Diaz, Z.Xavier, KB.Miller, ST.2010-08-122010-08-122009-08-28Diaz, Z., Xavier, KB., Miller, ST. (2009). “The crystal structure of the Escherichia coli autoinducer-2 processing protein LsrF”. PLoS Genet. 4 (8): 1-101932-6203http://hdl.handle.net/10400.7/193Many bacteria produce and respond to the quorum sensing signal autoinducer-2 (AI-2). Escherichia coli and Salmonella typhimurium are among the species with the lsr operon, an operon containing AI-2 transport and processing genes that are up regulated in response to AI-2. One of the Lsr proteins, LsrF, has been implicated in processing the phosphorylated form of AI-2. Here, we present the structure of LsrF, unliganded and in complex with two phospho-AI-2 analogues, ribose-5-phosphate and ribulose-5-phosphate. The crystal structure shows that LsrF is a decamer of (alpha beta)(8)-barrels that exhibit a previously unseen N-terminal domain swap and have high structural homology with aldolases that process phosphorylated sugars. Ligand binding sites and key catalytic residues are structurally conserved, strongly implicating LsrF as a class I aldolase.engjournal article