scholarly journals Metagenome-Derived Clones Encoding Two Novel Lactonase Family Proteins Involved in Biofilm Inhibition in Pseudomonas aeruginosa

2008 ◽  
Vol 75 (1) ◽  
pp. 224-233 ◽  
Author(s):  
C. Schipper ◽  
C. Hornung ◽  
P. Bijtenhoorn ◽  
M. Quitschau ◽  
S. Grond ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
High Performance ◽  
Homoserine Lactone ◽  
Amino Acid Sequences ◽  
Open Reading Frames ◽  
Biofilm Inhibition ◽  
Soil Dna ◽  
Isolation And Characterization ◽  
Bacterial Quorum

ABSTRACT Here we report the isolation and characterization of three metagenome-derived clones that interfere with bacterial quorum sensing and degrade N-(3-oxooctanoyl)-l-homoserine lactone (3-oxo-C8-HSL). By using a traI-lacZ gene fusion, the metagenome-derived clones were identified from a soil DNA library and analyzed. The open reading frames linked to the 3-oxo-C8-HSL-degrading activities were designated bpiB01, bpiB04, and bpiB07. While the BpiB07 protein was similar to a known lactonase, no significant similarities were observed for the BpiB01 and BpiB04 proteins or the deduced amino acid sequences. High-performance liquid chromatography-mass spectrometry analyses confirmed that the identified genes encode novel lactone-hydrolyzing enzymes. The original metagenome-derived clones were expressed in Pseudomonas aeruginosa and employed in motility and biofilm assays. All clones were able to reproducibly inhibit motility in P. aeruginosa. Furthermore, these genes clearly inhibited biofilm formation in P. aeruginosa when expressed in P. aeruginosa PAO1. Thus, this is the first study in which metagenome-derived proteins have been expressed in P. aeruginosa to successfully inhibit biofilm formation.

scholarly journals Targeting Acyl Homoserine Lactone (AHL) of Pseudomonas aeruginosa Responsible for Biofilm Formation using Plant Metabolites

2019 ◽  
Vol 13 (3) ◽  
pp. 1841-1846
Author(s):  
Sree Samanvitha K ◽  
Sanjay Kumar S ◽  
Antony V. Samrot ◽  
Raji P ◽  
Ponnaiah Paulraj ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Homoserine Lactone ◽  
Acyl Homoserine Lactone ◽  
Plant Metabolites

scholarly journals Peptide Mix from Olivancillaria hiatula Interferes with Cell-to-Cell Communication in Pseudomonas aeruginosa

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Edward Ntim Gasu ◽  
Hubert Senanu Ahor ◽  
Lawrence Sheringham Borquaye
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Cell Communication ◽  
Microtiter Plate ◽  
Antibiofilm Activity ◽  
Dependent Manner ◽  
Biofilm Inhibition ◽  
Swarming Motility

Bacteria in biofilms are encased in an extracellular polymeric matrix that limits exposure of microbial cells to lethal doses of antimicrobial agents, leading to resistance. In Pseudomonas aeruginosa, biofilm formation is regulated by cell-to-cell communication, called quorum sensing. Quorum sensing facilitates a variety of bacterial physiological functions such as swarming motility and protease, pyoverdine, and pyocyanin productions. Peptide mix from the marine mollusc, Olivancillaria hiatula, has been studied for its antibiofilm activity against Pseudomonas aeruginosa. Microscopy and microtiter plate-based assays were used to evaluate biofilm inhibitory activities. Effect of the peptide mix on quorum sensing-mediated processes was also evaluated. Peptide mix proved to be a good antibiofilm agent, requiring less than 39 μg/mL to inhibit 50% biofilm formation. Micrographs obtained confirmed biofilm inhibition at 1/2 MIC whereas 2.5 mg/mL was required to degrade preformed biofilm. There was a marked attenuation in quorum sensing-mediated phenotypes as well. At 1/2 MIC of peptide, the expression of pyocyanin, pyoverdine, and protease was inhibited by 60%, 72%, and 54%, respectively. Additionally, swarming motility was repressed by peptide in a dose-dependent manner. These results suggest that the peptide mix from Olivancillaria hiatula probably inhibits biofilm formation by interfering with cell-to-cell communication in Pseudomonas aeruginosa.

scholarly journals Quorum-Sensing Genes in Pseudomonas aeruginosa Biofilms: Their Role and Expression Patterns

2001 ◽  
Vol 67 (4) ◽  
pp. 1865-1873 ◽  
Author(s):  
Teresa R. De Kievit ◽  
Richard Gillis ◽  
Steve Marx ◽  
Chris Brown ◽  
Barbara H. Iglewski
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Biofilm Formation ◽  
Fluorescent Protein ◽  
Expression Patterns ◽  
Homoserine Lactone ◽  
Lower Percentage ◽  
Spatial Studies ◽  
Green Fluorescent ◽  
Biofilm Development

ABSTRACT Acylated homoserine lactone molecules are used by a number of gram-negative bacteria to regulate cell density-dependent gene expression by a mechanism known as quorum sensing (QS). InPseudomonas aeruginosa, QS or cell-to-cell signaling controls expression of a number of virulence factors, as well as biofilm differentiation. In this study, we investigated the role played by the las and rhl QS systems during the early stages of static biofilm formation when cells are adhering to a surface and forming microcolonies. These studies revealed a marked difference in biofilm formation between the PAO1 parent and the QS mutants when glucose, but not citrate, was used as the sole carbon source. To further elucidate the contribution of lasI andrhlI to biofilm maturation, we utilized fusions to unstable green fluorescent protein in concert with confocal microscopy to perform real-time temporal and spatial studies of these genes in a flowing environment. During the course of 8-day biofilm development,lasI expression was found to progressively decrease over time. Conversely, rhlI expression remained steady throughout biofilm development but occurred in a lower percentage of cells. Spatial analysis revealed that lasI andrhlI were maximally expressed in cells located at the substratum and that expression decreased with increasing biofilm height. Because QS was shown previously to be involved in biofilm differentiation, these findings have important implications for the design of biofilm prevention and eradication strategies.

Iron-binding compounds impair Pseudomonas aeruginosa biofilm formation, especially under anaerobic conditions

2009 ◽  
Vol 58 (6) ◽  
pp. 765-773 ◽  
Author(s):  
Che Y. O'May ◽  
Kevin Sanderson ◽  
Louise F. Roddam ◽  
Sylvia M. Kirov ◽  
David W. Reid
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Low Oxygen ◽  
Anaerobic Conditions ◽  
Chronic Infections ◽  
Strain Pao1 ◽  
Biofilm Inhibition ◽  
Oxygen Conditions ◽  
Biofilm Development ◽  
Chelating Compounds

The success of Pseudomonas aeruginosa in cystic fibrosis (CF) and other chronic infections is largely attributed to its ability to grow in antibiotic-resistant biofilm communities. This study investigated the effects of limiting iron levels as a strategy for preventing/disrupting P. aeruginosa biofilms. A range of synthetic and naturally occurring iron-chelating agents were examined. Biofilm development by P. aeruginosa strain PAO1 and CF sputum isolates from chronically infected individuals was significantly decreased by iron removal under aerobic atmospheres. CF strains formed poor biofilms under anaerobic conditions. Strain PAO1 was also tested under anaerobic conditions. Biofilm formation by this model strain was almost totally prevented by several of the chelators tested. The ability of synthetic chelators to impair biofilm formation could be reversed by iron addition to cultures, providing evidence that these effective chelating compounds functioned by directly reducing availability of iron to P. aeruginosa. In contrast, the biological chelator lactoferrin demonstrated enhanced anti-biofilm effects as iron supplementation increased. Hence biofilm inhibition by lactoferrin appeared to occur through more complex mechanisms to those of the synthetic chelators. Overall, our results demonstrate the importance of iron availability to biofilms and that iron chelators have potential as adjunct therapies for preventing biofilm development, especially under low oxygen conditions such as encountered in the chronically infected CF lung.

scholarly journals Pseudomonas aeruginosa secreted factors impair biofilm development in Candida albicans

Microbiology ◽  
2010 ◽  
Vol 156 (5) ◽  
pp. 1476-1486 ◽  
Author(s):  
Lucy J. Holcombe ◽  
Gordon McAlester ◽  
Carol A. Munro ◽  
Brice Enjalbert ◽  
Alistair J. P. Brown ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Candida Albicans ◽  
Biofilm Formation ◽  
Bacterial Species ◽  
Homoserine Lactone ◽  
Strong Increase ◽  
Opportunistic Pathogens ◽  
Secreted Factors ◽  
Expression Of Genes ◽  
Biofilm Development

Signal-mediated interactions between the human opportunistic pathogens Pseudomonas aeruginosa and Candida albicans affect virulence traits in both organisms. Phenotypic studies revealed that bacterial supernatant from four P. aeruginosa strains strongly reduced the ability of C. albicans to form biofilms on silicone. This was largely a consequence of inhibition of biofilm maturation, a phenomenon also observed with supernatant prepared from non-clinical bacterial species. The effects of supernatant on biofilm formation were not mediated via interference with the yeast–hyphal morphological switch and occurred regardless of the level of homoserine lactone (HSL) produced, indicating that the effect is HSL-independent. A transcriptome analysis to dissect the effects of the P. aeruginosa supernatants on gene expression in the early stages of C. albicans biofilm formation identified 238 genes that exhibited reproducible changes in expression in response to all four supernatants. In particular, there was a strong increase in the expression of genes related to drug or toxin efflux and a decrease in expression of genes associated with adhesion and biofilm formation. Furthermore, expression of YWP1, which encodes a protein known to inhibit biofilm formation, was significantly increased. Biofilm formation is a key aspect of C. albicans infections, therefore the capacity of P. aeruginosa to antagonize this has clear biomedical implications.

scholarly journals Pseudomonas aeruginosa Exopolysaccharide Psl Promotes Resistance to the Biofilm Inhibitor Polysorbate 80

2012 ◽  
Vol 56 (8) ◽  
pp. 4112-4122 ◽  
Author(s):  
Michael E. Zegans ◽  
Daniel Wozniak ◽  
Edward Griffin ◽  
Christine M. Toutain-Kidd ◽  
John H. Hammond ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Nonionic Surfactant ◽  
Biofilm Formation ◽  
Laboratory Strain ◽  
Polysorbate 80 ◽  
Biosynthetic Pathways ◽  
Human Tissues ◽  
Biofilm Inhibition ◽  
Content Type ◽  
Biofilm Inhibitor

ABSTRACTPolysorbate 80 (PS80) is a nonionic surfactant and detergent that inhibits biofilm formation byPseudomonas aeruginosaat concentrations as low as 0.001% and is well tolerated in human tissues. However, certain clinical and laboratory strains (PAO1) ofP. aeruginosaare able to form biofilms in the presence of PS80. To better understand this resistance, we performed transposon mutagenesis with a PS80-resistant clinical isolate, PA738. This revealed that mutation ofalgCrendered PA738 sensitive to PS80 biofilm inhibition. AlgC contributes to the biosynthesis of the exopolysaccharides Psl and alginate, as well as lipopolysaccharide and rhamnolipid. Analysis of mutations downstream of AlgC in these biosynthetic pathways established that disruption of thepsloperon was sufficient to render the PA738 and PAO1 strains sensitive to PS80-mediated biofilm inhibition. Increased levels of Psl production in the presence of arabinose in a strain with an arabinose-induciblepslpromoter were correlated with increased biofilm formation in PS80. InP. aeruginosastrains MJK8 and ZK2870, known to produce both Pel and Psl, disruption of genes in thepslbut not thepeloperon conferred susceptibility to PS80-mediated biofilm inhibition. The laboratory strain PA14 does not produce Psl and does not form biofilms in PS80. However, when PA14 was transformed with a cosmid containing thepsloperon, it formed biofilms in the presence of PS80. Taken together, these data suggest that production of the exopolysaccharide Psl byP. aeruginosapromotes resistance to the biofilm inhibitor PS80.

scholarly journals Inhibition of Quorum Sensing in Pseudomonas aeruginosa by N-Acyl Cyclopentylamides

2007 ◽  
Vol 73 (10) ◽  
pp. 3183-3188 ◽  
Author(s):  
Takenori Ishida ◽  
Tsukasa Ikeda ◽  
Noboru Takiguchi ◽  
Akio Kuroda ◽  
Hisao Ohtake ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Virulence Factors ◽  
Biofilm Formation ◽  
Homoserine Lactone ◽  
Ring Structure ◽  
Response Regulators ◽  
Maximal Inhibition ◽  
Sensing Systems ◽  
Reporter Assays

ABSTRACT N-Octanoyl cyclopentylamide (C8-CPA) was found to moderately inhibit quorum sensing in Pseudomonas aeruginosa PAO1. To obtain more powerful inhibitors, a series of structural analogs of C8-CPA were synthesized and examined for their ability to inhibit quorum sensing in P. aeruginosa PAO1. The lasB-lacZ and rhlA-lacZ reporter assays revealed that the chain length and the ring structure were critical for C8-CPA analogs to inhibit quorum sensing. N-Decanoyl cyclopentylamide (C10-CPA) was found to be the strongest inhibitor, and its concentrations required for half-maximal inhibition for lasB-lacZ and rhlA-lacZ expression were 80 and 90 μM, respectively. C10-CPA also inhibited production of virulence factors, including elastase, pyocyanin, and rhamnolipid, and biofilm formation without affecting growth of P. aeruginosa PAO1. C10-CPA inhibited induction of both lasI-lacZ by N-(3-oxododecanoyl)-l-homoserine lactone (PAI1) and rhlA-lacZ by N-butanoyl-l-homoserine lactone (PAI2) in the lasI rhlI mutant of P. aeruginosa PAO1, indicating that C10-CPA interferes with the las and rhl quorum-sensing systems via inhibiting interaction between their response regulators (LasR and RhlR) and autoinducers.

scholarly journals Isolation and Characterization of a Bacteriophage Infecting Pseudomonas Aeruginosa and Its Application as a Potential Decontaminating Agent

2021 ◽  
Author(s):  
Sonika Sharma ◽  
Sibnarayan Datta ◽  
Soumya Chatterjee ◽  
Moumita Dutta ◽  
Jhuma Samanta ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Burst Size ◽  
Gc Content ◽  
Alginate Beads ◽  
Open Reading Frames ◽  
Isolation And Characterization ◽  
The Family ◽  
Infected Cells

Abstract To treat antibiotic resistance bacteria, bacteriophage (also called 'phage') application has recently drawn considerable attention from researchers globally. Bacteria like Pseudomonas aeruginosa are known to be associated with nosocomial infections especially in patients with compromised immune systems. In the present work, phage against P. aeruginosa (named 'DRLP1') was isolated from wastewater, enriched and characterized. Morphologically DRLP1 belongs to the family Myoviridae with a high lytic ability. DRLP1 has a burst size of approximately 100 PFU/infected cells, a rapid adsorption time when supplemented with MgCl2, and has viability in a wide temperature range and pH. Genomic sequencing and bioinformatics analysis showed that the phage genome is linear double-stranded, 66,243 bp in length and have a GC content of 54.9%. the genome encodes 93 phage related ORFs open reading frames (ORFs). Phage stability in lyophilized state, adsorption study on sodium alginate beads, and in-vitro pathogen reduction assays were also investigated. Study carried out with artificially contaminated fomites suggests that this phage has the potential for application as a biological decontaminant agent against P. aeruginosa in different conditions.

scholarly journals Biofilm inhibitor taurolithocholic acid alters colony morphology, specialized metabolism, and virulence ofPseudomonas aeruginosa

2019 ◽  
Author(s):  
Alanna R. Condren ◽  
Lisa Juliane Kahl ◽  
George Kritikos ◽  
Manuel Banzhaf ◽  
Lars E. P. Dietrich ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Bacterial Community ◽  
Biofilm Formation ◽  
Colony Morphology ◽  
Biofilm Inhibition ◽  
Specialized Metabolism ◽  
Virulence Assay ◽  
Biofilm Inhibitor ◽  
Highly Virulent ◽  
Wax Moth

AbstractBiofilm inhibition by exogenous molecules has been an attractive strategy for the development of novel therapeutics. We investigated the biofilm inhibitor taurolithocholic acid (TLCA) and its effects on the specialized metabolism, virulence and biofilm formation of the clinically relevant bacteriumPseudomonas aeruginosastrain PA14. Our study shows that TLCA alters specialized metabolism, thereby affectingP. aeruginosacolony biofilm physiology. We observed an upregulation of metabolites correlated to virulence such as the siderophore pyochelin. A wax moth virulence assay confirmed that treatment with TLCA increases virulence ofP. aeruginosa. Based on our results, we believe that future endeavors to identify biofilm inhibitors must consider how a putative lead is altering the specialized metabolism of a bacterial community to prevent pathogens from entering a highly virulent state.

Sign in / Sign up

Export Citation Format

Share Document