Topic
Pseudomonas putida
About: Pseudomonas putida is a research topic. Over the lifetime, 6854 publications have been published within this topic receiving 230572 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: Of the known bacteria and 12 isolates tested, the most effective were nine isolates that significantly increased plant height, root and shoot biomass, and number of tillers, and the plant growth promoting effects of isolates were different in the two soils.
Abstract: The association of winter wheat (Triticum aestivum L. cv. Norstar) with root-colonizing bacteria (rhizobacteria) was studied in potted soil experiments in the growth chamber. Thirty-six known bacteria, some of which have been reported to stimulate plant growth, and 75 isolates obtained from the rhizosphere of winter wheat were tested for their effects on plant growth and development in two different soils. Two known bacteria and 12 isolates stimulated growth of winter wheat. Of these, the most effective were nine isolates that significantly (P < 0.01) increased plant height, root and shoot biomass, and number of tillers. The plant growth promoting effects of isolates were different in the two soils. Three of these strains were tentatively classified as Pseudomonas aeruginosa, and two each as Pseudomonas cepacia, Pseudomonas fluorescens, and Pseudomonas putida. Some isolates induced significant increases in seedling emergence rates and (or) demonstrated antagonism in vitro against Rhizoctonia solani and Le...
124 citations
13 Feb 2016
TL;DR: The endophytic strains effectively inhibit the growth of Escherichia coli, Klebsiella pneumoniae and some of the fungal strain like Fusarium solani and Alterneria alternata.
Abstract: Fourteen endophytic bacterial isolates were isolated from the rhizome of Curcuma longa L. were characterized on the basis of morphology, biochemical characteristics and 16S rRNA gene sequence analysis. The isolates were identified to six strains namely Bacillus cereus (ECL1), Bacillus thuringiensis (ECL2), Bacillus sp. (ECL3), Bacillus pumilis (ECL4), Pseudomonas putida (ECL5), and Clavibacter michiganensis (ECL6). All the strains produced IAA and solubilized phosphate and only two strains produced siderophore (ECL3 and ECL5) during plant growth promoting trait analysis. All the endophytic strains utilized glucose, sucrose and yeast extract as a carbon source where as glycine, alanine, cystine and glutamine as nitrogen source. The strains were mostly sensitive to antibiotic chloramphenicol followed by erythromycin while resistant to polymixin B. The endophytic strains effectively inhibit the growth of Escherichia coli, Klebsiella pneumoniae and some of the fungal strain like Fusarium solani and Alterneria alternata. The strain ECL2 and ECL4 tolerated maximum 8 % of NaCl concentration where as strains ECL5 and ECL6 6 % in salinity tolerance.
123 citations
TL;DR: In this article, a continuous degradation of phenol from 100 mg L -1 to concentrations as low as 2.5 mg L −1 using immobilized Pseudomonas putida was established.
123 citations
TL;DR: Because 2-hydroxypent-2,4-dienoate is chemically unstable, formation of a complex between the decarboxylase and the hydratase may assure efficient transformation of this unstable intermediate in vivo.
Abstract: The meta-cleavage pathway of catechol is a major mechanism for degradation of aromatic compounds. In this pathway, the aromatic ring of catechol is cleaved by catechol 2,3-dioxygenase and its product, 2-hydroxymuconic semialdehyde, is further metabolized by either a hydrolytic or dehydrogenative route. In the dehydrogenative route, 2-hydroxymuconic semialdehyde is oxidized to the enol form of 4-oxalocrotonate by a dehydrogenase and then further metabolized to acetaldehyde and pyruvate by the actions of 4-oxalocrotonate isomerase, 4-oxalocrotonate decarboxylase, 2-oxopent-4-enoate hydratase, and 4-hydroxy-2-oxovalerate aldolase. In this study, the isomerase, decarboxylase, and hydratase encoded in the TOL plasmid pWW0 of Pseudomonas putida mt-2 were purified and characterized. The 28-kilodalton isomerase was formed by association of extremely small identical protein subunits with an apparent molecular weight of 3,500. The decarboxylase and the hydratase were 27- and 28-kilodalton polypeptides, respectively, and were copurified by high-performance-liquid chromatography with anion-exchange, hydrophobic interaction, and gel filtration columns. The structural genes for the decarboxylase (xylI) and the hydratase (xylJ) were cloned into Escherichia coli. The elution profile in anion-exchange chromatography of the decarboxylase and the hydratase isolated from E. coli XylI+XylJ- and XylI-XylJ+ clones, respectively, were different from those isolated from XylI+ XylJ+ bacteria. This suggests that the carboxylase and the hydratase form a complex in vivo. The keto but not the enol form of 4-oxalocrotonate was a substrate for the decarboxylase. The product of decarboxylation was 2-hydroxypent-2,4-dienoate rather than its keto form, 2-oxopent-4-enoate. The hydratase acts on the former but not the latter isomer. Because 2-hydroxypent-2,4-dienoate is chemically unstable, formation of a complex between the decarboxylase and the hydratase may assure efficient transformation of this unstable intermediate in vivo.
123 citations
TL;DR: By using in vivo expression technology (IVET) to positively select single cell survival, 28 rap genes (root-activated promoters) preferentially expressed in the maize rhizosphere were identified, which included genes with probable functions in the cell envelope, chemotaxis and motility, transport, secretion, DNA metabolism and defense mechanism, regulation, energy metabolism, stress, detoxification, and protein synthesis.
Abstract: Pseudomonas putida KT2440, a paradigm organism in biodegradation and a good competitive colonizer of the maize rhizosphere, was the subject of studies undertaken to establish the genetic determinants important for its rhizospheric lifestyle. By using in vivo expression technology (IVET) to positively select single cell survival, we identified 28 rap genes (root-activated promoters) preferentially expressed in the maize rhizosphere. The IVET system had two components: a mutant affected in aspartate-beta-semialdehyde dehydrogenase (asd), which was unable to survive in the rhizosphere, and plasmid pOR1, which carries a promoter-less asd gene. pOR1-borne transcriptional fusions of the rap promoters to the essential gene asd, which were integrated into the chromosome at the original position of the corresponding rap gene, were active and allowed growth of the asd strain in the rhizosphere. The fact that five of the rap genes identified in the course of this work had been formerly characterized as being related to root colonization reinforced the IVET approach. Up to nine rap genes encoded proteins either of unknown function or that had been assigned an unspecific role based on conservation of the protein family domains. Rhizosphere-induced fusions included genes with probable functions in the cell envelope, chemotaxis and motility, transport, secretion, DNA metabolism and defense mechanism, regulation, energy metabolism, stress, detoxification, and protein synthesis.
123 citations