Reviewed, UniProtKB/Swiss-Prot P08142 (ILVB_ECOLI)

Names and origin

Protein names

Recommended name:
    Acetolactate synthase isozyme 1 large subunit
      Short name=AHAS-I
    EC=2.2.1.6
Alternative name(s):
    Acetohydroxy-acid synthase I large subunit
      Short name=ALS-I

Gene names

Name:	ilvB
Ordered Locus Names:	b3671, JW3646

Organism

Escherichia coli (strain K12) [Complete proteome] [HAMAP]

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia

Protein attributes

Sequence length	562 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Catalytic activity	2 pyruvate = 2-acetolactate + CO2.
Cofactor	Binds 1 magnesium ion per subunit By similarity. Binds 1 thiamine pyrophosphate per subunit By similarity.
Pathway	Amino-acid biosynthesis; L-isoleucine biosynthesis; L-isoleucine from 2-oxobutanoate: step 1/4. Amino-acid biosynthesis; L-valine biosynthesis; L-valine from pyruvate: step 1/4.
Subunit structure	Dimer of large and small chains.
Miscellaneous	E.coli contains genes for 3 AHAS isozymes: ilvBN, ilvGM and ilvIH. Contains 1 molecule of FAD per monomer. The role of this cofactor is not clear considering that the reaction does not involve redox chemistry By similarity.
Sequence similarities	Belongs to the TPP enzyme family.

Ontologies

Keywords
Biological process	Amino-acid biosynthesis Branched-chain amino acid biosynthesis
Ligand	FAD Flavoprotein Magnesium Metal-binding Thiamine pyrophosphate
Molecular function	Transferase
Technical term	Complete proteome
Gene Ontology (GO)
Biological process	branched chain family amino acid biosynthetic process Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	FAD binding Inferred from electronic annotation. Source: InterPro acetolactate synthase activity Inferred from electronic annotation. Source: EC magnesium ion binding Inferred from electronic annotation. Source: UniProtKB-KW thiamin pyrophosphate binding Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 562	562	Acetolactate synthase isozyme 1 large subunit		PRO_0000090784
Regions
	Nucleotide binding	264 – 285	22	FAD By similarity
	Nucleotide binding	307 – 326	20	FAD By similarity
	Region	393 – 473	81	Thiamine pyrophosphate binding
Sites
	Metal binding	444	1	Magnesium By similarity
	Metal binding	471	1	Magnesium By similarity
	Binding site	60	1	Thiamine pyrophosphate By similarity
	Binding site	162	1	FAD By similarity

Sequences

	Sequence		Length	Mass (Da)
	P08142-1 [UniParc]. Last modified August 1, 1988. Version 1. Checksum: 70F8A3128031353C	FASTA	562	60,441
	10 20 30 40 50 60 MASSGTTSTR KRFTGAEFIV HFLEQQGIKI VTGIPGGSIL PVYDALSQST QIRHILARHE 70 80 90 100 110 120 QGAGFIAQGM ARTDGKPAVC MACSGPGATN LVTAIADARL DSIPLICITG QVPASMIGTD 130 140 150 160 170 180 AFQEVDTYGI SIPITKHNYL VRHIEELPQV MSDAFRIAQS GRPGPVWIDI PKDVQTAVFE 190 200 210 220 230 240 IETQPAMAEK AAAPAFSEES IRDAAAMINA AKRPVLYLGG GVINAPARVR ELAEKAQLPT 250 260 270 280 290 300 TMTLMALGML PKAHPLSLGM LGMHGVRSTN YILQEADLLI VLGARFDDRA IGKTEQFCPN 310 320 330 340 350 360 AKIIHVDIDR AELGKIKQPH VAIQADVDDV LAQLIPLVEA QPRAEWHQLV ADLQREFPCP 370 380 390 400 410 420 IPKACDPLSH YGLINAVAAC VDDNAIITTD VGQHQMWTAQ AYPLNRPRQW LTSGGLGTMG 430 440 450 460 470 480 FGLPAAIGAA LANPDRKVLC FSGDGSLMMN IQEMATASEN QLDVKIILMN NEALGLVHQQ 490 500 510 520 530 540 QSLFYEQGVF AATYPGKINF MQIAAGFGLE TCDLNNEADP QASLQEIINR PGPALIHVRI 550 560 DAEEKVYPMV PPGAANTEMV GE

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"The nucleotide sequence of the ilvBN operon of Escherichia coli: sequence homologies of the acetohydroxy acid synthase isozymes." Wek R.C., Hausser C.A., Hatfield G.W. Nucleic Acids Res. 13:3995-4010(1985) [PubMed: 2989782] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"The ilvB locus of Escherichia coli K-12 is an operon encoding both subunits of acetohydroxyacid synthase I." Friden P., Donegan J., Mullen J., Tsui P., Freundlich M. Nucleic Acids Res. 13:3979-3993(1985) [PubMed: 2989781] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[3]	"DNA sequence and analysis of 136 kilobases of the Escherichia coli genome: organizational symmetry around the origin of replication." Burland V.D., Plunkett G. III, Daniels D.L., Blattner F.R. Genomics 16:551-561(1993) [PubMed: 7686882] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[4]	"The complete genome sequence of Escherichia coli K-12." Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V., Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F., Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B., Shao Y. Science 277:1453-1474(1997) [PubMed: 9278503] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[5]	"Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 and W3110." Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T. Mol. Syst. Biol. 2:E1-E5(2006) [PubMed: 16738553] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.

Cross-references

Sequence databases
EMBLGenBankDDBJ	X02541 Genomic DNA. Translation: CAA26387.1. L10328 Genomic DNA. Translation: AAA62023.1. U00096 Genomic DNA. Translation: AAC76694.1. AP009048 Genomic DNA. Translation: BAE77622.1.
PIR	YCEC1L. A93569.
RefSeq	AP_004121.1. NP_418127.1.
3D structure databases
HSSP	HSSP built from PDB template 1N0H based on UniProtKB P07342.
ModBase	Search...
Protein-protein interaction databases
DIP	DIP:10019N.
2-D gel databases
SWISS-2DPAGE	P08142.
ECO2DBASE	D057.0. 6TH EDITION.
Genome annotation databases
GeneID	948182.
GenomeReviews	Gene locus JW3646 in contig AP009048_GR. Gene locus b3671 in contig U00096_GR.
KEGG	ecj:JW3646. eco:b3671.
Organism-specific databases
EchoBASE	EB0489.
EcoGene	EG10494. ilvB.
CMR	Search...
Phylogenomic databases
HOGENOM	P08142.
OMA	P08142. GMINFMQ.
Enzyme and pathway databases
BioCyc	EcoCyc:LARGEILVB-MON. MetaCyc:LARGEILVB-MON.
Family and domain databases
InterPro	IPR012846. Acetolactate_synth_lsu. IPR000399. TPP_bd_CS. IPR012001. TPP_bd_enzyme_N. IPR011766. TPP_enzyme_bd_C. IPR012000. TPP_enzyme_M. [Graphical view]
Pfam	PF02775. TPP_enzyme_C. 1 hit. PF00205. TPP_enzyme_M. 1 hit. PF02776. TPP_enzyme_N. 1 hit. [Graphical view]
TIGRFAMs	TIGR00118. acolac_lg. 1 hit.
PROSITE	PS00187. TPP_ENZYMES. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

ILVB_ECOLI

Accession

Primary (citable) accession number: P08142
Secondary accession number(s): Q2M7Y4

Entry history

Integrated into UniProtKB/Swiss-Prot:	August 1, 1988
Last sequence update:	August 1, 1988
Last modified:	June 16, 2009
This is version 96 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)