanate and meropenem. DFP reduced the biomass of biofilms by 21 and 12% at MIC and MIC/2, respectively. As for mature biofilms, DFP reduced the biomass by 47%, 59%, 52% and 30% at 512, 256, 128 and 64 µg/mL, respectively, but did not affect B. pseudomallei biofilm viability nor increased biofilm susceptibility to amoxicillin/clavulanate, meropenem and doxycycline. DFP inhibits planktonic growth and potentiates the effect of ß-lactams against B. pseudomallei in the planktonic state and reduces biofilm formation and the biomass of B. pseudomallei biofilms.


Assuntos
Burkholderia pseudomallei , Meropeném/farmacologia , Deferiprona/farmacologia , Ferro/farmacologia , Ferro/metabolismo , Biofilmes , Antibacterianos/farmacologia , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Testes de Sensibilidade Microbiana , Quelantes de Ferro/farmacologia
13.
Syst Appl Microbiol ; 46(3): 126415, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933352

RESUMO

Two putative novel Burkholderia cenocepacia lineages found in the semi-arid region of north-east Brazil causing onion sour skin were studied using genomic approaches to determine their taxonomic position. Four strains belonging to one novel lineage (CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171) and one strain (CCRMBC51) belonging to another novel lineage had their whole genome sequenced to carry out taxogenomic analyses. The phylogenomic tree built using the type (strain) genome server (TYGS) clustered the strains CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171 into the same clade, while grouped the strain CCRMBC51 separately. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) analysis showed values above 99.21 % and 93.2 %, respectively, among the strains CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171, while ANI and dDDH values between these strains and the strain CCRMBC51 were below 94.49 % and 56.6 %, respectively. All these strains showed ANI and dDDH values below 94.78 % and 58.8 % concerning type strains of the B. cepacia complex (Bcc) species. The phylogenetic maximum likelihood tree constructed based on the multilocus sequence analysis of core genes (cMLSA) clustered the strains CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171 and the strain CCRMBC51 in two exclusive clades, which did not cluster with any known species of the Bcc. Therefore, combined data from TYGS, ANI, dDDH, and cMLSA demonstrated that the strains represent two novel species of the Bcc, which we classified as Burkholderia semiarida sp. nov. and Burkholderia sola sp. nov., and proposed the strains CCRMBC74T (=IBSBF 3371 T = CBAS 905 T) and CCRMBC51T (=IBSBF3370T = CBAS 904 T) as type strains, respectively.


Assuntos
Burkholderia , Burkholderia/genética , Cebolas/genética , Análise de Sequência de DNA , Filogenia , RNA Ribossômico 16S/genética , Hibridização de Ácido Nucleico , DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Ácidos Graxos
14.
Pathog Dis ; 812023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36963774

RESUMO

Burkholderia contaminans, a species of the Burkholderia cepacia complex-prevalent in certain Latin-American and European countries-can cause chronic pulmonary infection in persons with cystic fibrosis. Our aim was to gain insights into long-term lung infections with a focus on correlating how bacterial phenotypic traits in the chronic infection impact on patients' clinical outcome. Genotypic characteristics of 85 B. contaminans isolates recovered from 70 patients were investigated. For 16 of those patients, the clinical status and bacterial phenotypic characteristics, e.g. several virulence factors, phenotypic variants, and the antimicrobial susceptibility pattern, were evaluated. Two clones were found in the whole bacterial population: (i) the multiresistant ST 872 PCR-recA-RFLP-HaeIII-K-pattern clone, which carries a pathogenic island homologous to BcenGI11 of B. cenocepacia J2315, and (ii) the ST 102 PCR-recA-RFLP-HaeIII-AT-pattern clone. The emergence of certain bacterial phenotypes in the chronic infection such as the nonmucoid phenotype, small colony variants, brownish pigmented colonies, and hypermutators, proved to be, together with coinfection with Pseudomonas aeruginosa, the possible markers of more challenging infections and poor prognosis. The presence of cocolonizers and the bacterial phenotypes that are especially adapted to persist in long-term respiratory tract infections have a crucial role in patients' clinical outcomes.


Assuntos
Infecções por Burkholderia , Complexo Burkholderia cepacia , Fibrose Cística , Pneumonia , Humanos , Infecção Persistente , Fibrose Cística/complicações , Fibrose Cística/microbiologia , Pulmão/microbiologia , Fenótipo , Infecções por Burkholderia/microbiologia
15.
Molecules ; 28(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36838633

RESUMO

Due to the increase in multidrug-resistant microorganisms, the investigation of novel or more efficient antimicrobial compounds is essential. The World Health Organization issued a list of priority multidrug-resistant bacteria whose eradication will require new antibiotics. Among them, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacteriaceae are in the "critical" (most urgent) category. As a result, major investigations are ongoing worldwide to discover new antimicrobial compounds. Burkholderia, specifically Burkholderia sensu stricto, is recognized as an antimicrobial-producing group of species. Highly dissimilar compounds are among the molecules produced by this genus, such as those that are unique to a particular strain (like compound CF66I produced by Burkholderia cepacia CF-66) or antimicrobials found in a number of species, e.g., phenazines or ornibactins. The compounds produced by Burkholderia include N-containing heterocycles, volatile organic compounds, polyenes, polyynes, siderophores, macrolides, bacteriocins, quinolones, and other not classified antimicrobials. Some of them might be candidates not only for antimicrobials for both bacteria and fungi, but also as anticancer or antitumor agents. Therefore, in this review, the wide range of antimicrobial compounds produced by Burkholderia is explored, focusing especially on those compounds that were tested in vitro for antimicrobial activity. In addition, information was gathered regarding novel compounds discovered by genome-guided approaches.


Assuntos
Anti-Infecciosos , Bacteriocinas , Burkholderia cepacia , Burkholderia , Antibacterianos
16.
Expert Rev Anti Infect Ther ; 21(2): 213-223, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36625029

RESUMO

BACKGROUND: Non-fermenting Gram-negative Achromobacter xylosoxidans, Burkholderia cepacia complex, and Stenotrophomonas maltophilia species cause healthcare-associated infections, often showing resistance to first-line drugs such as trimethoprim-sulfamethoxazole (TMP-SXT). The aim of this study was to determine the effect of curcumin-chitosan nanocomplexes on biofilm-producing clinical isolates of non-fermenting Gram-negative bacilli. METHODS: A. xylosoxidans, B. cepacia complex, and S. maltophilia clinical isolates were identified by MALDI-TOF mass spectrometry. Antimicrobial susceptibility was determined by broth microdilution. Curcumin (Cur), chitosan (Chi), and sodium tripolyphosphate (TPP) were encapsulated by ionotropic gelation in magnetic nanoparticles (MNP) and were assessed by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR). Biofilm inhibition and eradication by Cur-Chi-TPP-MNP with TMP-SXT was assessed. RESULTS: Cur-Chi-TPP-MNP in combination with TMP-SXT showed biofilm inhibition activity in A. xylosoxidans (37.5 µg/mL), B. cepacia (18.75 µg/mL), and S. maltophilia (4.69-18.75 µg/mL) and low biofilm eradication activity in all three strains (150 - 300 µg/mL). CONCLUSIONS: Cur-Chi-TPP-MNP in combination with TMP-SXT was able to inhibit biofilm and in lower effect to eradicate established biofilms of clinical isolates of A. xylosoxidans, B. cepacia complex, and S. maltophilia species. Our results highlight the need to assess these potential treatment options to be used clinically in biofilm-associated infections.


Assuntos
Achromobacter , Burkholderia , Quitosana , Curcumina , Infecções por Bactérias Gram-Negativas , Stenotrophomonas maltophilia , Humanos , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Curcumina/farmacologia , Stenotrophomonas , Quitosana/farmacologia , Quitosana/uso terapêutico , Biofilmes , Testes de Sensibilidade Microbiana , Infecções por Bactérias Gram-Negativas/tratamento farmacológico
17.
Braz J Microbiol ; 54(1): 361-370, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36574205

RESUMO

Peanut stem rot caused by Sclerotium rolfsii Sacc. is the most common disease of peanut worldwide and has become increasingly serious in recent years. This study is aimed at obtaining peanut endophytic bacteria with high antagonistic/protective effects against peanut stem rot. In total, 45 bacterial strains were isolated from healthy peanut plants from a severely impacted area. Of these, 6 exhibited antagonistic activity against S. rolfsii, including F-1 and R-11 with the most robust activity with an inhibition zone width of 20.25 and 15.49 mm, respectively. These two were identified as Bacillus sp. and Burkholderia sp., respectively, based on morphological, physiological, and biochemical characteristics and 16S rDNA sequencing. To the best of our knowledge, this is the first study to report the Burkholderia sp. antagonistic effect on S. rolfsii as a biological control agent for peanut stem rot. Their culture filtrates potently inhibited the hyphal growth, sclerotial formation, and germination of S. rolfsii. Also, the strain-produced volatile compounds inhibited the fungal growth. Pot experiments showed that F-1 and R-11 significantly reduced the peanut stem rot disease with the efficacy of 77.13 and 64.78%, respectively, which was significantly higher compared with carbendazim medicament (35.22%; P < 0.05). Meanwhile, F-1 and R-11 improved the activity of plant defense enzymes such as phenylalaninase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) enhancing the systemic resistance of the peanut plants. This study demonstrated that Bacillus sp. F-1 and Burkholderia sp. R-11, with a strong antagonistic effect on S. rolfsii, can be potential biocontrol agents for peanut stem rot.


Assuntos
Ascomicetos , Bacillus , Basidiomycota , Arachis/microbiologia , Ascomicetos/fisiologia , Bacillus/genética
18.
Methods Mol Biol ; 2610: 137-147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36534288

RESUMO

Rhizopus microsporus is an early-diverging fungal species that inhabits the soil, is used for the fermentation of diverse Asian and African foods, and can be a pathogen of plants, animals, and humans.Toxin-producing strains of R. microsporus live in symbiosis with Gram-negative betaproteobacteria from the genus Mycetohabitans (Burkholderia sensu lato). These bacterial endosymbionts increase the metabolic plasticity of the fungal holobiont by producing the "mycotoxins," control their asexual reproduction, and influence their sexual success. Recently, we identified two viruses of the genus Narnavirus in some R. microsporus strains that harbor Mycetohabitans. By eliminating bacteria and/or viruses from host R. microsporus strains, we have been able to study the role of these symbionts in fungal biology. Remarkably, the absence of these bacterial and viral symbionts decreases sexual reproduction. In this chapter, the method developed to eliminate and genotype the Narnavirus RmNV-20S and RmNV-23S in R. microsporus is described in detail.


Assuntos
Bacteriófagos , Burkholderia , Humanos , Simbiose/genética , Burkholderia/genética , Burkholderia/metabolismo , Reprodução , Reprodução Assexuada , Rhizopus/genética
19.
Diagn Microbiol Infect Dis ; 105(2): 115866, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36525921

RESUMO

Burkholderia cepacia complex (Bcc) species are opportunistic pathogens widely distributed in the environment and often infect people with cystic fibrosis (CF). This study aims to determine which genomovars of the Bcc can cause infections in non-CF patients from a tertiary care hospital in Mexico and if they carry virulence factors that could increase their pathogenicity. We identified 23 clinical isolates that carry the recA gene. Twenty-two of them belongs to the genomovar V (B. vietnamiensis) and one to the genomovar II (B. multivorans). Thirteen pulsotypes were identified among 22 B. vietnamiensis isolates. All clinical isolates produced biofilm were motile and cytotoxic on murine macrophage-like RAW264.7 and in A549 human lung epithelial cells. In conclusion, B. vietnamiensis causes infections in non-CF patients in a tertiary care hospital in Mexico, rapid identification of this pathogen can help physicians to establish a better antimicrobial treatment.


Assuntos
Infecções por Burkholderia , Complexo Burkholderia cepacia , Burkholderia cepacia , Fibrose Cística , Humanos , Animais , Camundongos , Burkholderia cepacia/genética , Infecções por Burkholderia/epidemiologia , México/epidemiologia , Centros de Atenção Terciária , Reação em Cadeia da Polimerase , Complexo Burkholderia cepacia/genética , Fibrose Cística/complicações
20.
Microorganisms ; 12(1)2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38257866

RESUMO

This review was conducted to assess the global incidence of transfusion-transmitted infections (TTIs) caused by contamination of blood components with the Burkholderia cepacia complex (Bcc). Our search encompassed various specialized databases such as Medline/PubMed, Web of Science, Scopus, Scielo, ScienceDirect, and ClinicalKey. An analysis of the literature revealed a total of eleven reported cases where blood components contaminated with Bcc had been transfused, resulting in sepsis among the affected patients. Of these cases, eight were documented in the literature, while the remaining three occurred within the institution involving the authors of this review. A comparative examination was conducted, considering factors such as primary diagnosis, transfused blood component, time elapsed between transfusion and manifestation of symptoms, administration of antibiotics, and final outcome. Interestingly, regardless of the storage temperature, all blood components were found to be susceptible to Bcc contamination. Furthermore, the cases investigated revealed diverse sources of contamination, and it was observed that all the affected patients had compromised immune systems due to underlying illnesses. Based on these findings, a series of preventive strategies were derived to mitigate and decrease the occurrence of similar cases.

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