501
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Abstract
Culture conditions, and other variables that modulate a cell's physiology, can bias a polymerase chain reaction (PCR) amplification against generating a representative population profile. Two Pseudomonas putida nahR alleles were constructed in pUC19 that differ solely in a 31-bp internal segment whose sequence has been inverted. After PCR amplification, the products could be distinguished on the basis of a change in a unique restriction site. When an Escherichia coli strain carrying one nahR allele is submitted to different growth conditions, the consequences of such variations on the relative PCR amplification of whole cells can be ascertained through coamplification with a strain carrying the other allele and subsequent restriction analysis. Cells in stationary phase displayed improved amplifiability while cells grown at 42 degrees C were equally amplifiable as compared to cells grown at 37 degrees C. However, sublethal levels of tetracycline or growth in minimal medium made the PCR target in these cells relatively less amplifiable. When cells are completely lysed and the plasmid DNA is purified beforehand, the coamplification bias is eliminated. These results suggest that mixed populations containing cells in different physiological states may not be representatively amplified by PCR unless a DNA extraction step is included.
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Affiliation(s)
- M C Silva
- Department of Food Science, Cornell University, Ithaca, NY 14853
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502
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O'Connor K, Buckley CM, Hartmans S, Dobson AD. Possible regulatory role for nonaromatic carbon sources in styrene degradation by Pseudomonas putida CA-3. Appl Environ Microbiol 1995; 61:544-8. [PMID: 7574594 PMCID: PMC167316 DOI: 10.1128/aem.61.2.544-548.1995] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Styrene metabolism in styrene-degrading Pseudomonas putida CA-3 cells has been shown to proceed via styrene oxide, phenylacetaldehyde, and phenylacetic acid. The initial step in styrene degradation by strain CA-3 is oxygen-dependent epoxidation of styrene to styrene oxide, which is subsequently isomerized to phenylacetaldehyde. Phenylacetaldehyde is then oxidized to phenylacetic acid. Styrene, styrene oxide, and phenylacetaldehyde induce the enzymes involved in the degradation of styrene to phenylacetic acid by P. putida CA-3. Phenylacetic acid-induced cells do not oxidize styrene or styrene oxide. Thus, styrene degradation by P. putida CA-3 can be subdivided further into an upper pathway which consists of styrene, styrene oxide, and phenylacetaldehyde and a lower pathway which begins with phenylacetic acid. Studies of the repression of styrene degradation by P. putida CA-3 show that glucose has no effect on the activity of styrene-degrading enzymes. However, both glutamate and citrate repress styrene degradation and phenylacetic acid degradation, showing a common control mechanism on upper pathway and lower pathway intermediates.
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Affiliation(s)
- K O'Connor
- Food Microbiology Department, University College, Cork, Ireland
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503
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Hope SJ, Slater JH. Cryptic dehalogenase and chloroamidase genes in Pseudomonas putida and the influence of environmental conditions on their expression. Arch Microbiol 1995; 163:57-64. [PMID: 7710321 DOI: 10.1007/bf00262204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Mutants of two strains of Pseudomonas putida expressed two cryptic chloroamidases (C-amidase and H-amidase) and one cryptic dehalogenase (DehII). The mutants were selected on either 2-chloropropionamide (2CPA) or 2-monochloropropionate (2MCPA), developing as papillae in parental colonies growing on a metabolisable support substrate. Mutants expressing C-amidase were selected if 2CPA was utilised as either a carbon or a nitrogen source. H-amidase mutants were selected only if 2CPA was used as a nitrogen source. Growth temperature and pH affected the frequency of papillae production, although different temperatures and pHs did not affect the overall growth characteristics of the parental colonies. Decreasing growth temperature increased the frequency of 2cpa+ papillae formation, but decreased the frequency of 2mcpa+ papillae formation. Low pH (6.0) prevented the formation of 2mcpa+ and 2cpa+ papillae. However, in the case of the 2cpa+ papillae, decreasing the growth temperature also allowed papillae formation at pH 6.0.
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Affiliation(s)
- S J Hope
- Molecular Ecology Research Unit, School of Pure and Applied Biology, University of Wales, Cardiff, UK
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504
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Abstract
Pseudomonas putida utilized methyl parathion as sole carbon and (or) phosphorus source. The bacterium elaborated the enzyme organophosphorus acid anhydrase, which hydrolyzed methyl parathion to p-nitrophenol. p-Nitrophenol was further degraded to hydroquinone and 1,2,4-benzenetriol. The final ring compound, 1,2,4-benzenetriol, was cleaved by benzenetriol oxygenase to maleyl acetate.
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Affiliation(s)
- N L Rani
- Department of Biochemistry, University of Nebraska, Lincoln 68583
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505
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Samygin VM, Stepin AA, Vladimtseva IV, Denisov II, Kukhtin VP. [The growth kinetics of Pseudomonas putida and its determining factors]. Zh Mikrobiol Epidemiol Immunobiol 1994:13-5. [PMID: 7879508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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506
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Cerdan P, Wasserfallen A, Rekik M, Timmis KN, Harayama S. Substrate specificity of catechol 2,3-dioxygenase encoded by TOL plasmid pWW0 of Pseudomonas putida and its relationship to cell growth. J Bacteriol 1994; 176:6074-81. [PMID: 7928969 PMCID: PMC196827 DOI: 10.1128/jb.176.19.6074-6081.1994] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Catechol 2,3-dioxygenase encoded by TOL plasmid pWW0 of Pseudomonas putida consists of four identical subunits, each containing one ferrous ion. The enzyme catalyzes ring cleavage of catechol, 3-methylcatechol, and 4-methylcatechol but shows only weak activity toward 4-ethylcatechol. Two mutants of catechol 2,3-dioxygenases (4ECR1 and 4ECR6) able to oxidize 4-ethylcatechol, one mutant (3MCS) which exhibits only weak activity toward 3-methylcatechol but retained the ability to cleave catechol and 4-methylcatechol, and one phenotypic revertant of 3MCS (3MCR) which had regained the ability to oxidize 3-methylcatechol were characterized by determining their Km and partition ratio (the ratio of productive catalysis to suicide catalysis). The amino acid substitutions in the four mutant enzymes were also identified by sequencing their structural genes. Wild-type catechol 2,3-dioxygenase was inactivated during the catalysis of 4-ethylcatechol and thus had a low partition ratio for this substrate, whereas the two mutant enzymes, 4ECR1 and 4ECR6, had higher partition ratios for it. Similarly, mutant enzyme 3MCS had a lower partition ratio for 3-methylcatechol than that of 3MCR. Molecular oxygen was required for the inactivation of the wild-type enzyme by 4-ethylcatechol and of 3MCS by 3-methylcatechol, and the inactivated enzymes could be reactivated by incubation with FeSO4 plus ascorbic acid. The enzyme inactivation is thus most likely mechanism based and occurred principally by oxidation and/or removal of the ferrous ion in the catalytic center. In general, partition ratios for catechols lower than 18,000 did not support bacterial growth. A possible meaning of the critical value of the partition ratio is discussed.
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Affiliation(s)
- P Cerdan
- Department of Medical Biochemistry, University Medical Center, Geneva, Switzerland
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507
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Kessler B, Marqués S, Köhler T, Ramos JL, Timmis KN, de Lorenzo V. Cross talk between catabolic pathways in Pseudomonas putida: XylS-dependent and -independent activation of the TOL meta operon requires the same cis-acting sequences within the Pm promoter. J Bacteriol 1994; 176:5578-82. [PMID: 8071244 PMCID: PMC196754 DOI: 10.1128/jb.176.17.5578-5582.1994] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The Pm promoter of the meta cleavage operon in the TOL (toluene degradation) plasmid pWW0 of Pseudomonas putida becomes activated by the plasmid-encoded XylS regulator in the presence of benzoate and certain substituted analogs such as 3-methylbenzoate. In the absence of XylS, Pm was still responsive to unsubstituted benzoate but with induction kinetics and a range of transcriptional activity which differed substantially from those for the XylS-mediated activation. XylS-independent induction by benzoate did not occur in a rpoN genetic background. Pm was also silent while cells were actively growing in rich medium. However, XylS-dependent transcription and XylS-independent transcription were initiated at the same nucleotide, as determined with primer extension mapping. Furthermore, a series of deletions and mutations at the Pm promoter sequence showed the same overall pattern of responsiveness to benzoate with and without XylS, thus providing genetic evidence that the same promoter structure is recognized and activated by at least two different regulators. One of them is XylS, while the other, provided by the host bacterium, could be related to the chromosome-encoded benzoate degradation pathway.
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Affiliation(s)
- B Kessler
- GBF-National Research Center for Biotechnology, Braunschweig, Germany
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508
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Abstract
Gas chromatographic and mass spectrometric analyses of derivatized culture medium extracts were used to identify the products of flavonoid metabolism by rhizobia. A number of Rhizobium species and biovars degraded their nod gene-inducing flavonoids by mechanisms which originated in a cleavage of the C-ring of the molecule and which yielded conserved A- and B-ring products among the metabolites. In contrast, Pseudomonas putida degraded quercetin via an initial fission in its A-ring, and Agrobacterium tumefaciens displayed a nonspecific mode of flavonoid degradation which yielded no conserved A- or B-ring products. When incubated with rhizobia, flavonoids with OH substitutions at the 5 and 7 positions yielded phloroglucinol as the conserved A-ring product, and those with a single OH substitution at the 7 position yielded resorcinol. A wider range of structures was found among the B-ring derivatives, including p-coumaric, p-hydroxybenzoic, protocatechuic, phenylacetic, and caffeic acids. The isoflavonoids genistein and daidzein were also degraded via C-ring fission by Rhizobium fredii and Rhizobium sp. strain NGR234, respectively. Partially characterized aromatic metabolites with potential nod gene-inducing activity were detected among the products of naringenin degradation by Rhizobium leguminosarum bv. viciae. The initial structural modification of nod gene-inducing flavonoids by rhizobia can generate chalcones, whose open C-ring system may have implications for the binding of inducers to the nodD gene product.
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Affiliation(s)
- J R Rao
- Department of Applied Plant Science, Queen's University of Belfast, Northern Ireland, United Kingdom
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509
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Banat IM, Marchant A, Nigam P, Gaston SJ, Kelly BA, Marchant R. Production, partial characterization, and potential diagnostic use of salicylate hydroxylase from Pseudomonas putida UUC-1. Enzyme Microb Technol 1994; 16:665-70. [PMID: 7765077 DOI: 10.1016/0141-0229(94)90087-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
An unusual strain of Pseudomonas putida UUC-1 capable of growth at high salicylate concentration (10 gl-1) was investigated with the aim of developing an assay and a biosensor system for determining salicylate in body fluids by utilizing the salicylate hydroxylase enzyme. Medium and growth condition optimization were carried out under chemostat conditions. The highest biomass yield was at 4.0 gl-1 salicylate, 25 degrees C, pH 6.5, and 0.2 h-1 dilution rate. Growth occurred at up to 0.45 h-1 dilution rate, producing 236 Ul-1 enzyme activity and an output of 424 U h-1. The activity and productivity were higher than any reported in the literature for this enzyme. It had a Km value of 2.07 +/- 0.32 microM and an M(r) of approximately 43,000. In addition, its specific activity in the crude extract (0.8-0.9 U mg-1 protein) was similar to the commercially available enzyme. No plasmid DNA was detected in this strain, and no salicylate-negative isolates were obtained when curing with mitomycin C. It is therefore proposed that our strain has a chromosomally located inducible salicylate hydroxylase gene that enables it to grow at high salicylate. This strain also offers a means of cheaply producing large quantities of the enzyme through standard fermentation techniques.
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Affiliation(s)
- I M Banat
- Department of Biological and Biomedical Sciences, University of Ulster, Coleraine, N. Ireland, UK
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510
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Olivera ER, Reglero A, Martínez-Blanco H, Fernández-Medarde A, Moreno MA, Luengo JM. Catabolism of aromatics in Pseudomonas putida U. Formal evidence that phenylacetic acid and 4-hydroxyphenylacetic acid are catabolized by two unrelated pathways. Eur J Biochem 1994; 221:375-81. [PMID: 8168524 DOI: 10.1111/j.1432-1033.1994.tb18749.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Phenylacetic acid (PhAcOH) and 4-hydroxyphenylacetic acid (4HOPhAcOH) are catabolized in Pseudomonas putida U through two different pathways. Mutation carried out with the transposon Tn5 has allowed the isolation of several mutants which, unlike the parental strain, are unable to grow in chemically defined medium containing either PhAcOH or 4HOPhAcOH as the sole carbon source. Analysis of these strains showed that the ten mutants unable to grow in PhAcOH medium grew well in the one containing 4HOPhAcOH, whereas four mutants handicapped in the degradation of 4HOPhAcOH were all able to utilize PhAcOH. These results show that the degradation of these two aromatic compounds in P. putida U is not carried out as formerly believed through a single linear and common pathway, but by two unrelated routes. Identification of the blocked point in the catabolic pathway and analysis of the intermediate accumulated, showed that the mutants unable to utilize 4HOPhAcOH corresponded to two different groups: those blocked in the gene encoding 4-hydroxyphenylacetic acid-3-hydroxylase; and those blocked in the gene encoding homoprotocatechuate-2,3-dioxygenase. Mutants unable to use PhAcOH as the sole carbon source have been also classified into two different groups: those which contain a functional PhAc-CoA ligase protein; and those lacking this enzyme activity.
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Affiliation(s)
- E R Olivera
- Departamento de Bioquímica y Biología Molecular, Facultad de Veterinaria, Universidad de León, Spain
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511
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Brinkmann U, Ramos JL, Reineke W. Loss of the TOL meta-cleavage pathway functions of Pseudomonas putida strain PaW1 (pWW0) during growth on toluene. J Basic Microbiol 1994; 34:303-9. [PMID: 7996396 DOI: 10.1002/jobm.3620340503] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A derivative of Pseudomonas putida strain PaW1 bearing the TOL plasmid pWW0 was isolated from a culture which has grown unlimited on toluene. In contrast to the parent strain PaW1, the derivative, strain CG220, is unable to grow with xylenes and toluates, while toluene and benzoate served as substrates. Strain CG220 had a remarkable growth advantage against the wild type when grown with toluene. Biochemical analysis showed that in strain CG220 toluene was metabolised through the TOL plasmid upper pathway to benzoate and the latter to amphibolic intermediates by the chromosomal encoded ortho-cleavage pathway. No activities of the TOL plasmid encoded toluate dioxygenase and catechol 2,3-dioxygenase were detectable in strain CG220. No reversion of strain CG220 to growth with xylenes or toluates was observed. Hybridisation experiments with TOL plasmid-derived gene probes and oligonucleotides revealed that genes xylY to xylG were absent, while xylX and xylK were still present.
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Affiliation(s)
- U Brinkmann
- Bergische Universität, Gesamthochschule Wuppertal, BRD
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512
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Tshisuaka B, Kappl R, Hüttermann J, Lingens F. Quinoline oxidoreductase from Pseudomonas putida 86: an improved purification procedure and electron paramagnetic resonance spectroscopy. Biochemistry 1993; 32:12928-34. [PMID: 8251516 DOI: 10.1021/bi00210a047] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Quinoline oxidoreductase, an iron-sulfur molybdenum flavoprotein containing flavin adenine dinucleotide and molybdopterin cytosine dinucleotide, was purified from Pseudomonas putida 86 to homogeneity. The various electron-transfer centers of the purified enzyme were examined by electron paramagnetic resonance spectroscopy. Quinoline deuterated at position 2 was prepared by deuterodecarboxylation of 2-quinolinecarboxylic acid. Quinoline added to the enzyme elicited the Mo(V) "rapid" type Q signal arising from the complex of enzyme and substrate, whereas in oxidized quinoline oxidoreductase a Mo(V) "resting" signal was observed. EPR spectroscopy at helium temperatures below 70 K revealed the existence of two types of iron-sulfur centers, Fe-S I and Fe-S II. An organic free radical appeared upon reduction with sodium dithionite. Inactivation of the enzyme by cyanide led to the inactive desulfo quinoline oxidoreductase, which yielded another Mo(V) signal designated "slow" type Q upon reduction with dithionite. Desulfo quinoline oxidoreductase was partially reactivated by incubation with sulfide.
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Affiliation(s)
- B Tshisuaka
- Fachrichtung Biophysik und Physikalische Grundlagen der Medizin, Universität des Saarlandes, Germany
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513
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Boronin AM, Filonov AE, Gayazov RR, Kulakova AN, Mshensky YN. Growth and plasmid-encoded naphthalene catabolism of Pseudomonas putida in batch culture. FEMS Microbiol Lett 1993; 113:303-7. [PMID: 8270196 DOI: 10.1111/j.1574-6968.1993.tb06531.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The growth characteristics of Pseudomonas putida plasmid-harbouring strains which catabolize naphthalene via various pathways in batch culture with naphthalene as the sole source of carbon and energy have been investigated. The strains under study were constructed using the host strain P. putida BS394 which contained various naphthalene degradation plasmids. The highest specific growth rate was ensured by the plasmids that control naphthalene catabolism through the meta-pathway of catechol oxidation. The strains metabolizing catechol via the ortho-pathway grew at a lower rate. The lowest growth rate was observed with strain BS291 harbouring plasmid pBS4 which controls naphthalene catabolism via the gentistic acid pathway. Various pathways of naphthalene catabolism appear to allow these strains to grow at various rates which should be taken into account when constructing efficient degraders of polycyclic aromatic compounds.
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Affiliation(s)
- A M Boronin
- Laboratory of Plasmid Biology, Russian Academy of Sciences, Pushchino, Moscow Region
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514
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de Lorenzo V, Cases I, Herrero M, Timmis KN. Early and late responses of TOL promoters to pathway inducers: identification of postexponential promoters in Pseudomonas putida with lacZ-tet bicistronic reporters. J Bacteriol 1993; 175:6902-7. [PMID: 8226632 PMCID: PMC206815 DOI: 10.1128/jb.175.21.6902-6907.1993] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Transcriptional lacZ fusions to the Pu and Pm promoters of the TOL (toluene degradation) plasmid inserted in monocopy in the chromosome of Pseudomonas putida showed a very different responsiveness to their respective aromatic effectors regarding growth phase. While a substantial XylS-dependent activation of Pm-lacZ was detected nearly instantly after m-toluate addition, XylR- and xylene-mediated induction of the sigma 54 promoter Pu became significant only after cells slowed down exponential growth and entered stationary phase. When Pu and Pm were fused to lacZ-tet reporters (i.e., promoterless lacZ genes coupled to a tet gene which confers resistance to tetracycline when cotranscribed with the leading gene) instead of lacZ alone, the resulting colonies displayed a distinct phenotype consisting of hyperfluorescence on agar plates after being sprayed with 4-methylumbelliferyl-beta-D-galactoside, simultaneously with being either sensitive (Pu) or resistant (Pm) to tetracycline. To examine whether the same phenotype could be scored in strains carrying transcriptional fusions of the lacZ-tet cassettes to other genes or promoters whose expression is silenced during growth and activated in stationary phase, we constructed mini-Tn5 lacZ-tet transposons for random genetic probing of promoters preferentially active at advanced stages of growth. Chromosomal insertions of this mobile element were selected by means of the constitutive resistance to kanamycin which is also specified by the transposon. A number of kanamycin-resistant colonies which are hyperfluorescent with 4-methylumbelliferyl-beta-D-galactosidase but sensitive to tetracycline and which reached full induction only at postexponential growth stages were obtained.
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Affiliation(s)
- V de Lorenzo
- Centro de Investigaciones Biológicas CSIC, Madrid, Spain
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515
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Abstract
Atmospheres containing concentrations of CO2 as low as 20% (balance nitrogen) inhibited the growth of Pseudomonas fluorescens and Pseudomonas putida on the surface of buffered Brain Heart Infusion agar plates, pH 6.8, incubated at 5 or 15 degrees C in flexible packages. The modified atmospheres decreased the growth rates and reduced the populations attained at the end of the exponential phase of growth, but had no substantial effect on the lag phase. P. fluorescens was less tolerant of CO2 than P. putida. The inhibitory effect of CO2 increased with its concentration and inhibition was greater at 5 than at 15 degrees C. Growth occurred in packages flushed with 20, 40 and 100% CO2 and 100% N2 at 15 degrees C and 20 and 40% CO2 and 100% N2 at 5 degrees C. The residual O2 concentration in the packages after flushing was 0.2-0.5%. Storage of pseudomonads in CO2 under conditions that prevented growth (e.g., 100% CO2, 5 degrees C) did not cause substantial loss of viability. There was no detectable residual effect of CO2. If cultures were incubated in air after storage for up to 70 days in CO2-containing atmospheres which prevented growth, the subsequent growth curve did not differ noticeably from that observed when plates were incubated in air immediately after inoculation. When cultures in the exponential or stationary phases of growth in modified atmospheres were transferred to air, growth rates increased quickly to rates similar to those observed in air and the final populations observed in air were attained. A reduction in the pH of the medium to 5.5 substantially increased the inhibitory effect of CO2. At 5 degrees C and pH 5.5, substantial growth of P. fluorescens was not observed in any of the CO2 concentrations tested, nor in 40 or 100% CO2 for P. putida.
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Affiliation(s)
- M J Eyles
- CSIRO Division of Food Processing, North Ryde, New South Wales, Australia
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516
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Smets BF, Rittmann BE, Stahl DA. The specific growth rate of Pseudomonas putida PAW1 influences the conjugal transfer rate of the TOL plasmid. Appl Environ Microbiol 1993; 59:3430-7. [PMID: 8250565 PMCID: PMC182470 DOI: 10.1128/aem.59.10.3430-3437.1993] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The kinetics of the conjugal transfer of a TOL plasmid were investigated by using Pseudomonas putida PAW1 as the donor strain and P. aeruginosa PAO 1162 as the recipient strain. Short-term batch mating experiments were performed in a nonselective medium, while the evolution of the different cell types was determined by selective plating techniques. The experimental data were analyzed by using a mass action model that describes plasmid transfer kinetics. This method allowed analysis of the mating experiments by a single intrinsic kinetic parameter for conjugal plasmid transfer. Further results indicated that the specific growth rate of the donor strain antecedent to the mating experiment had a strong impact on the measured intrinsic plasmid transfer rate coefficient, which ranged from 1 x 10(-14) to 5 x 10(-13) ml per cell per min. Preliminary analysis suggested that the transfer rates of the TOL plasmid are large enough to maintain the TOL plasmid in a dense microbial community without selective pressures.
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Affiliation(s)
- B F Smets
- Department of Civil Engineering, University of Illinois, Urbana 61801
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517
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Weber FJ, Ooijkaas LP, Schemen RM, Hartmans S, de Bont JA. Adaptation of Pseudomonas putida S12 to high concentrations of styrene and other organic solvents. Appl Environ Microbiol 1993; 59:3502-4. [PMID: 8250572 PMCID: PMC182484 DOI: 10.1128/aem.59.10.3502-3504.1993] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Pseudomonas putida S12 could adapt to grow on styrene in a two-phase styrene-water system. Acetate was toxic for P. putida S12, but cells were similarly able to adapt to higher acetate concentrations. Only by using these acetate-adapted cells was growth observed in the presence of supersaturating concentrations of toxic nonmetabolizable solvents such as toluene.
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Affiliation(s)
- F J Weber
- Department of Food Science, Agricultural University, Wageningen, The Netherlands
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518
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Fetzner S, Vogler B, Lingens F. Transformation of 2-chloroquinoline to 2-chloro-cis-7,8-dihydro-7,8- dihydroxyquinoline by quinoline-grown resting cells of Pseudomonas putida 86. FEMS Microbiol Lett 1993; 112:151-7. [PMID: 8405957 DOI: 10.1111/j.1574-6968.1993.tb06441.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Resting cells of Pseudomonas putida strain 86 were grown on quinoline transformed 2-chloroquinoline to 2-chloro-cis-7,8-dihydro-7,8-dihydroxyquinoline which was not converted further. 7,8-Dioxygenating activity was present when the enzymes of quinoline catabolism were induced. Quinoline-grown cells of strain 86 treated simultaneously with 2-chloroquinoline and D-(-)-threo-chloramphenicol to prevent protein biosynthesis also formed the cis-7,8-dihydrodiol of 2-chloroquinoline. Succinate-grown resting cells did not oxidize 2-chloroquinoline. Acid-catalyzed decomposition of 2-chloro-cis-7,8-dihydro-7,8-dihydroxyquinoline predominantly yielded 2-chloro-8-hydroxyquinoline. By analogy, accumulation of the putative dead-end metabolite 1H-8-hydroxy-2-oxoquinoline during growth of P. putida 86 on quinoline is suggested to likewise result from dehydration of the 7,8-dihydrodiol of 1H-2-oxoquinoline.
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Affiliation(s)
- S Fetzner
- Institut für Mikrobiologie, Universität Hohenheim, Stuttgart, FRG
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519
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Brenner V, Hernandez BS, Focht DD. Variation in chlorobenzoate catabolism by Pseudomonas putida P111 as a consequence of genetic alterations. Appl Environ Microbiol 1993; 59:2790-4. [PMID: 8215353 PMCID: PMC182367 DOI: 10.1128/aem.59.9.2790-2794.1993] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Pseudomonas putida P111 is able to utilize a broad range of monochlorinated, dichlorinated, and trichlorinated benzoates. The involvement of two separate dioxygenases was noted from data on plasmid profiles and DNA hybridization. The benzoate dioxygenase, which converts 3-chlorobenzoate (3-CB), 4-CB, and benzoate to the corresponding catechols via reduction of a dihydrodiol, was shown to be chromosomally coded. The chlorobenzoate-1,2-dioxygenase that converts ortho-chlorobenzoates to the corresponding catechols without the need of a functional dioldehydrogenase was shown to be encoded on plasmid pPB111 (75 kb). Cured strains were unable to utilize ortho-chlorobenzoates for growth. DNA hybridization data indicated that catabolism of the corresponding chlorocatechols was coded on chromosomal genes. Maintenance of plasmid pPB111 was dependent on the presence of ortho-chlorobenzoates in the growth media. A unique variant of P111 (P111D), able to grow on 3,5-dichlorobenzoate (3,5-DCB), was obtained by continuous subculturing from media containing progressively lower and higher concentrations of 3-CB and 3,5-DCB, respectively. The low frequency of segregants able to grow on 2,5-DCB, 2,3-DCB, and 2,3, 5-trichlorobenzoate was evident by lag periods greater than 200 h. Continued subculture on 3,5-DCB resulted in the formation of new plasmid pPH111 (120 kb), which was homologous to pPB111. A probe from the clc operon, which encodes for the chlorocatechol pathway, hybridized to plasmid pPH111 and to the chromosome of the wild-type strain P111 but not to its plasmid pPB111 nor to the chromosome of strain P111A, which had lost the ability to utilize chlorobenzoates.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- V Brenner
- Department of Soil and Environmental Sciences, University of California, Riverside 92521
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520
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Abstract
Pseudomonas putida, capable of utilizing acetonitrile as a sole source of carbon and nitrogen, was isolated from contaminated soil and water samples collected from industrial sites. The P. putida cells were immobilized in calcium alginate beads. The degradation of acetonitrile by the immobilized cells of P. putida was investigated. The immobilized cells degraded different concentrations of acetonitrile into ammonia and carbon dioxide. The effect of aeration on the degradation rate was also studied. Oxygen limitation was suggested in the alginate-immobilized system. The rate of degradation of acetonitrile increased with increase in the rate of aeration.
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Affiliation(s)
- K D Chapatwala
- Division of Natural Sciences, Selma University, AL 36701
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521
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Chao WL, Wang BW. In vitro and in situ survivals of bacterial populations added to fresh water environments. Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi 1993; 26:108-15. [PMID: 7982366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The fate of Aeromonas hydrophila, Alcaligenes denitrificans, Vibrio cholerae non-01, Pseudomonas putida and four different isolates of Escherichia coli in fresh river water were assessed by using different microcosms (i.e., membrane diffusion chamber and Erlenmeyer flask). When water samples were incubated at 16 +/- 1 degrees C, the differences in extent of survival among test bacteria were in general not significant. If the incubation temperature was raised to 29 +/- 1 degrees C, in the in situ studies, none of the added bacterial population could be detected by Day 3. In the in vitro studies, two of the four E. coli tested remained detectable by Day 3. Similarly, populations of the introduced A. hydrophila, P. putida and A. denitrificans were still detectable by Day 5. In general, all test bacteria survived better under low incubation temperature, regardless of whether the experiments were carried out under in vitro or in situ conditions. The results clearly indicated that when studying the fate of the introduced bacteria in the aquatic environment, in situ study was definitely required, especially in the summer time.
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Affiliation(s)
- W L Chao
- Department of Microbiology, Soochow University, Taipei, Taiwan, Republic of China
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522
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Buell CR, Anderson AJ. Expression of the aggA locus of Pseudomonas putida in vitro and in planta as detected by the reporter gene, xylE. Mol Plant Microbe Interact 1993; 6:331-340. [PMID: 8324250 DOI: 10.1094/mpmi-6-331] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In vitro agglutinability by Pseudomonas putida, isolate Corvallis, with a plant root surface agglutinin is correlated with rapid adhesion of cells of the fluorescent pseudomonad to bean (Phaseolus vulgaris) root surfaces. Agglutinability in P. putida cells is regulated by nutrient status as well as growth phase. Cells grown in three different nutrient complex media are agglutinable at early and mid-late logarithmic phase but become nonagglutinable at stationary phase. Cells grown in a minimal medium are weakly agglutinable, but the addition of lysine, aspartic acid, or histidine increases agglutinability. Cells in the same minimal medium supplemented with bean root surface components grow in a highly agglutinated state. Previous data indicate both agglutination and rapid adhesion to roots by P. putida Corvallis involves the aggA locus, which contains two putative open reading frames (ORF), ORF-AGG1 and ORFAGG2, on complementary strands. Sequence and deletion analyses suggest ORFAGG1 is the most probable ORF responsible for agglutination and adhesion. Chimeric fusion of an Escherichia coli lac promoter with ORFAGG1, but not with ORFAGG2, complemented agglutinability of an aggA::Tn5 P. putida Agg mutant, providing further evidence that ORFAGG1, not ORFAGG2, is responsible for agglutination. Heterologous expression of ORFAGG1 yields a 50-kDa precursor and a 48-kDa mature periplasmic protein. Fusions of ORFAGG1 and ORFAGG2 to the reporter gene, xylE, and detection of the reporter enzyme, catechol-2,3-oxygenase reveal an active promoter in the 5' noncoding region of ORFAGG1. The ORFAGG1 promoter is active during growth of the cells in liquid culture and is regulated by growth medium. Greatest activity of the catechol-2,3-oxygenase is observed in stationary phase when the cells are nonagglutinable. Expression of the ORFAGG1 promoter is detected in P. putida cells extracted from the root surface of bean at 48 and 72 hr after inoculation.
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Affiliation(s)
- C R Buell
- Department of Biology, Utah State University, Logan 84322-5305
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523
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Hickey WJ, Searles DB, Focht DD. Enhanced mineralization of polychlorinated biphenyls in soil inoculated with chlorobenzoate-degrading bacteria. Appl Environ Microbiol 1993; 59:1194-200. [PMID: 8476293 PMCID: PMC202260 DOI: 10.1128/aem.59.4.1194-1200.1993] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
An Altamont soil containing no measurable population of chlorobenzoate utilizers was examined for the potential to enhance polychlorinated biphenyl (PCB) mineralization by inoculation with chlorobenzoate utilizers, a biphenyl utilizer, combinations of the two physiological types, and chlorobiphenyl-mineralizing transconjugants. Biphenyl was added to all soils, and biodegradation of 14C-Aroclor 1242 was assessed by disappearance of that substance and by production of 14CO2. Mineralization of PCBs was consistently greatest (up to 25.5%) in soils inoculated with chlorobenzoate degraders alone. Mineralization was significantly lower in soils receiving all other treatments: PCB cometabolizer (10.7%); chlorobiphenyl mineralizers (8.7 and 14.9%); and mixed inocula of PCB cometabolizers and chlorobenzoate utilizers (11.4 and 18.0%). However, all inoculated soils had higher mineralization than did the uninoculated control (3.1%). PCB disappearance followed trends similar to that observed with the mineralization data, with the greatest degradation occurring in soils inoculated with the chlorobenzoate-degrading strains Pseudomonas aeruginosa JB2 and Pseudomonas putida P111 alone. While the mechanism by which the introduction of chlorobenzoate degraders alone enhanced biodegradation of PCBs could not be elucidated, the possibility that chlorobenzoate inoculants acquired the ability to metabolize biphenyl and possibly PCBs was explored. When strain JB2, which does not utilize biphenyl, was inoculated into soil containing biphenyl and Aroclor 1242, the frequency of isolates able to utilize biphenyl and 2,5-dichlorobenzoate increased progressively with time from 3.3 to 44.4% between 15 and 48 days, respectively. Since this soil contained no measurable level of chlorobenzoate utilizers yet did contain a population of biphenyl utilizers, the possibility of genetic transfer between the latter group and strain JB2 cannot be excluded.
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Affiliation(s)
- W J Hickey
- Department of Soil and Environmental Science, University of California, Riverside 92521
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524
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Jones KH, Smith RT, Trudgill PW. Diketocamphane enantiomer-specific 'Baeyer-Villiger' monooxygenases from camphor-grown Pseudomonas putida ATCC 17453. J Gen Microbiol 1993; 139:797-805. [PMID: 8515237 DOI: 10.1099/00221287-139-4-797] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Pseudomonas putida ATCC 17453 grew with either (+)- or (-)-camphor as sole carbon source. Enantiomer-specific 'biological Baeyer-Villiger' monooxygenases were synthesized irrespective of the camphor isomer used for growth. The two enzymes are probably the products of separate genes but showed many similarities. Each consisted of two electrophoretically identical subunits, bound flavin mononucleotide (FMN) non-covalently and accepted electrons from an induced NADH dehydrogenase which interacted with the FMN bound to the oxygenating component. They showed minor differences in M(r) with 3,6-diketocamphane 1,6-monooxygenase being the smaller enzyme. Isoelectric focussing showed the two enzymes to have different acidic pI values. Polyclonal antibodies raised against 3,6-diketocamphane 1,6-monooxygenase also cross-reacted with 2,5-diketocamphane 1,2-monooxygenase and its subunits.
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Affiliation(s)
- K H Jones
- Department of Biochemistry, University of Wales, Aberystwyth, UK
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525
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Stabnikova EV, Ivanov VN, Gregirchak NN, Dul'gerov AN. [The use of the neustonic forms of bacilli for purifying and decontaminating reservoirs]. Mikrobiol Zh (1978) 1993; 55:88-94. [PMID: 8497205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
It is shown possible to select the bacterial strains which are neuston ones, i.e., concentrating on the water-atmosphere interface. The preparation based on the neuston form of Bacillus megaterium is more efficient for purification of water polluted with oil hydrocarbons than the preparation based on the planktonic form of the same culture. Preparation based on the neuston form of the aerobic spore-forming bacteria is effective for biological decontamination of sewage treated using conventional methods. Application of neuston bacterial forms permits intensifying the microbiological processes in the thin (15-40 microM) surface layer of water bodies.
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526
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Hardy GP, Teixeira de Mattos MJ, Neijssel OM. Energy conservation by pyrroloquinoline quinol-linked xylose oxidation in Pseudomonas putida NCTC 10936 during carbon-limited growth in chemostat culture. FEMS Microbiol Lett 1993; 107:107-10. [PMID: 8385642 DOI: 10.1111/j.1574-6968.1993.tb06012.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
When grown in carbon source-limited chemostat cultures with lactate or glucose as the carbon and energy source and xylose as an additional source of reducing equivalents. Pseudomonas putida NCTC 10936 oxidized xylose to xylonolactone and xylonate. No other products were formed from this pentose, nor was it incorporated into biomass. The presence of xylose in these cultures resulted in higher Yglucose and Ylactate values as compared to cultures without xylose indicating that biologically useful energy was conserved during the periplasmic oxidation of xylose. As the Y0 values for growth on glucose or on lactate alone were equal to the Y0 values for growth with xylose as co-substrate, it is concluded that for glucose- or lactate-limited growth energy conservation by PQQH2 oxidation is as efficient as by NADH2 oxidation.
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Affiliation(s)
- G P Hardy
- Department of Microbiology, University of Amsterdam, Netherlands
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527
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Jurkevitch E, Hadar Y, Chen Y, Chino M, Mori S. Indirect utilization of the phytosiderophore mugineic acid as an iron source to rhizosphere fluorescent Pseudomonas. Biometals 1993; 6:119-23. [PMID: 8358206 DOI: 10.1007/bf00140113] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The phytosiderophore mugineic acid (MA) was studied as a source of iron for rhizosphere fluorescent pseudomonads. 55Fe supplied as Fe-MA was taken up by Pseudomonas putida WCS358, B10 and St3 grown under iron deficient conditions. The uptake decreased when the bacteria were grown in the presence of iron. However, no differences in uptake were observed when a siderophore deficient mutant was tested. Since ligand exchange between pseudobactin and MA was shown to occur rapidly with a half-life of 2 h, MA mediated iron uptake probably proceeds through this indirect mechanism. The ecological implications of these findings are discussed.
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Affiliation(s)
- E Jurkevitch
- Department of Plant Pathology and Microbiology, Seagram Center for Soil and Water Sciences, Faculty of Agriculture, Hebrew University of Jerusalem, Rehovot, Israel
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528
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Coco WM, Rothmel RK, Henikoff S, Chakrabarty AM. Nucleotide sequence and initial functional characterization of the clcR gene encoding a LysR family activator of the clcABD chlorocatechol operon in Pseudomonas putida. J Bacteriol 1993; 175:417-27. [PMID: 8419291 PMCID: PMC196156 DOI: 10.1128/jb.175.2.417-427.1993] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The 3-chlorocatechol operon clcABD is central to the biodegradative pathway of 3-chlorobenzoate. The clcR regulatory gene, which activates the clcABD operon, was cloned from the region immediately upstream of the operon and was shown to complement an insertion mutation for growth on 3-chlorobenzoate. ClcR activated the clcA promoter, which controls expression of the clcABD operon, in trans by 14-fold in an in vivo promoter probe assay in Pseudomonas putida when cells were incubated with 15 mM 3-chlorobenzoic acid. Specific binding of ClcR to the clcR-clcA intergenic promoter region was observed in a gel shift assay. Nucleotide sequence analysis of the clcR gene predicts a polypeptide of 32.5 kDa, which was confirmed by using specific in vivo 35S labeling of the protein from a T7 promoter-controlled ATG fusion construct. ClcR shares high sequence identity with the LysR family of bacterial regulator proteins and has especially high homology to a subgroup of the family consisting of TcbR (57% amino acid sequence identity), TfdS, CatR, and CatM. ClcR was shown to autoregulate its own production in trans to 35% of unrepressed levels but partially relieved this autorepression under conditions that induced transcription at the clcA promoter. Several considerations indicate that the clcR-clcABD locus is most similar to the tcbR-tcbCDEF regulon.
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Affiliation(s)
- W M Coco
- Department of Microbiology and Immunology, University of Illinois, Chicago 60612
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529
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Arunachalam U, Massey V, Vaidyanathan CS. p-Hydroxyphenylacetate-3-hydroxylase. A two-protein component enzyme. J Biol Chem 1992; 267:25848-55. [PMID: 1464599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
p-Hydroxyphenylacetate-3-hydroxylase, an inducible enzyme isolated from the soil bacterium Pseudomonas putida, catalyzes the conversion of p-hydroxyphenylacetate to 3,4-dihydroxyphenylacetate. The enzyme requires two protein components: a flavoprotein and a colorless protein referred to as the coupling protein. The flavoprotein alone in the presence of p-hydroxyphenylacetate and substrate analogs catalyzes the wasteful oxidation of NADH with the stoichiometric generation of H2O2. A 1:1 complex of the flavoprotein and coupling protein is required for stoichiometric product formation. Such complex formation also eliminates the nonproductive NADH oxidase activity of the flavoprotein. A new assay measuring the product formation activity of the enzyme was developed using homoprotocatechuate-2,3-dioxygenase, as monitoring the oxidation of NADH was not sufficient to demonstrate enzyme activity. The coupling protein does not seem to have any redox center in it. Thus, this 2-component flavin hydroxylase resembles the other aromatic hydroxylases in that the only redox chromophore present is FAD.
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Affiliation(s)
- U Arunachalam
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor 48109-0606
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530
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Affiliation(s)
- J L Lock
- School of Biological Sciences, University of Bath, Claverton Down, UK
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531
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Morgan JA, Rhodes G, Pickup RW, Winstanley C, Saunders JR. The effect of microcosm design on the survival of recombinant Pseudomonas putida in lake water. Microb Releases 1992; 1:155-9. [PMID: 1342636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The survival of Pseudomonas putida marked with the xylE gene was monitored in lake-water microcosms. Various designs of microcosms were compared. These ranged from 250-ml conical flasks containing 100 ml surface lake water to 12-1 glass containers with lake water overlying sediment, continuous aeration and a supply of fresh surface lake water. The presence of a low flow-through rate was shown to have little effect on the survival of P. putida. An increase in the size of microcosm, presence of sediment and aeration had a significant effect on survival in lake water and increased the rate of decline of released cells. The implication of these results in predicting the survival of P. putida in lake water using microcosms is discussed.
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Affiliation(s)
- J A Morgan
- Freshwater Biological Association, Ambleside, Cumbria, UK
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532
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Sobecky PA, Schell MA, Moran MA, Hodson RE. Adaptation of model genetically engineered microorganisms to lake water: growth rate enhancements and plasmid loss. Appl Environ Microbiol 1992; 58:3630-7. [PMID: 1482185 PMCID: PMC183154 DOI: 10.1128/aem.58.11.3630-3637.1992] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
When a genetically engineered microorganism (GEM) is released into a natural ecosystem, its survival, and hence its potential environmental impact, depends on its genetic stability and potential for growth under highly oligotrophic conditions. In this study, we compared plasmid stability and potential for growth on low concentrations of organic nutrients of strains of Pseudomonas putida serving as model GEMs. Plasmid-free and plasmid-bearing (NAH7) prototrophic isogenic strains and two amino-acid auxotrophs, all containing antibiotic resistance markers, were held physically separate from but in chemical contact with lake water containing the natural bacterium-sized microbial populations. Cells were reisolated at intervals over a 2-month period to determine the percent retaining the plasmid and the specific growth rate on various media. Plasmid stability in lake water was strongly strain specific; the NAH7 plasmid was stably maintained by the prototrophic strain for the duration of the test but was lost within 24 h by both of the auxotrophs. Specific growth rates of reisolates, compared with those of the corresponding non-lake water-exposed strains (i.e., parental strains), were not different when measured in rich medium (Luria-Bertani broth). However, specific growth rates were 42, 55, and 63% higher in reisolates of auxotrophs and the plasmid-free prototroph, respectively, when measured in 10-fold-diluted medium after exposure of 15 days or longer to lake water. Moreover, lake water-exposed strains grew actively when reintroduced into sterile lake water (28- to 33-fold increase in numbers over 7 days), while the corresponding unadapted parental strains exhibited no growth over the same period.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P A Sobecky
- Department of Microbiology, University of Georgia, Athens 30602
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533
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Abstract
Conditional lethal (suicidal) genetic constructs were designed and employed in strains of Pseudomonads as models for containment of genetically-engineered microbes that may be deliberately released into the environment. A strain of Pseudomonas putida was formed with a suicide vector designated pBAP24h that was constructed by cloning the host killing gene (hok) into the RSF1010 plasmid pVDtac24 and placing it under the control of the tac promoter. After hok induction in P. putida only 40% of surviving cells continued to bear the hok sequences within 4 h of induction; in contrast, 100% of the cells in uninduced controls bore hok. A few survivors that demonstrated resistance to hok-induced killing developed in P. putida, which may have been due to a mutation or physiological adaptation that rendered the membrane 'resistant' to hok. Conditional lethal strains of P. putida also were formed by inserting gef (a chromosomal homolog of hok) under the control of the tac promoter into the chromosome using a transposon. Constructs with chromosomal gef, as well as an RK2-derived plasmid construct containing gef, were only marginally more stable than the hok constructs; they were effective in killing P. putida when induced and within 2 h post-induction killing from either gef construct resulted in a 10(3)-10(5)-fold reduction in viable cell count compared to uninduced controls.
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Affiliation(s)
- A K Bej
- Department of Biology, University of Louisville, Kentucky 40292
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534
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Höfle MG. Bacterioplankton community structure and dynamics after large-scale release of nonindigenous bacteria as revealed by low-molecular-weight-RNA analysis. Appl Environ Microbiol 1992; 58:3387-94. [PMID: 1280060 PMCID: PMC183108 DOI: 10.1128/aem.58.10.3387-3394.1992] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A set of freshwater mesocosms (1.7 m3 each) was inoculated with large amounts of Escherichia coli, Pseudomonas putida, and their culture medium to substantially disturb the natural microbial community. To monitor microbial community dynamics, low-molecular-weight RNA (5S rRNA and tRNA) obtained directly from bacterioplankton was analyzed by using high-resolution electrophoresis. The introduced bacteria showed no significant effect on the community structure of the natural bacterial assemblage and its dynamics for 16 days. In contrast, the addition of culture medium resulted within 2 days in a reduction of community diversity due to dominance of a single 5S rRNA band from an indigenous bacterium. Partial sequencing of several 5S rRNAs demonstrated the molecular homogeneity of most of the abundant bands and enabled the identification of corresponding bacterial isolates and/or species. The dominating bacterium (around 54% of the total 5S rRNA) in the nutrient-amended mesocosms could be identified by partial sequencing as a member of the Aeromonas hydrophila complex. Another bloom of heterotrophic bacteria belonging to the Cytophaga johnsonae complex was detected in the nutrient-amended mesocosms after 13 days. The dominance of this C. johnsonae-like bacterium could even be seen in the environmental tRNAs of the bacterioplankton, where its specific tRNAs prevailed from day 13 onward. This event was also independent of the introduced nonindigenous bacteria because it occurred at the same time in all nutrient-amended mesocosms. By contrast, in the unamended experiments, a different small 5S rRNA could by observed from day 10 onward with less pronounced dominance.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M G Höfle
- Max-Planck-Institut für Limnologie, Plön, Germany
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535
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Cruden DL, Wolfram JH, Rogers RD, Gibson DT. Physiological properties of a Pseudomonas strain which grows with p-xylene in a two-phase (organic-aqueous) medium. Appl Environ Microbiol 1992; 58:2723-9. [PMID: 1444381 PMCID: PMC182999 DOI: 10.1128/aem.58.9.2723-2729.1992] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Pseudomonas putida Idaho utilizes toluene, m-xylene, p-xylene, 1,2,4-trimethylbenzene, and 3-ethyltoluene as growth substrates when these hydrocarbons are provided in a two-phase system at 5 to 50% (vol/vol). Growth also occurs on Luria-Bertani medium in the presence of a wide range of organic solvents. The ability of the organism to grow in the presence of organic solvents is correlated with the logarithm of the octanol-water partition coefficient, with dimethyl-phthalate (log P(OCT) = 2.3) being the most polar solvent tolerated. During growth with p-xylene (20% [vol/vol]), there was an initial lag period accompanied by cell death, which was followed by a period of exponential growth. The stationary phase of growth was characterized by a dramatic decrease in cell viability, although cell dry weight and turbidity measurements slowly increased. Electron micrographs revealed that during growth in the presence of p-xylene, the outer cell membrane becomes convoluted and membrane fragments are shed into the culture medium. At the same time, the cytoplasmic membrane invaginates, forming vesicles, and becomes disorganized. Electron-dense intracellular inclusions were observed in cells grown with p-xylene (20% [vol/vol]) and p-xylene vapors, which are not present in cells grown with succinate. Attempts to demonstrate the presence of plasmid DNA in P. putida Idaho were negative. However, polarographic studies indicated that the organism utilizes the same pathway for the degradation of toluene, m-xylene, and p-xylene as that used by P. putida mt-2 which contains the TOL plasmid pWWO.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- D L Cruden
- Department of Microbiology, University of Iowa, Iowa City 52242
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536
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Sedina SA. [The kinetics of glycol destruction by a Pseudomonas putida BS-2 strain]. Mikrobiol Zh (1978) 1992; 54:53-9. [PMID: 1453991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Destruction of ethylene glycol and diethylene glycol by Pseudomonas putida BS-2 culture under conditions of its batch cultivation has been studied for its physiological regularities. The specific rate of the biomass growth in the region of limiting substrate concentrations depends on the diethylene glycol concentration in the medium and follows the Mono equation. A semisaturation constant for diethylene glycol is 209 +/- 17 mg/d. The specific rate of the culture growth is independent of the ethylene glycol concentration in the medium within a wide range from 0.08 to 10 g/l. Kinetics of the bacteria growth inhibition by excess of substrates is a complex character and obeys none of the known models of the substrate inhibition.
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537
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Brinkmann U, Reineke W. Degradation of chlorotoluenes by in vivo constructed hybrid strains: problems of enzyme specificity, induction and prevention of meta-pathway. FEMS Microbiol Lett 1992; 75:81-7. [PMID: 1526468 DOI: 10.1016/0378-1097(92)90460-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The activities of the TOL plasmid-coded xylene oxygenase, benzylalcohol dehydrogenase, benzaldehyde dehydrogenase of Pseudomonas putida strain PaW1 were tested with substituted toluenes, benzylalcohols and benzaldehydes, respectively, as substrates. Several chlorinated toluenes were shown to induce enzymes of the xylene degradation sequence. Conjugative transfer of the TOL plasmid from Pseudomonas putida strain PaW1 to Pseudomonas sp. strain B13 and Pseudomonas cepacia strain JH230 allowed the isolation of hybrid strains capable of growing in the presence of 3-chloro-, 4-chloro- and 3,5-dichlorotoluene. Hybrid strains revealed new ways to prevent the dead-end meta-pathway for cholorocatechols.
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Affiliation(s)
- U Brinkmann
- Bergische Universität-Gesamthochschule Wuppertal, Chemische Mikrobiologie, FRG
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538
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Sedina SA. [The effect of physicochemical factors on the growth of Pseudomonas putida BS-2 on a medium with diethylene glycol]. Mikrobiol Zh (1978) 1992; 54:43-8. [PMID: 1406384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The physicochemical factors of medium have been studied for their effect on the physiological indices of growth of Pseudomonas putida BS-2 culture utilizing diethylenglycol as the only source of carbon. Action of the supraoptimal temperature on the growth process of P. putida BS-2 is accompanied by a decrease (more than twice) in economic coefficient of substrate and specific growth rate as compared with their maximal values. Dependences of specific growth rate of P. putida BS-2 in the medium with diethylenglycol on the presence of NaCl in it within the range of its concentrations from 0 to 4% and methanol in the concentration range of 0-20 g/l follow the noncompetitive inhibition equation. When NaCl concentration in the medium is more than 4%, complete separation of constructive and energy metabolism processes is observed.
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539
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Abstract
Slow rehydration of bacteria from dried inoculant formulations provided higher viable counts than did rapid rehydration. Estimates were higher when clay and peat powder formulations of Rhizobium meliloti, Rhizobium leguminosarum biovar trifolii, and Pseudomonas putida, with water activities between 0.280 and 0.650, were slowly rehydrated to water activities of approximately 0.992 before continuing the dilution plating sequence. Rhizobium meliloti populations averaged 6.8 x 10(8) cfu/g and 1328 cfu/alfalfa seed greater when slowly rehydrated from bulk powder and preinoculated seeds, respectively. Bulk powder samples were slowly rehydrated to 0.992 water activity by the gradual addition of diluent, followed by a 10-min period for moisture equilibration. Preinoculated seed samples were placed in an environmental chamber at 24 degrees C with relative humidity greater than 80% for 1 h to allow moisture absorption. "Upshock," osmotic cellular stresses that occur during rehydration, was reduced when dried microbial formulations were slowly rehydrated and equilibrated before becoming fully hydrated in the dilution plating sequence. These procedures may also be applicable when estimating total viable bacterial populations from dried soil or other dry formulations.
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540
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Heller S, Bühler S, Kilz S, Mieschendahl M. Bioluminescence-based detection of genetically engineered microorganisms in nonsterile river water. Microb Releases 1992; 1:35-9. [PMID: 1341987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The luminescence genes of the marine bacterium Vibrio fischeri were cloned into a lac expression vector and introduced into Escherichia coli and Pseudomonas putida. Survival of the cells in river water samples was monitored by light measurements. Whereas E. coli survived in sterilized river water for more than 29 days, it died off in nonsterile river water after 9 to 13 days. The engineered P. putida cells survived in nonsterile river water for more than 137 days. The detection limit for E. coli was 11 cells/ml.
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Affiliation(s)
- S Heller
- Abteilung für Molekular- und Zellbiologie, Battelle-Institut e. V., Frankfurt/M, Federal Republic of Germany
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541
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Heipieper HJ, Diefenbach R, Keweloh H. Conversion of cis unsaturated fatty acids to trans, a possible mechanism for the protection of phenol-degrading Pseudomonas putida P8 from substrate toxicity. Appl Environ Microbiol 1992; 58:1847-52. [PMID: 1622260 PMCID: PMC195693 DOI: 10.1128/aem.58.6.1847-1852.1992] [Citation(s) in RCA: 290] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A trans unsaturated fatty acid was found as a major constituent in the lipids of Pseudomonas putida P8. The fatty acid was identified as 9-trans-hexadecenoic acid by gas chromatography, argentation thin-layer chromatography, and infrared absorption spectrometry. Growing cells of P. putida P8 reacted to the presence of sublethal concentrations of phenol in the medium with changes in the fatty acid composition of the lipids, thereby increasing the degree of saturation. At phenol concentrations which completely inhibited the growth of P. putida, the cells were still able to increase the content of the trans unsaturated fatty acid and simultaneously to decrease the proportion of the corresponding 9-cis-hexadecenoic acid. This conversion of fatty acids was also induced by 4-chlorophenol in nongrowing cells in which the de novo synthesis of lipids had stopped, as shown by incorporation experiments with labeled acetate. The isomerization of the double bond in the presence of chloramphenicol indicates a constitutively operating enzyme system. The cis-to-trans modification of the fatty acids studied here apparently is a new way of adapting the membrane fluidity to the presence of phenols, thereby compensating for the elevation of membrane permeability induced by these toxic substances.
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Affiliation(s)
- H J Heipieper
- Department of Microbiology, University of Muenster, Germany
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542
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Abstract
The effects of the antiarthritic drugs aurothiomalate (AuTm), aurothioglucose (AuTg), auranofin, its metabolite triethylphosphinegold(I)thioglucose (Et3PAuTg), and several related complexes on the growth of Pseudomonas putida were studied. Two strains were used, one of which (BK135) was more sensitive to Et3PAuTg (tolerant up to 4 microM) than the other (BK403; tolerant to at least 500 microM). Gold thiolate complexes and thiolate ligands alone had little effect on growth. Gold phosphine complexes increased the length of the lag phase of growth and reduced oxygen uptake. Marked changes in cellular morphology were determined by electron microscopy. Copper(II) compounds and aurothiomalate were synergistic in their growth inhibitory effects towards these bacteria. Experiments with 195Au suggested that a mechanism does not exist for the short term (minutes) uptake of gold by sensitive or resistant bacteria, but the resistant strain appeared to limit gold uptake over a longer term (hours).
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Affiliation(s)
- M D Rhodes
- Department of Chemistry, Birkbeck College, University of London, U.K
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543
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Abstract
Biological conversion of the herbicide bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) was studied in a batch culture of Pseudomonas putida by using HPLC. The process had a cometabolic character and proceeded only in the presence of another, simultaneously metabolizable, carbon and energy source. The intensity of degradation correlated with the growth rate, the degradation stopping when the cosubstrate becomes exhausted or the pH value of the medium falls below 6.5. In a medium with glucose, no lag phase longer than one day was observed concerning growth, sugar and herbicide consumption and formation of metabolic herbicide derivatives (3,5-dibromo-4-hydroxybenzamide and 3,5-dibromo-4-hydroxybenzoic acid). In a medium with ribose, the initial lag of the above processes took 2 d. No formation of other degradation products was detected. Growth inhibition was proportional to the concentration of bromoxynil.
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Affiliation(s)
- M Vokounová
- Institute of Microbiology, Czechoslovak Academy of Sciences, Prague
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544
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Abstract
The inner membrane of the air cell of hens' eggs was inoculated with Pseudomonas putida, Staphylococcus xylosus, Enterococcus faecalis, Escherichia coli and Salmonella enteritidis. The first mentioned eventually dominated the contamination of the albumen of eggs stored at 4, 15, and 20 degrees C. The last mentioned did so in eggs stored at 37 degrees C. The interval between inoculation of the membrane and gross contamination of the albumen was markedly influenced by site of contamination relative to yolk movement.
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Affiliation(s)
- J Dolman
- School of Biological Sciences, University of Bath, Avon
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545
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Huijberts GN, Eggink G, de Waard P, Huisman GW, Witholt B. Pseudomonas putida KT2442 cultivated on glucose accumulates poly(3-hydroxyalkanoates) consisting of saturated and unsaturated monomers. Appl Environ Microbiol 1992; 58:536-44. [PMID: 1610179 PMCID: PMC195281 DOI: 10.1128/aem.58.2.536-544.1992] [Citation(s) in RCA: 229] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The biosynthesis of poly(3-hydroxyalkanoates) (PHAs) by Pseudomonas putida KT2442 during growth on carbohydrates was studied. PHAs isolated from P. putida cultivated on glucose, fructose, and glycerol were found to have a very similar monomer composition. In addition to the major constituent 3-hydroxydecanoate, six other monomers were found to be present: 3-hydroxyhexanoate, 3-hydroxyoctanoate, 3-hydroxydodecanoate, 3-hydroxydodecenoate, 3-hydroxytetradecanoate, and 3-hydroxytetradecenoate. The identity of all seven 3-hydroxy fatty acids was established by gas chromatography-mass spectrometry, one-dimensional 1H-nuclear magnetic resonance, and two-dimensional double-quantum filtered correlation spectroscopy 1H-nuclear magnetic resonance. The chemical structures of the monomer units are identical to the structure of the acyl moiety of the 3-hydroxyacyl-acyl carrier protein intermediates of de novo fatty acid biosynthesis. Furthermore, the degree of unsaturation of PHA and membrane lipids is similarly influenced by shifts in the cultivation temperature. These results strongly indicate that, during growth on nonrelated substrates, PHA monomers are derived from intermediates of de novo fatty acid biosynthesis. Analysis of a P. putida pha mutant and complementation of this mutant with the cloned pha locus revealed that the PHA polymerase genes necessary for PHA synthesis from octanoate are also responsible for PHA formation from glucose.
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Affiliation(s)
- G N Huijberts
- Agrotechnological Research Institute (ATO-DLO), Wageningen, The Netherlands
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546
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Sedina SA. [The destruction of diethylene glycol by a Pseudomonas putida BS-2 culture]. Mikrobiol Zh (1978) 1992; 54:61-7. [PMID: 1584086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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547
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Tricot C, Stalon V, Legrain C. Isolation and characterization of Pseudomonas putida mutants affected in arginine, ornithine and citrulline catabolism: function of the arginine oxidase and arginine succinyltransferase pathways. J Gen Microbiol 1991; 137:2911-8. [PMID: 1791443 DOI: 10.1099/00221287-137-12-2911] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Pseudomonas putida mutants impaired in the utilization of arginine are affected in either the arginine succinyltransferase pathway, the arginine oxidase route, or both. However, mutants affected in one of the pathways still grow on arginine as sole carbon source. Analysis of the products excreted by both wild-type and mutant strains suggests that arginine is mainly channelled by the oxidase route. Proline non-utilizing mutants are also affected in ornithine utilization, confirming the role of proline as an intermediate in ornithine catabolism. Mutants affected in ornithine cyclodeaminase activity still grow on proline and become unable to use ornithine. Both proline non-utilizing mutants and ornithine-cyclodeaminase-minus mutants are unable to use citrulline. These results, together with induction of ornithine cyclodeaminase when wild-type P. putida is grown on citrulline, indicate that utilization of citrulline as a carbon source proceeds via proline with ornithine as an intermediate. Thus in P. putida, the aerobic catabolism of arginine on the one hand and citrulline and ornithine on the other proceed by quite different metabolic segments.
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Affiliation(s)
- C Tricot
- Laboratoire de Microbiologie, Faculté des Sciences, Université Libre de Bruxelles, Belgium
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548
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Abstract
Pseudomonas putida P111 was isolated by enrichment culture on 2,5-dichlorobenzoate and was also able to grow on 2-chloro-, 3-chloro-, 4-chloro-, 2,3-dichloro-, 2,4-dichloro-, and 2,3,5-trichlorobenzoates. However, 3,5-dichlorobenzoate completely inhibited growth of P111 on all ortho-substituted benzoates that were tested. When 3,5-dichlorobenzoate was added as a cosubstrate with either 3- or 4-chlorobenzoate, cell yields and chloride release were greater than those observed from growth on either monochlorobenzoate alone. Moreover, resting cells of P111 grown on 4-chlorobenzoate released chloride from 3,5-dichlorobenzoate and produced no identifiable intermediate. In contrast, resting cells grown on 2,5-dichlorobenzoate metabolized 3,5-dichlorobenzoate without release of chloride and accumulated a degradation product, which was identified as 1-carboxy-1,2-dihydroxy-3,5-dichlorocyclohexadiene on the basis of gas chromatography-mass spectrometry confirmation of its two acid-hydrolyzed products, 3,5- and 2,4-dichlorophenol. Since 3,5-dichlorocatechol was rapidly metabolized by cells grown on 2,5-dichlorobenzoate, it is apparent that 1-carboxy-1,2-dihydroxy-3,5-dichlorocyclohexadiene is not further metabolized by these cells. Moreover, induction of a functional dihyrodiol dehydrogenase would not be required for growth of P111 on other ortho-chlorobenzoates since the corresponding chlorodihydrodiols produced from a 1,2-dioxygenase attack would spontaneously decompose to the corresponding catechols. In contrast, growth on 3-chloro-, 4-chloro-, or 3,5-dichlorobenzoate requires a functional dihydrodiol dehydrogenase, yet only the two monochlorobenzoates appear to induce for it.
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Affiliation(s)
- B S Hernandez
- Department of Microbiology, University of Panama, Republic of Panama
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549
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Stabnikova EV, Gregirchak NN, Taranenko TO, Nud'ga AI. [The autoselection of neustonic forms of bacteria]. Mikrobiol Zh (1978) 1991; 53:33-7. [PMID: 1791780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Self-breeding of neuston forms of Methylobacterium sp., Pseudomonas putida BC-2, Alcaligenes paradoxus BC-1, Bacillus thuringiensis var. israilensis bacteria as well as of a mixed culture of methylotrophs is shown possible. In spite of ability of hydrophobicity of the cell surface the suggested method of self-breeding may be used to perfect properties of larvicidal biopreparations, and bacterial preparations which intensify self-purification of water bodies.
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