Reviewed, UniProtKB/Swiss-Prot Q44069 (LEXA_AERHH)

Names and origin

Protein names

Recommended name:
    LexA repressor
    EC=3.4.21.88

Gene names

Name:	lexA
Ordered Locus Names:	AHA_0183

Organism

Aeromonas hydrophila subsp. hydrophila (strain ATCC 7966 / NCIB 9240) [Complete proteome] [HAMAP]

Taxonomic identifier

380703 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Aeromonadales › Aeromonadaceae › Aeromonas

Protein attributes

Sequence length	207 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
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.
Catalytic activity	Hydrolysis of Ala-|-Gly bond in repressor lexA. HAMAP MF_00015
Subunit structure	Homodimer By similarity.
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 – 207	207	LexA repressor HAMAP MF_00015		PRO_0000169997
Regions
	DNA binding	28 – 48	21	H-T-H motif By similarity
Sites
	Active site	124	1	For autocatalytic cleavage activity By similarity
	Active site	161	1	For autocatalytic cleavage activity By similarity
	Site	89 – 90	2	Cleavage; by autolysis By similarity
Experimental info
	Sequence conflict	92	1	P → S in CAA54479. Ref.1

Sequences

	Sequence		Length	Mass (Da)
	Q44069-1 [UniParc]. Last modified March 6, 2007. Version 2. Checksum: A5C4891A9196B960	FASTA	207	22,908
	10 20 30 40 50 60 MKPLTPRQAE VLELIKANMN ETGMPPTRAE IAQKLGFKSA NAAEEHLKAL AKKGVIEIMP 70 80 90 100 110 120 GTSRGIRLLL EEEEPLEESG LPLIGKVAAG EPILAQEHIE SHYQVDPALF HPRADFLLRV 130 140 150 160 170 180 QGMSMKNIGI LDGDLLAVHK TQEVRNGQVV VARLDEDVTV KRFQRKGSQV WLLPENEELS 190 200 PIEVDLSCQQ LTIEGLAVGV IRNADWM

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Cloning, sequence and regulation of expression of the lexA gene of Aeromonas hydrophila." Riera J., Barbe J. Gene 154:71-75(1995) [PubMed: 7867953] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Genome sequence of Aeromonas hydrophila ATCC 7966T: jack of all trades." Seshadri R., Joseph S.W., Chopra A.K., Sha J., Shaw J., Graf J., Haft D.H., Wu M., Ren Q., Rosovitz M.J., Madupu R., Tallon L., Kim M., Jin S., Vuong H., Stine O.C., Ali A., Horneman A.J., Heidelberg J.F. J. Bacteriol. 188:8272-8282(2006) [PubMed: 16980456] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].

Cross-references

Sequence databases
EMBLGenBankDDBJ	X77263 Genomic DNA. Translation: CAA54479.1. CP000462 Genomic DNA. Translation: ABK36241.1.
PIR	JC4042.
RefSeq	YP_854716.1.
3D structure databases
HSSP	HSSP built from PDB template 1JHH based on UniProtKB P03033.
SMR	Q44069. Positions 2-203.
ModBase	Search...
Protein family/group databases
MEROPS	S24.001.
Genome annotation databases
GeneID	4486813.
GenomeReviews	Gene locus AHA_0183 in contig CP000462_GR.
KEGG	aha:AHA_0183.
TIGR	AHA_0183.
Phylogenomic databases
OMA	Q44069. KVIGVFR.
Family and domain databases
HAMAP	MF_00015. [Tree]
InterPro	IPR006199. LexA_DNA_bd. IPR006200. Pept_S24_LexA. IPR006197. Peptidase_S24_LexA_cons-reg. IPR019759. Peptidase_S24_S26_cons-reg. IPR011056. Peptidase_S24_S26A/B/C_b-rbn. IPR011991. Wing_hlx_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_AERHH

Accession

Primary (citable) accession number: Q44069
Secondary accession number(s): A0KEQ1

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 1, 1997
Last sequence update:	March 6, 2007
Last modified:	June 16, 2009
This is version 59 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

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