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Journal of Microbiological Methods Oct 2018Providencia is an opportunistic human pathogen that belongs to the Enterobacteriaceae family. The bacterial cell surface O-antigen is one of the most structurally...
Providencia is an opportunistic human pathogen that belongs to the Enterobacteriaceae family. The bacterial cell surface O-antigen is one of the most structurally variable cell constituents and serves as a basis for serotyping gram-negative bacteria. In this work, the genomes of 12 Providencia strains were sequenced, and genes driving O-antigen biosynthesis were analyzed. The O-antigen-synthesizing genes of Providencia are located in the O-antigen gene cluster (OGC) between the cpxA and yibK genes. The gene functions predicted in silico agreed with the known O-antigen structures. All clusters were found to contain both wzx and wzy and exhibit a high degree of heterogeneity. Based on the sero-specific genes, we developed a molecular serotyping system to detect 23 serotypes (from the present and previous studies) for the first time. Five Proteus strains, five Morganella strains, five uropathogenic Escherichia coli (UPEC) strains and 32 Providencia strains with other serotypes were used to assess the specificity of our multiplexed Luminex-based array. Five serogroups (O3, O8, O19, O38 and O52 strains) were used to determine the sensitivity of the suspension array. The detection sensitivity was 0.1 ng genomic DNA, 10 CFU/ml in pure culture, or 10 CFU/ml in mock urine specimens. Furthermore, 29 publicly available Providencia genomes (which have not been serotyped) were analyzed, and 23 novel putative OGC types were identified. In total, we identified 35 new OGCs and developed a molecular serotyping system based on the sero-specific genes. The established classification system can support promising applications in basic research, clinical diagnosis, and epidemiological surveillance.
Topics: Computer Simulation; Genome, Bacterial; Multigene Family; Multiplex Polymerase Chain Reaction; O Antigens; Providencia; Sensitivity and Specificity; Sequence Analysis, DNA; Serogroup; Serotyping
PubMed: 30138644
DOI: 10.1016/j.mimet.2018.08.009 -
Biotechnology Reports (Amsterdam,... Sep 2022Crude oil contamination introduces multiple threats to human health and the environment, most of which are from toxic heavy metals. Heavy metals cause significant...
Crude oil contamination introduces multiple threats to human health and the environment, most of which are from toxic heavy metals. Heavy metals cause significant threats because of their persistence, toxicity, and bio-accumulation. Biomineralization, performed through many microbial processes, can lead to the immobilization of heavy metals in formed minerals. The potential of the microbially carbonate-induced precipitation (MICP) in removal by biomineralization of several heavy metals was investigated. A collection of diverse 11 bacterial strains exhibited ureolytic activity and tolerance to heavy metals when growing in Luria-Bertani (LB) and urea medium. Determination of the minimum inhibitory concentrations (MIC) revealed that heavy metal toxicity was arranged as Cd > Ni > Cr > Cu > Zn. Three hydrocarbon-degrading bacterial strains (two of and one of ) exhibited the highest tolerance (MIC > 5 mM) to Cu, Cr, Zn, and Ni, whereas Cd exerted significantly higher toxicity with MIC <1 mM. At all MICP conditions, different proportions of calcium carbonate (calcite) and calcium phosphate (brushite) were formed. strains (QZ5 and QZ9) exhibited the highest removal efficiency of Cr (100%), whereas strain (QZ2) showed 100% removal of Zn. Heavy metal complexes were found as well. Cd removal was evidenced by the formation of cadmium phosphate induced by bacterial activity. Our study confirmed that hydrocarbon-degrading ureolytic bacteria not only can tolerate heavy metal toxicity but also have the capability to co-precipitate heavy metals. These findings indicate an effective and novel biological approach to bioremediate petroleum hydrocarbons and immobilize multiple heavy metals with mineral formation. This is of high importance for ecological restoration via stabilization of soil and alleviation of heavy metal toxicity.
PubMed: 35755319
DOI: 10.1016/j.btre.2022.e00747 -
Infection and Drug Resistance 2023The coexistence of with other resistance determinants is rarely reported for . Therefore, this study investigates the phenotypic and genetic characteristics of a...
BACKGROUND
The coexistence of with other resistance determinants is rarely reported for . Therefore, this study investigates the phenotypic and genetic characteristics of a multidrug-resistant strain YQ150713.
METHODS
YQ150713 was identified as carrying . S1-pulsed-field gel electrophoresis (S1-PFGE), Southern blotting, and conjugation experiments were used to determine plasmid characteristics. An antimicrobial susceptibility test was conducted. The complete genomic sequence of YQ150713 was obtained using Illumina NovaSeq 6000 and Oxford nanopore platforms. To further characterize the phylogenetic structure of YQ150713, average nucleotide identity (ANI) and phylogenetic analyses were conducted.
RESULTS
The S1-PFGE, Southern blot, and conjugation assays have confirmed that the isolate YQ150713 contains the gene on a conjugative plasmid pYQ150713-NDM-1. Antimicrobial susceptibility testing has indicated that strain YQ150713 was resistant to various common antibiotics, except aztreonam and fosfomycin. Bioinformatics analysis has further shown that pYQ150713-NDM-1 was a novel plasmid with a size of 265,883 bp, and and were co-located on it. Phylogenetic analysis suggesting has spread widely throughout the world.
CONCLUSION
In this study, and were co-localized on a novel plasmid pYQ150713-NDM-1 with a horizontal transfer function. To reduce the risk of the dissemination of such isolates in clinical settings, more surveillance will be required in the future.
PubMed: 37601562
DOI: 10.2147/IDR.S418131 -
Food Technology and Biotechnology Mar 2022Shrimp shells contain chitin that can be further processed into acetylglucosamine, which has been extensively used to treat joint damage. has a strong chitinolytic...
RESEARCH BACKGROUND
Shrimp shells contain chitin that can be further processed into acetylglucosamine, which has been extensively used to treat joint damage. has a strong chitinolytic activity and may be utilized in the form of immobilized cells in repeated fermentation. Pumice is a porous and rigid stone that offers superior mechanical strength, making it suitable for immobilization.
EXPERIMENTAL APPROACH
In the research submerged fermentation with different pumice stone sizes and pumice stone/growth medium ratios (/) was carried out for 4 days at 37 °C and pH=7.0. The optimum pumice stone size and pumice stone/growth medium ratio (/) were used to determine the optimum fermentation cycle for the production of acetylglucosamine using immobilized .
RESULTS AND CONCLUSIONS
Pumice stones of 1.0 cm×1.0 cm×1.0 cm and pumice stone/growth medium ratio of 1:5 were found to be the optimum conditions for successful immobilization of (90.0±1.6) % cells and production of (331.4±7.3) g/L acetylglucosamine. The highest acetylglucosamine concentration of (323.0±2.5) g/L was obtained in the first fermentation cycle, which then decreased and remained stable throughout the last three cycles.
NOVELTY AND SCIENTIFIC CONTRIBUTION
, a strong chitinolytic bacterium previously isolated from rotten shrimp shells, was used for the first time in immobilized form to produce acetylglucosamine. The findings in this research showed the potential use of cells immobilized in pumice stone for continuous production of acetylglucosamine in repeated fermentation.
PubMed: 35440879
DOI: 10.17113/ftb.60.01.22.6994 -
Microbial Drug Resistance (Larchmont,... Jun 2022Concerns have been raised regarding co-selection for antibiotic resistance among bacteria exposed to antibiotics used as growth promoters for some livestock and poultry...
Concerns have been raised regarding co-selection for antibiotic resistance among bacteria exposed to antibiotics used as growth promoters for some livestock and poultry species. Tetracycline had been commonly used for this purpose worldwide, and its residue has been associated with selection of resistant bacteria in aquatic biofilms. This study aimed to determine the resistance profile, the existence of some beta-lactamases genes and the capacity to form biofilm of bacteria isolated from water samples previously exposed to tetracycline (20 mg/L). Thirty-seven tetracycline-resistant bacterial strains were identified as , , , , , , and . The highest percentage of resistance was for ampicillin (75.75%) and amoxicillin/clavulanic acid (66.66%) in the Gram-negative bacteria and an strain showed high resistance to vancomycin (minimum inhibitory concentration 250 μg/mL). Among the strains analyzed, 81.09% had multidrug resistance and eight Gram-negatives carried the gene. All strains were able to form biofilm and 43.23% were strong biofilm formers. This study suggests that resistant bacteria can be selected under selection pressure of tetracycline, and that these bacteria could contribute to the maintenance and spread of antimicrobial resistance in this environment.
Topics: Anti-Bacterial Agents; Biofilms; Drug Resistance, Microbial; Enterococcus faecium; Escherichia coli; Microbial Sensitivity Tests; Tetracycline
PubMed: 35325574
DOI: 10.1089/mdr.2021.0255 -
Journal of Hazardous Materials Feb 2021Bioremediation is commonly conducted by microbial consortia rather than individual species in natural environments. Biodegradation of dicarboximide fungicides in...
Bioremediation is commonly conducted by microbial consortia rather than individual species in natural environments. Biodegradation of dicarboximide fungicides in brunisolic soil were significantly enhanced by two bacterial cocultures of Providencia stuartii JD and Brevundimonas naejangsanensis J3. The cocultures degraded 98.42 %, 95.44 %, and 96.81 % of 50 mg/L dimethachlon, iprodione, and procymidone in liquid culture within 6 d respectively, whose efficiency was 1.23 and 1.26, 1.25 and 1.23, and 1.24 and 1.24 times of strains JD and J3, respectively. The cocultures could effectively degrade dimethachlon, iprodione and procymidone to simple products. Moreover, the cocultures immobilized in a charcoal-alginate-chitosan carrier obviously surpassed free cocultures in terms of degradability, stability and reusability. In the field brunisolic soils treated by immobilized cocultures, 96.74 % of 20.25 kg a.i./ha dimethachlon, 95.02 % of 7.50 kg a.i./ha iprodione and 96.27 % of 7.50 kg a.i./ha procymidone were degraded after 7 d, respectively. Moreover, the lower half-lifes (1.53, 1.59 and 1.57 d) by immobilized cocultures were observed, as compared to free cocultures (3.60, 4.03 and 3.92 d) and natural dissipation (21.33, 20.51 and 20.09 d). This study highlights that strains JD and J3 have significant synergetic degradation advantages in rapid bioremediation of dicarboximide fungicide contamination sites.
Topics: Biodegradation, Environmental; Caulobacteraceae; Coculture Techniques; Fungicides, Industrial; Providencia
PubMed: 33264954
DOI: 10.1016/j.jhazmat.2020.123888 -
Stroke Oct 2019
Review
Topics: Atrial Fibrillation; Catheter Ablation; Humans; Stroke; Treatment Outcome
PubMed: 31510894
DOI: 10.1161/STROKEAHA.119.026890 -
Transboundary and Emerging Diseases Sep 2022Providencia rettgeri has been recognized as a zoonotic pathogen of humans and aquaculture animals and has become a global public health concern. However, scarce...
Providencia rettgeri has been recognized as a zoonotic pathogen of humans and aquaculture animals and has become a global public health concern. However, scarce information is available on the characterization of pathogenic P. rettgeri from kuruma shrimp Marsupenaeus japonicus. In the present study, a P. rettgeri isolate (KM4) was confirmed as a causative agent of red leg disease in cultured M. japonicus, which showed a median lethal dose (LD ) value of 5.01 × 10 CFU·ml and had multiple resistances to aminoglycosides, sulfonamides, and tetracycline antimicrobials used in aquaculture. In addition, the whole genome of isolate KM4 was sequenced and found to consist of a single circular chromosome of 4,378,712 bp and a circular plasmid of 171,394 bp. The genome sequence analysis further revealed the presence of potential virulence and antibiotic resistance genes in isolate KM4, which probably rendered this isolate particularly virulent. To our knowledge, this is the first study to characterize P. rettgeri pathogens from kuruma shrimp infected with red leg disease. The findings of this study can provide novel insights into the presence and distribution of pathogenicity-associated genes in shrimp-pathogenic P. rettgeri.
Topics: Aminoglycosides; Animals; Genomics; Humans; Penaeidae; Providencia; Sulfonamides; Tetracyclines
PubMed: 35768955
DOI: 10.1111/tbed.14647 -
Frontiers in Microbiology 2022A novel chromosome-encoded aminoglycoside -nucleotidyltransferase AadA33 was identified in strain P13. The AadA33 shares the highest amino acid identity of 51.28% with...
A novel chromosome-encoded aminoglycoside -nucleotidyltransferase AadA33 was identified in strain P13. The AadA33 shares the highest amino acid identity of 51.28% with the function characterized AadA31. Antibiotic susceptibility testing and enzyme kinetics analysis revealed that the function of AadA33 is to mediate spectinomycin and streptomycin resistance. The recombinant strain harboring (pUCP20-/ DH5α) displayed >256- and 128-fold increases in the minimum inhibitory concentration levels to spectinomycin and streptomycin, respectively, compared with the control strains pUCP20/DH5α. Enzyme kinetic parameters manifested the substrate of AadA33 including spectinomycin and streptomycin, with / of 3.28 × 10 (M s) and 3.37 × 10 (M s), respectively. Bioinformatics analysis revealed its structural mechanism of antimicrobial resistance, genetic context, and phylogenetic relationship with other aminoglycoside -nucleotidyltransferases. This study of AadA33 contributed to understanding the function and resistance mechanism of aminoglycoside -nucleotidyltransferase.
PubMed: 36177473
DOI: 10.3389/fmicb.2022.990739 -
Frontiers in Microbiology 2022Laboratory adaptation process used in sterile insect technique (SIT) programs can exert a significant impact on the insect-gut microbiome relationship, which may...
Laboratory adaptation process used in sterile insect technique (SIT) programs can exert a significant impact on the insect-gut microbiome relationship, which may negatively impact the quality and performance of the fly. In the present study, changes in the gut microbiota that occur through laboratory adaptation of two populations were investigated: Vienna 8 genetic sexing strain (GSS), a long-established control line, and a wild population recently introduced to laboratory conditions. The bacterial profiles were studied for both strains using amplicon sequencing of the 16S rRNA V3-V4 hypervariable region in larvae and in the gastrointestinal tract of teneral (1 day) and adults (5 and 15 days) reared under laboratory conditions for 14 generations (F0-F13). Findings demonstrated the development of distinct bacterial communities across the generations with differences in the bacterial composition, suggesting a strong impact of laboratory adaptation on the fly bacteriome. Moreover, different bacterial profiles were observed between wild and Vienna 8 FD-GSS displaying different patterns between the developmental stages. Proteobacteria, mainly members of the family, represented the major component of the bacterial community followed by Firmicutes (mainly in Vienna 8 FD-GSS adults) and Chlamydiae. The distribution of these communities is dynamic across the generations and seems to be strain- and age-specific. In the Vienna 8 FD-GSS population, exhibited high relative abundance in the first three generations and decreased significantly later, while was relatively stable. In the wild population, was dominant across most of the generations, indicating that the wild population was more resistant to artificial rearing conditions compared with the Vienna 8 FD-GSS colony. Analysis of the core bacteriome revealed the presence of nine shared taxa between most of the examined medfly samples including , and . In addition, the operational taxonomic unit co-occurrence and mutual exclusion networks of the wild population indicated that most of the interactions were classified as co-presence, while in the Vienna 8 FD-GSS population, the number of mutual exclusions and co-presence interactions was equally distributed. Obtained results provided a thorough study of the dynamics of gut-associated bacteria during the laboratory adaptation of different populations, serving as guidance for the design of colonization protocols, improving the effectiveness of artificial rearing and the SIT application.
PubMed: 35847076
DOI: 10.3389/fmicb.2022.919760