Recently, Dr. David Cummings, professor of biology, has been making quite a bit of news for his discovery of antibiotic-resistant bacterial DNA in Southern California wetlands. (See stories in the San Diego Union-Tribune and the Huffington Post.)
He and his students make trips to the Tijuana River Estuary, Famosa Slough in Point Loma, and Ballona Creek Estuary near the Los Angeles International Airport. The team gathers samples of sediment at low tide, mixes and freezes the samples, and then separates the DNA to find important DNA sequences.
Recently, one one such trip, one of Cummings’ student found CTX-M, a high-level drug resistance gene found in some bacteria. The discovery was crucial because it had never been seen outside a hospital setting. Since CTX-M makes bacteria resistant to antibiotics like penicillin, it’s dangerous DNA.