-
Bioresource Technology Apr 2024This work aims at intensifying the simultaneous removal of nitrogen and phosphorus of an integrated aerobic granular sludge (AGS) - membrane bioreactor (MBR) by...
This work aims at intensifying the simultaneous removal of nitrogen and phosphorus of an integrated aerobic granular sludge (AGS) - membrane bioreactor (MBR) by Acinetobacter junii. After acclimation and enrichment in a sequencing batch reactor (SBR), Acinetobacter junii, a kind of denitrifying phosphate accumulating organism (DPAO), was successfully screened in the used SBR. Then it was verified to be capable of effectively enhancing the performance in the simultaneous removal of nitrogen and phosphorus of AGS-MBR. In the system, DPAO (Acinetobacter junii) mainly occurred in AGS, and the highest ratio even reached 22.8%, but its competitive advantages highly depend on the size of AGS. The presented results can cultivate AGS and enrich DPAO simultaneously to improve the removal of nitrogen and phosphorus of an AGS-MBR, which provide an environmentally friendly approach to upgrade traditional wastewater treatment processes.
Topics: Sewage; Phosphorus; Nitrogen; Phosphates; Bioreactors; Waste Disposal, Fluid; Acinetobacter
PubMed: 38395234
DOI: 10.1016/j.biortech.2024.130474 -
Journal of Applied Microbiology Apr 2019The aims of the study were to (i) isolate and characterize arsenic-tolerant bacterial strains, (ii) study the plant growth-promoting traits and (iii) explore their...
AIMS
The aims of the study were to (i) isolate and characterize arsenic-tolerant bacterial strains, (ii) study the plant growth-promoting traits and (iii) explore their bioremediation potential.
METHODS AND RESULTS
Indigenous arsenic hypertolerant bacterial isolates NM02 and NM03 were screened as they were capable of growing at 150 mmol l As (V) and 70 mmol l As (III). They were identified on the basis of morphological, physiological and biochemical parameter and 16sDNA sequence as Bacillus flexus and Acinetobacter junii respectively. Genomic DNA analysis for the investigation of ars operon revealed the presence of metalloregulatory arsC gene, suggesting their ability to detoxify arsenic. The analysis for siderophore, phosphate solubilization, indole acetic acid (IAA) and ACC deaminase highlighted the intrinsic plant growth-promoting rhizobacteria traits of both the bacterial strains. The energy dispersive spectroscopy analysis proved the potential of cellular arsenic sequestration within the strains. Moreover, Fourier-transform infrared spectra revealed the repositioning of the spectral bands in As presence, indicating the presence of those functional groups on the bacterial surface that is involved in As adsorption.
CONCLUSIONS
Our results indicate that bacterial strains NM02 and NM03 were identified as potent applicants for arsenic bioremediation and possess the ability to facilitate plant growth.
SIGNIFICANCE AND IMPACT OF THE STUDY
The bacterial strains are proficient in As detoxification and can be employed for arsenic bioremediation; a cost-effective and in situ remediation technique for the polluted soil.
Topics: Acinetobacter; Adaptation, Physiological; Arsenic; Bacillus; Bacterial Proteins; Biodegradation, Environmental; Plant Growth Regulators; RNA, Ribosomal, 16S; Soil Microbiology; Soil Pollutants
PubMed: 30556924
DOI: 10.1111/jam.14179 -
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 -
The Journal of Antimicrobial... Feb 2015
Topics: Acinetobacter; Acinetobacter calcoaceticus; Animals; Environmental Microbiology; Humans; Livestock; beta-Lactamases
PubMed: 25349061
DOI: 10.1093/jac/dku405 -
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 -
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 -
Surgical Infections Mar 2022
Topics: Acinetobacter; Bile Duct Neoplasms; Cholangitis; Humans; Klatskin Tumor; Stents
PubMed: 34668785
DOI: 10.1089/sur.2021.264 -
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 -
Journal of Infection and Chemotherapy :... Oct 2022Sphingobacterium is an aerobic, glucose non-fermenting, Gram-negative rod bacterium that has been isolated from soil, plants, food, and water sources, including in...
INTRODUCTION
Sphingobacterium is an aerobic, glucose non-fermenting, Gram-negative rod bacterium that has been isolated from soil, plants, food, and water sources, including in hospitals. Reports of systemic infections caused by Sphingobacterium multivorum (S. multivorum) are rare, and their clinical and microbiological characteristics remain unclear. Moreover, conventional microbiological methods have limited ability to identify S. multivorum. We report the first case of obstructive cholangitis with bacteremia caused by S. multivorum in a patient with gastric cancer.
CASE REPORT
A 68-year-old woman with advanced gastric cancer, hypertension, and hyperlipidemia was admitted with obstructive jaundice, and subsequently developed obstructive cholangitis during the hospital stay. S. multivorum were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S ribosomal RNA sequencing of the patient's blood samples. Based on the antibiotic susceptibility results of the isolates, cefepime was administered intravenously for 14 days, with good therapeutic outcomes.
CONCLUSIONS
S. multivorum infection is rare, and its microbiology and pathogenicity in humans is mostly unknown. Therefore, multiple diagnostic approaches should be used to identify S. multivorum, and antimicrobial therapy should be selected based on the in vitro susceptibility. This report provides clinicians with novel information on the clinical manifestations and diagnostic methods for an accurate diagnosis of S. multivorum.
Topics: Acinetobacter; Aged; Bacteremia; Cholangitis; Female; Humans; RNA, Ribosomal, 16S; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Sphingobacterium; Stomach Neoplasms
PubMed: 35718261
DOI: 10.1016/j.jiac.2022.06.005