Reduction of polysaccharide production in Pseudomonas aeruginosa biofilms by bismuth dimercaprol (BisBAL) treatment.

Microorganisms in biofilms, cells attached to a surface and embedded in secreted insoluble extracellular polymers, are recalcitrant to chemical biocides and antibiotics. When Pseudomonas aeruginosa ERC1 biofilms were treated continuously with 1 x MIC of bismuth dimercaprol (BisBAL), biofilm density determined by both total cell counts and viable cell counts increased during the first 30 h period then decreased thereafter. After 120 h of treatment there was an approximate 3-log reduction in viable cell areal density compared with the untreated control. Per-cell total polysaccharide production was significantly reduced in biofilms exposed to 12.5 microM BisBAL compared with the untreated control. In biofilm cultures, 1 x MIC of BisBAL did not initially kill attached cells but was enough to reduce polysaccharide production. As treatment proceeded, the normalized polysaccharide content was reduced and those cells attached became susceptible to 1 x MIC of BisBAL.

[1]  M. R. Brown,et al.  Sensitivity of biofilms to antimicrobial agents. , 1993, The Journal of applied bacteriology.

[2]  W. G. Characklis,et al.  Observations of binary population biofilms , 1991, Biotechnology and bioengineering.

[3]  P. Stewart,et al.  Transport limitation of chlorine disinfection of Pseudomonas aeruginosa entrapped in alginate beads , 2000, Biotechnology and bioengineering.

[4]  D. Allison,et al.  Resistance of bacterial biofilms to antibiotics: a growth-rate related effect? , 1988, The Journal of antimicrobial chemotherapy.

[5]  P. Stewart,et al.  Nonuniform spatial patterns of respiratory activity within biofilms during disinfection , 1995, Applied and environmental microbiology.

[6]  P. Stewart,et al.  Chlorine Penetration into Artificial Biofilm Is Limited by a Reaction−Diffusion Interaction , 1996 .

[7]  P. Domenico,et al.  Resistance to bismuth among gram-negative bacteria is dependent upon iron and its uptake. , 1996, The Journal of antimicrobial chemotherapy.

[8]  M. V. van Loosdrecht,et al.  Heterogeneity of biofilms in rotating annular reactors: Occurrence, structure, and consequences , 1994, Biotechnology and bioengineering.

[9]  P. Stewart,et al.  Theoretical aspects of antibiotic diffusion into microbial biofilms , 1996, Antimicrobial agents and chemotherapy.

[10]  P. Domenico,et al.  Reduction of capsular polysaccharide and potentiation of aminoglycoside inhibition in gram-negative bacteria by bismuth subsalicylate. , 1991, The Journal of antimicrobial chemotherapy.

[11]  A. Chakrabarty,et al.  Exopolysaccharide production in biofilms: substratum activation of alginate gene expression by Pseudomonas aeruginosa , 1993, Applied and environmental microbiology.

[12]  J. Costerton,et al.  Bacterial biofilms in nature and disease. , 1987, Annual review of microbiology.

[13]  B A Cunha,et al.  Enhancement of bismuth antibacterial activity with lipophilic thiol chelators , 1997, Antimicrobial agents and chemotherapy.

[14]  A. Chakrabarty,et al.  Role of alginate lyase in cell detachment of Pseudomonas aeruginosa , 1994, Applied and environmental microbiology.

[15]  G. Junter,et al.  The role of oxygen limitation in the resistance of agar-entrapped, sessile-like Escherichia coli to aminoglycoside and beta-lactam antibiotics. , 1995, The Journal of antimicrobial chemotherapy.

[16]  F. Smith,et al.  COLORIMETRIC METHOD FOR DETER-MINATION OF SUGAR AND RELATED SUBSTANCE , 1956 .

[17]  P. Domenico,et al.  Bismuth‐Dimercaprol Exposes Surface Components of Klebsiella pneumoniae Camouflaged by the Polysaccharide Capsule , 1996, Annals of the New York Academy of Sciences.

[18]  A K Camper,et al.  Bacteria associated with granular activated carbon particles in drinking water , 1986, Applied and environmental microbiology.