Mycobacterial biofilms: a greasy way to hold it together

Microorganisms growing on surfaces can form biofilms under certain conditions. In this issue of Cell, Ojha et al. (2005) investigate biofilm formation in mycobacteria. They identify new cell-wall components that are required for the formation of architecturally complex mature biofilms in these bacteria and the surprising involvement of a chaperone protein in this process.