Reviewed, UniProtKB/Swiss-Prot A3N1B4 (LEXA_ACTP2)

Names and origin

Protein names

Recommended name:
    LexA repressor
    EC=3.4.21.88

Gene names

Name:	lexA
Ordered Locus Names:	APL_1108

Organism

Actinobacillus pleuropneumoniae serotype 5b (strain L20) [Complete proteome] [HAMAP]

Taxonomic identifier

416269 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Pasteurellales › Pasteurellaceae › Actinobacillus

Protein attributes

Sequence length	210 AA.
Sequence status	Complete.
Protein existence	Inferred from homology.

General annotation (Comments)

Function	Represses a number of genes involved in the response to DNA damage (SOS response), including recA and lexA. In the presence of single-stranded DNA, recA interacts with lexA causing an autocatalytic cleavage which disrupts the DNA-binding part of lexA, leading to derepression of the SOS regulon and eventually DNA repair By similarity. HAMAP MF_00015
Catalytic activity	Hydrolysis of Ala-|-Gly bond in repressor lexA. HAMAP MF_00015
Subunit structure	Homodimer By similarity. HAMAP MF_00015
Sequence similarities	Belongs to the peptidase S24 family.

Ontologies

Keywords
Biological process	DNA damage DNA repair DNA replication SOS response Transcription Transcription regulation
Ligand	DNA-binding
Molecular function	Hydrolase Repressor
PTM	Autocatalytic cleavage
Technical term	Complete proteome
Gene Ontology (GO)
Biological process	DNA repair Inferred from electronic annotation. Source: HAMAP DNA replication Inferred from electronic annotation. Source: HAMAP SOS response Inferred from electronic annotation. Source: HAMAP negative regulation of transcription, DNA-dependent Inferred from electronic annotation. Source: HAMAP proteolysis Inferred from electronic annotation. Source: InterPro transcription Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	DNA binding Inferred from electronic annotation. Source: HAMAP serine-type endopeptidase activity Inferred from electronic annotation. Source: HAMAP
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 210	210	LexA repressor HAMAP MF_00015		PRO_1000001252
Regions
	DNA binding	30 – 50	21	H-T-H motif By similarity
Sites
	Active site	127	1	For autocatalytic cleavage activity By similarity
	Active site	164	1	For autocatalytic cleavage activity By similarity
	Site	92 – 93	2	Cleavage; by autolysis By similarity

Sequences

	Sequence		Length	Mass (Da)
	A3N1B4-1 [UniParc]. Last modified April 3, 2007. Version 1. Checksum: C7C53005A658006E	FASTA	210	23,369
	10 20 30 40 50 60 MSRKHLTARQ QEIFDFVKHH IETTGMPPTR VEIAREIGFK SPNAAEEHLK ALARKGYIEM 70 80 90 100 110 120 LSGTSRGIRI LVDNEETAAN DDGLPLIGKV AAGTPIMAIE HVESHYPVNG AMFNPNADYL 130 140 150 160 170 180 LKVNGNSMEK IGILDGDLLA VHKTNFARNG QVVVARVDDE VTVKRLEKKG DLIYLHPEND 190 200 210 ELQPIIVDPR IEYIEIEGIA VGVIRNNAWM

References

[1]	"The complete genome sequence of Actinobacillus pleuropneumoniae L20 (serotype 5b)." Foote S.J., Bosse J.T., Bouevitch A.B., Langford P.R., Young N.M., Nash J.H.E. J. Bacteriol. 190:1495-1496(2008) [PubMed: 18065534] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].

Cross-references

Sequence databases
EMBL GenBank DDBJ	CP000569 Genomic DNA. Translation: ABN74200.1.
RefSeq	YP_001053805.1.
3D structure databases
SMR	A3N1B4. Positions 4-206.
ModBase	Search...
Protein-protein interaction databases
STRING	A3N1B4.
Protein family/group databases
MEROPS	S24.001.
Genome annotation databases
GeneID	4849212.
GenomeReviews	Gene locus APL_1108 in contig CP000569_GR.
KEGG	apl:APL_1108.
Organism-specific databases
CMR	Search...
Phylogenomic databases
eggNOG	COG1974.
HOGENOM	HBG679610.
OMA	KVIGVFR.
PhylomeDB	A3N1B4.
Family and domain databases
HAMAP	MF_00015. LexA. [Tree]
InterPro	IPR006199. LexA_DNA-bd_dom. IPR006200. Pept_S24_LexA. IPR006197. Peptidase_S24_LexA_cons-reg. IPR019759. Peptidase_S24_S26_cons-reg. IPR015927. Peptidase_S24_S26A/B/C. IPR011056. Peptidase_S24_S26A/B/C_b-rbn. IPR011991. WHTH_trsnscrt_rep_DNA-bd. [Graphical view]
Gene3D	G3DSA:2.10.109.10. Pept_S24_S26_C. 1 hit. G3DSA:1.10.10.10. Wing_hlx_DNA_bd. 1 hit.
Pfam	PF01726. LexA_DNA_bind. 1 hit. PF00717. Peptidase_S24. 1 hit. [Graphical view]
PRINTS	PR00726. LEXASERPTASE.
TIGRFAMs	TIGR00498. lexA. 1 hit.
ProtoNet	Search...

Entry information

Entry name

LEXA_ACTP2

Accession

Primary (citable) accession number: A3N1B4

Entry history

Integrated into UniProtKB/Swiss-Prot:	January 15, 2008
Last sequence update:	April 3, 2007
Last modified:	February 9, 2010
This is version 26 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)