Shewanella putrefaciens Adhesion and Biofilm Formation on Food Processing Surfaces

Abstract

Laboratory model systems were developed for studying Shewanella putrefaciens adhesion and biofilm formation under batch and flow conditions. S. putrefaciens plays a major role in food spoilage and may cause microbially induced corrosion on steel surfaces. S. putrefaciens bacteria suspended in buffer adhered readily to stainless steel surfaces. Maximum numbers of adherent bacteria per square centimeter were reached in 8 h at 25°C and reflected the cell density in suspension. Numbers of adhering bacteria from a suspension containing 10 8 CFU/ml were much lower in a laminar flow system (modified Robbins device) (reaching 10 2 CFU/cm 2 ) than in a batch system (reaching 10 7 CFU/cm 2 ), and maximum numbers were reached after 24 h. When nutrients were supplied, S. putrefaciens grew in biofilms with layers of bacteria. The rate of biofilm formation and the thickness of the film were not dependent on the availability of carbohydrate (lactate or glucose) or on iron starvation. The number of S. putrefaciens bacteria on the surface was partly influenced by the presence of other bacteria (Pseudomonas fluorescens) which reduced the numbers of S. putrefaciens bacteria in the biofilm. Numbers of bacteria on the surface must be quantified to evaluate the influence of environmental factors on adhesion and biofilm formation. We used a combination of fluorescence microscopy (4,6-diamidino-2-phenylindole staining and in situ hybridization, for mixed-culture studies), ultrasonic removal of bacteria from surfaces, and indirect conductometry and found this combination sufficient to quantify bacteria on surfaces.

Genome sequence of the dissimilatory metal ion–reducing bacterium Shewanella oneidensis

“…Shewanella oneidensis has two type IV pilin gene clusters (MSHA and tapABCD) that may be important as host colonization factors, phage receptors, and mediators of DNA transfer. Additionally, S. oneidensis is known to attach to solid surfaces (i.e., iron and manganese oxides) and form biofilms 13,27,28 , and MSHA plays a role in biofilm formation in V. cholerae 29,30 .…”

Phage-induced lysis enhances biofilm formation in Shewanella oneidensis MR-1

“…It has been hypothesized that direct interaction of Shewanella cells with, or close proximity to, an appropriate surface facilitates the deposition of electrons (Das and Caccavo, 2000;Gorby et al, 2006;McLean et al, 2010). In fact, Shewanella species have been demonstrated to adhere to various surfaces and form biofilms (Bagge et al, 2001;Thormann et al, 2004Thormann et al, , 2005Thormann et al, , 2006Teal et al, 2006;McLean et al, 2008a;Zhang et al, 2010).…”

AggA is required for aggregation and increased biofilm formation of a hyper-aggregating mutant of Shewanella oneidensis MR-1

“…Since S. oneidensis and related Shewanella species have been isolated from corroding steel pipelines (Semple & Westlake, 1987;Dubiel et al, 2002), a mechanistic understanding of the role of Shewanella biofilm formation and metabolic activity may help to facilitate corrosion control (Lee & Newman, 2003). The capacity of S. oneidensis to attach to and detach from solid surfaces and to form biofilms has already been described in a number of applications and studies (Bagge et al, 2001;Little et al, 1998;Thormann et al, 2004Thormann et al, , 2005. It has recently been suggested that two type IV pilin gene clusters, MSHA (mannosesensitive haemagglutinin) and tapABCD, could be involved in this process (Heidelberg et al, 2002), in the same way that MSHA plays a role in biofilm formation by Vibrio cholerae (Chiavelli et al, 2001).…”