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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 -
Frontiers in Microbiology 2016Biosurfactant producers are crucial for incremental oil production in microbial enhanced oil recovery (MEOR) processes. The isolation of biosurfactant-producing bacteria...
Biosurfactant producers are crucial for incremental oil production in microbial enhanced oil recovery (MEOR) processes. The isolation of biosurfactant-producing bacteria from oil reservoirs is important because they are considered suitable for the extreme conditions of the reservoir. In this work, a novel biosurfactant-producing strain BD was isolated from a reservoir to reduce surface tension and emulsify crude oil. The biosurfactants produced by the strain were purified and then identified via electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS). The biosurfactants generated by the strain were concluded to be rhamnolipids, the dominant rhamnolipids were CHO, CHO, and CHO. The optimal carbon source and nitrogen source for biomass and biosurfactant production were NaNO and soybean oil. The results showed that the content of acid components increased with the progress of crude oil biodegradation. A glass micromodel test demonstrated that the strain significantly increased oil recovery through interfacial tension reduction, wettability alteration and the mobility of microorganisms. In summary, the findings of this study indicate that the newly developed BD strain and its metabolites have great potential in MEOR.
PubMed: 27872613
DOI: 10.3389/fmicb.2016.01710 -
Genomics Data Dec 2014The genus Acinetobacter consists of 31 validly published species ubiquitously distributed in nature and primarily associated with nosocomial infection. We report the...
The genus Acinetobacter consists of 31 validly published species ubiquitously distributed in nature and primarily associated with nosocomial infection. We report the 3.5 Mb draft genome of the Acinetobacter junii strain MTCC 11364. The genome has a G + C content of 38.0% and includes 3 rRNA genes (5S, 23S, 16S) and 64 aminoacyl-tRNA synthetase genes.
PubMed: 26484056
DOI: 10.1016/j.gdata.2013.10.005 -
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 -
Microbiology Resource Announcements Aug 2021Acinetobacter junii INC8271 was isolated from a cancer patient with polymicrobial bacteremia after biliary stent placement. The complete genome sequence consisted of a...
Acinetobacter junii INC8271 was isolated from a cancer patient with polymicrobial bacteremia after biliary stent placement. The complete genome sequence consisted of a chromosome of 3,530,883 bp (GC content, 38.56%) with 3,377 genes, including those encoding 74 tRNAs and 18 rRNAs, and two intact prophage sequences. No antibiotic resistance genes were detected.
PubMed: 34410161
DOI: 10.1128/MRA.00604-21 -
3 Biotech Jul 2018Phosphate (PO) accumulation associated with bacteria contributes to efficient remediation of eutrophic waters and has attracted attention due to its low cost, high...
Phosphate (PO) accumulation associated with bacteria contributes to efficient remediation of eutrophic waters and has attracted attention due to its low cost, high removal efficiency and environmental friendliness. In the present study, we isolated six strains from sludge with high concentrations of chemical oxygen demand, total nitrogen and total phosphorus levels. Among them, strain LH4 exhibited the greatest PO removal ability. Strain LH4 is typical of based on physiological, biochemical, and molecular analyses and is a PO-accumulating organism (PAO) based on toluidine blue staining. The strain grew quickly when subjected to aerobic medium after pre-incubation under anaerobic condition, with a maximum OD of 1.429 after 8 h and PO removal efficiency of 99%. Our data also indicated that this strain preferred utilizing the carbon (C) sources sodium formate and sodium acetate and the nitrogen (N) sources NHCl and (NH)SO over other compounds. To achieve optimal PO removal efficiency, a C:N ratio of 5:1, inoculation concentration of 3%, solution pH of 6, incubation temperature of 30 °C, and shaking speed of 100 rpm were recommended for strain LH4. By incubating this strain with different concentrations of PO, we calculated that its relative PO removal capacity ranged from 0.67 to 3.84 mg L h, ranking in the top three among reported PAOs. Our study provided a new PO-accumulating bacterial strain that holds promise for remediating eutrophic waters, and its potential for large-scale use warrants further investigation.
PubMed: 30023145
DOI: 10.1007/s13205-018-1338-4 -
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 Global Antimicrobial... Dec 2020The aim of this study was to identify Acinetobacter spp. strains from paediatric patients, to determine their genetic relationship, to detect antibiotic resistance genes...
OBJECTIVES
The aim of this study was to identify Acinetobacter spp. strains from paediatric patients, to determine their genetic relationship, to detect antibiotic resistance genes and to evaluate the role of efflux pumps in antibiotic resistance.
METHODS
A total of 54 non-duplicate, non-consecutive Acinetobacter spp. isolates were collected from paediatric patients. Their genetic relationship, antibiotic resistance profile, efflux pump activity, antibiotic resistance genes and plasmid profile were determined.
RESULTS
The isolates were identified as 24 Acinetobacter haemolyticus, 24 Acinetobacter calcoaceticus-baumannii (Acb) complex and 1 strain each of Acinetobacter junii, Acinetobacter radioresistens, Acinetobacter indicus, Acinetobacter lwoffii, Acinetobacter ursingii and Acinetobacter venetianus. The 24 A. haemolyticus were considered genetically unrelated. One strain was resistant to carbapenems, two to cephalosporins, two to ciprofloxacin and sixteen to aminoglycosides. The antibiotic resistance genes bla (29%), bla (4%), bla (8%), bla (29%), bla (4%), aac(6')-Ig (38%) and the novel variants bla (13%), bla (75%), aac(6')-Iga (4%), aac(6')-Igb (13%) and aac(6')-Igc (42%) were detected. Among 24 Acb complex, 5 were multidrug-resistant, carbapenem-resistant strains carrying bla and bla; they were genetically related and had the same plasmid profile. Other species were susceptible. In some strains of A. haemolyticus and Acb complex, the role of RND efflux pumps was evidenced by a decrease in the MICs for cefotaxime, amikacin and ciprofloxacin in the presence of an efflux pump inhibitor.
CONCLUSIONS
This study identified isolates of A. haemolyticus carrying new β-lactamase variants and shows for the first time the contribution of efflux pumps to antibiotic resistance in this species.
Topics: Acinetobacter; Acinetobacter Infections; Acinetobacter baumannii; Child; Hospitals, Pediatric; Humans; Mexico
PubMed: 32916332
DOI: 10.1016/j.jgar.2020.08.014 -
Urology Case Reports Sep 2020is one of more than 50 different species belonging to the genus . This bacterium is rarely reported to cause human infections. Here we described a rare case of , which...
is one of more than 50 different species belonging to the genus . This bacterium is rarely reported to cause human infections. Here we described a rare case of , which grew in urine culture approximately one month after the patient was discharged from the hospital with antibiotics for a urinary tract infection, which caused left obstructing renal calculi requiring nephrostomy tube placement.
PubMed: 32322533
DOI: 10.1016/j.eucr.2020.101209 -
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