Polymerase chain reaction (PCR) amplification of 16S rDNA (464 bp) of typical bacterial colonies primarily cultivated on tellurite-cefixime-sorbitol MacConkey (TC-SMAC) and purified on Levine’s eosin-methylene blue (L-EMB) agar media. (a) Typical colonies identified as Escherichia coli and agglutinated with anti-O157 latex test. (b) Non E. coli colonies that showed similar morphological characteristic on TC-SMAC and purified L-EMB agar media. Positive and negative controls were included. The PCR products were subjected for electrophoresis in 2% agarose gel incorporated with gel red stain; the identification was based on sequencing of the purified PCR bands and BLAST search.