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1.
PLoS One ; 19(4): e0298577, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635685

RESUMO

BACKGROUND: Infections caused by Stenotrophomonas maltophilia and related species are increasing worldwide. Unfortunately, treatment options are limited, whereas the antimicrobial resistance is increasing. METHODS: We included clinical isolates identified as S. maltophilia by VITEK 2 Compact. Ceftazidime/avibactam, meropenem/vaborbactam, imipenem/relebactam, cefiderocol, quinolones, and tetracycline family members were evaluated by broth microdilution method and compared with first-line treatment drugs. Minimum inhibitory concentrations (MICs) were reported for all antibiotics. We sequenced the Whole Genome of cefiderocol resistant strains (CRSs) and annotated their genes associated with cefiderocol resistance (GACR). Presumptive phylogenetic identification employing the 16S marker was performed. RESULTS: One hundred and one clinical strains were evaluated, sulfamethoxazole and trimethoprim, levofloxacin and minocycline showed susceptibilities of 99.01%, 95.04% and 100% respectively. Ceftazidime was the antibiotic with the highest percentage of resistance in all samples (77.22%). Five strains were resistant to cefiderocol exhibiting MIC values ≥ 2 µg/mL (4.95%). The ß-lactamase inhibitors meropenem/vaborbactam and imipenem/relebactam, failed to inhibit S. maltophilia, preserving both MIC50 and MIC90 ≥64 µg/mL. Ceftazidime/avibactam restored the activity of ceftazidime decreasing the MIC range. Tigecycline had the lowest MIC range, MIC50 and MIC90. Phylogeny based on 16S rRNA allowed to identify to cefiderocol resistant strains as putative species clustered into Stenotrophomonas maltophilia complex (Smc). In these strains, we detected GARCs such as Mutiple Drug Resistance (MDR) efflux pumps, L1-type ß-lactamases, iron transporters and type-1 fimbriae. CONCLUSION: Antimicrobial resistance to first-line treatment is low. The in vitro activity of new ß-lactamase inhibitors against S. maltophilia is poor, but avibactam may be a potential option. Cefiderocol could be considered as a potential new option for multidrug resistant infections. Tetracyclines had the best in vitro activity of all antibiotics evaluated.


Assuntos
Ácidos Borônicos , Ceftazidima , Stenotrophomonas maltophilia , Ceftazidima/farmacologia , 60607 , Meropeném , Inibidores de beta-Lactamases/farmacologia , Inibidores de beta-Lactamases/uso terapêutico , Stenotrophomonas , Filogenia , RNA Ribossômico 16S , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Compostos Azabicíclicos/farmacologia , Combinação de Medicamentos , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-38393318

RESUMO

During the analysis of a collection of Pseudomonas strains linked to an outbreak in an intensive care unit at King Faisal Specialist Hospital and Research Center in 2019, one isolate (CFS3442T) was identified phenotypically as Pseudomonas aeruginosa. However, whole-genome sequencing revealed its true identity as a member of the genus Stenotrophomonas, distinct from both P. aeruginosa and Stenotrophomonas maltophilia. The isolate demonstrated: (i) a significant phylogenetic distance from P. aeruginosa; (ii) considerable genomic differences from several S. maltophilia reference strains and other Stenotrophomonas species; and (iii) unique phenotypic characteristics. Based on the combined geno- and phenotypic data, we propose that this isolate represents a novel species within the genus Stenotrophomonas, for which the name Stenotrophomonas riyadhensis sp. nov. is proposed. The type strain is CFS3442T (=NCTC 14921T=LMG 33162T).


Assuntos
Ácidos Graxos , Stenotrophomonas , Ácidos Graxos/química , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Hibridização de Ácido Nucleico , Composição de Bases , Técnicas de Tipagem Bacteriana , Hospitais
3.
Antimicrob Agents Chemother ; 68(3): e0086623, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38329347

RESUMO

L1-like metallo-ß-lactamases (MBLs) exhibit diversity and are highly conserved. Although the presence of the blaL1-like gene is known, the biochemical characteristics are unclear. This study aimed to characterize an L1-like MBL from Stenotrophomonas lactitubi. It showed 70.9-99.7% similarity to 50 L1-like amino acid sequences. The characteristic kinetic parameter was its high hydrolyzing efficiency for ampicillin and nitrocefin. Furthermore, L1-like from S. lactitubi was distinctly more susceptible to inhibition by EDTA than that to inhibition by 2,6-pyridinedicarboxylic acid.


Assuntos
Antibacterianos , beta-Lactamases , Antibacterianos/farmacologia , Antibacterianos/química , beta-Lactamases/metabolismo , Stenotrophomonas/genética , Sequência de Aminoácidos
4.
Mol Plant Pathol ; 25(1): e13412, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38279854

RESUMO

Stenotrophomonas rhizophila CFBP13503 is a seedborne commensal bacterial strain, which is efficiently transmitted to seedlings and can outcompete the phytopathogenic bacterium Xanthomonas campestris pv. campestris (Xcc8004). The type VI secretion system (T6SS), an interference contact-dependent mechanism, is a critical component of interbacterial competition. The involvement of the T6SS of S. rhizophila CFBP13503 in the inhibition of Xcc8004 growth and seed-to-seedling transmission was assessed. The T6SS cluster of S. rhizophila CFBP13503 and nine putative effectors were identified. Deletion of two T6SS structural genes, hcp and tssB, abolished the competitive advantage of S. rhizophila against Xcc8004 in vitro. The population sizes of these two bacterial species were monitored in seedlings after inoculation of radish seeds with mixtures of Xcc8004 and either S. rhizophila wild-type (wt) strain or isogenic hcp mutant. A significant decrease in the population size of Xcc8004 was observed during confrontation with the S. rhizophila wt in comparison with T6SS-deletion mutants in germinated seeds and seedlings. We found that the T6SS distribution among 835 genomes of the Stenotrophomonas genus is scarce. In contrast, in all available S. rhizophila genomes, T6SS clusters are widespread and mainly belong to the T6SS group i4. In conclusion, the T6SS of S. rhizophila CFBP13503 is involved in the antibiosis against Xcc8004 and reduces seedling transmission of Xcc8004 in radish. The distribution of this T6SS cluster in the S. rhizophila complex could make it possible to exploit these strains as biocontrol agents against X. campestris pv. campestris.


Assuntos
Raphanus , Sistemas de Secreção Tipo VI , Xanthomonas campestris , Plântula/microbiologia , Xanthomonas campestris/genética , Sementes/microbiologia , Stenotrophomonas/genética , Proteínas de Bactérias/genética
5.
World J Microbiol Biotechnol ; 40(1): 30, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38057391

RESUMO

Keratinases have drawn increasing attention in recent decades owing to their catalytic versatility and broad applications from agriculture to medicine. In the present study, we isolated a highly keratinolytic and fibrinolytic bacterium from the campus soil and named it Stenotrophomonas sp. LMY based on genetic information. To identify the potential keratinase genes, the genome sequence of the strain was obtained and analyzed. Sequence alignment and comparison revealed that the protein 1_737 (KerZJ) had the highest sequence homology to a reported keratinase KerBL. We recombinantly expressed KerZJ in Escherichia coli Origami™ (DE) pLysS and purified it to homogeneity. KerZJ showed the highest activity at 40 °C and pH 9.0, and metal ions exhibited no significant effects on its activity. Although reducing agents would break the disulfide bonds in KerZJ and reduce its activity, KerZJ still exhibited the ability to hydrolyze feather keratin in the presence of ß-ME. KerZJ could efficiently digest human prion proteins. In addition, KerZJ showed fibrinolytic activity on fibrin plates and effectively eliminated blood clots in a thrombosis mouse model without side effects. Our results suggest that KerZJ is a versatile keratinase with significant potential for keratin treatment, decontamination of prions, and fibrinolytic therapy.


Assuntos
Peptídeo Hidrolases , Stenotrophomonas , Animais , Camundongos , Humanos , Stenotrophomonas/genética , Stenotrophomonas/metabolismo , Peptídeo Hidrolases/metabolismo , Metais/metabolismo , Queratinas , Plumas/metabolismo , Concentração de Íons de Hidrogênio
6.
Bull Environ Contam Toxicol ; 112(1): 19, 2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38142453

RESUMO

Every year, human activities introduce large amounts of synthetic plastics into the environment. Decomposition of the plastic derivatives is very difficult and time consuming, so it is essential to eliminate these pollutants using different methods. Bioremediation, is suitable option, because of the low cost and environmentally safe. In this research, degradation of low-density polyethylene (LDPE) was investigated by two strains, isolated from Hamadan province (Iran) landfill soil. After identification by 16sr DNA primers, their abilities of polyethylene biodegradation were examined by Fourier transform infrared (FTIR), SEM and Gas Chromatography-Mass Spectrometry (GC-MS). Using media contain polyethylene) after and before addition of bacteria), toxicity test was conducted by measuring the germination index, root and hypocotyl length of Lactuca sativa seed. After three months, 10.15% ± 1.04 weight loss of LDPE achieved through strain Stenotrophomonas sp. degradation. Both strains had high biofilm formation capacity, confirmed by Electron microscope images and FTIR analysis. GC-MS confirmed the presence of the end-product of LDPE degradation (Pentacosane, Hexacosane, and Octadecane). Both, Stenotrophomonas sp. and Alcaligenaceae bacterium had significant detoxification ability. In media contain LDPE (without bacteria), decrease in the germination of lettuce seeds was observed.


Assuntos
Poluentes Ambientais , Polietileno , Humanos , Polietileno/química , Biodegradação Ambiental , Stenotrophomonas/metabolismo , Bactérias/metabolismo , Poluentes Ambientais/metabolismo , Plásticos
7.
mSphere ; 8(6): e0058423, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37975665

RESUMO

IMPORTANCE: Infections with the opportunistic pathogen Stenotrophomonas maltophilia complex can be fatal for immunocompromised patients. The mechanisms used by the bacterium to compete against other prokaryotes are not well understood. We found that the type VI secretion system (T6SS) allows S. maltophilia complex to eliminate other bacteria and contributes to the competitive fitness against a co-infecting isolate. The presence of T6SS genes in isolates across the globe highlights the importance of this apparatus as a weapon in the antibacterial arsenal of S. maltophilia complex. The T6SS may confer survival advantages to S. maltophilia complex isolates in polymicrobial communities in both environmental settings and during infections.


Assuntos
Stenotrophomonas maltophilia , Sistemas de Secreção Tipo VI , Humanos , Sistemas de Secreção Tipo VI/genética , Stenotrophomonas maltophilia/genética , Stenotrophomonas , Antibacterianos/farmacologia
8.
F1000Res ; 12: 1373, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38021406

RESUMO

Background: A culture of the green algae Chlamydomonas reinhardtii was accidentally contaminated with three different bacteria in our laboratory facilities. This contaminated alga culture showed increased algal biohydrogen production. These three bacteria were independently isolated. Methods: The chromosomic DNA of one of the isolated bacteria was extracted and sequenced using PacBio technology. Tentative genome annotation (RAST server) and phylogenetic trees analysis (TYGS server) were conducted. Diverse growth tests were assayed for the bacterium and for the alga-bacterium consortium. Results: Phylogenetic analysis indicates that the bacterium is a novel member of the Stenotrophomonas genus that has been termed in this work as S. goyi sp. nov. A fully sequenced genome (4,487,389 base pairs) and its tentative annotation (4,147 genes) are provided. The genome information suggests that S. goyi sp. nov. is unable to use sulfate and nitrate as sulfur and nitrogen sources, respectively. Growth tests have confirmed the dependence on the sulfur-containing amino acids methionine and cysteine. S. goyi sp. nov. and Chlamydomonas reinhardtii can establish a mutualistic relationship when cocultured together. Conclusions: S. goyi sp. nov. could be of interest for the design of biotechnological approaches based on the use of artificial microalgae-bacteria multispecies consortia that take advantage of the complementary metabolic capacities of their different microorganisms.


Assuntos
Chlamydomonas reinhardtii , Chlamydomonas reinhardtii/genética , Stenotrophomonas , Filogenia , Bactérias/genética , Enxofre/metabolismo
9.
Microb Pathog ; 185: 106403, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37879452

RESUMO

A common environmental bacteria called Stenotrophomonas maltophilia has become an organism responsible for significant nosocomial infection, mortality in immunocompromised patients, and significantly increasing morbidity and is challenging to treat due to the antibiotic resistance activity of the organism. and bacteriophage therapy is one of the promising treatments against the organism. In this research, we isolated, identified, and characterized Stenotrophomonas phage CM1 against S. maltophilia. Stenotrophomonas phage CM1 head was measured to have a diameter of around 224.25 nm and a tail length of about 159 nm. The phage was found to have noticeable elongated tail spikes around 125 nm in length, the Myoviridae family of viruses, which is categorized under the order Caudovirales. The ideal pH for growth was around 7, demonstrated good thermal stability when incubated at 37-60 °C for 30 min or 60 min, and phage infectivity decreased marginally after 30 min of incubation at 1-5% chloroform concentration. Phage was 3,19,518 base pairs long and had an averaged G + C composition of 43.9 %; 559 open-reading frames (ORFs) were found in the bacteriophage genome, in which 508 of them are hypothetical proteins, 22 of them are other known proteins, 29 of them are tRNAs, and one of them is restriction enzyme. A phylogenetic tree was reconstructed, demonstrating that CM1 shares a close evolutionary relationship with other Stenotrophomonas phages.


Assuntos
Bacteriófagos , Humanos , Bacteriófagos/genética , Stenotrophomonas/genética , Filogenia , Genoma Viral , Myoviridae/genética , Fases de Leitura Aberta
10.
Antimicrob Agents Chemother ; 67(9): e0067323, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37584548

RESUMO

L1 metallo-ß-lactamases produced by Stenotrophomonas maltophilia exhibit high diversity. Here, we characterized the genomes of Stenotrophomonas species harboring blaL1-like genes using publicly available genome sequences. Our findings provide evidence that Stenotrophomonas species with blaL1-like genes constitute a complex comprising many species with high genetic diversity, and similarities between blaL1-like genes are lower than those of the genome. This suggests that the diversity of blaL1-like is attributable to species diversity in Stenotrophomonas species harboring blaL1-like and the rapid evolutionary changes in blaL1-like genes.


Assuntos
Stenotrophomonas maltophilia , Stenotrophomonas , Stenotrophomonas/genética , beta-Lactamases/genética , Stenotrophomonas maltophilia/genética
11.
Sheng Wu Gong Cheng Xue Bao ; 39(4): 1314-1331, 2023 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-37154308

RESUMO

Stenotrophomonas species are non-fermentative Gram-negative bacteria that are widely distributed in environment and are highly resistant to numerous antibiotics. Thus, Stenotrophomonas serves as a reservoir of genes encoding antimicrobial resistance (AMR). The detection rate of Stenotrophomonas is rapidly increasing alongside their strengthening intrinsic ability to tolerate a variety of clinical antibiotics. This review illustrated the current genomics advances of antibiotic resistant Stenotrophomonas, highlighting the importance of precise identification and sequence editing. In addition, AMR diversity and transferability have been assessed by the developed bioinformatics tools. However, the working models of AMR in Stenotrophomonas are cryptic and urgently required to be determined. Comparative genomics is envisioned to facilitate the prevention and control of AMR, as well as to gain insights into bacterial adaptability and drug development.


Assuntos
Farmacorresistência Bacteriana , Stenotrophomonas , Stenotrophomonas/genética , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Genômica , Testes de Sensibilidade Microbiana
12.
J Hazard Mater ; 452: 131358, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37027916

RESUMO

Human activities have led to elevated levels of selenium (Se) in the environment, which poses a threat to ecosystems and human health. Stenotrophomonas sp. EGS12 (EGS12) has been identified as a potential candidate for the bioremediation of repair selenium-contaminated environment because of its ability to efficiently reduce Se(IV) to form selenium nanospheres (SeNPs). To better understand the molecular mechanism of EGS12 in response to Se(IV) stress, a combination of transmission electron microscopy (TEM), genome sequencing techniques, metabolomics and transcriptomics were employed. The results indicated that under 2 mM Se(IV) stress, 132 differential metabolites (DEMs) were identified, and they were significantly enriched in metabolic pathways such as glutathione metabolism and amino acid metabolism. Under the Se(IV) stress of 2 mM, 662 differential genes (DEGs) involved in heavy metal transport, stress response, and toxin synthesis were identified in EGS12. These findings suggest that EGS12 may respond to Se(IV) stress by engaging various mechanisms such as forming biofilms, repairing damaged cell walls/cell membranes, reducing Se(IV) translocation into cells, increasing Se(IV) efflux, multiplying Se(IV) reduction pathways and expelling SeNPs through cell lysis and vesicular transport. The study also discusses the potential of EGS12 to repair Se contamination alone and co-repair with Se-tolerant plants (e.g. Cardamine enshiensis). Our work provides new insights into microbial tolerance to heavy metals and offers valuable information for bio-remediation techniques on Se(IV) contamination.


Assuntos
Recuperação e Remediação Ambiental , Metais Pesados , Selênio , Humanos , Selênio/metabolismo , Stenotrophomonas/genética , Stenotrophomonas/metabolismo , Ecossistema
13.
Curr Microbiol ; 80(3): 93, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36729340

RESUMO

Stenotrophomonas maltophilia is a ubiquitous multidrug-resistant opportunistic pathogen commonly associated with nosocomial infections. The purpose of this study was to isolate and characterize extended-spectrum beta-lactamase (ESBL) producing bacteria from painted turtles (Chrysemys picta) living in the wild and captured in southeastern Wisconsin. Fecal samples from ten turtles were examined for ESBL producing bacteria after incubation on HardyCHROM™ ESBL agar. Two isolates were cultivated and identified by 16S rRNA gene sequencing and whole genome sequencing (WGS) as Stenotrophomonas sp. 9A and S. maltophilia 15A. They were multidrug-resistant, as determined by antibiotic susceptibility testing. Stenotrophomonas sp. 9A was found to produce an extended spectrum beta-lactamase (ESBL) and both isolates were found to be carbapenem-resistant. EDTA-modified carbapenem inactivation method (eCIM) and the modified carbapenem inactivation method (mCIM) tests were used to examine the carbapenemase production and the test results were negative. Through WGS several antimicrobial resistance genes were identified in S. maltophilia 15A. For example a chromosomal L1 ß-lactamase gene, which is known to hydrolyze carbapenems, a L2 ß-lactamase gene, genes for the efflux systems smeABC and smeDEF and the aminoglycosides resistance genes aac(6')-lz and aph(3')-llc were found. An L2 ß-lactamase gene in Stenotrophomonas sp. 9A was identified through WGS.


Assuntos
Farmacorresistência Bacteriana Múltipla , Stenotrophomonas , Tartarugas , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , beta-Lactamases/genética , Carbapenêmicos , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Stenotrophomonas/efeitos dos fármacos , Stenotrophomonas/genética , Tartarugas/microbiologia
14.
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
15.
Chemosphere ; 311(Pt 1): 137085, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36328316

RESUMO

TNT, or 2,4,6-trinitrotoluene, is a common explosive that can contaminate soil and groundwater in production sites, military training areas, and disposal locations. The compound is highly toxic; therefore, there is an urgent need to rehabilitate the impacted environments. Harnessing the microbial ability to biodegrade TNT into environmentally harmless compound(s) is one approach to remediating contaminated sites. In our study, we report on the genomic and metabolic ability of Stenotrophomonas strain SG1 to degrade TNT under aerobic and anaerobic conditions. The bacterial strain SG1 was first isolated as a contaminant from a culture of Diaphorobacter sp. strain DS2 over minimal media supplemented with TNT. The draft genome assembly of strain SG1 is ∼4.7 Mb and is distributed among 358 contigs. The homology search against the custom database of enzymes responsible for TNT biodegradation revealed the presence of three N-ethylmaleimide reductases (NemA) with a defined KEGG ortholog and KEGG pathway of TNT degradation. The presence of respiratory nitrate reductases has also been mapped, which supports denitrification under anaerobic conditions. Experimentally, the TNT transformation rate accelerated when carbon sources, such as sodium acetate, sodium citrate, sodium succinate, sucrose, and glucose (final concentration of 5 mM), were added. Citrate promoted the highest growth and TNT transformation ratio (88.35%) in 120 h. With the addition of 5 mM ammonium chloride, TNT completely disappeared in the citrate and sucrose-containing treatments in 120 h. However, higher biomass was obtained in the sucrose and glucose-containing treatments in 120 h. During incubation, the formation of amino dinitrotoluene isomers, dinitrotoluene isomers, trinitrobenzene, azoxy isomers, diaryl hydroxylamines, and corresponding secondary amines was confirmed by GC/MS and UPLC/MS. 2-Amino-4-nitrotoluene, 4-amino-2-nitrotoluene, and 2-amino-6-nitrotoluene were also identified in the culture supernatant by GC/MS. Under anaerobic conditions, TNT completely disappeared in the citrate and citrate plus nitrate treatments. Since the strain shows the ability to remove TNT, this research should be useful in basic research and practical applications for removing TNT from wastewater.


Assuntos
Trinitrotolueno , Anaerobiose , Stenotrophomonas , Biodegradação Ambiental , Citratos , Sacarose , Glucose
16.
Environ Res ; 220: 115093, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36574801

RESUMO

Uranium is well-known to have serious adverse effects on the ecological environment and human health. Bioremediation stands out among many remediation methods owing to its being economically feasible and environmentally friendly. This study reported a great promising strategy for eliminating uranium by Stenotrophomonas sp. CICC 23833 in the aquatic environment. The bacterium demonstrated excellent uranium adsorption capacity (qmax = 392.9 mg/g) because of the synergistic effect of surface adsorption and intracellular accumulation. Further analysis revealed that hydroxyl, carboxyl, phosphate groups and proteins of microorganisms were essential in uranium adsorption. Intracellular accumulation was closely related to cellular activity, and the efficiency of uranium processing by the permeabilized bacterial cells was significantly improved. In response to uranium stress, the bacterium was found to release multiple ions in conjunction with uranium adsorption, which facilitates the maintenance of bacterial life activities and the conversion of uranyl to precipitates. These above results indicated that Stenotrophomonas sp. Had great potential application value for the remediation of uranium.


Assuntos
Urânio , Humanos , Adsorção , Stenotrophomonas/metabolismo , Biodegradação Ambiental , Bactérias/metabolismo
17.
Sci Total Environ ; 858(Pt 2): 160030, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356742

RESUMO

Nowadays, metal pollution due to the huge release of toxic elements to the environment has become one of the world's biggest problems. Bioremediation is a promising tool for reducing the mobility and toxicity of these contaminants (e.g. selenium), being an efficient, environmentally friendly, and inexpensive strategy. The present study describes the capacity of Stenotrophomonas bentonitica to biotransform SeVI through enzymatic reduction and volatilization processes. HAADF-STEM analysis showed the bacterium to effectively reduce SeVI (200 mM) into intra- and extracellular crystalline Se0 nanorods, made mainly of two different Se allotropes: monoclinic (m-Se) and trigonal (t-Se). XAS analysis appears to indicate a Se crystallization process based on the biotransformation of amorphous Se0 into stable t-Se nanorods. In addition, results from headspace analysis by gas chromatography-mass spectometry (GC-MS) revealed the formation of methylated volatile Se species such as DMSe (dimethyl selenide), DMDSe (dimethyl diselenide), and DMSeS (dimethyl selenenyl sulphide). The biotransformation pathways and tolerance are remarkably different from those reported with this bacterium in the presence of SeIV. The formation of crystalline Se0 nanorods could have positive environmental implications (e.g. bioremediation) through the production of Se of lower toxicity and higher settleability with potential industrial applications.


Assuntos
Nanotubos , Compostos de Selênio , Selênio , Selênio/metabolismo , Volatilização , Stenotrophomonas/metabolismo
18.
Front Cell Infect Microbiol ; 13: 1325379, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268792

RESUMO

Introduction: Stenotrophomonas maltophilia complex (Smc) comprises opportunistic Gram-negative bacilli responsible for various nosocomial infections. Limited data exists concerning its evolutionary lineage, global prevalence and pathogenicity. Methods: We conducted an extensive genomic analysis on 734 Smc genomes, of which 90 were newly sequenced and isolated from different patients. The species composition and evolutionary relationships of Smc were examined using core protein sequence analysis. Pathogenicity evaluation was used by assays for swimming motility, biofilm formation and identification of virulence factors. The broth microdilution method was used to evaluate the drug resistance spectrum of clinical isolates. Results: Phylogenetic analyses delineated 24 species-level clades, dominated by S. maltophilia (42.8%), S. sepilia (13.6%) and S. geniculata (9.9%). Geographically, strains were primarily distributed in Europe (34.2%), Asia (33.7%) and North America (24.0%), with intricate global distribution patterns. Meanwhile, 154 virulence-associated genes and 46 antimicrobial resistance genes within Smc were identified. These genes encoded span various functions, including motility, adherence, toxin, RND antibiotic efflux pumps, beta-lactamases and aminoglycoside-modifying enzymes. Moreover, significant variations were indicated in swimming motility and biofilm-forming capability across the different species, with S. sepilia exhibiting superior levels of both traits. Additionally, no statistically significant discrepancy was detected among Smc species to other antibiotics, despite the fact that all S. geniculata isolates were resistant to Ceftazidime and much higher than other species. Conclusion: Our findings indicate the need to pay increased attention to other mainstream species of Smc besides S. maltophilia in order to better manage Smc-related infections and tailor effective treatment strategies.


Assuntos
Stenotrophomonas maltophilia , Stenotrophomonas , Humanos , Virulência/genética , Filogenia , Stenotrophomonas maltophilia/genética , Evolução Biológica , Antibacterianos/farmacologia
19.
Viruses ; 16(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38275953

RESUMO

Stenotrophomonas maltophilia was discovered as a soil bacterium associated with the rhizosphere. Later, S. maltophilia was found to be a multidrug-resistant hospital-associated pathogen. Lytic bacteriophages are prospective antimicrobials; therefore, there is a need for the isolation and characterization of new Stenotrophomonas phages. The phage StenM_174 was isolated from litter at a poultry farm using a clinical strain of S. maltophilia as the host. StenM_174 reproduced in a wide range of clinical and environmental strains of Stenotrophomonas, mainly S. maltophilia, and it had a podovirus morphotype. The length of the genomic sequence of StenM_174 was 42,956 bp, and it contained 52 putative genes. All genes were unidirectional, and 31 of them encoded proteins with predicted functions, while the remaining 21 were identified as hypothetical ones. Two tail spike proteins of StenM_174 were predicted using AlphaFold2 structural modeling. A comparative analysis of the genome shows that the Stenotrophomonas phage StenM_174, along with the phages Ponderosa, Pepon, Ptah, and TS-10, can be members of the new putative genus Ponderosavirus in the Autographiviridae family. In addition, the analyzed data suggest a new subfamily within this family.


Assuntos
Bacteriófagos , Caudovirales , Stenotrophomonas maltophilia , Stenotrophomonas/genética , Estudos Prospectivos , Caudovirales/genética , Stenotrophomonas maltophilia/genética , Genoma Viral
20.
Chinese Journal of Biotechnology ; (12): 1314-1331, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981140

RESUMO

Stenotrophomonas species are non-fermentative Gram-negative bacteria that are widely distributed in environment and are highly resistant to numerous antibiotics. Thus, Stenotrophomonas serves as a reservoir of genes encoding antimicrobial resistance (AMR). The detection rate of Stenotrophomonas is rapidly increasing alongside their strengthening intrinsic ability to tolerate a variety of clinical antibiotics. This review illustrated the current genomics advances of antibiotic resistant Stenotrophomonas, highlighting the importance of precise identification and sequence editing. In addition, AMR diversity and transferability have been assessed by the developed bioinformatics tools. However, the working models of AMR in Stenotrophomonas are cryptic and urgently required to be determined. Comparative genomics is envisioned to facilitate the prevention and control of AMR, as well as to gain insights into bacterial adaptability and drug development.


Assuntos
Stenotrophomonas/genética , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Genômica , Testes de Sensibilidade Microbiana
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