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activities of beta-lactams against acinetobacter genospecies as determined by agar dilution and e-test mic methods.the agar dilution mic method was used to test activities of ticarcillin, ticarcillin-clavulanate, amoxicillin, amoxicillin-clavulanate, ampicillin, ampicillin-sulbactam, piperacillin, piperacillin-tazobactam, inhibitors alone, ceftazidime, and imipenem against 237 acinetobacter genospecies. a total of 93.2% of strains were beta-lactamase positive by the chromogenic cephalosporin method. overall, ampicillin-sulbactam was the most active combination against all strains (mic at which 50% of the iso ...19979087486
phylogenetic relationship of the twenty-one dna groups of the genus acinetobacter as revealed by 16s ribosomal dna sequence analysis.the inter- and intrageneric relationships of members of the genus acinetobacter were investigated by performing a comparative sequence analysis of pcr-amplified 16s ribosomal dnas (rdnas) from 21 strains representing all of the dna groups that have been described. phylogenetic treeing confirmed that acinetobacter spp. form a coherent cluster within the gamma subdivision of the class proteobacteria that includes strains with overall levels of 16s rdna sequence similarity of more than 94%. the ana ...19979226915
structure--function studies of the recombinant protein bioemulsifier alna.acinetobacter radioresistens ka53 produces an extracellular bioemulsifier, referred to as alasan. the surface active component of alasan is a 35.77 kda protein alna. although alna and the escherichia coli outer membrane protein a (ompa) have a high amino acid sequence homology, e. coli ompa has no emulsifying activity. comparison of the amino acid sequences of alna and e. coli ompa revealed four hydrophobic regions in alna that were absent in e. coli ompa. deletions and substitutions (with the h ...200212030851
cloning and characterization of two catechol 1,2-dioxygenase genes from acinetobacter radioresistens s13.two novel catechol 1,2-dioxygenase (c 1,2-o) genes have been isolated from an acinetobacter radioresistens strain that grows on phenol or benzoate as sole carbon and energy source. designated as cata(a) and cata(b), they encode proteins composed of 314 and 306 amino acids, whose deduced sequences indicate that they have approximately 53% identity, whereas their nh2-terminal and cooh-terminal regions have no sequences in common. this may explain their different thermal and ph stability. polyclona ...200211900265
community-acquired acinetobacter radioresistens bacteremia in an hiv-positive patient.we describe the first case of community-acquired bacteremia caused by acinetobacter radioresistens; the patient was a 32-year-old hiv-positive neutropenic woman. ambiguous gram staining and poor biochemical reactivity of blood culture isolates misguided early diagnosis and therapy. bacterial identification was based on 16s rdna sequence analysis. a. radioresistens can be considered as a cause of opportunistic infection in immunodeficient patients.200111747736
the active component of the bioemulsifier alasan from acinetobacter radioresistens ka53 is an ompa-like protein.the bioemulsifier of acinetobacter radioresistens ka53, referred to as alasan, is a high-molecular-weight complex of polysaccharide and protein. recently, one of the alasan proteins, with an apparent molecular mass of 45 kda, was purified and shown to constitute most of the emulsifying activity. the n-terminal sequence of the 45-kda protein showed high homology to an ompa-like protein from acinetobacter spp. in the research described here the gene coding for the 45-kda protein was cloned, sequen ...200211741856
the catechol 1,2 dioxygenase system of acinetobacter radioresistens: isoenzymes, inductors and gene localisation.two different isozymes (iso a and iso b) of catechol 1,2 dioxygenase (c1,2o) were isolated from cultures of a. radioresistens grown in two different media, containing phenol and benzoate respectively. in the phenol medium the bacteria expressed about 90% of iso a, whereas in the benzoate medium the iso a/iso b ratio was 40:60. the two proteins have different molecular masses, isoelectric points and n-terminal sequences that are not consistent with simple post-translational modifications. further ...200111592407
media containing aromatic compounds induce peculiar proteins in acinetobacter radioresistens, as revealed by proteome analysis.an acinetobacter radioresistens strain able to grow on phenol or benzoate as sole carbon and energy source through the beta-ketoadipate pathway was isolated in our laboratories. in previous research, we found a different expression of catechol-1,2-dioxygenase isoenzymes (c-1,2-o) depending on the growth substrate (phenol or benzoate). in the present study, we used proteome techniques to extend our investigation to other enzymes involved in the aromatic degradation pathway. since the first nontox ...200111425226
purification and catalytic properties of two catechol 1,2-dioxygenase isozymes from benzoate-grown cells of acinetobacter radioresistens.two catechol 1,2-dioxygenase (c1,2o) isozymes (isoa and isob) have been purified to homogeneity from a strain of acinetobacter radioresistens grown on benzoate as the sole carbon and energy source. isoa and isob are both homodimers composed of a single type of subunit with molecular mass of 38,600 and 37,700, da respectively. in conditions of low ionic strength, isoa can aggregate as a trimer, in contrast to isob, which maintains the dimeric structure, as also supported by the kinetic parameters ...200011307956
horizontal transfer of an exopolymer complex from one bacterial species to another.alasan, the exocellular polymeric emulsifier produced by acinetobacter radioresistens ka53 was shown to bind to the surface of sphingomonas paucimobilis epa505 and acinetobacter calcoaceticus rag-1. the presence of alasan on the surface of s. paucimobilis epa505 and a. calcoaceticus rag-1 caused a decrease in their cell-surface hydrophobicities. binding was proportional to the concentration of recipient cells and input alasan. at the highest concentration of a. calcoaceticus rag-1 (4 x 10(9) ml( ...200011234924
emulsifying activities of purified alasan proteins from acinetobacter radioresistens ka53.the bioemulsifier of acinetobacter radioresistens ka53, referred to as alasan, is a high-molecular-weight complex of polysaccharide and protein. the emulsifying activity of the purified polysaccharide (apo-alasan) is very low. three of the alasan proteins were purified by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis and had apparent molecular masses of 16, 31, and 45 kda. emulsification assays using the isolated alasan proteins demonstrated that the active components of ...200111229898
lipase production by acinetobacter radioresistens in the presence of a nonwoven fabric.lipase production by acinetobacter radioresistens was performed in a 2-l tank fermentor equipped with a nonwoven fabric, which was made of nylon 6 fiber and coated with a hydrophobic acrylic resin. the fermentation medium contained 2% (v/v) n-hexadecane as the carbon source. the use of the nonwoven fabric was intended for the dispersion of hydrocarbons; thus, the contact surface for the cells to assimilate n-hexadecane can be increased without using emulsifiers. the formation of lipase was found ...199910514262
phenol hydroxylase from acinetobacter radioresistens is a multicomponent enzyme. purification and characterization of the reductase moiety.this paper reports the isolation and characterization of phenol hydroxylase (ph) from a strain belonging to the acinetobacter genus. an acinetobacter radioresistens culture, grown on phenol as the only carbon and energy source, produced a multicomponent enzyme system, located in the cytoplasm and inducible by the substrate, that is responsible for phenol conversion into catechol. because of the wide diffusion of phenol as a contaminant, the present work represents an initial step towards the bio ...199910504385
intraspecific differences in bacterial responses to modelled reduced gravity.bacteria are important residents of water systems, including those of space stations which feature specific environmental conditions, such as lowered effects of gravity. the purpose of this study was to compare responses with modelled reduced gravity of space station, water system bacterial isolates with other isolates of the same species.200515836494
semicontinuous production of lipase by acinetobacter radioresistens in presence of nonwoven fabric.the effect of a hydrophobic nonwoven fabric on the lipase production by acinetobacter radioresistens was investigated with semicontinuous culture. the fermentation medium contained n-hexadecane as the carbon source. the nonwoven fabric was made from nylon 6 and coated with an acrylic resin. equipping the nonwoven fabric around the baffles of a 2.5-l agitated fermentor could provide a fine dispersion of n-hexadecane, thus enhancing lipase production. the improvement on lipase yield by using the n ...200010949688
enhancement of solubilization and biodegradation of polyaromatic hydrocarbons by the bioemulsifier alasan.alasan, a high-molecular-weight bioemulsifier complex of an anionic polysaccharide and proteins that is produced by acinetobacter radioresistens ka53 (s. navon-venezia, z. zosim, a. gottlieb, r. legmann, s. carmeli, e. z. ron, and e. rosenberg, appl. environ. microbiol. 61:3240-3244, 1995), enhanced the aqueous solubility and biodegradation rates of polyaromatic hydrocarbons (pahs). in the presence of 500 microg of alasan ml-1, the apparent aqueous solubilities of phenanthrene, fluoranthene, and ...199910347063
effect of oxygen transfer on lipase production by acinetobacter radioresistens.the influence of oxygen on alkaline lipase production by acinetobacter radioresistens was studied under two operating modes: controlled dissolved oxygen (do) concentration and controlled aeration rate. compared with cell growth, the lipase production depended more extensively on oxygen. the intrinsic factor determining cell growth and lipase production was oxygen transfer rate (otr) rather than do concentration. improvements in otr, either by aeration or agitation, resulted in an increase in lip ...199910099542
production of acinetobacter radioresistens lipase with repeated batch culture in presence of nonwoven fabric.cultivation of acinetobacter radioresistens on n-hexadecane for lipase production was investigated with repeated batch culture in the presence of a hydrophobic nonwoven fabric. lipase production followed the growth-associated model, and the repeated batch culture could achieve both high enzyme yield and increased volumetric productivity. the fabric was shown to be able to disperse n-hexadecane, to adsorb the unused hydrocarbon, and to retain bioemulsifiers excreted from the cells; therefore, it ...200111668456
exceptional desiccation tolerance of acinetobacter radioresistens.the taxonomy of the genus acinetobacter, which includes several important nosocomial pathogens, has been confused due to a lack of discriminatory phenotypic characteristics for identification. molecular methods such as amplified ribosomal dna restriction analysis (ardra) now enable the accurate identification of species. ten clinical isolates of acinetobacter radioresistens had genospecies confirmed by ardra but the apj 20ne system, commonly used in clinical microbiology laboratories, mis-identi ...19989699144
comparative studies of the acinetobacter genus and the species identification method based on the reca sequences.the reca gene is indispensable for a maintaining and diversification of the bacterial genetic material. given its important role in ensuring cell viability, it is not surprising that the reca protein is both ubiquitous and well conserved among a range of prokaryotes. previously, we reported acinetobacter genomic species identification method based on pcr amplification of an internal fragment of the reca gene with subsequent restriction analysis (rflp) with hinfi and mboi enzymes. in present stud ...200212005442
distribution of acinetobacter species on skin of healthy humans.the distribution of the 19 currently known genospecies of acinetobacter on human skin, i.e. forehead, forearm and toe webs, was determined. three selective media were compared for their specificity for all genospecies of acinetobacter. a minimal-salts agar supplemented with 1% acetate proved to be more efficient than the leeds medium for the isolation of most genospecies in mixed culture with other bacterial species. acinetobacter isolates were provisionally identified using biochemical tests an ...199910357050
cloning and complete nucleotide sequence of acinetobacter radioresistens cmc-1 aglya gene encoding serine hydroxymethyltransferase.a gene (aglya) encoding serine hydroxymethyltransferase of acinetobacter radioresistens cmc-1 was cloned and sequenced. nucleotide sequence analysis of aglya predicted a single open reading frame (orf) of 1251 bp encoding a 417-amino acid polypeptide. two putative metr-like binding sites (5'-tgaaacatgagct) and (5'-tgagcaaagttca), centered at bp -123 and -95 relative to the +1 translation start site were found, which have six out of nine and eight out of nine nucleotides that match to the consens ...19999933935
purification, biochemical properties and substrate specificity of a catechol 1,2-dioxygenase from a phenol degrading acinetobacter radioresistens.a catechol 1,2-dioxygenase (c1,2o) has been purified to homogeneity from acinetobacter radioresistens grown on phenol as the sole carbon and energy source. the c1,2o appears to be a homodimer, with a molecular mass of 78,000 da. at relatively high ionic strengths (0.5 m na2so4) subunit dissociation occurs and the monomeric unit (38,700 da) is shown to be active. this phenomenon has never been observed before in dioxygenases. the purified c1,2o contains 0.96 iron(iii) ions per unit and spectrosco ...19979369233
alasan, a new bioemulsifier from acinetobacter radioresistens.acinetobacter radioresistens ka53, isolated by enrichment culture, was found to produce an extracellular, nondialyzable emulsifying agent (referred to as alasan) when grown on ethanol medium in a batch-fed reactor. the crude emulsifier was concentrated from the cell-free culture fluid by ammonium sulfate precipitation to yield 2.2 g of emulsifier per liter. alasan stabilized a variety of oil-in-water emulsions, including n-alkanes with chain lengths of 10 or higher, alkyl aromatics, liquid paraf ...19957574633
how carbapenem-resistant acinetobacter spp. established in a newly constructed hospital.annually increasing rates of carbapenem-resistant acinetobacter spp. were observed in a taiwan hospital since its establishment in november 1998 to march 2005. increasing consumption of carbapenems was also noticed. carbapenem-resistant acinetobacter spp. from 33 patients carried a class 1 integron. twenty-eight isolates were acinetobacter baumannii harbouring both isaba1 and an oxa-51-like gene. twenty-four of the 28 a. baumannii isolates had isaba1 upstream of the oxa-51-like gene. four a. bau ...200818359613
acinetobacter radioresistens metabolizing aromatic compounds. 2. biochemical and microbiological characterization of the strain.the metabolic potentialities of an acinetobacter radioresistens strain, isolated from the soil adjacent to an activated sludge plant, were investigated. among 26 aromatic substrates tested, only phenol, benzoate and catechol were metabolized. since this strain possessed abundant plasmid dna, the antibiotic and heavy metal resistance was examined, and the bacterial cells proved to be sensitive to all metals (ni, tl, pb, cd, ag, co, zn) and antibiotics tested except for fosfomycin and chlorampheni ...19979237384
acinetobacter radioresistens metabolizing aromatic compounds. 1. optimization of the operative conditions for phenol degradation.a strain of acinetobacter radioresistens was able to utilize phenol as the only carbon and energy source, after an acclimatization period of 3 days in which increasing phenol concentrations from 50 to 200 mg/l were supplied. at 30 degrees c, the complete phenol utilization in batch degradation tests occurred in 2.5-3 h at ph 7 and 8, but it increased strongly at ph 6 (over 40 h). no microbial growth was detected at 40 degrees c, while at 20 degrees c (ph 7-8) the time necessary for complete phen ...19969178532
solubilization of polyaromatic hydrocarbons by recombinant bioemulsifier alna.alna is the protein responsible for the emulsifying and solubilizing activity of the acinetobacter radioresistens ka53 bioemulsifier alasan. alna was produced in escherichia coli, purified to homogeneity and then used to measure the enhanced solubility of 12 polyaromatic hydrocarbons (pahs). the amount of pah solubilized was directly proportional to alna concentration. the ratio of pah solubilized by 40 micro g/ml alna compared to that soluble in the aqueous buffer varied greatly, from 4 (fluore ...200212172629
structural roles of the active site iron(iii) ions in catechol 1,2-dioxygenases and differential secondary structure changes in isoenzymes a and b from acinetobacter radioresistens s13.the reversible active site metal ion removal process for two catechol 1,2-dioxygenase isoenzymes (isoa and isob) isolated from acinetobacter radioresistens s13 has been monitored using circular dichroism and fluorescence spectroscopic techniques. isoa and isob are homodimers, containing one iron(iii) ion per subunit. their amino acid sequence identity is 48.4%. previous experiments suggested that structural diversities could be responsible for the differential thermal and ph stabilities of the t ...200415464729
biomass relationship to growth and phosphate uptake of pseudomonas fluorescens, escherichia coli and acinetobacter radioresistens in mixed liquor medium.the ability of pseudomonas fluorescens, escherichia coli and acinetobacter radioresistens to remove phosphate during growth was related to the initial biomass as well as to growth stages and bacterial species. phosphate was removed by these bacteria under favourable conditions as well as under unfavourable conditions of growth. experiments showed a relationship between a high initial cell density and phosphate uptake. more phosphate was released than removed when low initial cell densities (10(2 ...19968987495
degradation of aromatic compounds by acinetobacter radioresistens s13: growth characteristics on single substrates and mixtures.acinetobacter radioresistens s13 is able to grow on phenol or benzoate as the sole carbon and energy source: both these compounds are catabolized through the beta-ketoadipate pathway. genes encoding the catabolic enzymes for degradation of aromatic compounds are localized on a. radioresistens s13 chromosome and organized in, at least, two distinct sets, one for benzoate degradation and another for phenol catabolism. in the present study, the growth and biodegradation kinetics for benzoate and ph ...200717483933
environmental significance of o-demethylation of chloroanisoles by soil bacterial isolates as a mechanism that improves the overall biodegradation of chlorophenols.the biodegradation rate of chlorophenols in the environment seems to be limited by a competitive mechanism of o-methylation which produces chloroanisoles with a high potential of being bioconcentrated in living organisms. in this work we report for the first time the isolation of three soil bacterial strains able to efficiently degrade 2,4,6-trichloroanisole (2,4,6-tca). these strains were identified as xanthomonas retroflexus inbb4, pseudomonas putida inbp1 and acinetobacter radioresistens inbs ...200717803776
phenol hydroxylase from acinetobacter radioresistens s13. isolation and characterization of the regulatory component.this paper reports the isolation and characterization of the regulatory moiety of the multicomponent enzyme phenol hydroxylase from acinetobacter radioresistens s13 grown on phenol as the only carbon and energy source. the whole enzyme comprises an oxygenase moiety (pho), a reductase moiety (phr) and a regulatory moiety (phi). phr contains one fad and one iron-sulfur cluster, whose function is electron transfer from nadh to the dinuclear iron centre of the oxygenase. phi is required for catalysi ...200312653998
the oxygenase component of phenol hydroxylase from acinetobacter radioresistens s13.phenol hydroxylase (ph) from acinetobacter radioresistens s13 represents an example of multicomponent aromatic ring monooxygenase made up of three moieties: a reductase (phr), an oxygenase (pho) and a regulative component (phi). the function of the oxygenase component (pho), here characterized for the first time, is to bind molecular oxygen and catalyse the mono-hydroxylation of substrates (phenol, and with less efficiency, chloro- and methyl-phenol and naphthol). pho was purified from extracts ...200312752444
ice-active characteristics of soil bacteria selected by ice-affinity.as an initial screen for microorganisms that produce ice-active macromolecules, ice-affinity was used to select microorganisms from soil consortia originating from three temperate regions. once selected and subsequently purified to single colonies, these microbes were putatively identified by 16s ribosomal rna sequencing and assayed for various ice-active properties. ice-affinity selection appeared to select for bacteria with ice-associating activities: inhibition of ice recrystallization; ice n ...200616958762
detailed characterization of the lipid a fraction from the nonpathogen acinetobacter radioresistens strain s13.the genus acinetobacter is composed of ubiquitous, generally nonpathogen environmental bacteria. interest concerning these microorganisms has increased during the last 30 years, because some strains, belonging to the so-called a. baumannii-a. calcoaceticus complex, have been implicated in some severe pathological states in debilitated and hospitalized patients. the involvement of lipopolysaccharides (lpss) as virulence factors in infections by acinetobacter has been proven, and ongoing studies a ...200717272830
codetection of blaoxa-23-like gene (blaoxa-133) and blaoxa-58 in acinetobacter radioresistens: report from the sentry antimicrobial surveillance program. 200919015330
persistence of biomarker atp and atp-generating capability in bacterial cells and spores contaminating spacecraft materials under earth conditions and in a simulated martian environment.most planetary protection research has concentrated on characterizing viable bioloads on spacecraft surfaces, developing techniques for bioload reduction prior to launch, and studying the effects of simulated martian environments on microbial survival. little research has examined the persistence of biogenic signature molecules on spacecraft materials under simulated martian surface conditions. this study examined how endogenous adenosine-5'-triphosphate (atp) would persist on aluminum coupons u ...200818567687
diversity of tetracycline resistance genes in bacteria from chilean salmon farms.twenty-five distinct tetracycline-resistant gram-negative bacteria recovered from four chilean fish farms with no history of recent antibiotic use were examined for the presence of tetracycline resistance (tet) genes. sixty percent of the isolates carried 1 of the 22 known tet genes examined. the distribution was as follows. the tet(a) gene was found in six isolates. the tet(b) gene was found in two isolates, including the first description in the genus brevundimonas: two isolates carried the te ...200312604516
improvements in lipase production and recovery from acinetobacter radioresistens in presence of polypropylene powders filled with carbon sources.polypropylene powders as the adsorbent for organic solution containing n-hexadecane and olive oil were employed as the carbon source for producing an alkaline lipase from acinetobacter radioresistens. the best volumetric ratio of n-hexadecane to olive oil around 5 for lipase production was determined from shake-flask and fermentation cultivations. the existence of a maximum time course lipase activity of the aqueous phase was attributed to the compensation effects of olive oil on cell growth and ...200312603101
surveillance of an adult intensive care unit for long-term persistence of a multi-resistant strain of acinetobacter baumannii.sporadic infections with acinetobacter spp., punctuated with prolonged outbreaks of infection involving larger numbers of patients and a particular epidemic strain of acinetobacter baumannii, have occurred in the adult intensive care unit (icu) of nottingham university hospital since 1985. the aim of this study was to screen patients admitted to the icu for three or more days during a non-outbreak period in 1994-1995 and to use dna fingerprinting techniques to compare any isolates of acinetobact ...19989665298
identification of the naturally occurring genes encoding carbapenem-hydrolysing oxacillinases from acinetobacter haemolyticus, acinetobacter johnsonii, and acinetobacter calcoaceticus.clin microbiol infect abstract: carbapenem resistance is increasingly being reported among acinetobacter species, and results mostly from the expression of acquired carbapenem-hydrolysing oxacillinases (chdls). several acinetobacter species intrinsically possess chromosomal chdl genes: acinetobacter baumannii (bla(oxa-51) ), acinetobacter radioresistens (bla(oxa-23) ), and acinetobacter lwoffii (bla(oxa-134) ). we aimed to identify the progenitors of novel chdl-encoding genes for identification ...201122128805
membrane proteome of acinetobacter radioresistens s13 during aromatic exposure.study of the bacterial membrane proteome, though in its early stages, is a field of growing interest in the search for information about nutrient transport and processing. we tested different strategies and chemical compounds to extract proteins from the membranes (inner and outer) of acinetobacter radioresistens s13, a gram-negative bacterium selected for its ability to degrade aromatics. a. radioresistens s13 was monitored under different growth substrate conditions, using acetate, benzoate or ...200312833532
Iron-based redox centres of reductase and oxygenase components of phenol hydroxylase from A. radioresistens: a redox chain working at highly positive redox potentials.This is the first report of the direct electrochemistry of the reductase (PHR) and oxygenase (PHO) components of phenol hydroxylase from Acinetobacter radioresistens S13 studied by cyclic and differential pulse voltammetry. The PHR contains one 2Fe2S cluster and one FAD that mediate the transfer of electrons from NAD(P)H to the non-heme diiron cluster of PHO. Cyclic and differential pulse voltammetry (CV and DPV) on glassy carbon showed two redox pairs with midpoint potentials at +131.5 ± 13 mV ...201121984271
microbial characterization of the mars odyssey spacecraft and its encapsulation facility.microbial characterization of the mars odyssey spacecraft and the kennedy space center spacecraft assembly and encapsulation facility ii (saef-ii) was carried out by both culture-based and molecular methods. the most dominant cultivable microbes were species of bacillus, with comamonads, microbacteria and actinomycetales also represented. several spore-forming isolates were resistant to gamma-radiation, uv, h2o2 and desiccation, and one acinetobacter radioresistens isolate and several aureobasid ...200314510851
antibodies to acinetobacter bacteria and bovine brain peptides, measured in bovine spongiform encephalopathy (bse) in an attempt to develop an ante-mortem test.bovine spongiform encephalopathy (bse) is a neurological disease of cattle. antibody responses to acinetobacter radioresistens and six other bacteria, as well as to bovine myelin basic protein and bovine neurofilaments were measured in 128 bse positive animals, 63 bse negative animals and 64 healthy control animals. animals positive for bse had the highest levels of antibodies to acinetobacter radioresistens (p < 0.0001) and also autoantibodies to bovine myelin basic protein (p < 0.0001) and bov ...200315079887
recovery of acinetobacter radioresistens lipase by hydrophobic adsorption to n-hexadecane coated on nonwoven fabric.a simple and clean adsorption/desorption process was proposed for recovering acinetobacter radioresistens lipase from fermentation broth. the adsorbent used was n-hexadecane coated on a hydrophobic nonwoven fabric (nwf). n-hexadecane has a melting point of 16-18 degrees c, and its affinity for lipase decreases markedly from liquid to solid state. accordingly, performing the adsorption and desorption above and below, respectively, the melting point would need no extraneous materials for separatio ...200312675588
the alnb protein of the bioemulsan alasan is a peroxiredoxin.the bioemulsifier of acinetobacter radioresistens ka53, referred to as alasan, is a high molecular weight complex of a polysaccharide and three proteins (alna, alnb and alnc). alna has previously been shown to be an ompa-like protein that is largely responsible for the emulsifying activity of alasan. to further elucidate the nature of alasan, the gene coding for alnb was cloned, sequenced and overexpressed in escherichia coli. the overall 561 bp sequence of the hypothetical alnb showed strong ho ...200415630518
proteomic analysis of the benzoate degradation pathway in acinetobacter sp. ks-1.the purpose of this study was to perform proteome analysis of acinetobacter sp. ks-1, a bacterium capable of degrading benzoate as a sole carbon source. in order to understand the benzoate degradation pathway used by strain ks-1, proteomes of benzoate-cultured and succinate-cultured ks-1 were comparatively analyzed by two dimensional gel electrophoresis (2-de). eighteen protein spots proteins were exclusively induced from the benzoate-cultured strain ks-1. of these 18 spots, two benzoate-degradi ...200314643408
structural elucidation of the core-lipid a backbone from the lipopolysaccharide of acinetobacter radioresistens s13, an organic solvent tolerant gram-negative bacterium.the structure of the core oligosaccharide of the lipopolysaccharide from an organic solvent tolerant gram-negative bacterium, acinetobacter radioresistens s13, was investigated by chemical analysis, nmr spectroscopy and maldi-tof mass spectrometry. all the experiments were performed on the oligosaccharides obtained either by alkaline degradation or mild acid hydrolysis. the data showed the presence of two novel oligosaccharide molecules containing a trisaccharide of 3-deoxy-d-manno-octulopyranos ...200616445894
the acinetobacter outer membrane protein a (ompa) is a secreted emulsifier.acinetobacter strains use hydrophobic carbon sources and most of them are efficient oil degraders. they secrete a variety of emulsifiers which are efficient in producing and stabilizing oil-in-water emulsions. the bioemulsifier of acinetobacter radioresistens ka53 (alasan) is a high-mass complex of proteins and polysaccharides. the major emulsification activity of this complex is associated with a 45 kda protein (alna), which is homologous to the outer membrane protein ompa. the emulsification a ...200616689723
catalytic properties of catechol 1,2-dioxygenase from acinetobacter radioresistens s13 immobilized on nanosponges.catechol 1,2-dioxygenases are iron containing enzymes able to convert catechol into cis,cis-muconate, a precursor of the industrially important compound adipic acid. catechol 1,2-dioxygenase from acinetobacter radioresistens s13 was immobilized on beta-cyclodextrins cross-linked with carbonate groups (nanosponges) with a yield of 29 mg of enzyme per gram of support. this support was chosen for its low cost and its ability to offer different types of interactions with the enzyme. the activity pro ...200919672496
effects of surface hydrophobicity on the catalytic iron ion retention in the active site of two catechol 1,2-dioxygenase isoenzymes.the different behaviour of two isozymes (isoa and isob) of catechol 1,2-dioxygenase (c 1,20) from acinetobacter radioresistens s13 on a hydrophobic interaction, phenyl-sepharose chromatographic column, prompted us to investigate the role of superficial hydrophobicity on structural-functional aspects for such class of enzymes. the interaction of 8-anilino-1-naphtalenesulphonate (ans), a fluorescent probe known to bind to hydrophobic sites in proteins, revealed that the two isoenzymes have a marke ...200415689112
clinically significant carbapenemases: an update.to provide a brief synopsis of studies which have extended our understanding of carbapenem resistance in clinical isolates in terms of epidemiology, mechanism of action and genetic factors affecting their carriage and spread.200818594288
x-ray crystallography, mass spectrometry and single crystal microspectrophotometry: a multidisciplinary characterization of catechol 1,2 dioxygenase.intradiol-cleaving catechol 1,2 dioxygenases are fe(iii) dependent enzymes that act on catechol and substituted catechols, including chlorocatechols pollutants, by inserting molecular oxygen in the aromatic ring. members of this class are the object of intense biochemical investigations aimed at the understanding of their catalytic mechanism, particularly for designing mutants with selected catalytic properties. we report here an in depth investigation of catechol 1,2 dioxygenase isob from acine ...201020869471
biodegradation of methyl parathion by acinetobacter radioresistens ustb-04.biodegradation of methyl parathion (mp), a widely used organophosphorus pesticide, was investigated using a newly isolated bacterium strain acinetobacter radioresistens ustb-04. mp at an initial concentration of 1200 mg/l could be totally biodegraded by a. radioresistens ustb-04 as the sole carbon source less than 4 d in the presence of phosphate and urea as phosphorus and nitrogen sources, respectively. biodegradation of mp was also achieved using cell-free extract of a. radioresistens ustb-04. ...200718062427
combined cup loading, bis(2-hydroxyethyl) disulfide, and protein precipitation protocols to improve the alkaline proteome of lactobacillus hilgardii.despite the large number of papers dealing with bacterial proteomes, very few include information about proteins with alkaline pi's, because of the limits inherent in 2-de technology. nonetheless, analyses of in silico proteomes of many prokaryotes show a bimodal distribution of their proteins based on their pi's; the most crowded areas lying between pi 4-7 and 9-11. the aim of the present research was to set up a general, simple, and standardizable 2-de protocol suitable for studying the alkali ...200717492720
analysis of bacterial community during the fermentation of pulque, a traditional mexican alcoholic beverage, using a polyphasic approach.in this study, the characterization of the bacterial community present during the fermentation of pulque, a traditional mexican alcoholic beverage from maguey (agave), was determined for the first time by a polyphasic approach in which both culture and non-culture dependent methods were utilized. the work included the isolation of lactic acid bacteria (lab), aerobic mesophiles, and 16s rdna clone libraries from total dna extracted from the maguey sap (aguamiel) used as substrate, after inoculati ...200818450312
identification of a novel baeyer-villiger monooxygenase from acinetobacter radioresistens: close relationship to the mycobacterium tuberculosis prodrug activator etaa.this work demonstrates that acinetobacter radioresistens strain s13 during the growth on medium supplemented with long-chain alkanes as the sole energy source expresses alma gene coding for a baeyer-villiger monooxygenase (bvmo) involved in alkanes subterminal oxidation. phylogenetic analysis placed the sequence of this novel bvmo in the same clade of the prodrug activator ethionamide monooxygenase (etaa) and it bears only a distant relation to the other known class i bvmo proteins. in silico an ...201222862894
escherichia coli overexpressing a baeyer-villiger monooxygenase from acinetobacter radioresistens becomes resistant to imipenem.antimicrobial resistance is a global issue currently resulting in the deaths of hundreds of thousands of people a year worldwide. data present in the literature illustrate the emergence of many bacterial species that display resistance to known antibiotics; acinetobacter spp. are a good example of this. we report here that acinetobacter radioresistens has a baeyer-villiger monooxygenase (ar-bvmo) with 100% amino acid sequence identity to the ethionamide monooxygenase of multidrug-resistant (mdr) ...201526459905
acinetobacter indicus sp. nov., isolated from hexachlorocyclohexane (hch) dumpsite.taxonomic position of a gram-negative, non-motile, oxidase negative and catalase positive strain a648t, isolated from hexachlorocyclohexane (hch) dumpsite located in lucknow, india was ascertained using a polyphasic approach. a comparative analysis of partial sequence of the rpob gene and 16s rrna gene sequence revealed that strain a648t belongs to the genus acinetobacter. dna-dna relatedness values between strain a648t and other closely related members namely acinetobacter radioresistens dsm 69 ...201222247213
radiation sensitivity of acinetobacter spp. and their redicidation for preservation of meat at low temperature.in recent years, interest has been growing to preserve food including meat applying gamma radiation recommended by international atomic energy agency to extend the shelf-life of meat retaining the organoleptic conditions as it is. in view of this point the present study aims to check the sensitivity of acinetobacter spp. isolated from meat to gamma radiations. seven species of acinetobacter viz. a. lwoffli m1; a. baumannii m8; a. calcoaceticus m19; a. junii m20; a. johnsonnii m23; a. haemolyticu ...200920120776
high isoelectric point sub-proteome analysis of acinetobacter radioresistens s13 reveals envelope stress responses induced by aromatic compounds.in the present study, the high isoelectric point sub-proteome of acinetobacter radioresistens s13 grown on aromatic compounds (benzoate or phenol) was analyzed and compared to the protein pattern, in the same pi range, of acetate-grown bacteria (control condition). analyses concerned both soluble and membrane enriched proteomes and led to the identification of 25 proteins that were differentially expressed among the growth conditions considered: most of them were up-regulated in cells grown on a ...201020953507
isolation of acinetobacter radioresistens from a clinical sample in bulgaria.we report on the role of acinetobacter radioresistens in a case of pneumonia in an elderly patient and describe the challenge of correct identification of this species. a tracheobronchial culture taken from a patient in a bulgarian hospital yielded a pure culture of gram-negative, lactose-non-fermenting bacilli on macconkey agar. genus and species identification was performed by biochemical tests and sequencing of the rpob gene. antimicrobial susceptibility testing and screening for blaoxa-like ...201627436395
characterization of a new catechol branch of the beta-ketoadipate pathway induced for benzoate degradation in acinetobacter lwoffii k24.acinetobacter lwoffii k24 is a known aniline-degrading bacterium. in previous studies, two catechol branches of the beta-ketoadipate pathway were reported to be induced for aniline degradation, and related enzymes (cata(1) and cata(2)) were identified from the aniline-induced proteome of a. lwoffii k24 [s.i. kim, s.h. leem, j.s. choi, y.h. chung, s. kim, y.m. park, y.k. park, y.n. lee, k.s. ha, cloning and characterization of two cata genes in acinetobacter lwoffii k24, j. bacteriol. 179 (1997) ...200717610839
acinetobacter radioresistens as a silent source of carbapenem resistance for acinetobacter spp.carbapenem resistance results mostly from the expression of acquired carbapenem-hydrolyzing oxacillinases in acinetobacter baumannii. the bla oxa-23 oxacillinase gene is increasingly reported worldwide and may represent an emerging threat. our goal was to identify the progenitor of that carbapenemase gene. a collection of 50 acinetobacter sp. strains corresponding to several acinetobacter species was screened for bla(oxa-23)-like genes by pcr and hybridization techniques. five acinetobacter radi ...200818195058
characterization of a serine hydroxymethyltransferase for l-serine enzymatic production from pseudomonas plecoglossicida.pseudomonas plecoglossicida, a bacterium strain that exhibits high serine hydroxymethyltransferase (shmt) activity, was isolated from the seawater. a full-length glya encoding shmt was obtained by a modified thermal asymmetric interlaced-pcr (tril-pcr), which consisted of 1,254 bp, encoded a 417 amino acid polypeptide, and shared the highest identity (75 %) with a glya gene from acinetobacter radioresistens cmc-1. recombinant glya gene was expressed in escherichia coli bl21 (de3) and purified by ...201323913024
draft genome sequence of the plant growth-promoting rhizobacterium acinetobacter radioresistens strain sa188 isolated from the desert plant indigofera argentea.acinetobacter radioresistens strain sa188 is a plant endophytic bacterium, isolated from root nodules of the desert plants indigofera spp., collected in jizan, saudi arabia. here, we report the 3.2-mb draft genome sequence of strain sa188, highlighting characteristic pathways for plant growth-promoting activity and environmental adaptation.201728254978
rapid detection of blaoxa in carbapenem-susceptible acinetobacter radioresistens bacteremia leading to unnecessary antimicrobial administration.rapid molecular techniques to identify resistant pathogens are revolutionizing antibiotic stewardship; however, it is important to recognize the limitations of these techniques. herein we describe two cases of bacteremia that were both initially identified by genotypic testing as carbapenem-resistant acinetobacter spp. and subsequently identified phenotypically as carbapenem-susceptible a. radioresistens. the genotypic results prompted unnecessary broad-spectrum antibiotic use and infection cont ...201627236714
draft genome sequences of acinetobacter parvus cm11, acinetobacter radioresistens cm38, and stenotrophomonas maltophilia br12, isolated from murine proximal colonic tissue.here, we report three genome sequences of bacteria isolated from murine proximal colonic tissue and identified as acinetobacter parvus cm11, acinetobacter radioresistens cm38, and stenotrophomonas maltophilia br12.201526472823
biodegradation of diesel oil by a novel microbial consortium: comparison between co-inoculation with biosurfactant-producing strain and exogenously added biosurfactants.bioremediation, involving the use of microorganisms to detoxify or remove pollutants, is the most interesting strategy for hydrocarbon remediation. in this aim, four hydrocarbon-degrading bacteria were isolated from oil-contaminated soil in tunisia. they were identified by the 16s rdna sequence analysis, as lysinibacillus bronitolerans ri18 (kf964487), bacillus thuringiensis ri16 (km111604), bacillus weihenstephanensis ri12 (km094930), and acinetobacter radioresistens ri7 (kj829530). moreover, a ...201525994261
molecular characterization of outer membrane vesicles released from acinetobacter radioresistens and their potential roles in pathogenesis.acinetobacter radioresistens is an important member of genus acinetobacter from a clinical point of view. in the present study, we report that a clinical isolate of a. radioresistens releases outer membrane vesicles (omvs) under in vitro growth conditions. omvs were released in distinctive size ranges with diameters from 10 to 150 nm as measured by the dynamic light scattering (dls) technique. additionally, proteins associated with or present into omvs were identified using lc-esi-ms/ms. a total ...201525940676
an unusual infection outbreak in rats held in a human hospital research laboratory.most animal hazards in laboratories are widely recognized. these, together with zoonoses and other possible insults, are subject to the establishment of guidelines for the operation and maintenance of such facilities. most of the infectious diseases described among laboratory animals are related to the inadequate implementation of preventive and quality control policies. these included surgical, respiratory and intestinal tract infections, and typically spread between animals. this report is abo ...201525732573
cyp116b5: a new class vii catalytically self-sufficient cytochrome p450 from acinetobacter radioresistens that enables growth on alkanes.a gene coding for a class vii cytochrome p450 monooxygenase (cyp116b5) was identified from acinetobacter radioresistens s13 growing on media with medium (c14, c16) and long (c24, c36) chain alkanes as the sole energy source. phylogenetic analysis of its n- and c-terminal domains suggests an evolutionary model involving a plasmid-mediated horizontal gene transfer from the donor rhodococcus jostii rha1 to the receiving a. radioresistens s13. this event was followed by fusion and integration of the ...201525425282
a pseudo-outbreak due to acinetobacter species (gim-1) contamination of the pneumatic transport system of a large university hospital.to establish the source and contamination routes resulting in positive clinical and surveillance microbiological cultures with carbapenem-resistant, gim-1 metallo-β-lactamase-positive acinetobacter pitii and acinetobacter radioresistens from 21 patients in 8 departments.201425333431
ormosil gels doped with engineered catechol 1,2 dioxygenases for chlorocatechol bioremediation.enzymes entrapped in wet, nanoporous silica gel have great potential as bioreactors for bioremediation because of their improved thermal, chemical, and mechanical stability with respect to enzymes in solution. the b isozyme of catechol 1,2 dioxygenase from acinetobacter radioresistens and its mutants of leu69 and ala72, designed for an increased reactivity toward the environmental pollutant chlorocatechols, were encapsulated using alkoxysilanes and alkyl alkoxysilanes as precursors in varying pr ...201424571591
an epr, thermostability and ph-dependence study of wild-type and mutant forms of catechol 1,2-dioxygenase from acinetobacter radioresistens s13.intradiol dioxygenase are iron-containing enzymes involved in the bacterial degradation of natural and xenobiotic aromatic compounds. the wild-type and mutants forms of catechol 1,2-dioxygenase iso b from acinetobacter radioresistens lmg s13 have been investigated in order to get an insight on the structure-function relationships within this system. 4k cw-epr spectroscopy highlighted different oxygen binding properties of some mutants with respect to the wild-type enzyme, suggesting that a fine ...201323224984
identification of a novel insertion sequence element associated with carbapenem resistance and the development of fluoroquinolone resistance in acinetobacter radioresistens. 201323139290
insights into the extremotolerance of acinetobacter radioresistens 50v1, a gram-negative bacterium isolated from the mars odyssey spacecraft.the microbiology of the spacecraft assembly process is of paramount importance to planetary exploration, as the biological contamination that can result from remote-enabled spacecraft carries the potential to impact both life-detection experiments and extraterrestrial evolution. accordingly, insights into the mechanisms and range of extremotolerance of acinetobacter radioresistens 50v1, a gram-negative bacterium isolated from the surface of the preflight mars odyssey orbiter, were gained by usin ...201222917036
biodegradation of trichloroethylene and toluene by indigenous microbial populations in vadose sediments.the unsaturated subsurface (vadose zone) receives significant amounts of hazardous chemicals, yet little is known about its microbial communities and their capacity to biodegrade pollutants. trichloroethylene (tce) biodegradation occurs readily in surface soils; however, the process usually requires enzyme induction by aromatic compounds, methane, or other cosubstrates. the aerobic biodegradation of toluene and tce by indigenous microbial populations was measured in samples collected from the va ...199524185349
bacterial pathogens and health problems of acipenser gueldenstaedtii and acipenser baerii sturgeons reared in the eastern black sea region of turkey.farming sturgeons is an economically important practice in a number of asian and european countries. however, since it is not widely implementedin turkey, fertilized eggs necessary for research and industrial activities are imported from germany. due to the interest of several fish farms in culturing sturgeon in turkey and the lack of relevant data, this study investigated bacteria related health problems of two different sturgeon species, the diamond sturgeon (acipenser gueldenstaedtii) and the ...201728580011
analysis of imp-1 type metallo-β-lactamase-producing acinetobacter radioresistens isolated from companion animals.imp-1 type metallo-β-lactamase-producing (mbl-producing) acinetobacter radioresistens was isolated from a dog with cystitis and a cat with conjunctivitis. the mbl-producing a. radioresistens isolates were resistant to all of the β-lactam antibiotics used in the sensitivity tests, but were susceptible to gentamicin, amikacin, and minocycline. also, one of the two strains of a. radioresistens was susceptible to ciprofloxacin and levofloxacin. these two cases were cured by administration of tetracy ...201728408304
scale-up and inhibitory studies on productivity of lipase from acinetobacter radioresistens pr8.acinetobacter radioresistens pr8 produces extracellular lipase depending upon growth media. in present work we not only screened the nutrient sources but also investigated the causes for variation in productivity. the nutrient sources investigated are, groundnut oil, groundnut cake and fresh groundnut. lower lipase productivity was observed on fresh ground nut in contrast to groundnut oil and groundnut cake. the lipase productivity was examined in the batch and parameters monitored were bacteria ...201728408095
a five-gene cluster involved in utilization of taurine-nitrogen and excretion of sulfoacetaldehyde by acinetobacter radioresistens sh164.acinetobacter calcoaceticus sw1, under nitrogen limitation, assimilates the nitrogen moiety of taurine (2-aminoethanesulfonate) inducibly and excretes sulfoacetaldehyde, a product of taurine dehydrogenase (tauxy). blast searches of newly available genome sequences using the tauxy sequences revealed a 5-gene cluster, taurxypi, in acinetobacter radioresistens sh164. we hypothesized that tauxypi (hmpref0018_00717-hmpref0018_00720) encodes proteins that are orthologs of the undefined pathway from st ...201222588221
identification of a novel phospholipase d with high transphosphatidylation activity and its application in synthesis of phosphatidylserine and dha-phosphatidylserine.phosphatidylserine (ps) and docosahexaenoic acid-phosphatidylserine (dha-ps) have significant nutritional and biological functions, which are extensively used in functional food industries. phospholipase d (pld)-mediated transphosphatidylation of phosphatidylcholine (pc) or dha-pc with l-serine, is an effective method for ps and dha-ps preparation. however, because of the hydrolysis activity of pld, pc and dha-pc would be converted to the undesirable byproduct, phosphatidic acid (pa) and dha-pa. ...201728347768
characterization of a new baeyer-villiger monooxygenase and conversion to a solely n-or s-oxidizing enzyme by a single r292 mutation.ar-bvmo is a recently discovered baeyer-villiger monooxygenase from the genome of acinetobacter radioresistens s13 closely related to medically relevant ethionamide monooxygenase etaa (prodrug activator) and capable of inactivating the imipenem antibiotic.201627344049
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