Reviewed, UniProtKB/Swiss-Prot B3DQB4 (LEXA_BIFLD)

Names and origin

Protein names

Recommended name:
    LexA repressor
    EC=3.4.21.88

Gene names

Name:	lexA
Ordered Locus Names:	BLD_0167

Organism

Bifidobacterium longum (strain DJO10A) [Complete proteome] [HAMAP]

Taxonomic identifier

205913 [NCBI]

Taxonomic lineage

Bacteria › Actinobacteria › Actinobacteridae › Bifidobacteriales › Bifidobacteriaceae › Bifidobacterium

Protein attributes

Sequence length	241 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 – 241	241	LexA repressor HAMAP MF_00015		PRO_1000089547
Regions
	DNA binding	41 – 61	21	H-T-H motif By similarity
Sites
	Active site	165	1	For autocatalytic cleavage activity By similarity
	Active site	202	1	For autocatalytic cleavage activity By similarity
	Site	130 – 131	2	Cleavage; by autolysis By similarity

Sequences

	Sequence		Length	Mass (Da)
	B3DQB4-1 [UniParc]. Last modified July 22, 2008. Version 1. Checksum: E8A4C6300737A9D3	FASTA	241	26,049
	10 20 30 40 50 60 MSTIPFSPKQ KPDESTLTDR QRKVLDAIRT HIDEQGFAPS FREIGNAAGL KSPSSVKHQL 70 80 90 100 110 120 QVLEDKGFIR MNANKGRAIE VVAGSAPNAE KPSQASEEAT STSNVAEIYQ FPAEAIAESH 130 140 150 160 170 180 DVPLVGRIAA GVPITAEQHV DDVMRLPERL TGSGTLFMLE VHGDSMVDAA ICDGDYVVVR 190 200 210 220 230 240 EQNSAVNGDI VAALLDDEAT VKTFRKENGH VWLMPHNPAY SPIDGTHATI MGKVVTVLRK L

References

[1]

"Comparative genomic analysis of the gut bacterium Bifidobacterium longum reveals loci susceptible to deletion during pure culture growth." Lee J.H., Karamychev V.N., Kozyavkin S.A., Mills D., Pavlov A.R., Pavlova N.V., Polouchine N.N., Richardson P.M., Shakhova V.V., Slesarev A.I., Weimer B., O'Sullivan D.J. BMC Genomics 9:247-247(2008) [PubMed: 18505588] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].

Cross-references

Sequence databases
EMBLGenBankDDBJ	CP000605 Genomic DNA. Translation: ACD97613.1.
RefSeq	YP_001954111.1.
3D structure databases
ModBase	Search...
Protein family/group databases
MEROPS	S24.001.
Genome annotation databases
GeneID	6363049.
GenomeReviews	Gene locus BLD_0167 in contig CP000605_GR.
KEGG	blj:BLD_0167.
Organism-specific databases
CMR	Search...
Phylogenomic databases
OMA	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_BIFLD

Accession

Primary (citable) accession number: B3DQB4

Entry history

Integrated into UniProtKB/Swiss-Prot:	March 24, 2009
Last sequence update:	July 22, 2008
Last modified:	November 3, 2009
This is version 14 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)