Nathanon Trachoo and Joseph F. Frank

pp. 1243 - 1252

Abstract

The biofilm microflora isolated from a chicken house (Y1 and W1) and a meat plant (Pseudomonas
sp.) enhanced survival of C. jejuni in a low nutrient environment. We employed direct microscopic observation techniques to accomplish this objective. Staining with cyanoditolyltetrazolium chloride CTC) indicated
reduced oxygen tension in the biofilm environment, which could enhance the survival of C. jejuni. W1 biofilms with more CTC staining showed greater enhancement of C. jejuni survival than did Pseudomonas sp
biofilm with more area coverage. This may indicate that reduced oxygen in biofilm of W1 plays important
role in enhanced survival of C. jejuni. The Pseudomonas sp. biofilm exhibited the most extensive surface
coverage and was thinner (approximately 1 µm) than Y1 and W1 biofilms. Reconstructed three-dimensional
photomicrographs showed only one layer of cells in Pseudomonas sp. biofilm, while biofilms of W1 and Y1
were more complex. They consisted of different sizes of microcolonies with different thickness and void
spaces in between. These morphological and physiological properties of the biofilms may be associated with
increased survival of C. jejuni by providing improved nutrient entrapment and environmental stress
protection, but no characteristic by itself could explain enhanced survival, which appears to be a complex
phenomenon.