mSphere of Influence: The discovery of a missing link in bacterial cell envelope biogenesis.

Gregory Harrison is a bacteriologist researching essential pathways in bacteria as potential therapeutic targets. In this mSphere of Influence article, he reflects on a series of studies that employ complementary genetic approaches to define the crucial role of AsmA-family proteins in transporting phospholipids between the inner and outer membranes of Gram-negative bacteria. The authors of these three studies identify this family of lipid transporters through the means of bacterial genetics, answering a long-standing question in bacterial physiology, and serving as a reminder that a well-designed genetic strategy can go a long way in uncovering new biology.