Family U49

Family

Summary Holotypes Alignment Tree Genomes Literature Architecture

Summary for family U49

Name	Peptidase family U49 (Lit protease family)
Family type peptidase	U49.001 - Lit peptidase (Escherichia coli), MEROPS Accession MER0004305 (peptidase unit: 1-297)
Content of family	Peptidase family U49 contains only the Lit peptidase from Escherischia coli.
History	Identifier created: MEROPS 5.61 (29 October 2001) Lit peptidase has been reviewed by Copeland & Kleanthous, 2004.
Catalytic type	Peptidase of unknown catalytic type
Active site	No active site residues have been identified in the Lit peptidase, although it may be significant that an HEXXH motif occurs in the sequence at residues 160 - 164 (see the Alignment).
Activities and specificities	Lit peptidase cleaves domain I of elongation factor Tu (Copeland & Kleanthous, 2004).
Inhibitors	Lit peptidase activity is not affected by the addition of zinc, and the zinc chelator 1,10-phenanthroline does not inhibit, as would have been expected for a metallopeptidase (Georgiou, 1998).
Molecular structure	Lit peptidase is a 33-kDa protein that contains two putative transmembrane domains, the second of which includes an HEXXH motif similar to the zinc-binding motif found in the metallopeptidases of clans MA and MM (Snyder, 1995). The peptidase is approximately 36% alpha helix and 31% beta-sheet (Copeland & Kleanthous, 2004).
Clan	unassigned
Basis of clan assignment	Protein fold and active site residues are not known for any members of this family.

Distribution of family	Bacteria	details
	Archaea	-
	Protozoa	-
	Fungi	-
	Plants	-
	Animals	-
	Viruses	-

Biological functions	Lit peptidase has an important role in bacterial cell death in response to infection by bacteriophage T4. Following binding of Gol peptide to domains II and III of elongation factor Tu, the protease cleaves domain I of the elongation factor. This prevents binding of guanine nucleotides, shuts down translation and leads to cell death (Copeland & Kleanthous, 2004).The Lit-mediated proteolysis of EF-Tu alone appears to be sufficient to prevent the formation of active phage particles (Yu & Snyder, 1994) and thus to prevent further transmission of the phage.
Statistics for family U49	Sequences:	10
	Identifiers:	1
	Identifiers with PDB entries:	0
Downloadable files	Sequence library (FastA format)
	Sequence alignment (FastA format)
	Phylogenetic tree (Newick format)

Other databases	INTERPRO	IPR019504
	PFAM	PF10463

Peptidases and Homologues	MEROPS ID	Structure
Lit peptidase	U49.001	-
Family U49 unassigned peptidases	unassigned	-