Show simple item record

dc.contributor.authorSarkisova, S. A.
dc.contributor.authorPatrauchan, Marianna A.
dc.contributor.authorBerglund, Deborah L.
dc.contributor.authorNivens, David E.
dc.contributor.authorFranklin, Michael J.
dc.date.accessioned2017-07-19T21:11:23Z
dc.date.available2017-07-19T21:11:23Z
dc.date.issued2005-06
dc.identifier.citationSarkisova S, Patrauchan MA, Berglund D, Nivens DE, Franklin MJ, "Calcium-induced virulence factors associated with the extracellular matrix of mucoid Pseudomonas aeruginosa biofilms," J Bacteriol, 2005 187(13):4327-4337en_US
dc.identifier.issn0021-9193
dc.identifier.urihttps://scholarworks.montana.edu/xmlui/handle/1/13339
dc.description.abstractPseudomonas aeruginosa colonizes the pulmonary tissue of patientswith cystic fibrosis (CF), leading to biofilm-associated infections.The pulmonary fluid of CF patients usually contains elevated concentrations of cations and may contain the P. aeruginosa redox-active pigment pyocyanin, which is known to disrupt calcium homeostasis of host cells. Since divalent cations are important bridging ions for bacterial polysaccharides and since they may play regulatory roles in bacterial gene expression, we investigated the effect of calcium ions on the extracellular matrix constituents of P. aeruginosa biofilms. For mucoid strain P. aeruginosa FRD1,calcium addition (1.0 and 10 mM as CaCl2) resulted in biofilmsthat were at least 10-fold thicker than biofilms without added calcium. Scanning confocal laser microscopy showed increased spacing between cells for the thick biofilms, and Fourier transform infrared spectroscopy revealed that the material between cells is primarily alginate. An algD transcriptional reporter demonstrated that calcium addition caused an eightfold increase in alg gene expression in FRD1 biofilms. Calcium addition also resulted in increased amounts of three extracellular proteases (AprA, LasB, and PrpL). Immunoblots of the biofilm extracellular material established that AprA was harbored within the biofilm extracellular matrix. An aprA deletion mutation and a mutation in gene for a putative P. aeruginosa calmodulin-like protein did not significantly affect calcium-induced biofilm structure. Two-dimensional gel electrophoresis showed increased amounts of phenazine biosynthetic proteins in FRD1 biofilms and in calcium-amended planktonic cultures. Spectrochemical analyses showed that the calcium addition causes a three- to fivefold increase in pyocyanin production. These results demonstrate that calcium addition affects the structure and extracellular matrix composition of mucoid P. aeruginosa biofilms, through increased expression and stability of bacterial extracellular products. The calcium-induced extracellular matrix of mucoid P. aeruginosa consists primarily of the virulence factor alginate and also harbors extracellular proteases and perhaps pyocyanin, a biomolecule that may further disrupt cellular calcium levels.en_US
dc.titleCalcium-induced virulence factors associated with the extracellular matrix of mucoid Pseudomonas aeruginosa biofilmsen_US
dc.typeArticleen_US
mus.citation.extentfirstpage4327en_US
mus.citation.extentlastpage4337en_US
mus.citation.issue13en_US
mus.citation.journaltitleJournal of Bacteriologyen_US
mus.citation.volume187en_US
mus.identifier.categoryEngineering & Computer Scienceen_US
mus.identifier.doi10.1128/jb.187.13.4327-4337.2005en_US
mus.relation.collegeCollege of Engineeringen_US
mus.relation.departmentCenter for Biofilm Engineering.en_US
mus.relation.departmentChemical & Biological Engineering.en_US
mus.relation.departmentChemical Engineering.en_US
mus.relation.departmentMicrobiology & Immunology.en_US
mus.relation.universityMontana State University - Bozemanen_US
mus.relation.researchgroupCenter for Biofilm Engineering.en_US
mus.data.thumbpage8en_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record