Cover photograph (Copyright © 2005, American Society for Microbiology. All Rights Reserved.): Long-cell-chain phenotype of a Streptococcus thermophilus mutant strain deleted for cse. The cse gene is a functional chimeric gene, probably generated by module shuffling. It encodes an extracellular protein involved in cell separation. The picture was taken at a magnification of x100, using a condenser turret at position Ph4 on a light microscope. (See related article on page 2737.)