Strain differentiation of airborne opportunistic microorganisms within a municipal landfill area as assessed by PCR MP method

A municipal landfill is the site where occurs differentiation of microorganisms inclusive of several hazardous to human health. The aim of this study was to evaluate by a PCR melting profile (PCR MP) technique the level of genetic intraspecies relatedness of strains, representing several opportunistic bacteria and fungi commonly found in bioaerosol in the landfill site. In total, 27 strains representing four bacterial species (i.e. Escherichia coli, Proteus mirabilis, Staphylococcus sciurii, S. xylosus) and 36 fungal strains belonging to Aspergillus fumigatus and A. flavus were isolated from air samples collected by an Anderson impactor within the landfill area. The PCR melting profile approach clearly indicated that except E. coli, represented by one genotype, other microbial species underwent significant genetic variability in the active sector and surrounding the landfill forest and field areas. Although the genetic relatedness of some strains could testify to distribution of microbes from the active sector to the surroundings in the past, the bacterial and fungal isolates indicated site-specific genetic fingerprints. This is the first report on the distribution of airborne opportunistic microbial species within the landfill area, performing a comparison of their genotypes and evaluation of genetic relatedness between the isolates using the PCR MP method.