A team of researchers at the University of California, Los Angeles (UCLA) has introduced a virtual Gram staining technique that could transform how microbiologists stain and classify bacteria.

The Gram’s stain doesn’t allow them to identify every specific type of bacteria, ... A listeria outbreak that has led to 26 illnesses has been connected to a cotija and queso fresco cheese.

Gram-positive bacteria are bacteria with thick cell walls. In a Gram stain test, these organisms yield a positive result. Here’s why knowing whether the result is positive or negative is important.