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PubMed1995

Genomic species typing of acinetobacters by polymerase chain reaction amplification of the recA gene.

The recA gene has been used as a target in screening for the presence of acinetobacters on the genospecies level and differentiation of relevant acinetobacter species from one another by PCR. Primers deduced from known recA gene sequences of Acinetobacter calcoaceticus and Neisseria gonorrhoeae allowed the amplification of DNAs from all Acinetobacter genospecies. The size of the amplified DNA fragment from all genospecies tested was approximately 435-500 bp relative to DNA size markers. The amplified products were examined further by restriction fragment length polymorphism (RFLP) analysis. Restriction analysis with only two enzymes, MboI and HinfI, enabled us to identify all known genospecies. Since this method uses conserved recA gene sequences for primers, it is expected to be applicable for the identification of most bacterial species.

Acinetobacter↗
PubMed1993

Characterization of Acinetobacter haemolyticus aac(6')-Ig gene encoding an aminoglycoside 6'-N-acetyltransferase which modifies amikacin.

The amikacin resistance gene acc(6')-Ig of Acinetobacter haemolyticus BM2685 encoding an aminoglycoside 6'-N-acetyltransferase was characterized. The gene was identified as a coding sequence of 438 bp corresponding to a protein with a calculated mass of 16,522 Da. Analysis of the deduced amino acid sequence suggested that it was the fourth member of a subfamily of aminoglycoside 6'-N-acetyltransferases. The resistance gene was not transferable either by conjugation to Escherichia coli or to Acinetobacter baumannii or by transformation into Acinetobacter calcoaceticus. Plasmid DNA from strain BM2685 did not hybridize with an intragenic aac(6')-Ig probe. These results suggest a chromosomal location for this gene. The gene was detected by DNA hybridization in all 20 strains of A. haemolyticus tested but not in 179 other Acinetobacter strains, including A. baumannii, A. lwoffii, A. junii, and A. johnsonii and genospecies 3, 6, 11, 13, 14, 15, 16, and 17, of which 162 were amikacin resistant. The probe did not hybridize in dot blot assays with DNAs purified from members of the families Enterobacteriaceae and Pseudomonadaceae that encode 6'-N-acetyltransferases. These data suggest that the aac(6')-Ig gene is species specific and may be used to identify A. haemolyticus.

Acetyltransferases↗
PubMed1989

Polyphosphate-degrading enzymes in Acinetobacter spp. and activated sludge.

Polyphosphate-degrading enzymes were studied in Acinetobacter spp. and activated sludge. Polyphosphate: AMP phosphotransferase activity in Acinetobacter strain 210A decreased with increasing growth rates. The activity of this enzyme in cell extracts of Acinetobacter strain 210A was maximal at a pH of 8.5 and a temperature of 40 degrees C and was stimulated by (NH4)2SO4. The Km for AMP was 0.6 mM, and the Vmax was 60 nmol/min per mg of protein. Cell extracts of this strain also contained polyphosphatase, which was able to degrade native polyphosphate and synthetic magnesium polyphosphate and was strongly stimulated by 300 to 400 mM NH4Cl. A positive correlation was found between polyphosphate:AMP phosphotransferase activity, adenylate kinase activity, and phosphorus accumulation in six Acinetobacter strains. Significant activities of polyphosphate kinase were detected only in strain P, which contained no polyphosphate:AMP phosphotransferase. In samples of activated sludge from different plants, the activity of adenylate kinase correlated well with the ability of the sludge to remove phosphate biologically from wastewater.

Acid Anhydride Hydrolases↗
PubMed1991

Analysis of the polyphosphate-accumulating microflora in phosphorus-eliminating, anaerobic-aerobic activated sludge systems by using diaminopropane as a biomarker for rapid estimation of Acinetobacter spp.

Polyphosphate-accumulating gram-negative bacteria were isolated from different anaerobic-aerobic activated sludge systems with diverse processes for enhanced biological phosphorus (P) elimination. Of 22 isolates, 10 were allocated to the genus Acinetobacter by using multiple-test systems and soluble protein and polyamine patterns. As diaminopropane (DAP) appears to be the characteristic main polyamine compound produced by Acinetobacter spp., it was used as a biomarker for the genus. The high DAP contents of representative samples from municipal wastes with enhanced biological P elimination indicated that Acinetobacter spp. can be dominant organisms in sewage treatment plants with low organic loading and nitrification and denitrification steps. Contrary to accepted opinion, sludge from treatment plants with efficient P removal and high organic loading had a low DAP content, indicating that bacteria other than Acinetobacter spp. are responsible for enhanced biological P elimination in these plants.

Acinetobacter↗
PubMed2004

Toxicity caused by hydroxycinnamoyl-coenzyme A thioester accumulation in mutants of Acinetobacter sp. strain ADP1.

Hydroxycinnamates, aromatic compounds that play diverse roles in plants, are dissimilated by enzymes encoded by the hca genes in the nutritionally versatile, naturally transformable bacterium Acinetobacter sp. strain ADP1. A key step in the hca-encoded pathway is activation of the natural substrates caffeate, p-coumarate, and ferulate by an acyl:coenzyme A (acyl:CoA) ligase encoded by hcaC. As described in this paper, Acinetobacter cells with a knockout of the next enzyme in the pathway, hydroxycinnamoyl-CoA hydratase/lyase (HcaA), are extremely sensitive to the presence of the three natural hydroxycinnamate substrates; Escherichia coli cells carrying a subclone with the hcaC gene are hydroxycinnamate sensitive as well. When the hcaA mutation was combined with a mutation in the repressor HcaR, exposure of the doubly mutated Acinetobacter cells to caffeate, p-coumarate, or ferulate at 10(-6) M totally inhibited the growth of cells. The toxicity of p-coumarate and ferulate to a DeltahcaA strain was found to be a bacteriostatic effect. Although not toxic to wild-type cells initially, the diphenolic caffeate was itself converted to a toxin over time in the absence of cells; the converted toxin was bactericidal. In an Acinetobacter strain blocked in hcaA, a secondary mutation in the ligase (HcaC) suppresses the toxic effect. Analysis of suppression due to the mutation of hcaC led to the development of a positive-selection strategy that targets mutations blocking HcaC. An hcaC mutation from one isolate was characterized and was found to result in the substitution of an amino acid that is conserved in a functionally characterized homolog of HcaC.

Acinetobacter↗
PubMed2005

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)pLysS (pET23a::5'His(6)atf). By employing SP-Sepharose high-pressure and Ni-nitrilotriacetic acid fast-protein liquid chromatographies, a 19-fold enrichment with a final specific activity of 165.2 nmol mg of protein(-1) min(-1) was achieved by using 1-hexadecanol and palmitoyl-CoA as substrates. Incubation of purified 5'His(6)WS/DGAT with 1-hexadecanethiol and palmitoyl-CoA as substrates resulted in the formation of palmitic acid hexadecyl thio ester (10.4% relative specific activity of a 1-hexadecanol control). Utilization of 1,8-octanedithiol and palmitoyl-CoA as substrates led to the formation of 1-S-monopalmitoyloctanedithiol and minor amounts of 1,8-S-dipalmitoyloctanedithiol (59.3% relative specific activity of a 1-hexadecanol control). The latter dithio wax ester was efficiently produced when 1-S-monopalmitoyloctanedithiol and palmitoyl-CoA were used as substrates (13.4% specific activity relative to that of a 1-hexadecanol control). For the in vivo biosynthesis of thio wax esters, the knockout mutant Acinetobacter sp. strain ADP1acr1OmegaKm, which is unable to produce fatty alcohols, was used. Cultivation of Acinetobacter sp. strain ADP1acr1OmegaKm in the presence of gluconate, 1-hexadecanethiol, and oleic acid in nitrogen-limited mineral salts medium resulted in the accumulation of unusual thio wax esters that accounted for around 1.19% (wt/wt) of the cellular dry weight and consisted mainly of oleic acid hexadecyl thioester as revealed by gas chromatography-mass spectrometry.

Acinetobacter↗
PubMed2006

Engineering the genotype of Acinetobacter sp. strain ADP1 to enhance biosynthesis of cyanophycin.

To study the importance of arginine provision and phosphate limitation for synthesis and accumulation of cyanophycin (CGP) in Acinetobacter sp. strain ADP1, genes encoding the putative arginine regulatory protein (argR) and the arginine succinyltransferase (astA) were inactivated, and the effects of these mutations on CGP synthesis were analyzed. The inactivation of these genes resulted in a 3.5- or 7-fold increase in CGP content, respectively, when the cells were grown on glutamate. Knockout mutations in both genes led to a better understanding of the effect of the addition of other substrates to arginine on CGP synthesis during growth of the cells of Acinetobacter sp. strain ADP1. Overexpression of ArgF (ornithine carbamoyltransferase), CarA-CarB (small and large subunits of carbamoylphosphate synthetase), and PepC (phosphoenolpyruvate carboxylase) triggered synthesis of CGP if amino acids were used as a carbon source whereas it was not triggered by gluconate or other sugars. Cells of Acinetobacter sp. strain ADP1, which is largely lacking genes for carbohydrate metabolism, showed a significant increase in CGP contents when grown on mineral medium supplemented with glutamate, aspartate, or arginine. The Acinetobacter sp. DeltaastA(pYargF) strain is unable to utilize arginine but synthesizes more arginine, resulting in CGP contents as high as 30% and 25% of cell dry matter when grown on protamylasse or Luria-Bertani medium, respectively. This recombinant strain overcame the bottleneck of the costly arginine provision where it produces about 75% of the CGP obtained from the parent cells grown on mineral medium containing pure arginine as the sole source of carbon. Phosphate starvation is the only known trigger for CGP synthesis in this bacterium, which possesses the PhoB/PhoR phosphate regulon system. Overexpression of phoB caused an 8.6-fold increase in CGP content in comparison to the parent strain at a nonlimiting phosphate concentration.

Acinetobacter↗
PubMed1974

Clinical studies on a transformation test for identification of Acinetobacter (Mima and Herellea).

Deoxyribonucleic acid (DNA) from 250 strains of aerobic, nonfermentative, gram-negative coccobacilli and rods were tested for the ability to transform a stable competent auxotroph of Acinetobacter (strain trp E 27) to prototrophy by using the method established by Juni. Several modifications of Juni's original procedure were made to adapt it for use in a clinical diagnostic laboratory. These modifications were directed primarily towards shortening the procedure to allow completion in a time framework consistent with current procedures. The modifications included changes in sterilization temperature, incubation time and temperature of the competent auxotroph and DNA preparation, overnight incubation temperature, and variations in the age of the auxotroph culture when used. Under these conditions, the transformation can easily be performed in 24 h, the final 16 to 18 h being an overnight uninterrupted incubation period. When used in conjunction with the glucose oxidative fermentative basal metabolism test, it provided a rapid highly efficient means for grouping and identifying acinetobacters which is far superior to a biochemical schema. Without exception, the 141 strains of DNA from Acinetobacter species were able to transform the auxotroph to prototrophy. None of the 105 oxidase-positive nonfermenters possessed DNA which was able to transform the Acinetobacter auxotroph to prototrophy.

Acinetobacter↗
PubMed2001

Functions of the mismatch repair gene mutS from Acinetobacter sp. strain ADP1.

The genus Acinetobacter encompasses a heterogeneous group of bacteria that are ubiquitous in the natural environment due in part to their ability to adapt genetically to novel challenges. Acinetobacter sp. strain ADP1 (also known as strain BD413) is naturally transformable and takes up DNA from any source. Donor DNA can be integrated into the chromosome by recombination provided it possesses sufficient levels of nucleotide sequence identity to the recipient's DNA. In other bacteria, the requirement for sequence identity during recombination is partly due to the actions of the mismatch repair system, a key component of which, MutS, recognizes mismatched bases in heteroduplex DNA and, along with MutL, blocks strand exchange. We have cloned mutS from strain ADP1 and examined its roles in preventing recombination between divergent DNA and in the repair of spontaneous replication errors. Inactivation of mutS resulted in 3- to 17-fold increases in transformation efficiencies with donor sequences that were 8 to 20% divergent relative to the strain ADP1. Strains lacking MutS exhibited increased spontaneous mutation frequencies, and reversion assays demonstrated that MutS preferentially recognized transition mismatches while having little effect on the repair of transversion mismatches. Inactivation of mutS also abolished the marker-specific variations in transforming efficiency seen in mutS(+) recipients where transition and frameshift alleles transformed at eightfold lower frequencies than transversions or large deletions. Comparison of the MutS homologs from five individual Acinetobacter strains with those of other gram-negative bacteria revealed that a number of unique indels are conserved among the Acinetobacter amino acid sequences.

Acinetobacter↗
PubMed1975

Partial purification and characterization of the lipase of a facultatively psychrophilic bacterium (Acinetobacter O16).

The extracellular lipase(s) of the psychrophile Acinetobacter O16 was studied. When the enzyme was precipitated by (NH4)2SO4 and passed through a Sephadex G200 column, two peaks of lipase activity appeared. The larger peak, which behaved like a substance of high molecular weight, being eluted in the void volume, was purified 250-fold over the crude enzyme (culture supernatant) by passage through a DEAE-Sephadex column. When the enzyme was applied to a DEAE-cellulose column it could not be eluted unless it had first been treated with the detergent Titon X 100. It is suggested that lipids or phospholipids make up an important part of the molecule. The activity of the crude and partly purified enzymes was studied in relation to pH and temperature optima. Lipases from the psychrophilic Acinetobacter O16 and from the mesophilic Acinetobacter O4 reacted in the same way to temperature. The crude enzyme from Acinetobacter O16 was more temperature-stable than the purified enzyme.

Acinetobacter↗
PubMed1980

A comparison of the citrate synthases of Escherichia coli and Acinetobacter anitratum.

Citrate synthase has been purified to homogeneity from a strain of the Gram-negative aerobic bacterium Acinetobacter anitratum in a form which retains its sensitivity to the allosteric inhibitor NADH. In subunit size, amino acid composition, and antigenic reactivity the enzyme shows a marked structural resemblance to the citrate synthase of the Gram-negative facultative anaerobe Escherichia coli. Whereas the E. coli enzyme is subject to a strong, hyperbolic inhibition by NADH (Hill's number n = 1.0, Ki = 2 microM), the A. anitratum enzyme shows a weak, sigmoid response (n = 1.6, I0.5 = 140 microM) to this nucleotide. With E. coli, NADH inhibition is competitive with acetyl-CoA, and noncompetitive with oxaloacetate; with A. anitratum, NADH is noncompetitive with both substrates. Acinetobacter anitratum citrate synthase shows hyperbolic saturation with acetyl-CoA (n = 1.8). The finding of Weitzman and Jones (Nature (London) 219, 270 (1968) that NADH inhibition of the enzyme from Acinetobacter spp. is reversible by AMP, while that from E. coli is not, is explained by the much greater affinity of the E. coli enzyme for NADH. Unlike E. coli citrate synthase, the A. anitratum enzyme does not react with the sulfhydryl reagent 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) in the absence of denaturation. With a second sulfhydryl reagent, 4,4'-dithiodipyridine (4,4'-PDS), the A. anitratum enzyme reacts with 1 equiv. of subunit; this modification induces a partial activity loss (attributable to a arise in the Km for acetyl-CoA) and an increase in the sensitivity to NADH. With the E. coli enzyme, 4,4'-PDS causes complete inactivation. Acinetobacter anitratum citrate synthase is much more resistant to urea denaturation than the E. coli enzyme is; the resistance of both enzymes to urea is greatly improved in the presence of 1 M KCl. It is suggested that the amino acid sequences of the subunits of the citrate synthases of these two bacteria are about 90% homologous, and that the 10% differences are in key residues, perhaps largely in the subunit contact regions, which account for the differences in allosteric properties.

Acinetobacter↗
PubMed1994

Antibiotic-resistant Acinetobacter meningitis in neurosurgical patients.

Acinetobacter anitratus has emerged as one of the common pathogens responsible for postneurosurgical meningitis at the authors' institution. Seven patients with Acinetobacter meningitis were identified during the 4-year period of this study, five of whom acquired organisms susceptible only to imipenem and amikacin. Acinetobacter bacteremia occurred concomitantly in five patients. Despite late institution of therapy as a result either of organism misidentification on Gram stain or of unexpected acquisition of a highly resistant organism, the patients' outcome was favorable after the initiation of appropriate antibiotic therapy. Imipenem and amikacin, with or without intrathecal aminoglycosides, were effective in patients with resistant strains of Acinetobacter.

Acinetobacter Infections↗
PubMed1999

Acinetobacter meningitis: four nosocomial cases.

We report the clinical features and therapeutic outcomes of four patients with multiantibiotic-resistant Acinetobacter meningitis. There were three males and one female, aged from 17 to 49 years. Three of them had suffered from head injuries with skull fractures, and the other suffered from an intracerebral hemorrhage and underwent a craniotomy. All four patients acquired nosocomial Acinetobacter meningitis, and multiantibiotic resistance developed. After treatment with imipenem/cilastatin, three of the four patients survived; one died of multiorgan failure. Because the clinical manifestations of Acinetobacter meningitis are similar to those of other gram-negative bacillary meningitis, the diagnosis can only be confirmed by bacterial culture. Resistance to multiple antibiotics, including third-generation cephalosporins, is frequently seen in patients with nosocomial Acinetobacter meningitis, and imipenem/cilastatin seems to be the antibiotic of choice for this potentially fatal central nervous system infection.

Acinetobacter Infections↗
PubMedDate not supplied

[Isolation and study of Acinetobacter sp. mutant strains defective in production of exopolysaccharides].

Nitrosoguanidine-induced mutants of Acinetobacter sp. defective in exopolysaccharide biosynthesis did not differ from the parent strain in distinguishing physiological and biochemical properties, such as requirements for growth factors, utilization of mono- and disaccharides, and resistance to antibiotics. The genetic relation of parent and mutant strains was shown by 16S rRNA PCR analysis. The comparative study of parent and mutant strains with respect to resistance to unfavorable environmental factors confirmed our hypothesis that Acinetobacter sp. exopolysaccharides perform protective functions. Hybridization experiments revealed the conjugal transfer of plasmid R68.45 from Pseudomonas putida BS228 (R68.45) to mutant but not to the parent Acinetobacter sp. strains. The role of the Acinetobacter sp. exopolysaccharides in providing the genetic stability of this bacterium is discussed.

Acinetobacter↗
PubMedDate not supplied

[Exopolysaccharide production and peculiarities of C6-metabolism in Acinetobacter sp. grown on carbohydrate substrates].

An Acinetobacter sp. strain grown on carbohydrate substrates (mono- and disaccharides, molasses, starch) was shown to synthesize exopolysaccharides (EPS). Glucose catabolism proved to proceed via the Embden-Meyerhof-Parnas and Entner-Doudoroff pathways. Pyruvate entered the tricarboxylic acid cycle due to pyruvate dehydrogenase activity. Pyruvate carboxylation by pyruvate carboxylase was the anaplerotic reaction providing for the synthesis of intermediates for the constructive metabolism of Acinetobacter sp. grown on C6-substrates. The C6-metabolism in Acinetobacter sp. was limited by coenzyme A. Irrespective of the carbohydrate growth substrate (glucose, ethanol), the activities of the key enzymes of both C2- and C6-metabolism was high, except for the isocitrate lyase activity in glucose-grown bacteria. Isocitrate lyase activity was induced by C2-compounds (ethanol or acetate). After their addition to glucose-containing medium, both substrates were utilized simultaneously, and an increase was observed in the EPS synthesis, as well as in the EPS yield relative to biomass. The mechanisms responsible for enhancing the EPS synthesis in Acinetobacter sp. grown on a mixture of C2- and C6-substrates are discussed.

Acetates↗
PubMed2003

[Assay of Acinetobacter SPP drug-resistance by Kirby-Bauer and Etest method].

OBJECTIVE: To study the drug-resistance of Acinetobacter spp and observe whether antibiotic-beta- lactamase inhibitor complexing agent enhances the sensitivity of the drug-resistant bacteria to the antibiotics. METHODS: Susceptibility tests to the antibiotics were performed for 60 isolated strains of Acinetobacter spp with Kirby-Bauer (K-B) and Etest methods. RESULTS: The drug-resistance rate of the strains to cefoperazone, ampicillin, ticarcillin and piperacillin exceeded 55.0%, and antibiotic-beta-lactamase inhibitor complexing agents evinced better antibacterial activity than antibiotics used alone (P < 0.001). The 2 antibiotic complexes incorporating sulbacta had more potent antibacterial activity than the complexes incorporating clavulanate (2 agents) and tazobactam (1 agent), with the mean ranks of 7.38, 6.43, 5.57, 5.47 and 5.50 respectively. Cefoperazone combined with sulbacta produced a reduction in MIC(90) and MIC(50) that were only 4.69% and 0.59% of the MIC(50) of cefoperazone, and in addition, sulbacta caused cefoperazone- and ampicillin-resistant rates to reduce from both 75.0% to 5.0% and 24.0%, respectively. CONCLUSION: Acinetobacter spp is resistant to a wide spectrum of commonly-used antibiotics, but cefoperazone in combination with sulbacta can obviously enhance antibacterial potency, suggesting the primary role of this regimen in fighting Acinetobacter spp infections in hospital.

Acinetobacter↗
PubMed2005

Characterization of Acinetobacter from clinical isolates at Gandhi memorial and associated hospitals, Lucknow.

The study was conducted in 4140 clinical samples sent to Microbiology department from different department of G.M. and associated hospitals. The samples included 2270 urine, 960 pus, 300 blood, 210 sputum, 180 CSF, 20 intercostal drainage tubes and 150 other swabs like vaginal and urethral, conjunctival smear 30, 10 ascitic fluids and 10 gastric aspirates. Apart from this, 30 specimens were collected from hospitals environment, like linen and trolley. From clinical samples, 43 acinetobacter strains (1.04%) were isolated. 17 strains (0.41%), were from pus, 12 (0.28%), from respiratory tract, 1, was (0.02%) from intercostal drainage secretions, urine 9 (0.22%), blood 1 (0.2%) and CSF 3 (.72%). From environmental samples, 7 strains (23.33%) were isolated. All the isolated strains were identified by routine biochemical tests. They were preserved in 1 % agar media for characterization. Characterization was done on the basis of growth at 37 degrees c, 41 degrees c and 44 degrees c, hemolysis, gelatin hydrolysis, acid from glucose, utilization of citrate, L-phenyl alanine, malonate, B-alanine, L-arginine, L-ornithine and L-aspartate. Among species identified Acinetobacter baumannii was 30 (69.67%), from clinical specimens and 5 (71.42%) from environment, Acinetobacter lwoffi was 10 (23.25%) from clinical specimen and 2 from environmental specimen, Acinetobacter hemolyticus was 3 (6.97%) and none from the environment. All the strains were resistant to penicillin. The sensitivity pattern showed gentamycin 64% sensitive, cotrimaxazole 42% cefotoxin 32% ciprofloxacine 26% and tetracycline 16%.

Acinetobacter↗
PubMed2006

Characterization of beta-ketoadipate pathway from multi-drug resistance bacterium, Acinetobacter baumannii DU202 by proteomic approach.

In this study, the biodegradative activities of monocyclic aromatic compounds were determined from the multi-drug resistant (MDR) Acinetobacter baumannii, which were studied in the form of clinical isolates from a hospital in Korea. These bacteria were capable of biodegrading monocyclic aromatic compounds, such as benzoate and p-hydroxybenzoate. In order to determine which pathways are available for biodegradation in these stains, we conducted proteome analyses of benzoate and p-hydroxybenzoate-cultured A. baumannii DU202, using 2-DE/MS analysis. As genome DB of A. baumannii was not yet available, MS/MS analysis or de novo sequencing methods were employed in the identification of induced proteins. Benzoate branch enzymes [catechol 1,2-dioxygenase (CatA) and benzoate dioxygenase alpha subunit (BenA)] of the beta-ketoadipate pathway were identified under benzoate culture condition and p-hydroxybenzoate branch enzymes [protocatechuate 3,4-dioxygenase alpha subunit (PcaG) and 3-carboxy-cis,cis-muconate cycloisomerase (PcaB)] of the beta-ketoadipate pathway were identified under p-hydroxybenzoate culture condition, respectively, thereby suggesting that strain DU202 utilized the beta-ketoadipate pathway for the biodegradation of monocyclic aromatic compounds. The sequence analysis of two purified dioxygenases (CatA and PcaGH) indicated that CatA is closely associated with the CatA of Acinetobacter radiresistance, but PcaGH is only moderately associated with the PcaGH of Acinetobacter sp. ADP1. Interestingly, the fused form of PcaD and PcaC, carboxymuconolactone decarboxylase (PcaCD), was detected on benzoate-cultured A. baumannii DU202. These results indicate that A. baumannii DU202 exploits a different beta-ketoadipate pathway from other Acinetobacter species.

Acinetobacter baumannii↗