Reviewed, UniProtKB/Swiss-Prot Q9LAI0 (T2BLB_BACSQ)

Names and origin

Protein names

Recommended name:
    Type-2 restriction enzyme BslI subunit beta
      Short name=R.BslIbeta
    EC=3.1.21.4
Alternative name(s):
    Type II restriction enzyme BslI subunit beta
    Type IIT restriction enzyme BslI subunit beta
    Endonuclease BslI subunit beta

Gene names

Name:

bslIRbeta

Organism

Bacillus sp. (strain NEB-606)

Taxonomic identifier

114630 [NCBI]

Taxonomic lineage

Bacteria › Firmicutes › Bacillales › Bacillaceae › Bacillus

Protein attributes

Sequence length	301 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Recognizes the double-stranded sequence 5'-CCN7GG-3' and cleaves after N-7.
Catalytic activity	Endonucleolytic cleavage of DNA to give specific double-stranded fragments with terminal 5'-phosphates.
Cofactor	Binds 1 zinc ion per subunit.
Subunit structure	Heterotetramer of two alpha and two beta subunits. The alpha subunit is believed to be responsible for DNA recognition, while the beta subunit is thought to mediate cleavage.
Biotechnological use	Could be used to screen carcinogenic mutations in a restriction endonuclease-mediated selective PCR (or REMS-PCR) assay. In particular, could be used to detect the vast majority of mutations that occur at codons 12 or 13 of the Ras oncogenes that encode glycine (codons GGN) at those positions.
Biophysicochemical properties	Temperature dependence: Is one of the thermostable restriction enzymes that remain active after 20 to 30 cycles of thermal PCR cycling.

Ontologies

Keywords
Biological process	Restriction system
Domain	Zinc-finger
Ligand	Metal-binding Zinc
Molecular function	Endonuclease Hydrolase Nuclease
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	DNA restriction-modification system Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	Type II site-specific deoxyribonuclease activity Inferred from electronic annotation. Source: EC zinc ion binding Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 301	301	Type-2 restriction enzyme BslI subunit beta		PRO_0000077284
Regions
	Zinc finger	62 – 82	21	CHC2-type
Experimental info
	Mutagenesis	62	1	C → K: Loss of activity. Ref.2
	Mutagenesis	66	1	H → K: 50% of wild-type activity. Ref.2
	Mutagenesis	79	1	C → K: 10% of wild-type activity. Ref.2
	Mutagenesis	82	1	C → K: 10% of wild-type activity. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	Q9LAI0-1 [UniParc]. Last modified October 1, 2000. Version 1. Checksum: 9EFAD4778F5E5A4C	FASTA	301	35,272
	10 20 30 40 50 60 MEQQKFPNPR IFEDIDATDF SKHNKKHVTE DFVAENFKDV GWRVYRPFND TGIDLIAKKF 70 80 90 100 110 120 VCPDGHTKWN QNLTKEMTCS ECGKSLIEIT RFIQVKTREV KQVKTREAKG EKFFFGYTLK 130 140 150 160 170 180 SKDFRTDPRH VFLLYSDFTM DFIILPMYDY LNLFYTNQSL GSTHFSTPSF RQGNNKLNGL 190 200 210 220 230 240 SKDKNDNWVW SGVSFNEFVN EKGMDKLSCP IYDIELESYT KKIQELKFSL FYRYSPGRKN 250 260 270 280 290 300 QVSAPTVEFI NNHFSIFISL PKEAIASKRK AHLESLRQDL PEDLKKSVNE GYLVKFKGVD L

References

[1]	"Cloning, expression, and purification of a thermostable nonhomodimeric restriction enzyme, BslI." Hsieh P.-C., Xiao J.-P., O'Loane D., Xu S.-Y. J. Bacteriol. 182:949-955(2000) [PubMed: 10648519] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF N-TERMINUS, CHARACTERIZATION.
[2]	"Glucocorticoid receptor-like Zn(Cys)4 motifs in BslI restriction endonuclease." Scheuring Vanamee E., Hsieh P.-C., Zhu Z., Yates D., Garman E., Xu S.-Y., Aggarwal A.K. J. Mol. Biol. 334:595-603(2003) [PubMed: 14623197] [Abstract] Cited for: ZINC-BINDING, ABSORPTION SPECTROSCOPY, MUTAGENESIS OF CYS-62; HIS-66; CYS-79 AND CYS-82. Strain: NEB-606.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF135191 Genomic DNA. Translation: AAF32531.1.
3D structure databases
ModBase	Search...
Protein family/group databases
REBASE	386. BslI.
Family and domain databases
ProtoNet	Search...

Entry information

Entry name

T2BLB_BACSQ

Accession

Primary (citable) accession number: Q9LAI0

Entry history

Integrated into UniProtKB/Swiss-Prot:	February 16, 2004
Last sequence update:	October 1, 2000
Last modified:	November 4, 2008
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)