Detecting E.coli Strains Using Molecular Electronics

New technology developed by Josh Hihath and colleagues at UC Davis uses atomically fine electrodes to suspend a DNA probe that binds target RNA. The device is able to detect as little as a one-base change in RNA, enough to detect toxic strains of E. coli.

By Aditi Risbud Bartl

Finding a fast and inexpensive way to detect specific strains of bacteria and viruses is critical to food safety, water quality, environmental protection and human health. However, current methods for detecting illness-causing strains of bacteria such as E. coli require either time-intensive biological cell cultures or DNA amplification approaches that rely on expensive laboratory equipment.

Multi-state E. coli Outbreak Linked to Romaine Lettuce

 By Heidi Meier and Ann Filmer

The U.S. Centers for Disease Control and Prevention (CDC) released a media statement in late December profiling a multi-state outbreak of food poisoning caused by the bacteria E. coli O157:H7 with 17 reported illnesses. Romaine and leafy greens are among the suspected sources of contamination, but no definitive source or location has been confirmed at this time, according to the CDC.

A lettuce field in California (photo by Trevor Suslow, UC Davis)

Protein Synthesis Machinery from Bacterial Consortia in One Shot

By Holly Ober

A new technique developed at UC Davis may have broken the barrier to rapid assembly of pure protein synthesis machinery outside of living cells.

Colored bacteria

E. coli bacteria tagged with different colors produced different mixtures of proteins. Together, the bacterial consortium makes all the proteins needed for mRNA translation/protein synthesis (Fernando Villarreal, UC Davis)

In order to reconstitute cellular reactions outside of biological systems, scientists need to produce the proteins involved. Rapid yet high purity reconstitution of the cellular reactions is critical for the high-throughput study of cellular pathways and cell-free diagnostic tests for various diseases. Reconstituting cellular reactions outside cells, however, requires the separate expression and purification of each protein required to execute the reactions. This process is expensive and time consuming, making the production of more than several proteins at once extremely challenging.