Abstract
The molecular mechanisms underlying the spatiotemporal development and environmental resistance of biofilms and colonies remain largely unknown. We show that a biofilm yeast colony is a finely tuned, complex multicellular organism, in which specialized cells jointly execute multiple protection strategies.
These include a Pdr1p-regulated mechanism whereby multidrug-resistance transporters Pdr5p and Snq2p expel external compounds solely within the surface cell layers, as well as developmentally regulated production by internal cells of a selectively permeable extracellular matrix. The two mechanisms act in concert during colony development, allowing growth of new cell generations in a well protected, internal cavity of the colony.
Colony architecture is strengthened by intercellular fiber connections.