O50078 (ACEA_HYPME) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Isocitrate lyase
Short name=ICL
Short name=Isocitrase
Short name=Isocitratase
EC=4.1.3.1

Gene names

Name:	aceA
Synonyms:	icl

Organism

Hyphomicrobium methylovorum

Taxonomic identifier

84 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Alphaproteobacteria › Rhizobiales › Hyphomicrobiaceae › Hyphomicrobium

Protein attributes

Sequence length	540 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Catalyzes the formation of succinate and glyoxylate from isocitrate, a key step of the glyoxylate cycle. May be involved in the assimilation of one-carbon compounds via the isocitrate lyase-positive serine pathway. Ref.1
Catalytic activity	Isocitrate = succinate + glyoxylate. Ref.1
Cofactor	Divalent cations. Magnesium and, to a lesser extent, manganese. Ref.1
Enzyme regulation	In the presence of magnesium, inhibited by oxalate, potassium cyanide, manganese, silver, cadmium and to a lesser extent by succinate, glycolate, iodoacetamide, DL-penicillamine, aluminum, sodium, potassium, lithium and strontium. Ref.1
Pathway	Carbohydrate metabolism; glyoxylate cycle; (S)-malate from isocitrate: step 1/2. Ref.1
Subunit structure	Homotetramer. Ref.1
Subcellular location	Cytoplasm Probable.
Sequence similarities	Belongs to the isocitrate lyase/PEP mutase superfamily. Isocitrate lyase family.
Biophysicochemical properties	Kinetic parameters: KM=0.51 mM for D-isocitrate Ref.1 pH dependence: Optimum pH is 7.5. The enzyme is stable when incubated for 15 min at 30 degrees Celsius at pH 7.5-9. Ref.1 Temperature dependence: Optimum temperature is 45 degrees Celsius. Loss of activity is 0%, 16%, 30%, 82% and 100% when incubated at 25, 30, 40, 50 and 60 degrees Celsius for 30 min, respectively. Ref.1

Ontologies

Keywords
Biological process	Glyoxylate bypass Tricarboxylic acid cycle
Cellular component	Cytoplasm
Ligand	Magnesium Manganese Metal-binding
Molecular function	Lyase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological_process	glyoxylate cycle Inferred from direct assay Ref.1. Source: UniProtKB tricarboxylic acid cycle Inferred from direct assay Ref.1. Source: UniProtKB
Cellular_component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	isocitrate lyase activity Inferred from direct assay Ref.1. Source: UniProtKB magnesium ion binding Inferred from direct assay Ref.1. Source: UniProtKB transition metal ion binding Inferred from direct assay Ref.1. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Initiator methionine	1	1	Removed Ref.1
	Chain	2 – 540	539	Isocitrate lyase Ref.1		PRO_0000389621
Sites
	Active site	225	1	By similarity UniProtKB P0A9G6

Sequences

	Sequence		Length	Mass (Da)
	O50078 [UniParc]. Last modified June 1, 1998. Version 1. Checksum: F289F07879534A7B	FASTA	540	59,898
	10 20 30 40 50 60 MAHKKTYSQL RSELLARYPV GLTKGGVSID DIVQLRLQSP YESHLDVARA MASVMRADMA 70 80 90 100 110 120 AYDRDTGKFT QSLGCWSGFH AQQMIKAVKR LRGTTKGAYV YLSGWMVAGL RNRWGHLPDQ 130 140 150 160 170 180 SMHEKTSVVD LIEEIYVSLR QADEVALNDL FNELKDARAK GATNKACEEI ISRIDGFESH 190 200 210 220 230 240 VVPIIADIDA GFGNEHATYL LAKEMIKAGA CCLQIENQVS DAKQCGHQDG KVTVPREDFI 250 260 270 280 290 300 EKLRACRLAF EELGVDDGVI VARTDSLGAS LTQKIPVSQQ AGDFASSYIK WLKTEPITDA 310 320 330 340 350 360 NPLSEGELAI WQSGNFARPI RMPNGLFSFR EGTGRARVIE DCIASLKDGD ADLIWIETDT 370 380 390 400 410 420 PNVDEIASMV AEIRKQVPDA KLVYNNSPSF NWTLNLRKQV RAQWISEGKI AEADYPDGTA 430 440 450 460 470 480 LMSAQYDTSE LGREADDRLR QFQVDISARA GVFHNLITLP TFHLTAKSTD ELSHGYFGED 490 500 510 520 530 540 RMLAYVATVQ REEIRRSISA VRHQHEVGSD LGDTFKEMVS GDRALKAGGA HNTMNQFAAE

References

[1]

"Characterization, gene cloning and expression of isocitrate lyase involved in the assimilation of one-carbon compounds in Hyphomicrobium methylovorum GM2." Tanaka Y., Yoshida T., Watanabe K., Izumi Y., Mitsunaga T. Eur. J. Biochem. 249:820-825(1997) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 2-20, FUNCTION, CATALYTIC ACTIVITY, COFACTOR, ENZYME REGULATION, BIOPHYSICOCHEMICAL PROPERTIES, PATHWAY, SUBUNIT. Strain: GM2.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AB004651 Genomic DNA. Translation: BAA23678.1.
3D structure databases
HSSP	HSSP built from PDB template 1IGW based on UniProtKB P05313.
ProteinModelPortal	O50078.
ModBase	Search...
Proteomic databases
PRIDE	O50078.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Enzyme and pathway databases
UniPathway	UPA00703; UER00719.
Family and domain databases
Gene3D	3.20.20.60. 3 hits.
InterPro	IPR006254. Isocitrate_lyase. IPR000918. Isocitrate_lyase/Pmutase. IPR015813. Pyrv/PenolPyrv_Kinase. [Graphical view]
PANTHER	PTHR21631:SF3. PTHR21631:SF3. 1 hit.
Pfam	PF00463. ICL. 3 hits. [Graphical view]
PIRSF	PIRSF001362. Isocit_lyase. 1 hit.
SUPFAM	SSF51621. Pyrv/PenolPyrv_Kinase_cat. 1 hit.
ProtoNet	Search...

Entry information

Entry name

ACEA_HYPME

Accession

Primary (citable) accession number: O50078

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 15, 2009
Last sequence update:	June 1, 1998
Last modified:	April 3, 2013
This is version 55 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program