scholarly journals Identification of Pseudomonas aeruginosa glpM, whose gene product is required for efficient alginate biosynthesis from various carbon sources.

1995 ◽  
Vol 177 (16) ◽  
pp. 4801-4804 ◽  
Author(s):  
H P Schweizer ◽  
C Po ◽  
M K Bacic
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Gene Product ◽  
Carbon Sources ◽  
Alginate Biosynthesis

Application of Phenotype Microarray for Profiling Carbon Sources Utilization between Biofilm and Non-Biofilm of Pseudomonas aeruginosa from Clinical Isolates

2020 ◽  
Vol 21 (14) ◽  
pp. 1539-1550
Author(s):  
Nur S. Ismail ◽  
Suresh K. Subbiah ◽  
Niazlin M. Taib
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Carbon Sources ◽  
Anaerobic Respiration ◽  
Regulatory System ◽  
Negative Control ◽  
High Morbidity ◽  
Metabolic Profiles ◽  
Phenotype Microarray ◽  
Diverse Environment ◽  
Phenotype Microarrays

Background: This is the fastest work in obtaining the metabolic profiles of Pseudomonas aeruginosa in order to combat the infection diseases which leads to high morbidity and mortality rates. Pseudomonas aeruginosa is a high versatility of gram-negative bacteria that can undergo aerobic and anaerobic respiration. Capabilities in deploying different carbon sources, energy metabolism and regulatory system, ensure the survival of this microorganism in the diverse environment condition. Determination of differences in carbon sources utilization among biofilm and non-biofilm of Pseudomonas aeruginosa provides a platform in understanding the metabolic activity of the microorganism. Methods: The study was carried out from September 2017 to February 2019. Four archive isolates forming strong and intermediate biofilm and non-biofilms producer were subcultured from archive isolates. ATCC 27853 P. aeruginosa was used as a negative control or non-biofilm producing microorganism. Biofilm formation was confirmed by Crystal Violet Assay (CVA) and Congo Red Agar (CRA). Metabolic profiles of the biofilm and non-biofilms isolates were determined by phenotype microarrays (Biolog Omnilog). Results and Discussion: In this study, Pseudomonas aeruginosa biofilm isolates utilized uridine, L-threonine and L-serine while non-biofilm utilized adenosine, inosine, monomethyl, sorbic acid and succinamic acid. Conclusion: The outcome of this result will be used for future studies to improve detection or inhibit the growth of P. aeruginosa biofilm and non-biofilm respectively.

Cloning and genetic mapping of SNF1, a gene required for expression of glucose-repressible genes in Saccharomyces cerevisiae

1984 ◽  
Vol 4 (1) ◽  
pp. 49-53
Author(s):  
J L Celenza ◽  
M Carlson
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Genetic Mapping ◽  
Gene Product ◽  
Structural Gene ◽  
Glucose Repression ◽  
Carbon Sources ◽  
Recombinant Plasmids ◽  
The Right ◽  
Integrating Vector

A functional SNF1 gene product is required to derepress expression of many glucose-repressible genes in Saccharomyces cerevisiae. Strains carrying a snf1 mutation are unable to grow on sucrose, galactose, maltose, melibiose, or nonfermentable carbon sources; utilization of these carbon sources is regulated by glucose repression. The inability of snf1 mutants to utilize sucrose results from failure to derepress expression of the structural gene for invertase at the RNA level. We isolated recombinant plasmids carrying the SNF1 gene by complementation of the snf1 defect in S. cerevisiae. A 3.5-kilobase region is common to the DNA segments cloned in five different plasmids. Transformation of S. cerevisiae with an integrating vector carrying a segment of the cloned DNA resulted in integration of the plasmid at the SNF1 locus. This result indicates that the cloned DNA is homologous to sequences at the SNF1 locus. By mapping a plasmid marker linked to SNF1 in this transformant, we showed that the SNF1 gene is located on chromosome IV. We then mapped snf1 to a position 5.6 centimorgans distal to rna3 on the right arm; snf1 is not extremely closely linked to any previously mapped mutation.

scholarly journals Genetic Determinants Involved in the Susceptibility of Pseudomonas aeruginosa to β-Lactam Antibiotics

2010 ◽  
Vol 54 (10) ◽  
pp. 4159-4167 ◽  
Author(s):  
Carolina Alvarez-Ortega ◽  
Irith Wiegand ◽  
Jorge Olivares ◽  
Robert E. W. Hancock ◽  
José Luis Martínez
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Detailed Analysis ◽  
Barrier Function ◽  
Mechanisms Of Action ◽  
Mutant Library ◽  
Genetic Determinants ◽  
Intrinsic Resistance ◽  
Resistance Phenotype ◽  
Mixed Phenotype ◽  
Alginate Biosynthesis

ABSTRACT The resistome of P. aeruginosa for three β-lactam antibiotics, namely, ceftazidime, imipenem, and meropenem, was deciphered by screening a comprehensive PA14 mutant library for mutants with increased or reduced susceptibility to these antimicrobials. Confirmation of the phenotypes of all selected mutants was performed by Etest. Of the total of 78 confirmed mutants, 41 demonstrated a reduced susceptibility phenotype and 37 a supersusceptibility (i.e., altered intrinsic resistance) phenotype, with 6 mutants demonstrating a mixed phenotype, depending on the antibiotic. Only three mutants demonstrated reduced (PA0908) or increased (glnK and ftsK) susceptibility to all three antibiotics. Overall, the mutant profiles of susceptibility suggested distinct mechanisms of action and resistance for the three antibiotics despite their similar structures. More detailed analysis indicated important roles for novel and known β-lactamase regulatory genes, for genes with likely involvement in barrier function, and for a range of regulators of alginate biosynthesis.

scholarly journals Hierarchical management of carbon sources is regulated similarly by the CbrA/B systems in Pseudomonas aeruginosa and Pseudomonas putida

Microbiology ◽  
2014 ◽  
Vol 160 (10) ◽  
pp. 2243-2252 ◽  
Author(s):  
Martina Valentini ◽  
Sofía M. García-Mauriño ◽  
Isabel Pérez-Martínez ◽  
Eduardo Santero ◽  
Inés Canosa ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Pseudomonas Putida ◽  
Nitrogen Availability ◽  
Carbon Sources ◽  
Signal Transduction Pathway ◽  
Exact Nature ◽  
Energy Status ◽  
Regulatory Systems ◽  
Close Relationship ◽  
Carbon Nitrogen Ratio

The CbrA/B system in pseudomonads is involved in the utilization of carbon sources and carbon catabolite repression (CCR) through the activation of the small RNAs crcZ in Pseudomonas aeruginosa, and crcZ and crcY in Pseudomonas putida. Interestingly, previous works reported that the CbrA/B system activity in P. aeruginosa PAO1 and P. putida KT2442 responded differently to the presence of different carbon sources, thus raising the question of the exact nature of the signal(s) detected by CbrA. Here, we demonstrated that the CbrA/B/CrcZ(Y) signal transduction pathway is similarly activated in the two Pseudomonas species. We show that the CbrA sensor kinase is fully interchangeable between the two species and, moreover, responds similarly to the presence of different carbon sources. In addition, a metabolomics analysis supported the hypothesis that CCR responds to the internal energy status of the cell, as the internal carbon/nitrogen ratio seems to determine CCR and non-CCR conditions. The strong difference found in the 2-oxoglutarate/glutamine ratio between CCR and non-CCR conditions points to the close relationship between carbon and nitrogen availability, or the relationship between the CbrA/B and NtrB/C systems, suggesting that both regulatory systems sense the same sort or interrelated signal.

scholarly journals The nucleotide sequence of the Pseudomonas aeruginosa pyrE-crc-rph region and the purification of the crc gene product.

1996 ◽  
Vol 178 (19) ◽  
pp. 5627-5635 ◽  
Author(s):  
C H MacGregor ◽  
S K Arora ◽  
P W Hager ◽  
M B Dail ◽  
P V Phibbs
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Nucleotide Sequence ◽  
Gene Product

scholarly journals BdlA, a Chemotaxis Regulator Essential for Biofilm Dispersion in Pseudomonas aeruginosa

2006 ◽  
Vol 188 (21) ◽  
pp. 7335-7343 ◽  
Author(s):  
Ryan Morgan ◽  
Steven Kohn ◽  
Sung-Hei Hwang ◽  
Daniel J. Hassett ◽  
Karin Sauer
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Gene Product ◽  
Signaling Cascade ◽  
Environmental Cues ◽  
Environmental Sensing ◽  
Environmental Signals ◽  
Isogenic Mutant ◽  
Biofilm Detachment ◽  
Biofilm Dispersion ◽  
Do So

ABSTRACT Multiple environmental cues have been shown to trigger biofilm detachment, the transition from surface-attached, highly organized communities known as biofilms to the motile lifestyle. The goal of this study was to identify a gene product involved in sensing environmental cues that trigger biofilm dispersion in Pseudomonas aeruginosa. To do so, we focused on novel putative chemotaxis transducer proteins that could potentially be involved in environmental sensing. We identified a locus encoding such a protein that played a role in detachment, as indicated by the observation that an isogenic mutant biofilm could not disperse in response to a variety of environmental cues. The locus was termed bdlA for biofilm dispersion locus. The BdlA protein harbors an MCP (methyl-accepting chemotaxis protein) domain and two PAS (Per-Arnt-Sint) domains that have been shown to be essential for responding to environmental signals in other proteins. The dispersion-deficient phenotype of the bdlA mutant was confirmed by treatment with the biocide H2O2 and by microscopic observations. The dispersion response was independent of motility. bdlA mutant biofilms were found to have increased adherent properties and increased intracellular levels of cyclic di-GMP (c-di-GMP). Our findings suggest that BdlA may be a link between sensing environmental cues, c-di-GMP levels, and detachment. Based on our findings, a possible involvement of BdlA in a signaling cascade resulting in biofilm dispersion is discussed.

scholarly journals Identification of the PA1113 Gene Product as an ABC Transporter Involved in the Uptake of Carbenicillin in Pseudomonas aeruginosa PAO1

Antibiotics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 596
Author(s):  
Christian Hulen ◽  
Pierre-jean Racine ◽  
Sylvie Chevalier ◽  
Marc Feuilloley ◽  
Nour-Eddine LOMRI
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Gene Product ◽  
Abc Transporter ◽  
Abc Transporters ◽  
Inhibitory Effect ◽  
Eukaryotic Cells ◽  
Amino Acid Sequence Homology ◽  
Protein Targets ◽  
Bacterial Cytoplasm

The resistance of Pseudomonas aeruginosa to antibiotics is multi factorial and complex. Whereas efflux pumps such as MexAB-OprM have been thought to predominate, here we show that a novel ATP Binding Cassette (ABC) transporter that mediates influx of carbenicillin from the periplasm to the cytoplasm and away from its cell wall target plays an important role in the resistance of P. aeruginosa to this antibiotic. Treatment of P. aeruginosa with verapamil, an inhibitor of ABC transporters in eukaryotic cells, increases its sensitivity to carbenicillin. Using amino acid sequence homology with known verapamil protein targets as a probe, we determined that the PA1113 gene product, an ABC transporter, mediates carbenicillin uptake into the bacterial cytoplasm. Docking and pharmacological analyses showed that verapamil and carbenicillin compete for the same site on the PA1113 gene protein, explaining the inhibitory effect of verapamil on carbenicillin uptake, and furthermore suggest that the PA1113 ABC transporter accounts for about 30% of P. aeruginosa carbenicillin resistance. Our findings demonstrate that the PA1113 gene product helps mediate carbenicillin resistance by transporting it away from its cell wall target and represents a promising new therapeutic target.

Sign in / Sign up

Export Citation Format

Share Document