Comparative Investigation of the Composition and Structure of Microbial Biofilms Retrieved at Meat-Processing Plants Using Different Raw Materials

Localization and structural organization of microbial biofilms developing in anthropogenic ecological niches of meat-processing plants using different raw materials (poultry, pork, or mixed materials) were investigated. Mature biofilms were revealed both at the sites subject to routine sanitary control (equipment, sewage traps, and walls) and at other locations (ceilings, reverse (lower) side of bridges, vehicle wheels, and tunnel walls at subzero temperatures), indicating high adaptability of microbial communities. This finding indicates the urgency of modification (extension) of the list of cleansing sites and of the relevant protocols. The information on the composition and diversity of microbial biofilms in this ecotope, as well as on the physiological state of component microorganisms (e.g., active, dormant, and lysing cells) was obtained using transmission electron microscopy. The morphotypes facilitating bacterial survival in these biofilms were described (old cells and several types of specialized dormant forms).