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PubMed1977

Rifampicin-resistant mutant supporting bacteriophage growth on stationary phase Achromobacter cells.

A rifampicin-resistant Achromobacter mutant with an altered RNA polymerase was isolated. The mutant supports phage alpha3a growth in both log and stationary phase cells. Phage growth on stationary phase cells is sensitive to aeration and growth only occurs at oxygen concentrations of less than 5-2 p.p.m. The rifampicin-resistant mutant is similar to the spontaneous mutant strain 14 reported by Woods (1976) in that both mutants support stationary-phase phage growth under micro-aerophilic conditions. The isolation of the rifampicin-resistant mutant with an altered RNA polymerase suggests that the phenomenon of stationary phase phage growth could be due to a change in the template specificity of the Achromobacter RNA polymerase. Plaque morphology mutants which grow on log and/or stationary phase cells of the Achromobacter wild type, strain 14 and rifampicin-resistant strains are also described.

Alcaligenes↗

PubMed1968

Morphological and biochemical differentiation of Achromobacter and Moraxella (DeBord's tribe Mimeae).

To determine the most useful laboratory tests for the differentiation of Achromobacter anitratus, Achromobacter lwoffii, and Moraxella duplex (DeBord's tribe Mimeae), 157 strains of these bacteria, isolated from clinical specimens, were examined for their morphological and biochemical characteristics. There were several differences between these nonfermentative, gram-negative diplococci: Moraxella was nonglucolytic in either infusion base or synthetic base, oxidase-positive, and sensitive to penicillin, whereas Achromobacter produced variable carbohydrate activity, and was oxidase-negative and resistant to penicillin. A. anitratus was distinguished from A. lwoffii in that the former utilized infusion media containing either glucose or 10% lactose, whereas the latter did not. Both species utilized the same carbohydrates in a chemically defined medium, although the latter acted more sluggishly.

Acinetobacter↗

PubMed1989

Cloning of a carbofuran hydrolase gene from Achromobacter sp. strain WM111 and its expression in gram-negative bacteria.

A 14-kilobase-pair (kbp) EcoRI DNA fragment that encodes an enzyme capable of rapid hydrolysis of N-methylcarbamate insecticides (carbofuran hydrolase) was cloned from carbofuran-degrading Achromobacter sp. strain WM111. When used to probe Southern blots containing plasmid and total DNAs from WM111, this 14-kbp fragment hybridized strongly to a 14-kbp EcoRI fragment from the greater than 100-kbp plasmid harbored by this strain but weakly to EcoRI-digested total DNA from Achromobacter sp. strain WM111, indicating that the gene for N-methylcarbamate degradation (mcd) is plasmid encoded. Further subcloning localized the mcd gene on a 3-kbp ScaI-ClaI fragment. There was little or no expression of this gene in the alternative gram-negative hosts Pseudomonas putida, Alcaligenes eutrophus, Acinetobacter calcoaceticus, and Achromobacter pestifer. Western blotting (immunoblotting) of the protein products produced by low-level expression in P. putida confirmed that this 3-kbp fragment encodes the two 70+-kilodalton protein products seen in sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified carbofuran hydrolase.

Alcaligenes↗

PubMed1965

Cyanide Resistance in Achromobacter II. Mechanism of Cyanide Resistance.

Oka, Tetuo (University of Tokyo, Tokyo, Japan), and Kei Arima. Cyanide resistance in Achromobacter. II. Mechanism of cyanide resistance. J. Bacteriol. 90:744-747. 1965.-Photochemical data showed that the only oxidase found in the cyanide-sensitive cells of Achromobacter was cytochrome o, and that cyanide-resistant cells contained at least two oxidases. The oxidase responsible for cyanide resistance was a pigment the CO compound of which had its absorption band at a wavelength longer than 580 mmu. In addition, kinetic data suggested that there were two oxidases having different affinities for cyanide. From the data presented, resistance to cyanide in Achromobacter strain D was attributed to the induced formation of cytochrome a(2), which has a very low affinity for cyanide. Several characteristics of cytochrome a(2) as a cytochrome oxidase are summarized.

Journal Article↗

PubMedDate not supplied

[Effect of nitrogen sources on growth and cholesterol decomposing activity of Mycobacterium rubrum and Achromobacter canadicans].

The effect of 12 sources of nitrogen on growth and cholesterine-decomposing activity was studied with Mycobacterium rubrum and Achromobacter candicans. The yield of biomass and the rate of cholesterine decomposition depended on the source of nitrogen and its concentration in the medium. The highest specific activity of the enzyme decomposing cholesterine was found during growth of the cultures on media containing reduced forms of nitrogen. The activity of the enzyme of Mycobacterium rubrum was by 25% higher than that of Achromobacter candicans. The optimum conditions for the production of the enzyme by Mycobacterium rubrum were on media containing 1.0 g of asparagine or 5.0 g of ammonium nitrate per one litre, and for the enzyme production by Achromobacter candicans, on media containing 5.0 g of ammonium phosphate per one litre.

Alcaligenes↗

PubMed2001

[Achromobacter xylosoxidans bacteremia in a patient with community-acquired pneumonia].

Achromobacter xylosoxidans is a rare cause of bacteremia, and little information on treatment is available. The majority of patients who have developed Achromobacter bacteremia have presented predisposing causes to the infection. A case of community-acquired pneumonia and bacteremia due to A. xylosoxidans in a previously healthy patient is reported. Achromobacter is usually resistant to ampicillin, cephalosporins (1st, 2nd, and 3rd generation), aminoglycosides, and fluoroquinolones. Piperacillin, piperacillin-tazobactam, and trimethoprim-sulfamethoxazole inhibit most isolates.

Aged↗

PubMed1994

Identification of three catalytic triad constituents and Asp-225 essential for function of lysine-specific serine protease, Achromobacter protease I.

Achromobacter protease I is a lysine-specific serine protease that Achromobacter lyticus M497-1 extracellularly secretes. The structural aspects necessary for the protease to function were investigated by means of site-directed mutagenesis to identify the constituents of the catalytic triad and the amino acid residue responsible for lysine specificity. The precursor molecules, which were produced by substitution of His-57, Asp-113, or Ser-194 for alanine, could not be converted to the mature form. In contrast, a precursor of a mutant in which either His-56 or Ser-193 is converted to alanine was perfectly processed autocatalytically and attained full protease activity. Substitution of Glu-190, one of the two candidates for determining lysine specificity, to glutamine, aspartic acid, or leucine had no or little effect on both proteolytic activity and substrate specificity. However, the kinetic parameters were subtly different from one another, depending on the nature of substituents in these mutants. The substitution of the other candidate, Asp-225, for asparagine or leucine resulted in the failure of maturation to the active forms. However, the precursor of the D225E mutant slowly matured and was essentially inactive. The observed reduction of protease activity is largely due to a decrease in the affinity of lysine to the protease. These results suggest that His-57, Asp-113, and Ser-194 are the three constituents of the catalytic triad in Achromobacter protease I and that Asp-225 plays a critical role in restricted substrate specificity as a lysyl endopeptidase.

Alcaligenes↗

PubMed1963

CORRELATION OF SPECIATION WITH LYTIC RESPONSES OF THE ACHROMOBACTER.

Surdy, Theodore E. (Purdue University, Lafayette, Ind.) and S. E. Hartsell. Correlation of speciation with lytic responses of the Achromobacter. J. Bacteriol. 85:1011-1016. 1963.-Lysozymic lysis of six species of Achromobacter was investigated. Three of the six species were lysed with 33, 50, or 100 mug/ml of lysozyme; if higher concentrations of lysozyme were used, precipitation of cells occurred. "Insensitive" cells could be sensitized by the addition of potassium hydroxide, n-butanol, steapsin, or urea, as demonstrated by the subsequent addition of lysozyme. Not all species were sensitive to these agents in the same degree; hence, a spectrum was obtained after the use of the pretreating agents and lysozyme. Optimal clearing of suspensions was observed when cells were suspended in pH 6.6 physiological saline or 0.15 m phosphate buffer and incubated at 45 C. Heat treatment (75 C for 10 min) or freezing (-32 C) and thawing (room temp, 25 C) for one cycle did not increase the sensitivity of the cells to lysozyme. Injury to the cells was evident by the increased amount of lysis noted after pretreatment with potassium hydroxide. When cells were frozen and thawed for three cycles, four of the six species were sensitive to the action of lysozyme. Isolated cell walls elicited a similar lytic pattern to that of whole cells. Individuality of the lytic response of the species (from most sensitive to least sensitive-A. aquamarinus, A. butyri, A. viscosus, A. parvulus, A. guttatus, A. hartlebii) produced a separation scheme. Exhaustive tests proved it to be stable and reliable for these species. The organisms were identified, with the use of the separation scheme, by a person initially unfamiliar with the scheme or the culture.

Achromobacter↗

PubMed1965

PYRUVATE METABOLISM, CARBON DIOXIDE ASSIMILATION, AND NITROGEN FIXATION BY AN ACHROMOBACTER SPECIES.

Hamilton, I. R. (University of Wisconsin, Madison), R. H. Burris, P. W. Wilson, and C. H. Wang. Pyruvate metabolism and carbon dioxide assimilation by an Achromobacter species. J. Bacteriol. 89:647-653. 1965.-Carbon dioxide fixation by washed whole cells of Achromobacter N4-B has been observed during anaerobic pyruvate metabolism with both nitrogen- and NH(4) (+)-grown cells. Labeled sodium bicarbonate-C(14) was assimilated into cells by a mechanism requiring pyruvate under conditions of nitrogen fixation, nitrogenase induction, and assimilation of NH(4) (+). Of the assimilated radioactivity, 89% appeared in six amino acids and two ninhydrin-positive unknown compounds, with the distribution of the label essentially independent of the nitrogen nutritional state of the organism. Aspartic and glutamic acids were the most highly labeled, with lesser amounts in glycine, alanine, ornithine, arginine, and the unknowns. All of the radioactivity extracted from these cells by ethanol-boiling water appeared in a protein fraction precipitated by 20% trichloroacetic acid. Radiorespirometric experiments with individually labeled pyruvate substrates demonstrated the preferential decarboxylation of the C-1 of pyruvate by this organism in a flowing helium gas phase. This decarboxylation was almost completely inhibited by using flowing nitrogen in place of helium; the addition of 0.5% CO(2) to the flowing nitrogen prevented inhibition and allowed 70% of the expected CO(2) evolution. These results, coupled with those from growth experiments, indicate a carbon dioxide requirement for anaerobic growth and pyruvate metabolism, which appears to be coupled to the formation of protein precursors.

Achromobacter↗

PubMed2005

A novel bacterium Achromobacter xylosoxidans as a cause of liver abscess: three case reports.

Achromobacter xylosoxidans is a microorganism that may cause opportunistic infections. We detected A. xylosoxidans in three of 46 patients with liver abscess. The clinicopathologic findings of the three patients were uniform with respect to a prior history of cholecystectomy, multi-lobulated 'coral-like' abscess under CT and epithelioid granulomas in the periphery of the abscess. Achromobacter xylosoxidans is an unrecognized cause of liver abscess in humans.

Achromobacter denitrificans↗

PubMed2003

Kerstersia gyiorum gen. nov., sp. nov., a novel Alcaligenes faecalis-like organism isolated from human clinical samples, and reclassification of Alcaligenes denitrificans Rüger and Tan 1983 as Achromobacter denitrificans comb. nov.

A polyphasic taxonomic study was performed on nine isolates recovered from various human clinical samples. Phenotypically, these isolates resembled Alcaligenes faecalis. Whole-cell protein analysis distinguished two different species, and this was confirmed by DNA-DNA hybridizations. Cellular fatty acid analysis and 16S rDNA sequence analysis indicated that these isolates were related to the genera Alcaligenes, Bordetella, Achromobacter and Pigmentiphaga and belonged to the family Alcaligenaceae. On the basis of the results of this study, the organisms were classified in a novel genus, Kerstersia gen. nov. This genus comprises one species, Kerstersia gyiorum sp. nov. (type strain LMG 5906(T)=API 184-2-84(T)=CCUG 47000(T)), and several unnamed isolates. The DNA G+C content of members of the genus Kerstersia is between 61.5 and 62.9 mol%. On the basis of previously published DNA-DNA hybridization results and data from chemotaxonomic studies, it is proposed that Alcaligenes denitrificans Rüger and Tan 1983 be reclassified as Achromobacter denitrificans comb. nov.

Achromobacter↗

PubMed2006

Pannonibacter phragmitetus, described from a Hungarian soda lake in 2003, had been recognized several decades earlier from human blood cultures as Achromobacter groups B and E.

We performed a polyphasic taxonomic study on isolates previously tentatively classified as Achromobacter groups B and E in comparison with the type strain of Pannonibacter phragmitetus, LMG 22736(T)=NCTC 13350(T). Comparative 16S rRNA gene sequence analysis suggested that strains of Achromobacter groups B and E belong to P. phragmitetus (similarity levels were higher than 99 %). DNA-DNA hybridization experiments and other genotypic and phenotypic analyses confirmed that the three taxa represent a single species. Whilst P. phragmitetus was described in 2003 from a Hungarian soda lake, it had been observed in human blood cultures in the UK since 1975. We present here the characteristics of the organism to facilitate its recognition in human clinical specimens and hence to determine its clinical significance.

Achromobacter↗

PubMed2006

Fluorescence in situ hybridization for rapid identification of Achromobacter xylosoxidans and Alcaligenes faecalis recovered from cystic fibrosis patients.

Achromobacter xylosoxidans is frequently isolated from the respiratory secretions of cystic fibrosis (CF) patients, but identification with biochemical tests is unreliable. We describe fluorescence in situ hybridization assays for the rapid identification of Achromobacter xylosoxidans and Alcaligenes faecalis. Both assays showed high sensitivities and high specificities with a collection of 155 nonfermenters from CF patients.

Achromobacter denitrificans↗

PubMed2004

Pacemaker lead endocarditis caused by Achromobacter xylosoxidans.

We report the case of a 35-yr-old patient who presented with high fever and chills. He had undergone a patch closure of the ventricular septal defect 18 yr before. One year later, a VVI pacemaker was implanted via the right subclavian vein because of complete heart block. Nine years after that, a new VVI pacemaker with another right ventricular electrode was inserted controlaterally and the old pacing lead was abandoned. Trans-thoracic and trans-esophageal echocardiogram identified the pacemaker lead in the right ventricle (RV) attaching hyperechoic materials and also a fluttering round hyperechoic mass with a stalk in the RV outflow tract. Cultures in blood and pus from pacemaker lead grew Achromobacter xylosoxidans. A diagnosis of pacemaker lead endocarditis due to Achromobacter xylosoxidans was made. In this regards, the best treatment is an immediate removal of the entire pacing system and antimicrobial therapy.

Achromobacter denitrificans↗

PubMedDate not supplied

Infections due to Achromobacter xylosoxidans. Case report and review of the literature.

Achromobacter xylosoxidans is an uncommon nosocomial pathogen known to cause many serious infections. A 69-year-old woman with diabetes mellitus and chronic renal failure was admitted with pulmonary edema. The patient developed fever and pulmonary infiltrate with bilateral pleural effusions while she was on a respirator in the intensive care unit. Culture of sputum, pleural fluid and blood grew A. xylosoxidans. Bilateral chest tubes were inserted and the patient was treated for one month with piperacillin and trimethoprim-sulfamethoxazole. Gradual response, both clinically and radiologically, was noted after prolonged therapy. A review of the literature on infections due to A. xylosoxidans, the unique susceptibility pattern of the organism to various antibiotics and the use of combination therapy in Achromobacter infections are discussed.

Aged↗

PubMed2003

Achromobacter xylosoxidans bacteremia: a 10-year analysis of 54 cases.

Fifty-four cases of Achromobacter xylosoxidans bacteremia diagnosed over a 10-year period in patients from 2 months to 87 years of age were reviewed. Fifty-two episodes were nosocomial. The most frequent underlying condition was neoplasm (solid or hematological). The source of infection was a contaminated intravenous catheter in 35 patients (60%) and pneumonia in 6 patients. Eight (15%) patients died. The only risk factors significantly associated with mortality were age over 65 years and neutropenia. The results of in vitro susceptibility studies of the isolates showed that antibiotic therapy with antipseudomonal penicillins or carbapenems would be a reasonable choice. An epidemiological study conducted in the hemodialysis unit showed Achromobacter xylosoxidans in tap water and on the hands of two healthcare workers but not in the hemodialysis systems. Patients were probably contaminated when healthcare workers manipulated the intravenous catheters without wearing gloves.

Adolescent↗

PubMed2004

Persistent colonization of nine cystic fibrosis patients with an Achromobacter (Alcaligenes) xylosoxidans clone.

The present study was conducted to investigate the increasing incidence of Achromobacter (previously Alcaligenes) xylosoxidans isolates being recovered from sputum samples of cystic fibrosis patients at a cystic fibrosis department for adults in Athens, Greece. During the 1-year study period, a total of 34 isolates were detected persistently in 9 of 71 cystic fibrosis patients. The isolates exhibited resistance to multiple antimicrobial agents. Isolates that were recovered repeatedly from each patient exhibited identical macrorestriction profiles with pulsed-field gel electrophoresis, indicating that the same strain persisted in the lungs of these patients. Isolates from five of the patients were genetically related, suggesting a common-source outbreak of Achromobacter xylosoxidans colonization or infection.

Adolescent↗

PubMed1978

Subunit structure of Achromobacter collagenase.

The highly active form of collagenase (EC 3.4.24.3) from Achromobacter iophagus (specific activity 2 microkat/mg) has a molecular weight of 70,000 and the sedimentation coefficient s20,2 = 4.4 S. It is composed of two subunits of molecular weight 35,000 and s20,w of 2.9 S. The dissociation of the dimer under different conditions resulted in the complete and irreversible loss of enzymic activity. A unique N-terminal sequence Thr-Ala-Ala-Asp-Leu-Glu-Ala-Leu-Val- indicates that the two subunits are identical, at least in the N-terminal part of the polypeptide chain. Reduction and pyridylethylation of the subunit change neither molecular weight nor amino acid composition: therefore each subunit of molecular weight 35,000 consists of a single polypeptide chain. Another active and homogeneous form of Achromobacter collagenase (specific activity 1.64 microkat/mg) gives a value for the apparent molecular weight of 80,000 on sodium dodecyl sulphate-polyacrylamide electrophoresis. It is also a dimer in which each of the two subunits of molecular weight 35,000 binds non-covalently a peptide of molecular weight 5000. The dissociation of this form of collagenase is also accompanied by irreversible loss of enzymic activity. The amino acid composition of the subunits which were isolated from both 70,000 and 80,000 collagenases is the same. The role of dimer-monometer equilibrium in the biological function of collagenase is discussed.

Alcaligenes↗