Full Name: Locus of enterocyte effacement
Location: 1~35624 bp
Size: 35 Kbp
G+C content (%): 38.36/50.8 (PAI/Genome)
EPEC O127:H6 (E2348/69) and EHEC O157:H7: selC tRNA gene
EPEC O111:H8/H- and STEC O26:H11/H-: pheU tRNA gene
STEC O103:H2: pheV tRNA gene
Inducing the attaching and effacing (A/E) histopathology.
Contain 41 ORFs, divided into three functional domains:
the middle domain contains the eae and tir genes
the second domain is located upstream of the eae/tir domain and encodes a type III secretion system
the third domain located downstream of the eae/tir domain encodes the EPEC secreted proteins (Esps).
Organized in five major operons:
LEE1 (ler, orf2 - 5, and escRSTU),
LEE2 (sepZ, rorf8, escJ, rorf6, escC, and cesD),
LEE3 (orf12, escVN, orf15, orf16, sepQ, and orf18),
LEE4 (sepL, espADB, orf27, escF, orf29, and espF),
tir (the tir operon also has been called LEE5).
Genes designated as esc (E. coli secretion) encode components of a type III secretion apparatus that are highly homologous with ysc genes of Y. pestis and are highly conserved between EPEC and EHEC.
Genes designated esp encode E. coli secreted proteins.
ces genes encode chaperones.
A stable element in the chromosome, lack of obvious IS elements or phage sequences.
Present in all EPEC strains as well as in most A/E-positive strains, including EHEC, rabbit EPEC and Citrobacter rodentium.
Not present in normal flora E. coli, UPEC, ETEC, EIEC, or EAEC.
In EPEC E2348/69 and EHEC O157:H7 the LEE is inserted at the selenocysteine (selC) tRNA locus, the same location as other PAIs in ETEC, UPEC, Shigella flexneri, and Salmonella enterica serovar Typhimurium.
Elliott SJ, et al., 1998. The complete sequence of the locus of enterocyte effacement (LEE) from enteropathogenic Escherichia coli E2348/69. Mol. Microbiol. 28(1):1-4.
McDaniel TK, Kaper JB, 1997. A cloned pathogenicity island from enteropathogenic Escherichia coli confers the attaching and effacing phenotype on E. coli K-12. Mol. Microbiol. 23(2):399-407.
Schmidt H, Hensel M, 2004. Pathogenicity islands in bacterial pathogenesis. Clin. Microbiol. Rev. 17(1):14-56.