Publications

metabolic and stress responses of acinetobacter oleivorans dr1 during long-chain alkane degradation.	acinetobacter oleivorans dr1 can utilize c12 -c30 alkanes as a sole carbon source but not short-chain alkanes (c6 , c10 ). two copies of each alkb-, alma- and lada-type alkane hydroxylase (ah) are present in the genome of dr1 cells. expression and mutational analyses of ahs showed that alkb1 and alkb2 are the major ah-encoding genes under c12 -c30 , and the roles of other alma- and lada genes are negligible. our data suggested that alkb1 is responsible for long-chain alkane utilization (c24 -c26 ...	2017	28857443
inhibitory effect of taurine on biofilm formation during alkane degradation in acinetobacter oleivorans dr1.	taurine, 2-aminoethanesulfonate, is known to function as an antioxidant or membrane stabilizer in eukaryotic cells, but its role in bacteria has been poorly characterized. biofilm formation of acinetobacter oleivorans dr1 was significantly reduced by taurine only during alkane degradation, suggesting that taurine affects alkane-induced cell surface. structurally similar compounds harboring an amine group such as hypotaurine or ethylenediamine have a similar effect, which was not observed with su ...	2017	28620784
characterization and degradation potential of diesel-degrading bacterial strains for application in bioremediation.	bioremediation of polluted soils is a promising technique with low environmental impact, which uses soil organisms to degrade soil contaminants. in this study, 19 bacterial strains isolated from a diesel-contaminated soil were screened for diesel-degrading potential, biosurfactant production, and biofilm formation abilities, all desirable characteristics when selecting strains for re-inoculation into hydrocarbon-contaminated soils. diesel degradation rates were determined in vitro in minimal med ...	2017	28598213
[influences of abar gene on biofilm formation of acinetobacter baumannii].	objective: to detect drug-resistant phenotype and abar gene of acinetobacter baumannii (ab) and investigate influences of abar gene on biofilm formation of ab. methods: from february to july 2014, 159 strains ab were collected from department of clinical microbiology of ruijin hospital of school of medicine of shanghai jiaotong university and numbered starting from 1 according time when they were collected. (1) the above-mentioned 159 strains of ab were identified by detecting gene sequence of 1 ...	2017	28427132
lineage-specific soxr-mediated regulation of an endoribonuclease protects non-enteric bacteria from redox-active compounds.	bacteria use redox-sensitive transcription factors to coordinate responses to redox stress. the [2fe-2s] cluster-containing transcription factor soxr is particularly tuned to protect cells against redox-active compounds (racs). in enteric bacteria, soxr is paired with a second transcription factor, soxs, that activates downstream effectors. however, soxs is absent in non-enteric bacteria, raising questions as to how soxr functions. here, we first show that soxr of acinetobacter oleivorans displa ...	2017	27895125
isolation and characterization of fipronil degrading acinetobacter calcoaceticus and acinetobacter oleivorans from rhizospheric zone of zea mays.	an enrichment culture technique was used for the isolation of bacteria capable of utilizing fipronil as a sole source of carbon and energy. based on morphological, biochemical characteristics and phylogenetic analysis of 16s rrna sequence, the bacterial strains were identified as acinetobacter calcoaceticus and acinetobacter oleivorans. biodegradation experiments were conducted in loamy sand soil samples fortified with fipronil (50 µg kg(-1)) and inoculated with acinetobacter sp. cells (45 × 10( ...	2016	27084098
endogenous hydrogen peroxide increases biofilm formation by inducing exopolysaccharide production in acinetobacter oleivorans dr1.	in this study, we investigated differentially expressed proteins in acinetobacter oleivorans cells during planktonic and biofilm growth by using 2-dimensional gel electrophoresis combined with matrix-assisted laser desorption time-of-flight mass spectrometry. we focused on the role of oxidative stress resistance during biofilm formation using mutants defective in alkyl hydroperoxide reductase (ahpc) because its production in aged biofilms was enhanced compared to that in planktonic cells. result ...	2016	26884212
identification of soil microbes capable of utilizing cellobiosan.	approximately 100 million tons of anhydrosugars, such as levoglucosan and cellobiosan, are produced through biomass burning every year. these sugars are also produced through fast pyrolysis, the controlled thermal depolymerization of biomass. while the microbial pathways associated with levoglucosan utilization have been characterized, there is little known about cellobiosan utilization. here we describe the isolation and characterization of six cellobiosan-utilizing microbes from soil samples. ...	2016	26872347
molecular mechanism involved in the response to hydrogen peroxide stress in acinetobacter oleivorans dr1.	two-dimensional gel electrophoresis was conducted to investigate the effect of h2o2 on whole protein expression in acinetobacter oleivorans dr1. functional classification of 13 upregulated proteins using maldi-tof mass spectrometry showed relationships with oxidative stress, energy production and conversion, nucleotide and amino acid metabolism, membrane-related, ion transport, and chaperone-related functions. alignment of oxyr-binding regions from pseudomonas aeruginosa and escherichia coli wit ...	2015	26298700
molecular mechanisms of enhanced bacterial growth on hexadecane with red clay.	red clay was previously used to enhance bioremediation of diesel-contaminated soil. it was speculated that the enhanced degradation of diesel was due to increased bacterial growth. in this study, we selected acinetobacter oleivorans dr1, a soil-borne degrader of diesel and alkanes, as a model bacterium and performed transcriptional analysis using rna sequencing to investigate the cellular response during hexadecane utilization and the mechanism by which red clay promotes hexadecane degradation. ...	2015	25956940
draft genome sequence of acinetobacter oleivorans pf1, a diesel-degrading and plant-growth-promoting endophytic strain isolated from poplar trees growing on a diesel-contaminated plume.	we report the 3.7-mb draft genome of acinetobacter oleivorans strain pf1, a hydrocarbonoclastic gram-negative bacterium in the class gammaproteobacteria, isolated from poplar trees growing on a diesel-contaminated plume at the ford motor company site in genk, belgium. strain pf1 is a potent plant-growth promoter, useful for diesel fuel phytoremediation applications.	2015	25657268
global transcriptome and physiological responses of acinetobacter oleivorans dr1 exposed to distinct classes of antibiotics.	the effects of antibiotics on environment-originated nonpathogenic acinetobacter species have been poorly explored. to understand the antibiotic-resistance mechanisms that function in nonpathogenic acinetobacter species, we used an rna-sequencing (rna-seq) technique to perform global gene-expression profiling of soil-borne acinetobacter oleivorans dr1 after exposing the bacteria to 4 classes of antibiotics (ampicillin, amp; kanamycin, km; tetracycline, tc; norfloxacin, nor). interestingly, the w ...	2014	25330344
plasmid-encoded tetracycline efflux pump protein alters bacterial stress responses and ecological fitness of acinetobacter oleivorans.	acquisition of the extracellular tetracycline (tc) resistance plasmid past2 affected host gene expression and phenotype in the oil-degrading soil bacterium, acinetobacter oleivorans dr1. whole-transcriptome profiling of dr1 cells harboring past2 revealed that all the plasmid genes were highly expressed under tc conditions, and the expression levels of many host chromosomal genes were modulated by the presence of past2. the host energy burden imposed by replication of past2 led to (i) lowered atp ...	2014	25229538
indole inhibition of n-acylated homoserine lactone-mediated quorum signalling is widespread in gram-negative bacteria.	the luxi/r quorum-sensing system and its associated n-acylated homoserine lactone (ahl) signal is widespread among gram-negative bacteria. although inhibition by indole of ahl quorum signalling in pseudomonas aeruginosa and acinetobacter oleivorans has been reported previously, it has not been documented among other species. here, we show that co-culture with wild-type escherichia coli, but not with e. coli tnaa mutants that lack tryptophanase and as a result do not produce indole, inhibits ahl- ...	2014	25165125
effect of red clay on diesel bioremediation and soil bacterial community.	red clay is a type of soil, the red color of which results from the presence of iron oxide. it is considered an eco-friendly material, with many industrial, cosmetic, and architectural uses. a patented method was applied to red clay in order to change its chemical composition and mineral bioavailability. the resulting product was designated processed red clay. this study evaluates the novel use of red clay and processed red clay as biostimulation agents in diesel-contaminated soils. diesel biode ...	2014	24743885
tetr repressor-based bioreporters for the detection of doxycycline using escherichia coli and acinetobacter oleivorans.	tetracycline (tc)-sensing bioreporters using green fluorescent protein (gfp) were generated in escherichia coli and solvent-tolerant acinetobacter oleivorans. a tc-inducible promoter, teth promoter, and a tetr repressor of the past2 plasmid recovered from sludge were used to construct plasmid-based and chromosome-based bioreporters. two host plasmids with a broad range, prk415 and pbbr1mcs2, and three randomly chosen chromosomal sites were used to create the reporter strains. although the copy n ...	2014	24504461
previously undescribed plasmids recovered from activated sludge confer tetracycline resistance and phenotypic changes to acinetobacter oleivorans dr1.	we used culture-dependent and culture-independent methods to extract previously undescribed plasmids harboring tetracycline (tc) resistance genes from activated sludge. the extracted plasmids were transformed into naturally competent acinetobacter oleivorans dr1 to recover a non-escherichia coli-based plasmid. the transformed cells showed 80-100-fold higher tc resistance than the wild-type strain. restriction length polymorphism performed using 30 transformed cells showed four different types of ...	2014	24337108
indole inhibits bacterial quorum sensing signal transmission by interfering with quorum sensing regulator folding.	quorum sensing (qs)-dependent biofilm formation and motility were controlled by aqsr in acinetobacter oleivorans dr1. qs-controlled phenotypes appeared to be inhibited by indole and the aqsr mutant had the same phenotypes. we demonstrated that the turnover rate of aqsr became more rapid without the n-acylhomoserine lactone (ahl) signal, and that indole could increase the expression of many protease and chaperone proteins. the addition of exogenous indole decreased the expression of two aqsr-targ ...	2013	24025605
insight into norfloxacin resistance of acinetobacter oleivorans dr1: target gene mutation, persister, and rna-seq analyses.	antibiotic resistance of soilborne acinetobacter species has been poorly explored. in this study, norfloxacin resistance of a soil bacterium, acinetobacter oleivorans dr1, was investigated. the frequencies of mutant appearance of all tested non-pathogenic acinetobacter strains were lower than those of pathogenic strains under minimum inhibitory concentration (mic). when the quinolone-resistance-determining region of the gyra gene was examined, only one mutant (his78asn) out of 10 resistant varia ...	2013	23928845
identification and characterization of genes regulated by aqsr, a luxr-type regulator in acinetobacter oleivorans dr1.	the complete genome of acinetobacter oleivorans dr1 contains aqsr and aqsi genes, which are luxr and luxi homolog, respectively. in a previous study, we demonstrated that quorum sensing (qs) signals play an important role in biofilm formation and hexadecane biodegradation. however, the regulation of genes controlled by the qs system in dr1 remains unexplored. we constructed an aqsr mutant and performed rna sequencing analysis to understand the qs system. a total of 353 genes were differentially ...	2013	23749119
Complexity of cell-cell interactions between Pseudomonas sp. AS1 and Acinetobacter oleivorans DR1: metabolic commensalism, biofilm formation and quorum quenching.	Acinetobacter oleivorans DR1 lacks an upper pathway for naphthalene degradation and cannot grow using naphthalene as sole carbon source; however, it is capable of growing under naphthalene-amended conditions in the presence of naphthalene-degrading Pseudomonas sp. AS1. (1)H-NMR spectroscopy, high-performance liquid chromatography and gene expression analyses showed that salicylate is a major secreted metabolic intermediate during naphthalene degradation by strain AS1 and that, in turn, it suppor ...	2011	22202171
Comparative genomic analysis of Acinetobacter oleivorans DR1 to determine strain-specific genomic regions and gentisate biodegradation.	The comparative genomics of Acinetobacter oleivorans DR1 assayed with A. baylyi ADP1, A. calcoaceticus PHEA-2, and A. baumannii ATCC 17978 revealed that the incorporation of phage-related genomic regions and the absence of transposable elements have contributed to the large size (4.15 Mb) of the DR1 genome. A horizontally transferred genomic region and a higher proportion of transcriptional regulator- and signal peptide-coding genes were identified as characteristics of the DR1 genome. Incomplet ...	2011	21856821
detection of genetically modified microorganisms in soil using the most-probable-number method with multiplex pcr and dna dot blot.	the principal objective of this study was to detect genetically modified microorganisms (gmms) that might be accidentally released into the environment from laboratories. two methods [plate counting and most-probable-number (mpn)] coupled with either multiplex pcr or dna dot blots were compared using genetically modified escherichia coli, pseudomonas putida, and acinetobacter oleivorans harboring an antibiotic-resistance gene with additional gfp and lacz genes as markers. alignments of sequences ...	2011	21810467
physiological and metabolic responses for hexadecane degradation in acinetobacter oleivorans dr1.	the hexadecane degradation of acinetobacter oleivorans dr1 was evaluated with changes in temperature and ionic salt contents. hexadecane degradation of strain dr1 was reduced markedly by the presence of sodium chloride (but not potassium chloride). high temperature (37°c) was also shown to inhibit the motility, biofilm formation, and hexadecane biodégradation. the biofilm formation of strain dr1 on the oil-water interface might prove to be a critical physiological feature for the degradation of ...	2011	21538240
acinetobacter oleivorans sp. nov. is capable of adhering to and growing on diesel-oil.	a diesel-oil and n-hexadecane-degrading novel bacterial strain, designated dr1(t), was isolated from a rice paddy in deok-so, south korea. the strain dr1(t) cells were gram-negative, aerobic coccobacilli, and grew at 20-37°c with the optimal temperature of 30°c, and an optimal ph of 6-8. interestingly, strain dr1(t) was highly motile (swimming and swarming motility) using its fimbriae, and generated n-acyl homoserine lactones as quorum-sensing signals. the predominant respiratory quinone as iden ...	2011	21369976