Biofilm formation by saprophytic and pathogenic leptospires. Microbiology

Unité de Biologie des Spirochètes, Institut Pasteur, 75724 Paris Cedex 15, France.
Microbiology (Impact Factor: 2.56). 06/2008; 154(Pt 5):1309-17. DOI: 10.1099/mic.0.2007/014746-0
Source: PubMed


Leptospires exist as saprophytic organisms that are aquatic or as pathogens that are able to survive in water. Leptospirosis is transmitted to humans through environmental surface waters contaminated by the urine of mammals, usually rodents, which are chronically infected by pathogenic strains. The ecology of Leptospira spp. prompted us to evaluate if these spirochaetes were able to form biofilms. This study investigated the characteristics of biofilm development by both saprophytic and pathogenic Leptospira species using microscopic examinations and a polystyrene plate model. Biofilms were formed preferentially on glass and polystyrene surfaces. Electron microscopic images showed cells embedded in an extracellular matrix. The formation of such a biofilm is consistent with the life of saprophytic strains in water and may help pathogenic strains to survive in environmental habitats and to colonize the host.

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Available from: Sophie Kernéis-Golsteyn, Mar 11, 2014
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    • "Using an immunohistochemical technique, we determined that the copious non-sulfated mucopolysaccharide present is largely alginate. Bacterial alginate, an O-acetylated linear polymer of β-D-mannuronate and α-L-guluronate residues, is mainly known as a component of Pseudomonas aeruginosa [39] and Azotobacter vinelandii [40] biofilms; however, it was recently reported that Leptospira biflexa biofilm also contains alginate [35]. These microorganisms are significantly different taxonomically, yet still produce identical or nearly identical types of some extracellular compounds in their biofilms. "
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    PLoS ONE 10/2012; 7(10):e48277. DOI:10.1371/journal.pone.0048277 · 3.23 Impact Factor
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    • "These organs can offer a large lipid supply because fatty acids are an essential requirement for leptospiral growth [29] [30]. There is evidence that leptospiras form a biofilm during kidney colonization in the proximal renal tubule lumen of rabbit novergicus [31]. Leptospiras can, however, also be found in other organs such as the lung and central nervous system [29] [30] "
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    Mediators of Inflammation 10/2012; 2012(1):317950. DOI:10.1155/2012/317950 · 3.24 Impact Factor
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    • "b-Toxin also promoted biofilm formation in vivo in a rabbit model of S. aureus endocarditis (Huseby et al., 2010). Pathogenic leptospires have been shown to form biofilms in vitro (Ristow et al., 2008), and biofilm formation may be essential for long-term leptospiral survival in the renal tubules of the reservoir host. "
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