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PubMedDate not supplied

Immunization against turkey coryza by colonization with mutants of Alcaligenes faecalis.

Temperature-sensitive mutants of Alcaligenes faecalis that exhibited reduced growth at 42 C but grew well at 30 C were induced by N-methyl-N'-nitro-N-nitrosoguanidine. Four of the 5 mutants that were studied readily colonized the nasal mucosa of turkeys when given intranasally or in drinking water. Several mutants caused no signs of coryza or depression and produced minimal colonization of the trachea. Colonization of the nasal mucosa lasted 3 to 4 weeks and induced moderate levels of serum antibodies. When challenged with virulent isolates of A. faecalis 4 to 6 weeks after having been exposed to the mutants, unstressed turkeys were protected; turkeys subjected to water deprivation exhibited some colonization with the virulent strain and showed slight signs of coryza.

Alcaligenes↗
PubMed1994

Primary sequence and evidence for a physiological function of the flavohemoprotein of Alcaligenes eutrophus.

The flavohemoprotein (FHP) encoding gene of the strictly respiratory Gram-negative bacterium Alcaligenes eutrophus was isolated from a megaplasmid library by using FHP-specific antibodies and oligonucleotide probes based on the amino-terminal polypeptide sequence of FHP, determined previously (Zhu, H., and Riggs, A. F. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 5015-5019). The fhp gene codes for a monomeric polypeptide of 403 amino acids (M(r) 44,796) whose structure is highly homologous to the proteins of the two-domain flavohemoglobin family, comprising the hemoproteins from Escherichia coli and Saccharomyces cerevisiae. FHP consists of an amino-terminal-located O2-binding hemoglobin domain and a carboxyl-terminal-located redoxactive domain with potential binding sites for NAD(P)H and FAD. Two potential binding motifs for NARL and FNR upstream of fhp suggest a role of FHP in the anaerobic metabolism of A. eutrophus. Isogenic Fhp-negative mutants showed no significant delay in aerobic or anaerobic growth. Compared with the wild type, however, the mutant did not accumulate nitrous oxide during denitrification with nitrite as electron acceptor. This property was restored by complementation. The result suggests that FHP interacts directly or indirectly with the gas metabolism during denitrification in A. eutrophus.

Alcaligenes↗
PubMed1996

[Introduction of mutator phage D3112 of Pseudomonas aeruginosa into Alcaligenes eutrophus var. metallotollerans (Strain CH34)].

It is demonstrated that the intact genome of a D3112 tranposable phage (TP) of Pseudomonas aeruginosa, integrated into a recombinant plasmid RP4 :: D3112, can be transferred by means of conjugation from P. putida PpG1 (RP4npt :: D3112) donor cells into Alcaligenes eutrophus var. metallotollerans cells. P. aeruginosa strains are unacceptable as donors because they have a bactericidal effect on A. eutrophus. RP4npt :: D3112 plasmid is stably inherited by A. eutrophus with D3112 being expressed and successfully reproduced. However, TP loses the induction ability after UV irradiation or mitomycin C treatment. It is suggested that D3112 TP and its miniderivatives could be used in manipulations with A. eutrophus var. metallotolerans.

Alcaligenes↗
PubMed1996

Alcaligenes xylosoxidans neonatal meningitis: a case report.

Neonatal meningitis caused by Alcaligenes xylosoxidans is associated with a high mortality rate. The causative microorganism is resistant to most antimicrobials. Generally, once the organism has been isolated from the cerebrospinal fluid of the infected neonate, initial therapy with a third-generation cephalosporin and trimethoprim-sulfamethoxazole is recommended before determining its susceptibility to antimicrobials. There present this is the first of neonatal meningitis with transient diabetes insipidus cause by A. xylosoxidans. The patient was treated with dDAVP for seven days and a combination of imipenem plus trimethoprim-sulfamethoxazole for 28 days. The patient was discharged in a stable condition and the end of that time, but with sequelae of hydrocephalus and hearing impairment.

Alcaligenes↗
PubMedDate not supplied

[Bacteremia caused by Alcaligenes (Achromobacter) xylosoxidans. Description of 3 cases and review of the literature].

BACKGROUND: Alcaligenes (Achromobacter) xylosoxidans occasionally cause infections, mainly in immunocompromised hosts. METHODS: Three cases of bacteremia due to A. xylosoxidans observed at the Fundación Jiménez Díaz between 1985-1994 were described. Moreover, 38 single cases of bacteremia due to A. xylosoxidans and 21 episodes associated with outbreak were reviewed by using computerized bibliography data base MEDLINE (1970-december 1994). RESULTS: From 41 patients with bacteremia (including our 3 cases) reviewed, 27 were immunosuppressed hosts (twenty had neoplasia disease). The most common clinical presentation was primary bacteremia (11 cases, 27%) and pneumonia (10, 24%), followed by catheter-associated bacteremia (8, 20%), meningitis (4), bacteremia from abdominal cavity (4), endocarditis (3) and pyelonephritis (1). The mortality rate was higher (39%), specially in patients whom were a intensive care unit acquisition (87%), and illness with endocarditis (100%). No patient with catheter-related bacteremia died. All of 21 outbreak episodes of bacteremia had a autolimited form and low mortality (4.8%). CONCLUSION: A. xylosoxidans is a microorganism with demonstrated capacity of cause bacteremia, mainly in immunocompromised hosts, with high mortality rates. Sometimes, it causes outbreaks of bacteremia with low mortality.

Adolescent↗
PubMed1996

[Bacterial endotoxins produced by Alcaligenes faecalis and Erwinia herbicola as potential occupational hazards for agricultural workers].

Laboratory animals (guinea pigs and rabbits) were exposed to the inhalation of aerosolized endotoxins derived from the cell mass of Alcaligenes faecalis and Erwinia herbicola, the Gram-negative bacteria commonly occurring in organic dusts. Single 1 hour-lasting exposure caused the significant increase in the number of free lung cell, mostly lymphocytes, compared to the control group exposed to saline (P < 0.001). Prolonged exposure to tested endotoxins (Fifteen 1 hour-lasting exposures every second day) caused both specific and non specific immunological changes: enhanced inhibition of leukocyte migration production of precipitins, and activation of alveolar macrophages, wes assessed by greater antibacterial activity and increased interleukin I (IL-I) production. The results indicate that the endotoxins of examined bacteria represent a potential risk of inflammatory lung reaction and respiratory disease for agricultural workers inhaling organic dusts contaminated with these organisms.

Administration, Inhalation↗
PubMed1997

Studies on multiple forms of maltotetraose-forming amylase from Alcaligenes sp.

Zymograms of the cultural supernatant of Alcaligenes sp. showed three bands, the major one being G4A-1 and the minor two, G4A-2 and G4A-3. Based on the electrophoretic homogeneity of the purified three bands and the enzymatic activities identified by a thin layer chromatography of the soluble starch hydrolysates, all the three bands were confirmed to be maltotetraose-forming amylase but in multiple forms. Neither glycosidase nor protease activities could be detected in the culture (only very weak protease activities were observed at 48 hours after cultivation), which indicate that the two enzymes were not involved in the amylase multiple-form formation. Only the relative amount of the two minor bands (but not the multiple-form pattern) was changed when the initial pH of the medium varied from 6.5-8.5. An addition of 0.3% glucose raised the yield of G4A-2 and G4A-3.

Alcaligenes↗
PubMed1997

Cloning and characterization of the regulatory genes phlR1 and phlR2 involved in phenol metabolism from Alcaligenes eutrophus JMP134.

One mutant (AEK201) of Alcaligenes eutrophus JMP134 deficient in phenol metabolism was isolated by transposon mutagenesis using pSUP2021, a suicide plasmid. The 14.5 kb EcoRI fragment containing Tn5 and flanking DNA was cloned from AEK201 and used to probe a gene bank of wild type by colony hybridization. All five positive cosmids isolated rendered AEK201 to grow on phenol. The data from subcloning revealed that a trans-acting factor encoded on the 2.3 kb SalI-HindIII fragment, which is common to all cosmids, allowed the mutant to restore three enzyme activities tested (phenol hydroxylase, catechol 1,2-dioxygenase, and catechol 2,3-dioxygenase). This fragment seems to act as a positive regulator on the entire phenol pathway. Another regulatory segment was subcloned from the 16.8 kb HindIII fragment on which phenol hydroxylase and catechol 2,3-dioxygenase activities were carried [Kim, Y., Ayoubi, P., and Harker, A. R. (1996) Appl. Environ. Microbiol. 62, 3227-3233]. The expression of phenol hydroxylase activity was entirely repressed in the presence of this segment in Pseudomonas aeruginosa PAO1c, but the enzyme activity was increased in A. eutrophus AEK301, suggesting that this trans-acting factor is both an activator and a repressor for phenol hydroxylase. Possible regulatory mechanisms for the phenol pathway in A. eutrophus JMP134 are discussed.

Alcaligenes↗
PubMed1976

[Specific polysaccharides of alkali-forming enterobacteria. II. Separation of a hydrolysate of B. faecalis alcaligenes specific polysaccharide on a column with cellulose].

Paper and gas-liquid chromatography was applied to the study of monosaccharide composition of specific polysaccharide from B. faecalis alcaligenes. Lipophilic sugar of unknown chemical nature was revealed in the composition of this polysaccharide. Conditions for separation of acid hydrolyzate of the specific polysaccharide of this culture in a column with cellulose powder for the purpose of preparative obtaining of the unknown sugar were elaborated.

Alcaligenes↗
PubMed1999

Control of acetic acid concentration by pH-stat continuous substrate feeding in heterotrophic culture phase of two-stage cultivation of Alcaligenes eutrophus for production of P(3HB) from CO2, H2, and O2 under non-explosive conditions.

A-two stage culture method of hydrogen-oxidizing bacterium, Alcaligenes eutrophus, is used to produce poly-D-3-hydroxybutyrate, P(3HB) from CO2, O2, and H2 without using a very high oxygen transfer rate while maintaining the O2 concentration in gas phase below 6.9 (v/v)% to prevent detonation of the gas mixture. The two-stage method consists of a heterotrophic culture using fructose as carbon source for exponential cell growth and an autotrophic culture for P(3HB) accumulation. We investigated the use of acetic acid as a cheaper carbon source than fructose for the heterotrophic culture in the two-stage method. However, the acetate concentration in the culture system must be maintained at 1.0 g. dm-3 since its inhibitory effect on the cell growth is very strong. Then, high cell density cultivation of A. eutrophus was investigated by pH-stat continuous feeding of acetic acid to control acetate concentration. As a result, acetate concentration was automatically maintained around 1.0 g. dm-3 by using a feed with a composition in CH3COOH/CH3COONH4/KH2PO4 molar ratio of 5:1:0.084. Cell concentration increased to 48.6 g. dm-3 after 21 h of cultivation. The cell mass grown in the fed-batch culture on acetic acid was useful for P(3HB) production from CO2 in the subsequent autotrophic culture stage. Copyright 1999 John Wiley & Sons, Inc.

Journal Article↗
PubMed1997

Electrophoretic analysis of cyanide depletion by Pseudomonas alcaligenes.

Bacterial-facilitated depletion of cyanide is under development for remediation of heap leach operations in the gold mining industry. Capillary electrophoresis was found to be a powerful tool for quantifying cyanide depletion. Changes in cyanide concentration in aqueous suspensions of Pseudomonas alcaligenes bacteria and cyanide at elevated pH were easily monitored by capillary electrophoresis. The resulting data can be used to study rates of cyanide depletion by this strain of bacteria. Concentrations of these bacteria at 10(5) cells/mL were found to reduce cyanide from 100 ppm to less than 8 ppm in four days. In addition, other ions of interest in cyanide metabolism, such as formate, can be simultaneously analyzed. Direct UV detection of cyanide at 192 nm further simplifies the analytical method for these ions.

Culture Media↗
PubMed1998

Biosorption of Heavy Metal Ions on Rhodobacter sphaeroides and Alcaligenes eutrophus H16

A fundamental study of the application of bacteria to the recovery of toxic heavy metals from aqueous environments was carried out. The biosorption characteristics of cadmium and lead ions were determined with purple nonsulfur bacteria, Rhodobacter sphaeroides and hydrogen bacteria, Alcaligenes eutrophus H16 that were inactivated by steam sterilization. A simplified version of the metal binding model proposed by Plette et al. was used for the description of metal binding data. The results showed that the biosorption of bivalent metal ions to whole cell bodies of the bacteria was due to monodentate binding to two different types of acidic sites: carboxilic and phosphatic-type sites. The number of metal binding sites of A. eutrophus was 2.4-fold larger than that of R. sphaeroides. Copyright 1998 Academic Press. Copyright 1998Academic Press

Journal Article↗
PubMed1998

Characterization of the Pac25I restriction-modification genes isolated from the endogenous pRA2 plasmid of Pseudomonas alcaligenes NCIB 9867.

Genes for the class II Pseudomonas alcaligenes NCIB 9867 restriction-modification (R-M) system, Pac25I, have been cloned from its 33-kb endogenous plasmid, pRA2. The Pac25I endonuclease and methylase genes were found to be aligned in a head-to-tail orientation with the methylase gene preceding and overlapping the endonuclease gene by 1 bp. The deduced amino acid sequence of the Pac25I methylase revealed significant similarity with the XcyI, XmaI, Cfr9I, and SmaI methylases. High sequence similarity was displayed between the Pac25I endonuclease and the XcyI, XmaI, and Cfr9I endonucleases which cleave between the external cytosines of the recognition sequence (i.e., 5'-C CCGGG-3') and are thus perfect isoschizomers. However, no sequence similarity was detected between the Pac25I endonuclease and the SmaI endonuclease which cleaves between the internal CpG of the recognition sequence (i.e., 5'-CCCGGG-3'). Both the Pac25I methylase and endonuclease were expressed in Escherichia coli. An open reading frame encoding a protein which shows significant similarity to invertases and resolvases was located immediately upstream of the Pac25I R-M operon. In addition, a transposon designated Tn5563 was located 1531 bp downstream of the R-M genes. The location on a self-transmissible plasmid as well as the close association with genes involved in DNA mobility suggests horizontal transfer as a possible mode of distribution of this family of R-M genes in various bacteria.

Amino Acid Sequence↗
PubMed1998

Duplication of hyp genes involved in maturation of [NiFe] hydrogenases in Alcaligenes eutrophus H16.

Alcaligenes eutrophus H16 harbors seven hyp genes (hypA, B, F, C, D, E, and X) as part of the hydrogenase gene cluster on megaplasmid pHG1. Here we demonstrate that three of the hyp genes (hypA, B, and F) are duplicated in A. eutrophus, which explains the lack of a phenotypic change in single-site mutants impaired in one of the two copies. Mutants with lesions in both copies showed clear alterations in hydrogenase activities. Deletions in hypF1 and hypF2 completely abolished activities of the soluble hydrogenase and of the membrane-bound hydrogenase, mutations in hypA1 and hypA2 totally blocked the membrane-bound hydrogenase activity, while residual soluble hydrogenase activity accounted for the extremely slow growth of the strain on H2. Both hydrogenase activities of mutants defective in hypB1 and hypB2 were partially restored by elevating the concentration of nickel chloride in the medium. Reduction of hydrogenase activities in the double mutants correlated with varying degrees of maturation deficiency based upon the amount of unprocessed nickel-free hydrogenase precursor. Despite a high identity between the two copies of hyp gene products, substantial structural differences were identified between the two copies of hypF genes. HypF1, although functionally active, is a truncated version of HypF2, whose structure resembles HypF proteins of other organisms. Interestingly, the N-terminus of HypF2, which is missing in the HypF1 counterpart, contains a putative acylphosphatase domain in addition to a potential metal binding site.

Bacterial Proteins↗
PubMed1998

hoxX (hypX) is a functional member of the Alcaligenes eutrophus hyp gene cluster.

The role of HoxX in hydrogenase biosynthesis of Alcaligenes eutrophus H16 was re-examined. The previously characterized hoxX deletion mutant HF344 and a newly constructed second hoxX mutant carrying a smaller in-frame deletion were studied. The second mutant was impaired in the activity of both the soluble and the membrane-bound hydrogenase. The two hydrogenase activities were reduced by approximately 50% due to delayed processing of the active-site-containing large subunits, while hydrogenase gene expression was not affected. We conclude that the mutation in mutant HF344 causes polarity resulting in the observed regulatory phenotype of this mutant. The data presented in this report point to an enhancing function of HoxX in the conversion of the soluble hydrogenase and of the membrane-bound hydrogenase large-subunit precursor. Thus, hoxX encodes a member of the Hyp proteins that are required for the formation of active hydrogenase and was accordingly renamed hypX.

Bacterial Proteins↗
PubMed2006

Immobilization of permeabilized whole cell penicillin G acylase from Alcaligenes faecalis using pore matrix crosslinked with glutaraldehyde.

The activity of penicillin G acylase from Alcaligenes faecalis increased 7.5-fold when cells were permeabilized with 0.3% (w/v) CTAB. The treated cells were entrapped by polyvinyl alcohol crosslinked with boric acid, and crosslinked with 2% (v/v) glutaraldehyde to increase the stability. The conversion yield of penicillin G to 6-aminopenicillanic acid was 75% by immobilized system in batch reaction. No activity was lost after 15 cycles and about 65% enzyme activity was retained at the end of the 31th cycle.

Cell Culture Techniques↗
PubMed1998

Characterization of the active site of a hydrogen sensor from Alcaligenes eutrophus.

A third hydrogenase was recently identified in the proteobacterium Alcaligenes eutrophus as a constituent of a novel H2-sensing multicomponent regulatory system. This regulatory hydrogenase (RH) has been overexpressed in cells deficient in both the NAD+-reducing [NiFe]-hydrogenase and the membrane-bound [NiFe]-hydrogenase. EPR, FTIR and activity studies of membrane-free extracts revealed that the RH has an active site much like that of standard [NiFe]-hydrogenases, i.e. a Ni-Fe site with two CN- groups and one CO molecule. Its catalytic power is low, but the RH is always active, insensitive to oxygen, and occurs in only two redox states.

Binding Sites↗