| synthesis and biological activities of diflunisal hydrazide-hydrazones. | several diflunisal hydrazide-hydrazone derivatives namely 2',4'-difluoro-4-hydroxybiphenyl-3-carboxylic acid [(5-nitro-2-furyl/substitutedphenyl)methylene] hydrazide (3a-o) have been synthesised. methyl 2',4'-difluoro-4-hydroxybiphenyl-3-carboxylate (1) and 2',4'-difluoro-4-hydroxybiphenyl-3-carboxylic acid hydrazide (2) were also synthesised and used as intermediate compounds. all synthesised compounds were screened for their antimycobacterial activity against mycobacterium tuberculosis h37 rv, ... | 2003 | 14642333 |
| exposure to bioaerosols in a municipal sewage treatment plant. | microbiological air sampling was performed in a medium-size sewage treatment plant processing municipal wastewater from a city located in eastern poland. air samples for determination of the concentrations of viable mesophilic bacteria, gram-negative bacteria, thermophilic actinomycetes, fungi and endotoxin were collected at 12 sites associated with various phases of sewage treatment process. the concentrations of total mesophilic bacteria (both gram-positive and gram-negative) were within a ran ... | 2003 | 14677919 |
| occurrence and characterization of mercury resistance in the hyperthermophilic archaeon sulfolobus solfataricus by use of gene disruption. | mercury resistance mediated by mercuric reductase (mera) is widespread among bacteria and operates under the control of merr. merr represents a unique class of transcription factors that exert both positive and negative regulation on gene expression. archaea and bacteria are prokaryotes, yet little is known about the biological role of mercury in archaea or whether a resistance mechanism occurs in these organisms. the archaeon sulfolobus solfataricus was sensitive to mercuric chloride, and low-l ... | 2004 | 14702312 |
| comparison in a rat thigh abscess model of imipenem, meropenem and cefoperazone-sulbactam against acinetobacter baumannii strains in terms of bactericidal efficacy and resistance selection. | we compared imipenem, meropenem and cefoperazone-sulbactam against hospital originated a. baumannii strains in terms of bactericidal efficacy and selection of resistant mutants during treatment in a rat thigh abscess model. | 2004 | 14713318 |
| pqq glucose dehydrogenase with novel electron transfer ability. | pqq glucose dehydrogenase from acinetobacter calcoaceticus (gdh-b) is one of the most industrially attractive enzymes, as a sensor constituent for glucose sensing, because of its high catalytic activity and insensitivity to oxygen. we attempted to engineer gdh-b to enable electron transfer to the electrode in the absence of artificial electron mediator by mimicking the domain structure of the quinohemoprotein ethanol dehydrogenase (qh-edh) from comamonas testosteroni, which is composed of a pqq- ... | 2004 | 14741705 |
| genetic environment and transcription of ampc in an acinetobacter baumannii clinical isolate. | an ampc gene was cloned from a clinical isolate of acinetobacter baumannii (strain ran). dna sequencing and primer extension studies showed that ampc is transcribed from a promoter contained within a putative insertion sequence element which has been found to abut several different genes in acinetobacter spp. | 2004 | 14742218 |
| endophthalmitis caused by acinetobacter calcoaceticus. a profile. | to report the clinical and microbiological profile of endophthalmitis caused by acinetobacter calcoaceticus. | 2003 | 14750622 |
| improved laboratory enrichment for enterohemorrhagic escherichia coli by exposure to extremely acidic conditions. | analysis of food samples for e. coli o157:h7 using the standard u.s. food and drug administration procedure is frequently complicated by overgrowth of nontarget microorganisms. a new procedure was developed for enrichment of enterohemorrhagic e. coli (ehec) which utilizes exposure to ph 2.00 for 2 h. this procedure yielded larger populations of ehec than the standard method by factors ranging from 2.7 to 7.7 and, when age-stressed cultures were used, by factors ranging from 2.7 to 11.5. cultures ... | 2004 | 14766610 |
| biased distribution of dna uptake sequences towards genome maintenance genes. | repeated sequence signatures are characteristic features of all genomic dna. we have made a rigorous search for repeat genomic sequences in the human pathogens neisseria meningitidis, neisseria gonorrhoeae and haemophilus influenzae and found that by far the most frequent 9-10mers residing within coding regions are the dna uptake sequences (dus) required for natural genetic transformation. more importantly, we found a significantly higher density of dus within genes involved in dna repair, recom ... | 2004 | 14960717 |
| oral bacterial flora of dogs with and without rabies: a preliminary study in thailand. | the authors studied the bacterial flora of the dog oral cavity and of bite wounds, aerobic bacteria were isolated from mouth swabs of 16 normal and 5 rabid dogs as well as from infected dog-bite wounds from 18 patients. a total of 20 different microbial species were recovered from mouth swab cultures. the most frequently isolated organisms were klebsiella pneumoniae ssp pneumoniae, escherichia coli, staphylococcus aureus, citrobacter freundii, enterobacter cloacae, acinetobacter calcoaceticus, a ... | 2003 | 14971525 |
| rapid quantification of yersinia enterocolitica in pork samples by a novel sample preparation method, flotation, prior to real-time pcr. | the development of real-time pcr thermal cycles in the late 1990s has opened up the possibility of accurate quantification of microorganisms in clinical, environmental, and food samples. however, a lack of suitable sample preparation methods that allow rapid quantification of the nucleic acids, remove pcr inhibitors, and prevent false-positive results due to dna originating from dead cells has limited the use of quantitative pcr. we have used for the first time a new variant of density gradient ... | 2004 | 15004051 |
| characteristics of a new enantioselective thermostable dipeptidase from brevibacillus borstelensis bcs-1 and its application to synthesis of a d-amino-acid-containing dipeptide. | a new thermostable dipeptidase gene was cloned from the thermophile brevibacillus borstelensis bcs-1 by genetic complementation of the d-glu auxotroph escherichia coli wm335 on a plate containing d-ala-d-glu. nucleotide sequence analysis revealed that the gene included an open reading frame coding for a 307-amino-acid sequence with an m(r) of 35,000. the deduced amino acid sequence of the dipeptidase exhibited 52% similarity with the dipeptidase from listeria monocytogenes. the enzyme was purifi ... | 2004 | 15006780 |
| a dna adenine methyltransferase of escherichia coli that is cell cycle regulated and essential for viability. | dna sequence analysis revealed that the putative yhdj dna methyltransferase gene of escherichia coli is 55% identical to the nostoc sp. strain pcc7120 gene encoding dna methyltransferase avaiii, which methylates adenine in the recognition sequence, atgcat. the yhdj gene was cloned, and the enzyme was overexpressed and purified. methylation and restriction analysis showed that the dna methyltransferase methylates the first adenine in the sequence atgcat. this dna methylation was found to be regul ... | 2004 | 15028690 |
| growth and lipase production of a psychrotrophic acinetobacter calcoaceticus in an msg-containing medium. | | 2004 | 15057708 |
| functional properties of borrelia burgdorferi reca. | functions of the borrelia burgdorferi reca protein were investigated in escherichia coli reca null mutants. complementation with b. burgdorferi reca increased survival of e. coli reca mutants by 3 orders of magnitude at a uv dose of 2,000 microj/cm(2). the viability at this uv dose was about 10% that provided by the homologous reca gene. expression of b. burgdorferi reca resulted in survival of e. coli at levels of mitomycin c that were lethal to noncomplemented hosts. b. burgdorferi reca was as ... | 2004 | 15060028 |
| crystal structure of 4-chlorocatechol 1,2-dioxygenase from the chlorophenol-utilizing gram-positive rhodococcus opacus 1cp. | the crystal structure of the 4-chlorocatechol 1,2-dioxygenase from the gram-positive bacterium rhodococcus opacus (erythropolis) 1cp, a fe(iii) ion-containing enzyme involved in the aerobic biodegradation of chloroaromatic compounds, has been solved by multiple wavelength anomalous dispersion using the weak anomalous signal of the two catalytic irons (1 fe/257 amino acids) and refined at a 2.5 a resolution (r(free) 28.7%; r factor 21.4%). the analysis of the structure and its comparison with the ... | 2004 | 15060064 |
| occurrence and phylogenetic diversity of sphingomonas strains in soils contaminated with polycyclic aromatic hydrocarbons. | bacterial strains of the genus sphingomonas are often isolated from contaminated soils for their ability to use polycyclic aromatic hydrocarbons (pah) as the sole source of carbon and energy. the direct detection of sphingomonas strains in contaminated soils, either indigenous or inoculated, is, as such, of interest for bioremediation purposes. in this study, a culture-independent pcr-based detection method using specific primers targeting the sphingomonas 16s rrna gene combined with denaturing ... | 2004 | 15066784 |
| evolutionary stability of dna uptake signal sequences in the pasteurellaceae. | the dna-uptake signal sequence (uss) of the bacterium haemophilus influenzae is highly over-represented in its genome (1,471 copies of the core sequence aagtgcggt), and dna fragments containing uss are preferentially taken up by competent cells. because this bias favors uptake of conspecific dna, usss are often considered a kind of mate recognition system in bacteria, acting as species-specific barriers against uptake of unrelated dna. however, the h. influenzae uss is highly over-represented in ... | 2004 | 15070749 |
| dissemination of a clone of unusual phenotype of pandrug-resistant acinetobacter baumannii at a university hospital in taiwan. | from december 2002 to february 2003, 15 isolates of pandrug-resistant unidentified acinetobacter species were recovered from seven patients treated on different wards or intensive care units. both 16s-23s rrna intergenic spacer pcr-restriction fragment length polymorphism profiles and sequence analysis of these isolates identified them as acinetobacter baumannii. this pandrug-resistant a. baumannii strain with an unusual phenotype could persist in humans for long periods and was widely dissemina ... | 2004 | 15071042 |
| a modular minimal cell model: purine and pyrimidine transport and metabolism. | a more complete understanding of the relationship of cell physiology to genomic structure is desirable. because of the intrinsic complexity of biological organisms, only the simplest cells will allow complete definition of all components and their interactions. the theoretical and experimental construction of a minimal cell has been suggested as a tool to develop such an understanding. our ultimate goal is to convert a "coarse-grain" lumped parameter computer model of escherichia coli into a gen ... | 2004 | 15090651 |
| partial analysis of the genomes of two nontypeable haemophilus influenzae otitis media isolates. | in 1995, the institute for genomic research completed the genomic sequence of a rough derivative of haemophilus influenzae serotype d, strain kw20. this sequence, though extremely useful in understanding the basic biology of h. influenzae, has yet to provide significant insight into our understanding of disease caused by nontypeable h. influenzae (nthi), because serotype d strains are not generally pathogens. in contrast, nthi strains are frequently mucosal pathogens and are the primary pathogen ... | 2004 | 15102813 |
| susceptibility of the acinetobacter calcoaceticus-a. baumannii complex to imipenem, meropenem, sulbactam and colistin. | the acinetobacter calcoaceticus-acinetobacter baumannii complex includes some of the most clinically relevant species of the genus acinetobacter due to their capacity to cause epidemic nosocomial outbreaks as well as their increasing resistance to antibiotics. susceptibility of acinetobacter strains varies greatly depending on origin, thus highlighting the importance of local analyses of susceptibility profiles. two hundred twenty-one strains of the a. calcoaceticus-a. baumannii complex were ide ... | 2004 | 15120728 |
| antibodies to prion and acinetobacter peptide sequences in bovine spongiform encephalopathy. | an amino acid sequence homology has been identified between the bovine prion sequence (rpvdq) and the acinetobacter calcoaceticus enzyme, uridine-diphosphate-n-acetyl glucosamine-1-carboxy-vinyl-transferase which also contains (rpvdq). class-specific iga, igg and igm antibodies against synthetic peptides containing the structurally related sequences present in bovine prion and a. calcoaceticus were measured in 189 bovine spongiform encephalopathy (bse) positive cattle, 127 bse negative cattle an ... | 2004 | 15127836 |
| spread of novel aminoglycoside resistance gene aac(6')-iad among acinetobacter clinical isolates in japan. | a novel aminoglycoside resistance gene, aac(6')-iad, encoding aminoglycoside 6'-n-acetyltransferase, was identified in acinetobacter genospecies 3 strain a-51. the gene encoded a 144-amino-acid protein, which shared modest identity (up to 36.7%) with some of the aminoglycoside 6'-n-acetyltransferases. the results of high-pressure liquid chromatography assays confirmed that the protein is a functional aminoglycoside 6'-n-acetyltransferase. the enzyme conferred resistance to amikacin, tobramycin, ... | 2004 | 15155202 |
| microbial hydroxylation of indole to 7-hydroxyindole by acinetobacter calcoaceticus strain 4-1-5. | a screening study yielded acinetobacter calcoaceticus strain 4-1-5, which is capable of hydroxylating indole to 7-hydroxyindole. strain 4-1-5 grew on terephthalate as the sole source of carbon and energy and hydroxylated indole to 7-hydroxyindole by cometabolism of indole using terephthalate as cosubstrate. strain 4-1-5 produced 0.574 mm of 7-hydroxyindole at 2.38 mm indole in 24 h with the cell growth. | 2004 | 15170130 |
| regulation of hypercompetence in legionella pneumophila. | although many bacteria are known to be naturally competent for dna uptake, this ability varies dramatically between species and even within a single species, some isolates display high levels of competence while others seem to be completely nontransformable. surprisingly, many nontransformable bacterial strains appear to encode components necessary for dna uptake. we believe that many such strains are actually competent but that this ability has been overlooked because standard laboratory condit ... | 2004 | 15175295 |
| typing and characterization of carbapenem-resistant acinetobacter calcoaceticus-baumannii complex in a chinese hospital. | this study was designed to investigate the prevalence of carbapenem-resistant acinetobacter calcoaceticus-baumannii complex (acb complex) and to type carbapenemases. the relatedness of 45 isolates of carbapenem-resistant acb complex collected from a clinical setting was analysed by pfge. the carbapenemases produced by these isolates were typed by ief, a three-dimensional test, 2-mercaptopropanoic acid inhibition assay, pcr and dna cloning and sequencing. results showed that all 45 isolates were ... | 2004 | 15184537 |
| mammalian wax biosynthesis. ii. expression cloning of wax synthase cdnas encoding a member of the acyltransferase enzyme family. | wax monoesters are synthesized by the esterification of fatty alcohols and fatty acids. a mammalian enzyme that catalyzes this reaction has not been isolated. we used expression cloning to identify cdnas encoding a wax synthase in the mouse preputial gland. the wax synthase gene is located on the x chromosome and encodes a member of the acyltransferase family of enzymes that synthesize neutral lipids. expression of wax synthase in cultured cells led to the formation of wax monoesters from straig ... | 2004 | 15220349 |
| induction of a novel class of diacylglycerol acyltransferases and triacylglycerol accumulation in mycobacterium tuberculosis as it goes into a dormancy-like state in culture. | mycobacterium tuberculosis enters the host by inhalation of an infectious aerosol and replicates in the alveolar macrophages until the host's immune defense causes bacteriostasis, which leads the pathogen to go into nonreplicative drug-resistant dormancy. the dormant pathogen can survive for decades till the host's immune system is weakened and active tuberculosis develops. even though fatty acids are thought to be the major energy source required for the persistence phase, the source of fatty a ... | 2004 | 15262939 |
| partial purification and characterization of a non-cyanobacterial cyanophycin synthetase from acinetobacter calcoaceticus strain adp1 with regard to substrate specificity, substrate affinity and binding to cyanophycin. | this study reports, for the first time, purification and biochemical characterization of a cyanophycin synthetase from a non-cyanobacterial strain. cyanophycin synthetase of acinetobacter calcoaceticus strain adp1 was purified 69-fold from recombinant escherichia coli by two chromatographic steps and one novel affinity step utilizing the mg(2+)-dependent binding of the enzyme to cyanophycin. unlike cyanobacterial cyanophycin synthetases characterized so far, the purified enzyme from a. calcoacet ... | 2004 | 15289556 |
| biochemical characterization of styab from pseudomonas sp. strain vlb120 as a two-component flavin-diffusible monooxygenase. | pseudomonas sp. vlb120 uses styrene as a sole source of carbon and energy. the first step in this metabolic pathway is catalyzed by an oxygenase (stya) and a nadh-flavin oxidoreductase (styb). both components have been isolated from wild-type pseudomonas strain vlb120 as well as from recombinant escherichia coli. stya from both sources is a dimer, with a subunit size of 47 kda, and catalyzes the enantioselective epoxidation of cc double bonds. styrene is exclusively converted to s-styrene oxide ... | 2004 | 15292130 |
| crystal structure of a baeyer-villiger monooxygenase. | flavin-containing baeyer-villiger monooxygenases employ nadph and molecular oxygen to catalyze the insertion of an oxygen atom into a carbon-carbon bond of a carbonylic substrate. these enzymes can potentially be exploited in a variety of biocatalytic applications given the wide use of baeyer-villiger reactions in synthetic organic chemistry. the catalytic activity of these enzymes involves the formation of two crucial intermediates: a flavin peroxide generated by the reaction of the reduced fla ... | 2004 | 15328411 |
| carb-9, a carbenicillinase encoded in the vcr region of vibrio cholerae non-o1, non-o139 belongs to a family of cassette-encoded beta-lactamases. | the gene bla(carb-9) was located in the vibrio cholerae super-integron, but in a different location relative to bla(carb-7). carb-9 (pi 5.2) conferred beta-lactam mics four to eight times lower than those conferred by carb-7, differing at ambler's positions v97i, l124f, and t228k. comparison of the genetic environments of all reported bla(carb) genes indicated that the carb enzymes constitute a family of cassette-encoded beta-lactamases. | 2004 | 15388476 |
| methylation of 23s rrna nucleotide g745 is a secondary function of the rlmai methyltransferase. | several groups of gram-negative bacteria possess an rlma(i) methyltransferase that methylates 23s rrna nucleotide g745 at the n1 position. inactivation of rlma(i) in acinetobacter calcoaceticus and escherichia coli reduces growth rates by at least 30%, supposedly due to ribosome malfunction. wild-type phenotypes are restored by introduction of plasmid-encoded rlma(i), but not by the orthologous gram-positive gene rlma(ii) that methylates the neighboring nucleotide g748. nucleotide g745 interacts ... | 2004 | 15388872 |
| relations and functions of dye-linked formaldehyde dehydrogenase from hyphomicrobium zavarzinii revealed by sequence determination and analysis. | faoa, the gene of the dye-linked nad(p)-independent quinone-containing formaldehyde dehydrogenase of methylamine-grown hyphomicrobium zavarzinii strain zv 580 was sequenced and analyzed together with an apparent promoter region and adjoining genes in a 7.2-kb fragment of hyphomicrobial dna. the formaldehyde dehydrogenase, identified as a periplasmic enzyme by its signal sequence, is distantly related to the soluble pyrroloquinoline-quinone-dependent glucose dehydrogenase of acinetobacter calcoac ... | 2004 | 15480576 |
| diagnosis and assessment of trachoma. | trachoma is caused by chlamydia trachomatis. clinical grading with the who simplified system can be highly repeatable provided graders are adequately trained and standardized. at the community level, rapid assessments are useful for confirming the absence of trachoma but do not determine the magnitude of the problem in communities where trachoma is present. new rapid assessment protocols incorporating techniques for obtaining representative population samples (without census preparation) may giv ... | 2004 | 15489358 |
| antimicrobial susceptibility testing of acinetobacter spp. by nccls broth microdilution and disk diffusion methods. | although both broth microdilution (bmd) and disk diffusion (dd) are listed by nccls as acceptable methods for testing acinetobacter spp. for antimicrobial susceptibility, few studies have compared the results generated by the two methods. we tested 196 isolates of acinetobacter spp. from nine u.s. hospitals and from the centers for disease control culture collection by using bmd and dd and clinically appropriate antimicrobial agents. categorical results for amikacin, ciprofloxacin, gatifloxacin, ... | 2004 | 15528702 |
| wiring of pqq-dehydrogenases. | the performance of pyrroloquinoline quinone (pqq) dependent alcohol dehydrogenase (adh) and two types of pqq-glucose dehydrogenases in solution and when immobilized on the carbon paste electrodes modified with ferrocene derivatives is investigated. the immobilization of adh consisting of pqq and four hemes improves its stability up to 10 times. both pqq and heme moieties are involved in the electron transport from substrate to electrode. the ferrocene derivatives improve the electron transport 1 ... | 2004 | 15556370 |
| synthesis of novel lipids in saccharomyces cerevisiae by heterologous expression of an unspecific bacterial acyltransferase. | the bifunctional wax ester synthase/acyl-coenzyme a:diacylglycerol acyltransferase (ws/dgat) is the key enzyme in storage lipid accumulation in the gram-negative bacterium acinetobacter calcoaceticus adp1, mediating wax ester, and to a lesser extent, triacylglycerol (tag) biosynthesis. saccharomyces cerevisiae accumulates tags and steryl esters as storage lipids. four genes encoding a dgat (dga1p), a phospholipid:diacylglycerol acyltransferase (lro1p) and two acyl-coenzyme a:sterol acyltransfera ... | 2004 | 15574908 |
| quinate oxidation in gluconobacter oxydans ifo3244: purification and characterization of quinoprotein quinate dehydrogenase. | quinoprotein quinate dehydrogenase (qdh) is a membrane-bound enzyme containing pyrroloquinoline quinone (pqq) as the prosthetic group. qdh in gluconobacter oxydans ifo3244 was found to be inducible by quinate and it is not constitutively expressed in the absence of quinate. the purification of holo-form of qdh to nearly homogeneity was achieved. the purified qdh appears to have two subunits of approximately 65 and 21 kda, which could be the result of proteolysis of single polypeptide. kinetic an ... | 2004 | 15598527 |
| identification of an amino acid position that determines the substrate range of integral membrane alkane hydroxylases. | selection experiments and protein engineering were used to identify an amino acid position in integral membrane alkane hydroxylases (ahs) that determines whether long-chain-length alkanes can be hydroxylated by these enzymes. first, substrate range mutants of the pseudomonas putida gpo1 and alcanivorax borkumensis ap1 medium-chain-length ahs were obtained by selection experiments with a specially constructed host. in all mutants able to oxidize alkanes longer than c13, w55 (in the case of p. put ... | 2005 | 15601691 |
| impacts of co-solvent flushing on microbial populations capable of degrading trichloroethylene. | with increased application of co-solvent flushing technologies for removal of nonaqueous phase liquids from groundwater aquifers, concern over the effects of the solvent on native microorganisms and their ability to degrade residual contaminant has also arisen. this study assessed the impact of ethanol flushing on the numbers and activity potentials of trichloroethylene (tce)-degrading microbial populations present in aquifer soils taken immediately after and 2 years after ethanol flushing of a ... | 2005 | 15626648 |
| impacts of co-solvent flushing on microbial populations capable of degrading trichloroethylene. | with increased application of co-solvent flushing technologies for removal of nonaqueous phase liquids from groundwater aquifers, concern over the effects of the solvent on native microorganisms and their ability to degrade residual contaminant has also arisen. this study assessed the impact of ethanol flushing on the numbers and activity potentials of trichloroethylene (tce)-degrading microbial populations present in aquifer soils taken immediately after and 2 years after ethanol flushing of a ... | 2005 | 15626648 |
| [effect of delay of blood cultures on positive detection by automated blood culture system]. | the effect of entry delayed blood culture bottles until the start of incubation for mechanical detection of organism were compared using 2 major blood culture systems; bactec 9240 system and bact/alert 3d system. total of 13 bacterial strains; 5 gram-positive cocci, 7 gram-negative bacilli and candida parapsilosis which were isolated mainly from blood cultures were used as the test strains. bactec 92f, 93f and bact/alert fa, fn bottles were used as the blood culture bottles. all the bottles inoc ... | 2004 | 15628528 |
| [bacterial causes of meningitis in newborns]. | bacterial meningitis jeopardizes the life of affected newborns and in survived children often leaves permanent sequels. the sooner the diagnosis is established and the therapy is started, the more a prosperous outcome can be expected. when the indication is established, lumbar punction should be performed. on the basis of the results of cytological and biochemical analyses of the cerebrospinal fluid (csf) that point to bacterial meningitis, the initial therapy should begin even before the result ... | 2001 | 15637989 |
| manual and automated instrumentation for identification of enterobacteriaceae and other aerobic gram-negative bacilli. | identification of gram-negative bacilli, both enteric and nonenteric, by conventional methods is not realistic for clinical microbiology laboratories performing routine cultures in today's world. the use of commercial kits, either manual or automated, to identify these organisms is a common practice. the advent of rapid or "spot" testing has eliminated the need for some commonly isolated organisms to be identified with the systems approach. commercially available systems provide more in-depth id ... | 2005 | 15653824 |
| mechanism of lipid-body formation in prokaryotes: how bacteria fatten up. | neutral lipid accumulation is frequently observed in some gram-negative prokaryotes like acinetobacter sp. and most actinomycetes, including the pathogenic mycobacterium tuberculosis and antibiotic producing streptomycetes. we examined the formation of wax ester- and triacylglycerol (tag)-bodies in acinetobacter calcoaceticus and rhodococcus opacus using microscopic, immunological and biophysical methods. a general model for prokaryotic lipid-body formation is proposed, clearly differing from th ... | 2005 | 15661001 |
| thio wax ester biosynthesis utilizing the unspecific bifunctional wax ester synthase/acyl coenzyme a:diacylglycerol acyltransferase of acinetobacter sp. strain adp1. | the bifunctional wax ester synthase/acyl coenzyme a (acyl-coa):diacylglycerol acyltransferase (ws/dgat) from acinetobacter sp. strain adp1 (formerly acinetobacter calcoaceticus adp1) mediating the biosyntheses of wax esters and triacylglycerols was used for the in vivo and in vitro biosynthesis of thio wax esters and dithio wax esters. for in vitro biosynthesis, 5'his(6)ws/dgat comprising an n-terminal his(6) tag was purified from the soluble protein fraction of escherichia coli rosetta(de3)plys ... | 2005 | 15691932 |
| physiological conditions conducive to high cyanophycin content in biomass of acinetobacter calcoaceticus strain adp1. | the effects of the inorganic medium components, the initial ph, the incubation temperature, the oxygen supply, the carbon-to-nitrogen ratio, and chloramphenicol on the synthesis of cyanophycin (cgp) by acinetobacter calcoaceticus strain adp1 were studied in a mineral salts medium containing sodium glutamate and ammonium sulfate as carbon and nitrogen sources, respectively. variation of all these factors resulted in maximum cgp contents of only about 3.5% (wt/wt) of the cell dry matter (cdm), and ... | 2005 | 15691941 |
| transcriptional organization of genes for protocatechuate and quinate degradation from acinetobacter sp. strain adp1. | quinate and protocatechuate are both abundant plant products and can serve, along with a large number of other aromatic or hydroaromatic compounds, as growth substrates for acinetobacter sp. strain adp1. the respective genes are part of the chromosomal dca-pca-qui-pob-hca cluster encoding these pathways. the adjacent pca and qui gene clusters, which encode enzymes for protocatechuate breakdown via the beta-ketoadipate pathway and for the conversion of quinate or shikimate to protocatechuate, res ... | 2005 | 15691962 |
| response of biofilm bacteria to dissolved organic matter from decomposing maple leaves. | stream bacteria play an important role in the utilization of dissolved organic matter (dom) leached from leaves, and in transfer of this dom to other trophic levels. leaf leachate is a mixture of labile, recalcitrant, and inhibitory compounds, and bacterial communities vary in their ability to utilize leachate. the purpose of this study was to determine the effects of dom from sugar maple leaves on bacterial populations in biofilms on decomposing leaf surfaces. populations of acinetobacter calco ... | 2004 | 15692852 |
| increasing stability of water-soluble pqq glucose dehydrogenase by increasing hydrophobic interaction at dimeric interface. | water-soluble quinoprotein glucose dehydrogenase (pqqgdh-b) from acinetobacter calcoaceticus has a great potential for application as a glucose sensor constituent. because this enzyme shows no activity in its monomeric form, correct quaternary structure is essential for the formation of active enzyme. we have previously reported on the increasing of the stability of pqqgdh-b by preventing the subunit dissociation. previous studies were based on decreasing the entropy of quaternary structure diss ... | 2005 | 15715904 |
| epr studies of chlorocatechol 1,2-dioxygenase: evidences of iron reduction during catalysis and of the binding of amphipatic molecules. | chlorocatechol 1,2-dioxygenase from pseudomonas putida (pp 1,2-ccd) is a dioxygenase responsible for ring cleavage during the degradation of recalcitrant aromatic compounds. we determined the zero-field splitting of the fe(iii) cofactor (|d| = 1.3 +/- 0.2 cm(-1)) by electron paramagnetic resonance (epr) experiments that along with other structural data allowed us to infer the fe(iii) coordination environment. the epr spectrum of the ion shows a significantly decrease of the g = 4.3 resonance upo ... | 2005 | 15722436 |
| development of a novel glucose enzyme fuel cell system employing protein engineered pqq glucose dehydrogenase. | glucose dehydrogenase harboring pyrroloquinoline quinone as the prosthetic group (pqqgdh) from acinetobacter calcoaceticus is an ideal enzyme for the anode of biofuel cell, because of its oxygen insensitivity and high catalytic efficiency. however, the application of pqqgdh for the bioanode is inherently limited because of its instability. using ser415cys mutant whose stability was greatly improved, we constructed the biofuel cell system employing the engineered pqqgdh as the bioanode enzyme and ... | 2005 | 15741089 |
| quantitative molecular assay for fingerprinting microbial communities of wastewater and estrogen-degrading consortia. | a quantitative fingerprinting method, called the real-time terminal restriction fragment length polymorphism (real-time-t-rflp) assay, was developed for simultaneous determination of microbial diversity and abundance within a complex community. the real-time-t-rflp assay was developed by incorporating the quantitative feature of real-time pcr and the fingerprinting feature of t-rflp analysis. the assay was validated by using a model microbial community containing three pure strains, an escherich ... | 2005 | 15746346 |
| biosorption and recycling of gold using various microorganisms. | in order to obtain basic information on the biosorption and recycling of gold from aqueous systems using microbial cells, the biosorption of gold by various microorganisms was investigated. of 75 strains of microorganisms tested (25 bacteria, 19 actinomycetes, 17 fungi and 14 yeasts), high abilities of gold biosorption from a solution containing hydrogen tetrachloroaurate (iii) were found in some gram-negative bacterial strains, such as acinetobacter calcoaceticus, erwinia herbicola, pseudomonas ... | 2004 | 15754248 |
| detection of and response to signals involved in host-microbe interactions by plant-associated bacteria. | diverse interactions between hosts and microbes are initiated by the detection of host-released chemical signals. detection of these signals leads to altered patterns of gene expression that culminate in specific and adaptive changes in bacterial physiology that are required for these associations. this concept was first demonstrated for the members of the family rhizobiaceae and was later found to apply to many other plant-associated bacteria as well as to microbes that colonize human and anima ... | 2005 | 15755957 |
| alkane-induced expression, substrate binding profile, and immunolocalization of a cytochrome p450 encoded on the nifd excision element of anabaena 7120. | alkanes have been hypothesized to act as universal inducers of bacterial cytochrome p450 gene expression. we tested this hypothesis on an unusual p450 gene (cyp110) found on a conserved 11 kilobase episomal dna element of unknown function found in filamentous cyanobacteria. we also monitored the binding of potential substrates to the p450 protein and explored the distribution of p450 protein in vegetative cells and nitrogen-fixing heterocysts using immuno-electron microscopy. | 2005 | 15790415 |
| [use of claydite-immobilized oil-oxidizing microbial cells for purification of water from oil]. | oil-oxidizing bacteria were isolated from oil-polluted soil and water samples and identified as acinetobacter calcoaceticus k-4, nocardia vaceinii k-8, rhodococcus erythropolis ek-1, and mycobacterium sp. k-2. it was found that immobilization of the bacteria on an expanded clay aggregate accelerated their growth and consumption of hydrocarbon substrates. it was also found that water polluted with 100 mg/l oil could be purified with rhodococcus erythropolis ek-1 and nocardia vaceinii k-8 cells im ... | 2005 | 15810734 |
| biocatalytic production of perillyl alcohol from limonene by using a novel mycobacterium sp. cytochrome p450 alkane hydroxylase expressed in pseudomonas putida. | a number of oxygenated monoterpenes present at low concentrations in plant oils have anticarcinogenic properties. one of the most promising compounds in this respect is (-)-perillyl alcohol. since this natural product is present only at low levels in a few plant oils, an alternative, synthetic source is desirable. screening of 1,800 bacterial strains showed that many alkane degraders were able to specifically hydroxylate l-limonene in the 7 position to produce enantiopure (-)-perillyl alcohol. t ... | 2005 | 15811996 |
| formation of trans fatty acids is not involved in growth-linked membrane adaptation of pseudomonas putida. | fatty acid compositions in growing and resting cells of several strains of pseudomonas putida (p8, nctc 10936, and kt 2440) were studied, with a focus on alterations of the saturation degree, cis-trans isomerization, and cyclopropane formation. the fatty acid compositions of the strains were very similar under comparable growth conditions, but surprisingly, and contrary to earlier reports, trans fatty acids were not found in either exponentially growing cells or stationary-phase cells. during th ... | 2005 | 15812020 |
| species-level identification of isolates of the acinetobacter calcoaceticus-acinetobacter baumannii complex by sequence analysis of the 16s-23s rrna gene spacer region. | the species acinetobacter calcoaceticus, a. baumannii, genomic species 3, and genomic species 13tu included in the acinetobacter calcoaceticus-acinetobacter baumannii complex are genetically highly related and difficult to distinguish phenotypically. except for a. calcoaceticus, they are all important nosocomial species. in the present study, the usefulness of the 16s-23s rrna gene intergenic spacer (its) sequence for the differentiation of (genomic) species in the a. calcoaceticus-a. baumannii ... | 2005 | 15814977 |
| sulfoacetaldehyde is excreted quantitatively by acinetobacter calcoaceticus sw1 during growth with taurine as sole source of nitrogen. | eighteen enrichment cultures with taurine (2-aminoethanesulfonate) as the sole source of combined nitrogen under aerobic conditions were all successful, and 24 pure cultures were obtained. only three of the cultures yielded an inorganic product, sulfate, from the sulfonate moiety of taurine, and the others were presumed to yield organosulfonates. sulfoacetate, known from rhodopseudomonas palustris cga009 under these conditions, was not detected in any culture, but sulfoacetaldehyde (as a hydrazo ... | 2005 | 15817795 |
| structural modifications and antimicrobial activity of n-cycloalkenyl-2-acylalkylidene-2,3-dihydro-1,3-benzothiazoles. | a series of n-cycloalkenyl-2-acylalkylidene-2,3-dihydro-1,3-benzothiazoles 5a-j, n-cycloalkyl-2-acylalkylidene-2,3-dihydro-1,3-benzothiazoles 8a-e, and n-alkyl-2-acylalkylidene-2,3-dihydro-1,3-benzothiazoles 8f-h, were synthesized and tested for in vitro antibacterial and antifungal activities against four gram-positive and five gram-negative bacteria (bacillus subtilis 6633, enterococcus faecalis 29212, staphylococcus aureus 6538, staphylococcus aureus 25923, escherichia coli 25922, acinetobact ... | 2005 | 15848203 |
| changes in antibiotic resistance of the most common gram-negative bacteria isolated in intensive care units. | we studied the changes in antibiotic resistance of the most common gram-negative bacteria isolated in the intensive care units at our hospital in 2000 and 2002. bacterial identification was performed by use of the vitek 60 analyser, and antibiotic susceptibilities were tested by the vitek 60 analyser and the disk diffusion agar method. the bacteria isolated most frequently were pseudomonas aeruginosa (132 strains in 2000 and 106 in 2002), acinetobacter calcoaceticus (98 and 109 strains, respecti ... | 2005 | 15890431 |
| catabolism of benzoate and phthalate in rhodococcus sp. strain rha1: redundancies and convergence. | genomic and proteomic approaches were used to investigate phthalate and benzoate catabolism in rhodococcus sp. strain rha1, a polychlorinated biphenyl-degrading actinomycete. sequence analyses identified genes involved in the catabolism of benzoate (ben) and phthalate (pad), the uptake of phthalate (pat), and two branches of the beta-ketoadipate pathway (catrabc and pcajihgblfr). the regulatory and structural ben genes are separated by genes encoding a cytochrome p450. the pad and pat genes are ... | 2005 | 15937168 |
| gene conversion tracts associated with crossovers in rhizobium etli. | gene conversion has been defined as the nonreciprocal transfer of information between homologous sequences. despite its broad interest for genome evolution, the occurrence of this mechanism in bacteria has been difficult to ascertain due to the possible occurrence of multiple crossover events that would mimic gene conversion. in this work, we employ a novel system, based on cointegrate formation, to isolate gene conversion events associated with crossovers in the nitrogen-fixing bacterium rhizob ... | 2005 | 15937174 |
| real-time monitoring of enzymatic dna hydrolysis by electrospray ionization mass spectrometry. | a fast and direct method for the monitoring of enzymatic dna hydrolysis was developed using electrospray ionization mass spectrometry. we incorporated the use of a robotic chip-based electrospray ionization source for increased reproducibility and throughput. the mass spectrometry method allows the detection of dna fragments and intact non-covalent protein-dna complexes in a single experiment. we used the method to monitor in real-time single-stranded (ss) dna hydrolysis by colicin e9 dnase and ... | 2005 | 15956101 |
| worldwide disseminated arma aminoglycoside resistance methylase gene is borne by composite transposon tn1548. | the arma (aminoglycoside resistance methylase) gene, which confers resistance to 4,6-disubstituted deoxystreptamines and fortimicin, was initially found in klebsiella pneumoniae bm4536 on incl/m plasmid pip1204 of ca. 90 kb which also encodes the extended-spectrum beta-lactamase ctx-m-3. thirty-four enterobacteria from various countries that were likely to produce a ctx-m enzyme since they were more resistant to cefotaxime than to ceftazidime were studied. the arma gene was detected in 12 clinic ... | 2005 | 15980373 |
| degradation of cyanophycin by sedimentibacter hongkongensis strain ki and citrobacter amalonaticus strain g isolated from an anaerobic bacterial consortium. | using a combination of various enrichment techniques, the strictly anaerobic, gram-positive, endospore-forming bacterium sedimentibacter hongkongensis strain ki as revealed by 16s rrna analysis and the gram-negative enterobacterium citrobacter amalonaticus strain g as revealed by physiological tests were isolated from an anaerobic cyanophycin (cgp)-degrading bacterial consortium. s. hongkongensis strain ki is the first anaerobic bacterium with the ability to hydrolyze cgp to beta-asp-arg and bet ... | 2005 | 16000772 |
| abundance of three bacterial populations in selected streams. | the population sizes of three bacterial species, acinetobacter calcoaceticus, burkholderia cepacia, and pseudomonas putida, were examined in water and sediment from nine streams in different parts of the united states using fluorescent in situ hybridization (fish). population sizes were determined from three sites (upstream, midstream, and downstream) in each stream to compare differences in the occurrence and distribution of the species within each stream and among streams. physical and chemica ... | 2005 | 16003475 |
| spleen and lung involvement by acinetobacter calcoaceticus bacteremia mimicking deep fungal infection in a child with acute non-lymphoblastic leukemia. | | 2006 | 16078222 |
| multidrug-resistant acinetobacter extremity infections in soldiers. | war wound infection and osteomyelitis caused by multidrug-resistant (mdr) acinetobacter species have been prevalent during the 2003-2005 military operations in iraq. twenty-three soldiers wounded in iraq and subsequently admitted to our facility from march 2003 to may 2004 had wound cultures positive for acinetobacter calcoaceticus-baumannii complex. eighteen had osteomyelitis, 2 burn infection, and 3 deep wound infection. primary therapy for these infections was directed antimicrobial agents fo ... | 2005 | 16102310 |
| streptomyces pharetrae sp. nov., isolated from soil from the semi-arid karoo region. | an actinomycete, strain cza14t, was isolated from worcester in the western cape province of south africa. based on rapid genus identification, 16s-rdna sequence similarities and chemotaxonomy, strain cza14t was identified as a member of the genus streptomyces. it exhibited weak antibiosis against bacillus coagulans atcc 7050t, mycobacterium aurum a+ and acinetobacter calcoaceticus c91. the results of physiological tests and analysis of the 16s-rdna sequence allowed for the differentiation of str ... | 2005 | 16104349 |
| development of a multilocus sequence typing scheme for characterization of clinical isolates of acinetobacter baumannii. | in this study a multilocus sequence typing (mlst) scheme for acinetobacter baumannii was developed and evaluated by using 40 clinical a. baumannii isolates recovered from outbreaks in spanish and german hospitals during the years 1990 to 2001, as well as isolates from other european hospitals and two dsmz reference strains of a. baumannii. for comparison, two isolates of acinetobacter species 13 (sensu tjernberg and ursing), two clinical isolates, and three dsmz strains of a. calcoaceticus (both ... | 2005 | 16145081 |
| constitutive expression of catabc genes in the aniline-assimilating bacterium rhodococcus species an-22: production, purification, characterization and gene analysis of cata, catb and catc. | the aniline-assimilating bacterium rhodococcus sp. an-22 was found to constitutively synthesize catb (cis,cis-muconate cycloisomerase) and catc (muconolactone isomerase) in its cells growing on non-aromatic substrates, in addition to the previously reported cata (catechol 1,2-dioxygenase). the bacterium maintained the specific activity of the three enzymes at an almost equal level during cultivation on succinate. catb and catc were purified to homogeneity and characterized. catb was a monomer wi ... | 2006 | 16156722 |
| constitutive expression of catabc genes in the aniline-assimilating bacterium rhodococcus species an-22: production, purification, characterization and gene analysis of cata, catb and catc. | the aniline-assimilating bacterium rhodococcus sp. an-22 was found to constitutively synthesize catb (cis,cis-muconate cycloisomerase) and catc (muconolactone isomerase) in its cells growing on non-aromatic substrates, in addition to the previously reported cata (catechol 1,2-dioxygenase). the bacterium maintained the specific activity of the three enzymes at an almost equal level during cultivation on succinate. catb and catc were purified to homogeneity and characterized. catb was a monomer wi ... | 2006 | 16156722 |
| microscale process evaluation of recombinant biocatalyst libraries: application to baeyer-villiger monooxygenase catalysed lactone synthesis. | microscale processing techniques are rapidly emerging as a cost- effective means for parallel experimentation and hence the evaluation of large libraries of recombinant biocatalysts. in this work, the potential of an automated microscale process is demonstrated in a linked sequence of operations comprising fermentation, enzyme induction and bioconversion using three whole-cell biocatalysts each expressing cyclohexanone monoxygenase (chmo). the biocatalysts, escherichia coli top 10 [pqr239], e. c ... | 2005 | 16208497 |
| biological modification of the fatty acid group in an emulsan by supplementing fatty acids under conditions inhibiting fatty acid biosynthesis. | when the concentration of the antibiotic cerulenin was increased up to 3.0 mg/l in medium containing ethanol as a carbon source, the specific growth rate of acinetobacter calcoaceticus and the fatty acid content of the emulsan decreased from 0.179 h(-1) and 13.9% to 0.015 h(-1) and 3.4%, respectively. the emulsifying activity in medium containing cerulenin decreased with increasing cerulenin concentration. in the culture containing 3.0 mg/l cerulenin, fatty acid biosynthesis was inhibited. vario ... | 2000 | 16232861 |
| cloning and sequence analysis of the esta gene encoding enzyme for producing (r)-beta-acetylmercaptoisobutyric acid from pseudomonas aeruginosa 1001. | the esta gene encoding the enzyme that catalyzes the production of (r)-beta-acetylmercaptoisobutyric acid from (r,s)-ester from pseudomonas aeruginosa 1001, was cloned in escherichia coli and its nucleotide sequence was determined, revealing the presumed open reading frame encoding a polypeptide of 316 amino acid residues (948 nucleotides). the overall a + t and c + g compositions were 32.59% and 67.41%, respectively. the amino acid sequence of the esta gene product showed a significant similari ... | 2000 | 16232934 |
| competitive growth of gordonia and acinetobacter in continuous flow aerobic and anaerobic/aerobic reactors. | gordonia amarae and acinetobacter calcoaceticus pure culture experiments were conducted in continuous flow chemostats fed with an acetate/mineral salts medium under aerobic and anaerobic-aerobic conditions. the growth parameters such as volatile suspended solids (vss) suggest that acinetobacter can successfully out-compete gordonia under both aerobic and anaerobic-aerobic conditions when both are present in a dual culture. gordonia was reduced to near detection limits (<10 mg vss/1), while acine ... | 2003 | 16233460 |
| a unique polypeptide from the c-terminus of the exocellular esterase of acinetobacter venetianus rag-1 modulates the emulsifying activity of the polymeric bioemulsifier apoemulsan. | an exocellular esterase from the oil-degrading acinetobacter venetianus rag-1 was previously shown to enhance the emulsification and emulsion stabilization properties of the amphipathic, aminopolysaccharide bioemulsifier, emulsan [bach h, berdichevsky y, gutnick d (2003) an exocellular protein from the oil-degrading microbe acinetobacter venetianus rag-1 enhances the emulsifying activity of the polymeric bioemulsifier emulsan. appl environ microbiol 69:2608-15]. this enhancement was specific for ... | 2006 | 16237525 |
| isolation and characterization of a phenol-degrading bacterium from an industrial activated sludge. | this paper reports the successful isolation and characterization of a new phenol-degrading bacterium, strain edp3, from activated sludge. strain edp3 is a nonmotile, strictly aerobic, gram-negative, and short-rod or coccobacillary bacterium, which occurs singly, in pairs, or in clusters. 16s rrna gene sequence analysis revealed that strain edp3 belonged to the gamma group of proteobacteria, with a 97.0% identity to 16s rrna gene sequences of acinetobacter calcoaceticus. strain edp3 could aerobic ... | 2006 | 16283294 |
| fluoroquinolone resistance from a transferable plasmid in acinetobacter calcoaceticus. | | 2004 | 16295408 |
| effect of activated sludge properties and membrane operation conditions on fouling characteristics in membrane bioreactors. | biofouling control is considered to be a major challenge in operating membrane bioreactors (mbrs) for the treatment of wastewater. this study examined the impact of biological, chemical, and physical properties of activated sludge on membrane filtration performance in laboratory-scale mbrs. sludges with different microbial communities were produced using pseudo-continuous stirred-tank reactors and pseudo-plug flow reactors treating a synthetic paper mill wastewater. various filtration resistance ... | 2006 | 16307781 |
| stereoselective esterase from pseudomonas putida ifo12996 reveals alpha/beta hydrolase folds for d-beta-acetylthioisobutyric acid synthesis. | esterase (est) from pseudomonas putida ifo12996 catalyzes the stereoselective hydrolysis of methyl dl-beta-acetylthioisobutyrate (dl-mati) to produce d-beta-acetylthioisobutyric acid (dat), serving as a key intermediate for the synthesis of angiotensin-converting enzyme inhibitors. the est gene was cloned and expressed in escherichia coli; the recombinant protein is a non-disulfide-linked homotrimer with a monomer molecular weight of 33,000 in both solution and crystalline states, indicating tha ... | 2005 | 16321951 |
| protamylasse, a residual compound of industrial starch production, provides a suitable medium for large-scale cyanophycin production. | protamylasse is a residual compound occurring during the industrial production of starch from potatoes. it contains a variety of nutrients and all necessary minerals and could be used as a carbon, nitrogen, and energy source for the growth of bacteria and also for cyanophycin (cgp) biosynthesis. media containing protamylasse as the sole compound diluted only in water were therefore examined for their suitability in cgp production. among various bacterial strains investigated in this study, a rec ... | 2005 | 16332748 |
| detection and isolation of ultrasmall microorganisms from a 120,000-year-old greenland glacier ice core. | the abundant microbial population in a 3,043-m-deep greenland glacier ice core was dominated by ultrasmall cells (<0.1 microm3) that may represent intrinsically small organisms or starved, minute forms of normal-sized microbes. in order to examine their diversity and obtain isolates, we enriched for ultrasmall psychrophiles by filtering melted ice through filters with different pore sizes, inoculating anaerobic low-nutrient liquid media, and performing successive rounds of filtrations and recult ... | 2005 | 16332755 |
| hydroxylation of the herbicide isoproturon by fungi isolated from agricultural soil. | several asco-, basidio-, and zygomycetes isolated from an agricultural field were shown to be able to hydroxylate the phenylurea herbicide isoproturon [n-(4-isopropylphenyl)-n',n'-dimethylurea] to n-(4-(2-hydroxy-1-methylethyl)phenyl)-n',n'-dimethylurea and n-(4-(1-hydroxy-1-methylethyl)phenyl)-n',n'-dimethylurea. bacterial metabolism of isoproturon has previously been shown to proceed by an initial demethylation to n-(4-isopropylphenyl)-n'-methylurea. in soils, however, hydroxylated metabolites ... | 2005 | 16332769 |
| cell surface measurements in hydrocarbon and carbohydrate fermentations. | acinetobacter calcoaceticus was grown in 11-liter batch fermentations with hexadecane or sodium citrate as the sole source of carbon. surface and interfacial tension measurements of the microbial broth indicated that surface-active compounds were being produced only during growth on the hydrocarbon substrate. contact angle measurements of an aqueous drop on a smooth lawn of cells in a hexadecane bath indicated a highly hydrophobic surface of the cells in the initial stages of the hydrocarbon fer ... | 1980 | 16345526 |
| membrane filter method for enumeration of acinetobacter calcoaceticus from environmental waters. | a membrane filter method was developed and evaluated for the quantitative recovery of acinetobacter calcoaceticus from environmental waters. the procedure utilized a mineral medium, with sodium acetate and potassium nitrate as the carbon and nitrogen sources, respectively. formic acid was included to enhance the recovery of a. calcoaceticus and to inhibit background growth. the medium was incubated for 46 h at 30 degrees c, after which fermentation and cytochrome oxidase tests were performed on ... | 1982 | 16345933 |
| emulsan in acinetobacter calcoaceticus rag-1: distribution of cell-free and cell-associated cross-reacting material. | emulsan is an extracellular polymeric bioemulsifier produced by acinetobacter calcoaceticus rag-1. antibodies prepared against purified emulsan inhibited the activity of the polymer in a standard emulsification test. these antibodies were used to develop a sensitive enzyme-linked immunosorbent assay to monitor changes in cell-free emulsan throughout the growth cycle. this assay was also used to detect emulsan associated with the cell surface and to monitor changes in the distribution of cell-fre ... | 1982 | 16346052 |
| role of thin fimbriae in adherence and growth of acinetobacter calcoaceticus rag-1 on hexadecane. | acinetobacter calcoaceticus rag-1, a hydrocarbon-degrading bacterium which adheres avidly to hydrocarbons and other hydrophobic surfaces, possesses numerous thin fimbriae (ca. 3.5-nm diameter) on the cell surface. mr-481, a nonadherent mutant of rag-1 which is unable to grow on hexadecane under conditions of limited emulsification and low initial cell density, lacks these fimbriae. prolonged incubation of mr-481 in hexadecane medium enriched for partial adherence revertants. the reappearance of ... | 1982 | 16346118 |
| exopolysaccharide distribution of and bioemulsifier production by acinetobacter calcoaceticus bd4 and bd413. | the heavily encapsulated acinetobacter calcoaceticus bd4 and the "miniencapsulated" single-step mutant a. calcoaceticus bd413 produced extracellular polysaccharides in addition to the capsular material. the molar ratio of rhamnose to glucose (3:1) in the extracellular bd413 polysaccharide fraction was similar to the composition of the capsular material. in both strains, the increase in capsular polysaccharide was parallel to cell growth and remained constant in stationary phase. the extracellula ... | 1982 | 16346151 |
| degradation of the herbicide mecoprop [2-(2-methyl-4-chlorophenoxy)propionic acid] by a synergistic microbial community. | a microbial community isolated from wheat root systems was capable of growth on mecoprop as the sole carbon and energy source. when exposed to fresh herbicide additions, the community was able to shorten the lag phase from 30 days to less than 24 h. the community comprised two pseudomonas species, an alcaligenes species, a flavobacterium species, and acinetobacter calcoaceticus. none of the pure cultures was capable of growing on mecoprop. certain combinations of two or more community constituen ... | 1985 | 16346731 |
| role for emulsan in growth of acinetobacter calcoaceticus rag-1 on crude oil. | when acinetobacter calcoaceticus rag-1 was grown together with an emulsan-deficient mutant on crude oil, only the emulsan-producing rag-1 was found to grow, regardless of whether the medium was supplemented with emulsan. the results suggested that the cell-associated form of the bioemulsifier is the biologically active species required for growth on crude oil. a revertant of an emulsan-deficient strain was isolated which simultaneously regained the ability to produce both cell-associated and cel ... | 1986 | 16347027 |
| microbiological degradation of malodorous substances of swine waste under aerobic conditions. | phenol, p-cresol, and volatile fatty acids (vfa; acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids) were used as odor indicators of swine waste. aeration of the waste allowed the indigenous microorganisms to grow and degrade these malodorous substances. the time required for degradation of these substances varied according to the waste used, and it was not necessarily related to their concentrations. using a minimal medium which contained one of the malodorous compounds as so ... | 1987 | 16347254 |
| production of biodispersan by acinetobacter calcoaceticus a2. | bacterial strains a2 and he5, isolated by enrichment culture techniques, were shown to produce extracellular, nondialyzable materials which disperse limestone powders in water. these materials are referred to as biodispersans. strains a2 and he5 were classified as acinetobacter calcoaceticus by physiological and genetic tests. an assay for limestone-dispersing activity was developed which is based on the settling time of a standard 10% limestone-in-water mixture. the assay was proportional to bi ... | 1988 | 16347544 |
| purification and chemical properties of acinetobacter calcoaceticus a2 biodispersan. | the extracellular dispersant of acinetobacter calcoaceticus a2, referred to as biodispersan, was concentrated by ammonium sulfate precipitation and deproteinized by hot phenol treatment. the active component was an anionic polysaccharide (ps-a2). the specific activity of ps-a2 was approximately three times greater than that of crude biodispersan. ps-a2 had a sedimentation constant of 1.39 s, a diffusion coefficient of 18.8 x 10 cm s, and a partial molar volume of 0.65 cm g, yielding an average m ... | 1988 | 16347545 |
| effect of emulsan on biodegradation of crude oil by pure and mixed bacterial cultures. | crude oil was treated with purified emulsan, the heteropolysaccharide bioemulsifier produced by acinetobacter calcoaceticus rag-1. a mixed bacterial population as well as nine different pure cultures isolated from various sources was tested for biodegradation of emulsan-treated and untreated crude oil. biodegradation was measured both quantitatively and qualitatively. recovery of co(2) from mineralized c-labeled substrates yielded quantitative data on degradation of specific compounds, and capil ... | 1989 | 16347832 |