Bacteria's bodies are well-organized.

The insides of bacteria are far more organized than scientists ever had suspected, a team of Stanford University Medical Center researchers - Lucy Shapiro, chair of the School of Medicine's Department of Developmental Biology, and postdoctoral researchers Janine Maddock and Dickon Alley - has discovered. This group's finding debunks the commonly held belief - taught to biology students from grade school on - that bacteria are tiny bags of largely disorganized protoplasm. It was believed that their tiny size precluded any need for localized protein complexes.

"Bacteria are very little. It's always been assumed that they can carry out their business based on diffusion of molecules through the cell. Because bacteria are so little, a molecule that enters at one place can almost immediately find itself all the way across the cell. Unlike cells in higher organisms, bacteria don't have complex train tracks (something called the cytoskeleton) to get molecules around the cell," Shapiro notes.

However, Maddock and Shapiro have found that bacteria do have precisely placed protein complexes that carry out cellular functions. They demonstrate that, in Escherichia coli, proteins involved in directing the movement of bacteria in response to foods or poisons are clustered at the cell poles. In a sense, these protein clusters can be viewed as E. coli's nose.

This discovery adds to a growing body of evidence that the proteins making up bacteria are organized according to their functions. A few years ago, scientists began turning up results indicating that proteins involved in cell division band together to form a structure around the waist of the cell...