Satellite deoxyribonucleic acid in Pseudomonas aeruginosa

1972 ◽  
Vol 18 (7) ◽  
pp. 1003-1006
Author(s):  
Ruth B. Finley ◽  
J. D. Punch
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Satellite Dna ◽  
Deoxyribonucleic Acid ◽  
The Other ◽  
Clinical Specimens

Deoxyribonucleic acid preparations from two strains of Pseudomonas aeruginosa newly isolated from clinical specimens each contained double-stranded satellite DNA. The satellite DNA in one strain consisted of two components with buoyant densities of 1.705 and 1.712 g cm−3 and comprised 28% of the total extracted DNA. The other strain contained 15% satellite DNA which was composed of components with buoyant densities of 1.711 and 1.718 g cm−3.

scholarly journals Self-renaturing fractions in the separated strands of mouse satellite deoxyribonucleic acid

1972 ◽  
Vol 128 (2) ◽  
pp. 193-198 ◽  
Author(s):  
W. D. Sutton ◽  
P. M. B. Walker
Keyword(s):  
Satellite Dna ◽  
Deoxyribonucleic Acid ◽  
Gradient Centrifugation ◽  
High Thermal Stability ◽  
The Self ◽  
The Other ◽  
Cscl Gradient ◽  
Dna Strands ◽  
Variable Extent ◽  
Mouse Satellite Dna

Pyrimidine- and purine-rich strands of Mus musculus satellite DNA prepared by alkaline CsCl-gradient centrifugation can self-renature to a variable extent to give partial duplexes with high thermal stability. These duplexes were purified by treatment with nuclease S1 followed by hydroxylapatite chromatography, and have been shown by pyrimidine-tract analysis to be very similar in sequence to total reassociated satellite DNA. It is believed that the self-renaturing fractions result from variable contamination of each strand with fragments of the other, rather than from molecular inversions. The predominantly single-stranded properties of these fractions may be partly due to the ability of mouse satellite DNA strands to reassociate in non-stoicheiometric proportions.

CELLULAR DISINTEGRATION WITH CONCOMITANT RELEASE OF SLIME AND PRODUCTION OF EXTRACELLULAR MANNAN BY PSEUDOMONAS AERUGINOSA: TWO SEPARATE PHENOMENA

1964 ◽  
Vol 10 (3) ◽  
pp. 467-472 ◽  
Author(s):  
K. Jane Carson ◽  
R. G. Eagon
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Membrane ◽  
Cell Walls ◽  
Cell Membranes ◽  
Deoxyribonucleic Acid ◽  
De Novo ◽  
The Other ◽  
Experimental Intervention ◽  
Other Hand ◽  
Extracellular Slime

Pseudomonas aeruginosa strain 64 has previously been demonstrated to produce an extracellular slime material containing deoxyribonucleic acid and mannan as major constituents. Results reported here indicate that the extracellular deoxyribonucleic acid arises spontaneously from an intracellular origin owing to cellular disintegration without experimental intervention. Cellular disintegration occurs between the first and fifth days of cultivation. It is suggested that cellular disintegration may be due to lysogenic and (or) pyocinogenic phenomena.Production of extracellular mannan, on the other hand, was shown to occur during the first 24 hours of cultivation. Mannose, which was demonstrated to be a carbohydrate of the cell membrane, was not present in cells in sufficient quantity to account for total extracellular mannan. Thus, mannan was indicated to be synthesized de novo and excreted into the medium, possibly as a capsular polysaccharide.Glucose and glucosamine were the only two carbohydrates detected in hydrolysates of cell walls of P. aeruginosa strain 64, while mannose was the only carbohydrate detected in cell membranes.

Biodegradation of chlorophenols by immobilized pure-culture microorganisms

1996 ◽  
Vol 34 (10) ◽  
pp. 67-72 ◽  
Author(s):  
Lu Chih-Jen ◽  
Lee Chi-Mei ◽  
Huang Chiou-Zong
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Pseudomonas Putida ◽  
Pure Culture ◽  
The Other ◽  
Batch Reactors ◽  
Agrobacterium Radiobacter ◽  
Culture Cells ◽  
Lag Period

The biodegradation of phenol and chlorophenols by immobilized pure-culture cells was conducted by a series of batch reactors. The microorganisms used in this study were Pseudomonas putida, Psuedomonas testosteroni, Pseudomonas aeruginosa, and Agrobacterium radiobacter. All four species showed the ortho-cleavage pathway to metabolize chlorophenols. Among the four species, P. testosteroni, P. putida, and P. aeruginosa could effectively remove phenol at 200 mg/l. P. testosteroni could effectively remove 2-chlorophenol at 10mg/l. However, the other three species, P. putida, P. aeruginosa, and A. radiobacter, could not effectively remove 2-chlorophenol. Although 3-chlorophenol is a recalcitrant compound, P. testosteroni also could rapidly metabolize 3-chlorophenol at 10 mg/l. The removal of 4-chlorophenol at 10 mg/l by P. testosteroni reached 98% within one day. P. aeruginosa and A. radiobacter also could metabolize 4-chlorophenol after 2 and 7 days of lag period, respectively.

scholarly journals Revisiting the quorum-sensing hierarchy in Pseudomonas aeruginosa: the transcriptional regulator RhlR regulates LasR-specific factors

Microbiology ◽  
2009 ◽  
Vol 155 (3) ◽  
pp. 712-723 ◽  
Author(s):  
Valérie Dekimpe ◽  
Eric Déziel
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Virulence Factors ◽  
Transcriptional Regulator ◽  
Homoserine Lactone ◽  
The Other ◽  
Virulence Determinants ◽  
Late Stationary Phase ◽  
Regulatory Systems ◽  
Specific Factors

Pseudomonas aeruginosa uses the two major quorum-sensing (QS) regulatory systems las and rhl to modulate the expression of many of its virulence factors. The las system is considered to stand at the top of the QS hierarchy. However, some virulence factors such as pyocyanin have been reported to still be produced in lasR mutants under certain conditions. Interestingly, such mutants arise spontaneously under various conditions, including in the airways of cystic fibrosis patients. Using transcriptional lacZ reporters, LC/MS quantification and phenotypic assays, we have investigated the regulation of QS-controlled factors by the las system. Our results show that activity of the rhl system is only delayed in a lasR mutant, thus allowing the expression of multiple virulence determinants such as pyocyanin, rhamnolipids and C4-homoserine lactone (HSL) during the late stationary phase. Moreover, at this stage, RhlR is able to overcome the absence of the las system by activating specific LasR-controlled functions, including production of 3-oxo-C12-HSL and Pseudomonas quinolone signal (PQS). P. aeruginosa is thus able to circumvent the deficiency of one of its QS systems by allowing the other to take over. This work demonstrates that the QS hierarchy is more complex than the model simply presenting the las system above the rhl system.

Peptide synthesis in bone marrow: insulin and thyroxin effects

1962 ◽  
Vol 203 (4) ◽  
pp. 693-696 ◽  
Author(s):  
Thomas F. Necheles
Keyword(s):  
Bone Marrow ◽  
Nucleic Acid ◽  
Peptide Synthesis ◽  
Ribonucleic Acid ◽  
Deoxyribonucleic Acid ◽  
Optimum Concentration ◽  
The Other ◽  
Anabolic Effect ◽  
Oxygen Buffer

Myeloid marrow was rapidly removed from femurs of fasting young rabbits, sectioned, and incubated in Krebs-bicarbonate-CO2-oxygen buffer with appropriate C14-labeled precursors. All manipulations were designed to preserve the architecture of the tissue. After 1 hr the protein or nucleic acid-adenine was isolated and purified. Insulin, 0.01 U/ml added in vitro, stimulated histidine-2(ring)-C14 incorporation into protein by 26 ± 1.4%; alkali-treated insulin was inactive. Thyroxin elicited a 49.4 ± 2.1% stimulation at an optimum concentration of 10–7 m. Triiodothyronine, but not diiodothyronine, also had a significant effect. Insulin increased incorporation of carbon from adenosine-8-C14 into adenine of ribonucleic acid and deoxyribonucleic acid. Thyroxin, on the other hand, was without consistent effect on this process. Thyroxin stimulated significantly the incorporation of C14 of glycine-2-C14 into adenine. The possibility that part of the anabolic effect of thyroxin on bone marrow may arise from a stimulus to incorporation of precursors into purines is suggested.

scholarly journals Composition of Pseudomonas aeruginosa slime

1969 ◽  
Vol 112 (4) ◽  
pp. 521-525 ◽  
Author(s):  
M. R. W. Brown ◽  
J. H. Scott Foster ◽  
J. R. Clamp
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Hyaluronic Acid ◽  
Nucleic Acid ◽  
Growth Medium ◽  
Extraction Procedure ◽  
The Other ◽  
Minor Components ◽  
Polysaccharide Fraction ◽  
Defined Media ◽  
Rna And Dna

1. The slime produced by eight strains of Pseudomonas aeruginosa on a number of different media was demonstrated to be qualitatively the same. Small quantitative differences may be occasioned by differences in the extraction procedure, the growth medium or the strain of organism used. 2. The slime was shown to be predominantly polysaccharide with some nucleic acid material and a small amount of protein. 3. The hydrolysed polysaccharide fraction consists mainly of glucose with smaller amounts of mannose. This accounts for some 50–60% of the total slime. In addition, there is some 5% of hyaluronic acid. The nucleic acid material represents approx. 20% of the total weight, and is composed of both RNA and DNA. 4. Minor components are protein, rhamnose and glucosamine, the protein being less than 5% of the total. 5. Hyaluronic acid is produced in greater quantities from nutrient broth than from chemically defined media, and is more firmly attached to the cells than the other components.

THE ENZYMES OF THE TRICARBOXYLIC ACID CYCLE OF PSEUDOMONAS AERUGINOSA

1956 ◽  
Vol 2 (4) ◽  
pp. 433-440 ◽  
Author(s):  
Jack J. R. Campbell ◽  
Roberts A. Smith
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Malic Acid ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
The Other ◽  
Acid Cycle ◽  
High Ph ◽  
Optimum Activity ◽  
Fresh Cell ◽  
Cell Extracts

It was demonstrated that Pseudomonas aeruginosa possesses all the enzymes necessary for the oxidation of pyruvate to CO2 and water without passing through the conventional intermediates oxalosuccinate and α-ketoglutarate. These intermediates are bypassed by the action of the enzyme isocitratase which splits d-isocitrate to succinate plus glyoxylate. This reaction was shown to be readily reversible. The malic acid dehydrogenase content was low and in addition this enzyme required a high pH for optimum activity. In fresh cell extracts at pH 7.4 its activity was only 10% that of the other enzymes of the cycle. The malic and isocitric dehydrogenases were TPN specific. The organism was also shown to possess all the enzymes necessary for the operation of the conventional tricarboxylic acid cycle.

Two separate regions of the extrachromosomal ribosomal deoxyribonucleic acid of Tetrahymena thermophila enable autonomous replication of plasmids in Saccharomyces cerevisiae

1981 ◽  
Vol 1 (6) ◽  
pp. 535-543
Author(s):  
G B Kiss ◽  
A A Amin ◽  
R E Pearlman
Keyword(s):  
Saccharomyces Cerevisiae ◽  
High Frequency ◽  
Deoxyribonucleic Acid ◽  
Tetrahymena Thermophila ◽  
The Other ◽  
Yeast Cells ◽  
Origin Of Replication ◽  
Autonomous Replication ◽  
Coding Regions ◽  
Dna Fragment

Plasmids containing the nontranscribed central and terminal, but not the coding, regions of the extrachromosomal ribosomal deoxyribonucleic acid (rDNA) of Tetrahymena thermophila are capable of autonomous replication in Saccharomyces cerevisiae. These plasmids transform S. cerevisiae at high frequency; transformants are unstable in the absence of selection, and plasmids identical to those used for transformation were isolated from the transformed yeast cells. One plasmid contains a 1.85-kilobase Tetrahymena DNA fragment which includes the origin of bidirectional replication of the extrachromosomal rDNA. The other region of Tetrahymena rDNA allowing autonomous replication of plasmids in S. cerevisiae is a 650-base pair, adenine plus thymine-rich segment from the rDNA terminus. Neither of these Tetrahymena fragments shares obvious sequence homology with the origin of replication of the S. cerevisiae 2-microns circle plasmid or with ars1, an S. cerevisiae chromosomal replicator.

Anticandidal activity of Pseudomonas aeruginosa strains isolated from clinical specimens

Mycoses ◽  
2007 ◽  
Vol 50 (1) ◽  
pp. 74-78 ◽  
Author(s):  
Ilknur Kaleli ◽  
Nural Cevahir ◽  
Melek Demir ◽  
Umut Yildirim ◽  
Rasim Sahin
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Clinical Specimens ◽  
Anticandidal Activity
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