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MSphere May 2024is an opportunistic human and animal pathogen severely understudied. Here, we conducted the largest genomic epidemiological study on this pathogen to date. Our data...
UNLABELLED
is an opportunistic human and animal pathogen severely understudied. Here, we conducted the largest genomic epidemiological study on this pathogen to date. Our data show that this bacterium has spread globally. Also, we found that some human and non-human isolates are not well differentiated from one another, implying transmission between clinical and non-clinical, non-human settings. Remarkably, human but also some non-human isolates have clinically important antibiotic resistance genes, and some of these genes are located in plasmids. Given these results, we put forward that should be considered an emerging One Health problem. In this regard, future molecular epidemiological studies about this species will go beyond human isolates and will consider animal-, plant-, and water-associated environments.
IMPORTANCE
is the most well-known species from the genus . However, other much less studied species could be important opportunistic pathogens of animals, plants and humans. Here, we conducted the largest genomic epidemiological study of , which has been described as a source not only of human but also of animal infections. Our analyses show that this bacterium has spread globally and that, in some instances, human and non-human isolates are not well differentiated. Remarkably, some non-human isolates have important antibiotic resistance genes against important antibiotics used in human medicine. Based on our results, we propose that this pathogen must be considered an issue not only for humans but also for veterinary medicine.
Topics: Acinetobacter Infections; Humans; Acinetobacter; Animals; One Health; Genome, Bacterial; Anti-Bacterial Agents; Molecular Epidemiology; Communicable Diseases, Emerging; Drug Resistance, Bacterial; Plasmids; Genomics
PubMed: 38606973
DOI: 10.1128/msphere.00162-24 -
Microbiology Spectrum Apr 2024Tigecycline is an antibiotic of last resort for infections with carbapenem-resistant . Plasmids harboring variants of the tetracycline destructase gene promote rising...
UNLABELLED
Tigecycline is an antibiotic of last resort for infections with carbapenem-resistant . Plasmids harboring variants of the tetracycline destructase gene promote rising tigecycline resistance rates. We report the earliest observation of ) in a clinical strain predating tigecycline's commercialization, suggesting selective pressures other than tigecycline contributed to its emergence.
IMPORTANCE
We present the earliest observation of a ()-positive bacterial strain, predating by many years the earliest reports of this gene so far. This finding is significant as tigecycline is an antibiotic of last resort for carbapenem-resistant (CRAB), which the World Health Organization ranks as one of its top three critical priority pathogens, and () variants have become the most prevalent genes responsible for enabling CRAB to become tigecycline resistant. Moreover, the ()-positive strain we report is the first and only to be found that predates the commercialization of tigecycline, an antibiotic that was thought to have contributed to the emergence of this resistance gene. Understanding the factors contributing to the origin and spread of novel antibiotic resistance genes is crucial to addressing the major global public health issue, which is antimicrobial resistance.
Topics: Tigecycline; Microbial Sensitivity Tests; Anti-Bacterial Agents; Tetracycline; Plasmids; Carbapenems
PubMed: 38412527
DOI: 10.1128/spectrum.03327-23 -
Heliyon Feb 2024This study was aimed at using microcosm experiments to assess crude oil degradation efficiency of and isolated along Ghana's coast. Uncontaminated seawater from...
This study was aimed at using microcosm experiments to assess crude oil degradation efficiency of and isolated along Ghana's coast. Uncontaminated seawater from selected locations along the coast was used to isolate bacterial species by employing enrichment culture procedures with crude oil as the only carbon source. The isolates were identified by means of the extended direct colony transfer method of the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy (MALDI-TOF MS), as , and . Remediation tests showed that yielded degradation efficiencies of 27.59 %, 41.38 % and 57.47 %. Whereas efficiencies of 21.14 %, 32.18 % and 43.68 % were recorded by representing 15, 30 and 45 days respectively. Consortia of , and also yielded 32.18 %, 48.28 % and 62.07 % for the selected days respectively. Phylogenetic characterization using ClustalW and BLAST of sequences generated from the Oxford Nanopore Sequencing technique, showed that the Ghanaian isolates clustered with and species respectively. An analysis of the sequenced data for the 1394-bp portion of the 16S rRNA gene of the isolates revealed >99 % sequence identity with the isolates present on the GenBank database. The isolates of closest identity were and with accession numbers, NR_133958.1 and KJ147060.1 respectively. and isolated from Ghana's coast under pristine seawater conditions have therefore demonstrated their capacity to be used for the remediation of crude oil spills.
PubMed: 38318038
DOI: 10.1016/j.heliyon.2024.e24994 -
International Journal of Molecular... Jul 2023Metal-Organic Frameworks (MOFs) offer new ideas for the design of antibacterial materials because of their antibacterial properties, high porosity and specific surface...
Metal-Organic Frameworks (MOFs) offer new ideas for the design of antibacterial materials because of their antibacterial properties, high porosity and specific surface area, low toxicity and good biocompatibility compared with other nanomaterials. Herein, a novel antimicrobial nanomaterial, MIL-101(Fe)@ZnO, has been synthesized by hydrothermal synthesis and characterized by FTIR, UV-vis, ICP-OES, XRD, SEM, EDS and BET to show that the zinc ions are doped into the crystal lattice of MIL-101(Fe) to form a Fe-Zn bimetallic structure. MIL-101(Fe)@ZnO was found to be effective against a wide range of antibacterial materials including , , , , and . It has a significant antibacterial effect, weak cytotoxicity, high safety performance and good biocompatibility. Meanwhile, MIL-101(Fe)@ZnO was able to achieve antibacterial effects by causing cells to produce ROS, disrupting the cell membrane structure, and causing protein leakage and lipid preoxidation mechanisms. In conclusion, MIL-101(Fe)@ZnO is an easy-to-prepare antimicrobial nanomaterial with broad-spectrum bactericidal activity and low toxicity.
Topics: Zinc Oxide; Metal-Organic Frameworks; Nanoparticles; Anti-Bacterial Agents
PubMed: 37569611
DOI: 10.3390/ijms241512238 -
Journal of Laboratory Physicians Sep 2023species has become a leading cause of nosocomial infections in recent years. The aim of the study was to establish the usefulness of matrix-assisted laser...
species has become a leading cause of nosocomial infections in recent years. The aim of the study was to establish the usefulness of matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS) for the identification of species with respect to conventional biochemical methods and MicroScan WalkAway 96 Plus system and to compare the antibiotic susceptibility test results Kirby-Bauer disk diffusion method with MicroScan WalkAway 96 Plus automated identification and antimicrobial susceptibility testing system. The study sample comprised 100 clinical isolates of species. They were all identified using MALDI-TOF MS and compared with other two identification systems. Comparison of categorical variables by Fisher's exact test or Pearson's chi-square test was done. All statistical tools were two tailed, and a significant level < 0.05 was used. All statistical tests were performed using SPSS v22.0 (Armonk IBM Corp., New York, United States). Cohen's kappa coefficients were also calculated and used as applicable. MALDI-TOF MS revealed 92 , 2 , 3 , and 1 each was identified as , , and . There was moderate agreement between identification by MicroScan WalkAway and MALDI-TOF, and substantial agreement between conventional biochemical tests and MALDI-TOF. We found that there was a 100% categorical agreement with respect to susceptibility of aminoglycosides (amikacin, gentamicin, tobramycin) and cephalosporins (ceftazidime, cefepime, cefotaxime) between disk diffusion method and MicroScan WalkAway 96 Plus system. Total of 16 errors were observed. Although MALDI-TOF MS could be useful to identify but not other species in the genus, it is a rapid, reliable method and can be routinely used in clinical laboratories.
PubMed: 37564221
DOI: 10.1055/s-0042-1760401 -
Journal of Global Antimicrobial... Jun 2023Colistin-resistant Gram-negative pathogens have become a serious worldwide medical problem. This study was designed to reveal the effects of an intrinsic...
OBJECTIVES
Colistin-resistant Gram-negative pathogens have become a serious worldwide medical problem. This study was designed to reveal the effects of an intrinsic phosphoethanolamine transferase from Acinetobacter modestus on Enterobacterales.
METHODS
A strain of colistin-resistant A. modestus was isolated from a sample of nasal secretions taken in 2019 from a hospitalised pet cat in Japan. The whole genome was sequenced by next generation sequencing, and transformants of Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae harbouring the phosphoethanolamine transferase-encoding gene from A. modestus were constructed. Lipid A modification in E. coli transformants was analysed using electrospray ionization mass spectrometry.
RESULTS
Sequencing of the entire genome revealed that the isolate harboured a phosphoethanolamine transferase-encoding gene, eptA_AM, on its chromosome. Transformants of E. coli, K. pneumoniae, and E. cloacae harbouring both the promoter and eptA_AM gene from A. modestus had 32-fold, 8-fold, and 4-fold higher minimum inhibitory concentrations (MICs) for colistin, respectively, than transformants harbouring a control vector. The genetic environment surrounding eptA_AM in A. modestus was similar to that surrounding eptA_AM in Acinetobacter junii and Acinetobacter venetianus. Electrospray ionization mass spectrometry analysis revealed that EptA_AM modified lipid A in Enterobacterales.
CONCLUSION
This is the first report to describe the isolation of an A. modestus strain in Japan and show that its intrinsic phosphoethanolamine transferase, EptA_AM, contributes to colistin resistance in Enterobacterales and A. modestus.
Topics: Animals; Cats; Colistin; Escherichia coli; Lipid A; Ethanolaminephosphotransferase; Bacterial Proteins; Drug Resistance, Bacterial; Anti-Bacterial Agents; Klebsiella pneumoniae
PubMed: 36906175
DOI: 10.1016/j.jgar.2023.02.023 -
Microorganisms Feb 2023Waste oil pollution and the treatment of oily waste present a challenge, and the exploitation of microbial resources is a safe and efficient method to resolve these...
Waste oil pollution and the treatment of oily waste present a challenge, and the exploitation of microbial resources is a safe and efficient method to resolve these problems. Lipase-producing microorganisms can directly degrade waste oil and promote the degradation of oily waste and, therefore, have very significant research and application value. The isolation of efficient oil-degrading strains is of great practical significance in research into microbial remediation in oil-contaminated environments and for the enrichment of the microbial lipase resource library. In this study, WCO-9, an efficient oil-degrading bacterium, was isolated from an oil-contaminated soil using olive oil as the sole carbon source, and its enzyme activity of ρ-nitrophenyl decanoate (ρ-NPD) decomposition was 3000 U/L. The WCO-9 strain could degrade a variety of edible oils, and its degradation capability was significantly better than that of the control strain, ATCC 17908. Comparative pan-genome and lipid degradation pathway analyses indicated that isolated from the same environment shared a similar set of core genes and that the species accumulated more specific genes that facilitated resistance to environmental stresses under different environmental conditions. WCO-9 has accumulated a complete set of oil metabolism genes under a long-term oil-contamination environment, and the compact arrangement of abundant lipase and lipase chaperones has further strengthened the ability of the strain to survive in such environments. This is the main reason why WCO-9 is able to degrade oil significantly more effectively than ATCC 17908. In addition, WCO-9 possesses a specific lipase that is not found in homologous strains. In summary, WCO-9, with a complete triglyceride degradation pathway and the specific lipase gene, has great potential in environmental remediation and lipase for industry.
PubMed: 36838372
DOI: 10.3390/microorganisms11020407 -
Heliyon Feb 2023The utilization and improper use of crude oil can have irreparable damage on the environment and human populations. This study sought to isolate hydrocarbon utilizing...
The utilization and improper use of crude oil can have irreparable damage on the environment and human populations. This study sought to isolate hydrocarbon utilizing bacteria from 1% v/v pristine seawater and 1% v/v crude oil using enrichment culture techniques. Whole genome sequencing of DNA using the Oxford Nanopore sequencing technique with Fastq WIMP as the workflow at 3% abundance was undertaken. The results showed that the most abundant isolates identified using this technique at specific sampling sites were, (51.9%) (15.8%) (21.6%) (23.4%) (24.7%) (23.0%) (40.0%) and (14.2%). Cumulatively, the most abundant isolates in the 8 sampling sites were (17.91%), (11.68%) (7.68%) (7.67%) (3.40%) (3.10%). Spearman's rank correlation analysis to examine the strength of relationship between the physicochemical parameters and type of bacteria isolated, revealed that salinity (0.8046) and pH (0.7252) were the highest. Isolated bacteria from pristine seawater, especially have shown their capacity for bioremediating oil spill pollution in oceanic environments in Ghana.
PubMed: 36785818
DOI: 10.1016/j.heliyon.2023.e13075 -
Antibiotics (Basel, Switzerland) Nov 2022The increasing number of multidrug-resistant Gram-negative bacteria presents a serious threat to global health. However, colistin-resistant has rarely been reported. We...
The increasing number of multidrug-resistant Gram-negative bacteria presents a serious threat to global health. However, colistin-resistant has rarely been reported. We identified a colistin-resistant clinical isolate, AJ6079, in blood. The colony of AJ6079 presented a dry phenotype, and it was difficult to form a bacterial suspension, whilst transmission electron microscopy revealed that AJ6079 possessed a thick outer membrane. The phenotypic and genomic comparisons were conducted with one colistin-susceptible , which had the same antibiotic susceptibility profile except for colistin, and had the same KL25 capsule biosynthesis locus. The AJ6079 exhibited a slower growth rate, indicating that colistin-resistant possesses a higher fitness cost. The genome of AJ6079 had a G+C content of 38.7% and contained one 3,362,966 bp circular chromosome with no plasmid or mobile colistin resistance () gene. Comparative genomic analysis revealed that the AJ6079 contained several previously unreported point mutations in colistin-resistance-related genes involving amino acid substitutions in PmrB (N5K, G147C), LpxA (I107F, H131Y), and LpxD (F20I, K263R), which might be correlated with colistin resistance in . Further research is needed for verification as the genetic background was not exactly the same between the two isolates.
PubMed: 36551350
DOI: 10.3390/antibiotics11121693 -
Microbiology Spectrum Dec 2022New Delhi metallo-β-lactamase (NDM)-producing clinical strains in Acinetobacter spp. have been recently reported in many countries and have received considerable...
New Delhi metallo-β-lactamase (NDM)-producing clinical strains in Acinetobacter spp. have been recently reported in many countries and have received considerable attention. The vast majority of cases occur on conjugative plasmids, which play a vital role in disseminating . To characterize the conjugative plasmids bearing genes in Acinetobacter spp., we analyzed the variants of , conjugative transfer regions, genetic contexts of , and the phylogenetic pattern of the 62 predicted -positive plasmids, which were selected from 1,191 plasmids of Acinetobacter species from GenBank. We identified 30 conjugative plasmids from the 62 -harboring plasmids in Acinetobacter species, with the sites similar to plasmid pNDM-YR7 in our study, genes coding for relaxases of the MOB family, genes encoding type IV coupling proteins (T4CPs) of the TrwB/TraD subfamily, and VirB-like type IV secretion system (T4SS) gene clusters. The genome sizes of all 30 pNDM-YR7-like plasmids ranged from 39.36 kb to 49.65 kb, with a median size of 44.56 kb. The most common species of Acinetobacter containing the -positive conjugative plasmids was A. baumannii, followed by Acinetobacter lwoffii and Acinetobacter indicus. Notably, pNDM-YR7 is the first report on a -positive conjugative plasmid in Acinetobacter junii. Moreover, all 30 -positive conjugative plasmids in Acinetobacter species were found to contain genetic contexts with the structure IS--IS--. Our findings provide important insights into the phylogeny and evolution of -positive plasmids of Acinetobacter species and further address their role in acquiring and spreading genes in Acinetobacter species. Conjugative plasmids harboring the gene play a vital role in disseminating carbapenem resistance. In this study, we first report a conjugative plasmid, pNDM-YR7, in Acinetobacter junii. Based on the genomic characteristics of the -positive pNDM-YR7, we performed typing and comparative analysis of -positive plasmids using the 1,191 plasmids of Acinetobacter species available in the NCBI RefSeq database. We analyzed the characteristics of -positive plasmids, including the variants of , genetic features associated with , conjugative transfer regions, and the phylogenetic pattern of the -positive plasmids. All 30 -positive conjugative plasmids were found to contain an IS--IS-- region. This study provides novel insights into the phylogeny and evolution of -harboring conjugative plasmids and contributes to the repertoire of knowledge surrounding -positive plasmids in the genus Acinetobacter.
Topics: Phylogeny; Acinetobacter; Plasmids; beta-Lactamases; Anti-Bacterial Agents; Microbial Sensitivity Tests
PubMed: 36301090
DOI: 10.1128/spectrum.02102-22