Identifying the sources of biosolid derived pathogen indicator organisms in aerosols by ribosomal DNA fingerprinting

Abstract

The application of the ribosomal DNA (rDNA) fingerprinting method to identify the sources of aerosolized clostridia isolates at a commercial biosolid land application site is being reported. Clostridia isolates were initially isolated from aerosol samples as well as from biosolid piles on the ground. Oligonucleotide primers, specific to the bacterial 16S‐23S interspacer region were employed in gene amplification reactions to amplify the region. For those isolates that generated similar sized amplification products, the products were digested with the HindIII restriction endonuclease to determine genetic differences. Using this approach, it was possible to genetically link some of the aerosol isolates to the biosolid piles. The results suggest that for tracking the sources of aerosolized clostridia, it would be necessary to amplify the 16S‐23S region, and if necessary, followed by restriction enzyme analyses of the product. The region, and if necessary, followed by restriction enzyme analyses of the product. The need for restriction enzyme analyses would be necessary only if the isolates in question had amplification products of similar sizes.

Key words:

• Clostridia
• gene amplification
• ribotyping
• biosolids
• aerosols

Notes

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