P0A705 (IF2_ECOLI) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Translation initiation factor IF-2

Gene names

Name:	infB
Synonyms:	ssyG
Ordered Locus Names:	b3168, JW3137

Organism

Escherichia coli (strain K12)

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia

Protein attributes

Sequence length	890 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	One of the essential components for the initiation of protein synthesis. Protects formylmethionyl-tRNA from spontaneous hydrolysis and promotes its binding to the 30S ribosomal subunits. Also involved in the hydrolysis of GTP during the formation of the 70S ribosomal complex. HAMAP MF_00100_B
Subcellular location	Cytoplasm HAMAP MF_00100_B.
Miscellaneous	When overexpressed partially suppresses the slow growth and decreased 70S ribosome phenotype of an rsgA knockout; rsgA may be involved in 30S ribosomal subunit biogenesis. HAMAP MF_00100_B
Sequence similarities	Belongs to the IF-2 family.

Ontologies

Keywords
Biological process	Protein biosynthesis
Cellular component	Cytoplasm
Coding sequence diversity	Alternative initiation
Ligand	GTP-binding Nucleotide-binding
Molecular function	Initiation factor
PTM	Acetylation
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Cellular component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell membrane Inferred from direct assay. Source: UniProtKB
Molecular function	GTP binding Inferred from electronic annotation. Source: UniProtKB-KW GTPase activity Inferred from electronic annotation. Source: InterPro translation initiation factor activity Inferred from direct assay. Source: EcoliWiki
Complete GO annotation...

Alternative products

This entry describes 3 isoforms produced by alternative initiation. [Align] [Select]

Isoform Alpha (identifier: P0A705-1)

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

Isoform Beta (identifier: P0A705-2)

The sequence of this isoform differs from the canonical sequence as follows:
     1-157: Missing.
     158-158: V → M

Isoform Beta' (identifier: P0A705-3)

The sequence of this isoform differs from the canonical sequence as follows:
     1-164: Missing.

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 890

890

Translation initiation factor IF-2 HAMAP MF_00100_B

PRO_0000238785

Regions

Nucleotide binding

398 – 405

8

GTP By similarity

Nucleotide binding

444 – 448

5

GTP By similarity

Nucleotide binding

498 – 501

4

GTP By similarity

Region

1 – 103

103

1 HAMAP MF_00100_B

Region

104 – 287

184

2 HAMAP MF_00100_B

Region

288 – 391

104

3 HAMAP MF_00100_B

Region

392 – 540

149

G-domain HAMAP MF_00100_B

Region

541 – 668

128

5 HAMAP MF_00100_B

Region

669 – 890

222

6 HAMAP MF_00100_B

Compositional bias

167 – 214

48

Ala/Arg/Glu/Lys-rich HAMAP MF_00100_B

Amino acid modifications

Modified residue

808

1

N6-acetyllysine Ref.11

Natural variations

Alternative sequence

1 – 164

164

Missing in isoform Beta'.

VSP_018760

Alternative sequence

1 – 157

157

Missing in isoform Beta.

VSP_018758

Alternative sequence

158

1

V → M in isoform Beta.

VSP_018759

Natural variant

409

1

D → E in strain: IQ489.

Natural variant

423

1

G → GG in strain: IQ490.

Natural variant

432

1

H → Q in strain: ECOAU9326.

Natural variant

490

1

Q → G in strain: ECOAU9302, ECOAU9306, ECOAU9307 and ECOAU9309.

Natural variant

684

1

G → A in strain: ECOAU9306.

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

890

Helix Strand Turn

Details...

Helix

8 – 13

6

Beta strand

14 – 16

3

Helix

17 – 27

11

Beta strand

32 – 35

4

Helix

41 – 43

3

Helix

44 – 49

6

Sequences

	Sequence		Length	Mass (Da)
	Isoform Alpha [UniParc]. Last modified June 7, 2005. Version 1. Checksum: 86B9F9B2AE773DDE	FASTA	890	97,350
	10 20 30 40 50 60 MTDVTIKTLA AERQTSVERL VQQFADAGIR KSADDSVSAQ EKQTLIDHLN QKNSGPDKLT 70 80 90 100 110 120 LQRKTRSTLN IPGTGGKSKS VQIEVRKKRT FVKRDPQEAE RLAAEEQAQR EAEEQARREA 130 140 150 160 170 180 EESAKREAQQ KAEREAAEQA KREAAEQAKR EAAEKDKVSN QQDDMTKNAQ AEKARREQEA 190 200 210 220 230 240 AELKRKAEEE ARRKLEEEAR RVAEEARRMA EENKWTDNAE PTEDSSDYHV TTSQHARQAE 250 260 270 280 290 300 DESDREVEGG RGRGRNAKAA RPKKGNKHAE SKADREEARA AVRGGKGGKR KGSSLQQGFQ 310 320 330 340 350 360 KPAQAVNRDV VIGETITVGE LANKMAVKGS QVIKAMMKLG AMATINQVID QETAQLVAEE 370 380 390 400 410 420 MGHKVILRRE NELEEAVMSD RDTGAAAEPR APVVTIMGHV DHGKTSLLDY IRSTKVASGE 430 440 450 460 470 480 AGGITQHIGA YHVETENGMI TFLDTPGHAA FTSMRARGAQ ATDIVVLVVA ADDGVMPQTI 490 500 510 520 530 540 EAIQHAKAAQ VPVVVAVNKI DKPEADPDRV KNELSQYGIL PEEWGGESQF VHVSAKAGTG 550 560 570 580 590 600 IDELLDAILL QAEVLELKAV RKGMASGAVI ESFLDKGRGP VATVLVREGT LHKGDIVLCG 610 620 630 640 650 660 FEYGRVRAMR NELGQEVLEA GPSIPVEILG LSGVPAAGDE VTVVRDEKKA REVALYRQGK 670 680 690 700 710 720 FREVKLARQQ KSKLENMFAN MTEGEVHEVN IVLKADVQGS VEAISDSLLK LSTDEVKVKI 730 740 750 760 770 780 IGSGVGGITE TDATLAAASN AILVGFNVRA DASARKVIEA ESLDLRYYSV IYNLIDEVKA 790 800 810 820 830 840 AMSGMLSPEL KQQIIGLAEV RDVFKSPKFG AIAGCMVTEG VVKRHNPIRV LRDNVVIYEG 850 860 870 880 890 ELESLRRFKD DVNEVRNGME CGIGVKNYND VRTGDVIEVF EIIEIQRTIA
	Isoform Beta [UniParc]. Checksum: A85674E0145D5E66	FASTA	733	79,745
	10 20 30 40 50 60 MSNQQDDMTK NAQAEKARRE QEAAELKRKA EEEARRKLEE EARRVAEEAR RMAEENKWTD 70 80 90 100 110 120 NAEPTEDSSD YHVTTSQHAR QAEDESDREV EGGRGRGRNA KAARPKKGNK HAESKADREE 130 140 150 160 170 180 ARAAVRGGKG GKRKGSSLQQ GFQKPAQAVN RDVVIGETIT VGELANKMAV KGSQVIKAMM 190 200 210 220 230 240 KLGAMATINQ VIDQETAQLV AEEMGHKVIL RRENELEEAV MSDRDTGAAA EPRAPVVTIM 250 260 270 280 290 300 GHVDHGKTSL LDYIRSTKVA SGEAGGITQH IGAYHVETEN GMITFLDTPG HAAFTSMRAR 310 320 330 340 350 360 GAQATDIVVL VVAADDGVMP QTIEAIQHAK AAQVPVVVAV NKIDKPEADP DRVKNELSQY 370 380 390 400 410 420 GILPEEWGGE SQFVHVSAKA GTGIDELLDA ILLQAEVLEL KAVRKGMASG AVIESFLDKG 430 440 450 460 470 480 RGPVATVLVR EGTLHKGDIV LCGFEYGRVR AMRNELGQEV LEAGPSIPVE ILGLSGVPAA 490 500 510 520 530 540 GDEVTVVRDE KKAREVALYR QGKFREVKLA RQQKSKLENM FANMTEGEVH EVNIVLKADV 550 560 570 580 590 600 QGSVEAISDS LLKLSTDEVK VKIIGSGVGG ITETDATLAA ASNAILVGFN VRADASARKV 610 620 630 640 650 660 IEAESLDLRY YSVIYNLIDE VKAAMSGMLS PELKQQIIGL AEVRDVFKSP KFGAIAGCMV 670 680 690 700 710 720 TEGVVKRHNP IRVLRDNVVI YEGELESLRR FKDDVNEVRN GMECGIGVKN YNDVRTGDVI 730 EVFEIIEIQR TIA
	Isoform Beta' [UniParc]. Checksum: 08C16925C01D0199	FASTA	726	78,927
	10 20 30 40 50 60 MTKNAQAEKA RREQEAAELK RKAEEEARRK LEEEARRVAE EARRMAEENK WTDNAEPTED 70 80 90 100 110 120 SSDYHVTTSQ HARQAEDESD REVEGGRGRG RNAKAARPKK GNKHAESKAD REEARAAVRG 130 140 150 160 170 180 GKGGKRKGSS LQQGFQKPAQ AVNRDVVIGE TITVGELANK MAVKGSQVIK AMMKLGAMAT 190 200 210 220 230 240 INQVIDQETA QLVAEEMGHK VILRRENELE EAVMSDRDTG AAAEPRAPVV TIMGHVDHGK 250 260 270 280 290 300 TSLLDYIRST KVASGEAGGI TQHIGAYHVE TENGMITFLD TPGHAAFTSM RARGAQATDI 310 320 330 340 350 360 VVLVVAADDG VMPQTIEAIQ HAKAAQVPVV VAVNKIDKPE ADPDRVKNEL SQYGILPEEW 370 380 390 400 410 420 GGESQFVHVS AKAGTGIDEL LDAILLQAEV LELKAVRKGM ASGAVIESFL DKGRGPVATV 430 440 450 460 470 480 LVREGTLHKG DIVLCGFEYG RVRAMRNELG QEVLEAGPSI PVEILGLSGV PAAGDEVTVV 490 500 510 520 530 540 RDEKKAREVA LYRQGKFREV KLARQQKSKL ENMFANMTEG EVHEVNIVLK ADVQGSVEAI 550 560 570 580 590 600 SDSLLKLSTD EVKVKIIGSG VGGITETDAT LAAASNAILV GFNVRADASA RKVIEAESLD 610 620 630 640 650 660 LRYYSVIYNL IDEVKAAMSG MLSPELKQQI IGLAEVRDVF KSPKFGAIAG CMVTEGVVKR 670 680 690 700 710 720 HNPIRVLRDN VVIYEGELES LRRFKDDVNE VRNGMECGIG VKNYNDVRTG DVIEVFEIIE IQRTIA

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Sequence of the initiation factor IF2 gene: unusual protein features and homologies with elongation factors." Sacerdot C., Dessen P., Hershey J.W.B., Plumbridge J.A., Grunberg-Manago M. Proc. Natl. Acad. Sci. U.S.A. 81:7787-7791(1984) [PubMed: 6096856] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"E. coli translation initiation factor IF2--an extremely conserved protein. Comparative sequence analysis of the infB gene in clinical isolates of E. coli." Steffensen S.A.D.A., Poulsen A.B., Mortensen K.K., Sperling-Petersen H.U. FEBS Lett. 419:281-284(1997) [PubMed: 9428651] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: Various clinical strains.
[3]	"Sequence of the infB gene from Escherichia coli strain IQ489 and IQ490." Hedegaard J., Kristensen J.E., Nakamura Y., Sperling-Petersen H.U., Mortensen K.K. Submitted (FEB-1999) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: IQ489 and IQ490.
[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.
[6]	"The nucleotide sequence of the cloned nusA gene and its flanking region of Escherichia coli." Ishii S., Ihara M., Maekawa T., Nakamura Y., Uchida H., Imamoto F. Nucleic Acids Res. 12:3333-3342(1984) [PubMed: 6326058] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-22.
[7]	"The existence of two genes between infB and rpsO in the Escherichia coli genome: DNA sequencing and S1 nuclease mapping." Sands J.F., Regnier P., Cummings H.S., Grunberg-Manago M., Hershey J.W.B. Nucleic Acids Res. 16:10803-10816(1988) [PubMed: 2849753] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 864-890.
[8]	"Tandem translation of E. coli initiation factor IF2 beta: purification and characterization in vitro of two active forms." Nyengaard N.R., Mortensen K.K., Lassen S.F., Hershey J.W.B., Sperling-Petersen H.U. Biochem. Biophys. Res. Commun. 181:1572-1579(1991) [PubMed: 1764105] [Abstract] Cited for: PROTEIN SEQUENCE OF 159-174 (ISOFORMS BETA AND BETA').
[9]	"Structural and functional domains of E coli initiation factor IF2." Laalami S., Sacerdot C., Vachon G., Mortensen K., Sperling-Petersen H.U., Cenatiempo Y., Grunberg-Manago M. Biochimie 73:1557-1566(1991) [PubMed: 1805969] [Abstract] Cited for: DOMAIN STRUCTURE.
[10]	"Genetic interaction screens with ordered overexpression and deletion clone sets implicate the Escherichia coli GTPase YjeQ in late ribosome biogenesis." Campbell T.L., Brown E.D. J. Bacteriol. 190:2537-2545(2008) [PubMed: 18223068] [Abstract] Cited for: PARTIALLY SUPPRESSES A RSGA MUTANT. Strain: K12.
[11]	"Lysine acetylation is a highly abundant and evolutionarily conserved modification in Escherichia coli." Zhang J., Sprung R., Pei J., Tan X., Kim S., Zhu H., Liu C.F., Grishin N.V., Zhao Y. Mol. Cell. Proteomics 8:215-225(2009) [PubMed: 18723842] [Abstract] Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT LYS-808, MASS SPECTROMETRY. Strain: K12 / JW1106 and K12 / MG1655 / ATCC 47076.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

X00513 Genomic DNA. Translation: CAA25201.1.
X00513 Genomic DNA. Translation: CAA25202.1.
U18997 Genomic DNA. Translation: AAA57971.1.
U00096 Genomic DNA. Translation: AAC76202.1.
AP009048 Genomic DNA. Translation: BAE77214.1.
AJ002537 Genomic DNA. Translation: CAA05529.1.
AJ002537 Genomic DNA. Translation: CAA05530.1.
AJ002537 Genomic DNA. Translation: CAA05531.1.
AJ002538 Genomic DNA. Translation: CAA05532.1.
AJ002538 Genomic DNA. Translation: CAA05533.1.
AJ002538 Genomic DNA. Translation: CAA05534.1.
AJ002539 Genomic DNA. Translation: CAA05535.1.
AJ002539 Genomic DNA. Translation: CAA05536.1.
AJ002539 Genomic DNA. Translation: CAA05537.1.
AJ002540 Genomic DNA. Translation: CAA05538.1.
AJ002540 Genomic DNA. Translation: CAA05539.1.
AJ002540 Genomic DNA. Translation: CAA05540.1.
AJ002541 Genomic DNA. Translation: CAA05541.1.
AJ002541 Genomic DNA. Translation: CAA05542.1.
AJ002541 Genomic DNA. Translation: CAA05543.1.
AJ002542 Genomic DNA. Translation: CAA05544.1.
AJ002542 Genomic DNA. Translation: CAA05545.1.
AJ002542 Genomic DNA. Translation: CAA05546.1.
AJ002402 Genomic DNA. Translation: CAA05386.1.
AJ002403 Genomic DNA. Translation: CAA05387.1.
AJ002404 Genomic DNA. Translation: CAA05388.1.
AJ002405 Genomic DNA. Translation: CAA05389.1.
AJ002406 Genomic DNA. Translation: CAA05390.1.
AJ002407 Genomic DNA. Translation: CAA05391.1.
AJ002408 Genomic DNA. Translation: CAA05392.1.
AJ002409 Genomic DNA. Translation: CAA05393.1.
AJ002410 Genomic DNA. Translation: CAA05394.1.
AJ002411 Genomic DNA. Translation: CAA05395.1.
AJ002412 Genomic DNA. Translation: CAA05396.1.
AJ002413 Genomic DNA. Translation: CAA05397.1.
AJ132861 Genomic DNA. Translation: CAC20126.1.
AJ132861 Genomic DNA. Translation: CAC20127.1.
AJ132861 Genomic DNA. Translation: CAC20128.1.
AJ132862 Genomic DNA. Translation: CAC20130.1.
AJ132862 Genomic DNA. Translation: CAC20131.1.
AJ132862 Genomic DNA. Translation: CAC20132.1.
X13775 Genomic DNA. Translation: CAA32019.1.

PIR

FIEC2. D65107.

RefSeq

NP_417637.1. NC_000913.2.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1ND9	NMR	-	A	2-50	[»]
1ZO1	electron microscopy	13.80	I	388-888	[»]

ProteinModelPortal

P0A705.

SMR

P0A705. Positions 2-50, 388-887.

ModBase

Search...

Protein-protein interaction databases

DIP

DIP-36182N.

IntAct

P0A705. 45 interactions.

MINT

MINT-1235405.

PTM databases

PhosSite

P0A705.

2D gel databases

ECO2DBASE

F119.0. 6TH EDITION.
G117.0. 6TH EDITION.

Proteomic databases

PRIDE

P0A705.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

GeneID

947684.

GenomeReviews

Gene locus JW3137 in contig AP009048_GR.
Gene locus b3168 in contig U00096_GR.

KEGG

ecj:JW3137.
eco:b3168.

PATRIC

32121754. VBIEscCol129921_3263.

Organism-specific databases

EchoBASE

EB0500.

EcoGene

EG10505. infB.

Phylogenomic databases

GeneTree

EBGT00050000008366.

OMA

NILGIAE.

PhylomeDB

P0A705.

ProtClustDB

PRK05306.

Enzyme and pathway databases

BioCyc

EcoCyc:EG10505-MONOMER.

Gene expression databases

Genevestigator

P0A705.

Family and domain databases

HAMAP

MF_00100_B. IF-2_B.
[Tree]

InterPro

IPR009061. DNA-bd_dom_put.
IPR013575. IF2_assoc_dom_bac.
IPR006847. IF2_N.
IPR000795. ProtSyn_GTP-bd.
IPR005225. Small_GTP-bd_dom.
IPR000178. TF_IF2_bacterial-like.
IPR015760. TIF_IF2.
IPR023115. TIF_IF2_dom3.
IPR004161. Transl_elong_EFTu/EF1A_2.
IPR009000. Transl_elong_init/rib_B-barrel.
[Graphical view]

Gene3D

G3DSA:3.40.50.10050. TIF_IF2_dom3. 1 hit.

KO

K02519.

PANTHER

PTHR23115:SF41. aIF-2. 1 hit.

Pfam

PF00009. GTP_EFTU. 1 hit.
PF03144. GTP_EFTU_D2. 2 hits.
PF11987. IF-2. 1 hit.
PF08364. IF2_assoc. 1 hit.
PF04760. IF2_N. 2 hits.
[Graphical view]

SUPFAM

SSF46955. Putativ_DNA_bind. 1 hit.
SSF52156. TIF_IF2_dom3. 1 hit.
SSF50447. Translat_factor. 2 hits.

TIGRFAMs

TIGR00487. IF-2. 1 hit.
TIGR00231. Small_GTP. 1 hit.

PROSITE

PS01176. IF2. 1 hit.
[Graphical view]

ProtoNet

Search...

Entry information

Entry name

IF2_ECOLI

Accession

Primary (citable) accession number: P0A705
Secondary accession number(s): O32548 , O32549, O32550, O34379, O34415, O34603, P02995, Q2M942, Q9EUZ4, Q9EUZ5, Q9EUZ6, Q9EUZ8, Q9EUZ9, Q9EV00

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	June 7, 2005
Last modified:	January 25, 2012
This is version 71 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program