Figure 2. Isolation and Detection of Bacterial Genomic DNA from a 1 mL Urine Sample. Bacterial genomic DNA was isolated from a 1 mL urine sample from a healthy individual using Norgen's Urine DNA Isolation Kit for Exfoliated Cells or Bacteria. The provided protocol was followed, and the purified urinary bacterial DNA was eluted in 100 µL of Elution Buffer. Five microliters of the eluted DNA was then used as a template in a quantitative PCR reaction to detect the bacteria using the iQ SYBR Green Supermix (BioRad, #170-8882). Healthy humans generally have <10, 000 CFU per mL of urine, and this kit is sensitive enough to isolate genomic DNA from this small amount of bacteria (blue line in graph above). The red lines in the above graph correspond to DNA standards.

Figure 3. Isolation of Genomic DNA from both Gram-Positive and Gram-Negative Urine Bacteria. Norgen's Urine DNA Isolation Kit for Exfoliated Cells or Bacteria was used to isolate genomic DNA from 1mL urine samples spiked with the Gram-positive bacteria B. cereus (1 million cells/mL) (Lanes 1 and 2), and the Gram-negative bacteria E. coli (1 million cells/mL) (Lanes 3 and 4). The provided protocol was followed, and the bacterial DNA was eluted in 100 µL of Elution Buffer. One tenth from each elution was loaded on 1.2% agarose gel. Lane M is Norgen’s MidRanger 1kb DNA Ladder. As it can be seen, genomic DNA could be successfully isolated from both Gram positive and Gram negative bacteria.