Ampicillin Resistant Bacteria found in Surface Water around the San Gabriel Valley.

Antibiotic resistance bacteria are strains of bacteria that evolve/develop resistance to antibiotics designed to kill them. When these strains become more widespread, bacterial infections become more difficult or impossible to treat. This study monitored the prevalence of ampicillin-resistant bacteria in the San Gabriel Valley, a highly populated, urbanized area. So, ampicillin was selected for this study because it is a widely used antibiotic. Surface water samples were collected from local waterways in the San Gabriel Valley, including rivers and lakes. Each sample was cultivated on two standard nutrient agar plates, one with ampicillin, and one without (control). Both sets of plates were incubated at a temperature of 37°C for 48 hours. Afterward, bacterial colonies were counted and compared to determine the survival rate on the ampicillin plates. Data revealed a widespread, diverse presence of ampicillin-resistant bacteria with an average of 31 colonies for each plate containing ampicillin. However, the result were very diverse, spanning from 1 colony to 79 colonies. This indicates that environmental waterways may act as reservoirs for antibiotic resistance, which can contribute to the spread of resistant bacteria and limit the future effectiveness of ampicillin and similar drugs.