Reviewed, UniProtKB/Swiss-Prot P10408 (SECA_ECOLI)

Names and origin

Protein names

Recommended name:
    Protein translocase subunit secA

Gene names

Name:	secA
Synonyms:	azi, pea, prlD
Ordered Locus Names:	b0098, JW0096

Organism

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

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia

Protein attributes

Sequence length	901 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Required for protein export, interacts with the secYEG preprotein conducting channel. SecA has a central role in coupling the hydrolysis of ATP to the transfer of proteins into and across the cell membrane, serving both as a receptor for the preprotein-secB complex and as an ATP-driven molecular motor driving the stepwise translocation of polypeptide chains across the membrane. HAMAP MF_01382
Cofactor	Binds 1 zinc ion per subunit. Zinc is required for binding of the secB chaperone to the extreme C-terminus of secA. Ref.7
Subunit structure	Monomer and homodimer; probably dimeric in the cytoplasm. It is not yet clear whether the form that functions in protein insertion is monomeric or dimeric. Part of the essential protein translocation apparatus which comprises secA, secYEG and auxiliary proteins secDFyajC and yidC/oxaA. Ref.10 Ref.11
Subcellular location	Cell inner membrane; Peripheral membrane protein; Cytoplasmic side. Cytoplasm. Note: Distribution is 50-50. HAMAP MF_01382
Induction	Repressed under conditions of excess protein secretion capacity and derepressed when protein secretion becomes limiting. This is regulated by secM. HAMAP MF_01382
Sequence similarities	Belongs to the secA family.

Ontologies

Keywords
Biological process	Protein transport Translocation Transport
Cellular component	Cell inner membrane Cell membrane Cytoplasm Membrane
Ligand	ATP-binding Metal-binding Nucleotide-binding Zinc
Technical term	3D-structure Complete proteome Direct protein sequencing
Gene Ontology (GO)
Biological process	intracellular protein transmembrane transport Inferred from electronic annotation. Source: HAMAP protein import Inferred from electronic annotation. Source: InterPro protein targeting Inferred from electronic annotation. Source: HAMAP
Cellular component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell internal side of plasma membrane Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	ATP binding Inferred from electronic annotation. Source: HAMAP protein binding Inferred from physical interaction. Source: IntAct zinc ion binding Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Binary interactions

With	Entry	#Exp.	IntAct	Notes
lamB	P02943	2	EBI-543213,EBI-371309
phoA	P00634	1	EBI-543213,EBI-552958
secY	P0AGA2	1	EBI-543213,EBI-761422
ybgC	P0A8Z3	1	EBI-543213,EBI-543276

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 901

901

Protein translocase subunit secA HAMAP MF_01382

PRO_0000109585

Regions

Nucleotide binding

102 – 109

8

ATP Potential

Sites

Metal binding

885

1

Zinc HAMAP MF_01382

Metal binding

887

1

Zinc HAMAP MF_01382

Metal binding

896

1

Zinc HAMAP MF_01382

Metal binding

897

1

Zinc HAMAP MF_01382

Experimental info

Sequence conflict

19

1

R → G AA sequence Ref.1

Sequence conflict

737 – 738

2

ER → DG in AAA24619. Ref.1

Sequence conflict

737 – 738

2

ER → DG in CAA38875. Ref.2

Secondary structure

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901

Helix Strand Turn

Details...

Helix

14 – 30

17

Helix

32 – 37

6

Helix

40 – 55

16

Helix

60 – 79

20

Helix

85 – 95

11

Beta strand

96 – 101

6

Helix

108 – 120

13

Beta strand

127 – 132

6

Helix

133 – 149

17

Beta strand

154 – 156

3

Helix

163 – 171

9

Beta strand

172 – 178

7

Helix

179 – 189

11

Helix

195 – 197

3

Beta strand

205 – 209

5

Helix

211 – 214

4

Turn

215 – 220

6

Beta strand

222 – 227

6

Beta strand

370 – 376

7

Helix

377 – 381

5

Beta strand

384 – 391

8

Helix

398 – 405

8

Beta strand

408 – 411

4

Beta strand

426 – 430

5

Helix

431 – 446

16

Turn

447 – 449

3

Beta strand

452 – 458

7

Helix

459 – 471

13

Helix

484 – 492

9

Turn

493 – 495

3

Beta strand

500 – 505

6

Helix

519 – 525

7

Helix

533 – 550

18

Beta strand

553 – 560

8

Helix

565 – 572

8

Helix

577 – 579

3

Beta strand

582 – 589

8

Helix

593 – 596

4

Helix

601 – 604

4

Helix

605 – 610

6

Helix

621 – 668

48

Helix

673 – 689

17

Helix

698 – 700

3

Helix

703 – 714

12

Helix

720 – 726

7

Helix

732 – 754

23

Helix

756 – 787

32

Turn

788 – 790

3

Beta strand

791 – 793

3

Beta strand

795 – 797

3

Turn

799 – 801

3

Helix

802 – 828

27

Turn

884 – 887

4

Beta strand

889 – 891

3

Helix

892 – 896

5

Sequences

	Sequence		Length	Mass (Da)
	P10408-1 [UniParc]. Last modified November 1, 1997. Version 2. Checksum: 683D66DD4305DBC2	FASTA	901	102,023
	10 20 30 40 50 60 MLIKLLTKVF GSRNDRTLRR MRKVVNIINA MEPEMEKLSD EELKGKTAEF RARLEKGEVL 70 80 90 100 110 120 ENLIPEAFAV VREASKRVFG MRHFDVQLLG GMVLNERCIA EMRTGEGKTL TATLPAYLNA 130 140 150 160 170 180 LTGKGVHVVT VNDYLAQRDA ENNRPLFEFL GLTVGINLPG MPAPAKREAY AADITYGTNN 190 200 210 220 230 240 EYGFDYLRDN MAFSPEERVQ RKLHYALVDE VDSILIDEAR TPLIISGPAE DSSEMYKRVN 250 260 270 280 290 300 KIIPHLIRQE KEDSETFQGE GHFSVDEKSR QVNLTERGLV LIEELLVKEG IMDEGESLYS 310 320 330 340 350 360 PANIMLMHHV TAALRAHALF TRDVDYIVKD GEVIIVDEHT GRTMQGRRWS DGLHQAVEAK 370 380 390 400 410 420 EGVQIQNENQ TLASITFQNY FRLYEKLAGM TGTADTEAFE FSSIYKLDTV VVPTNRPMIR 430 440 450 460 470 480 KDLPDLVYMT EAEKIQAIIE DIKERTAKGQ PVLVGTISIE KSELVSNELT KAGIKHNVLN 490 500 510 520 530 540 AKFHANEAAI VAQAGYPAAV TIATNMAGRG TDIVLGGSWQ AEVAALENPT AEQIEKIKAD 550 560 570 580 590 600 WQVRHDAVLE AGGLHIIGTE RHESRRIDNQ LRGRSGRQGD AGSSRFYLSM EDALMRIFAS 610 620 630 640 650 660 DRVSGMMRKL GMKPGEAIEH PWVTKAIANA QRKVESRNFD IRKQLLEYDD VANDQRRAIY 670 680 690 700 710 720 SQRNELLDVS DVSETINSIR EDVFKATIDA YIPPQSLEEM WDIPGLQERL KNDFDLDLPI 730 740 750 760 770 780 AEWLDKEPEL HEETLRERIL AQSIEVYQRK EEVVGAEMMR HFEKGVMLQT LDSLWKEHLA 790 800 810 820 830 840 AMDYLRQGIH LRGYAQKDPK QEYKRESFSM FAAMLESLKY EVISTLSKVQ VRMPEEVEEL 850 860 870 880 890 900 EQQRRMEAER LAQMQQLSHQ DDDSAAAAAL AAQTGERKVG RNDPCPCGSG KKYKQCHGRL Q

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Nucleotide sequence of the secA gene and secA(Ts) mutations preventing protein export in Escherichia coli." Schmidt M., Rollo E., Grodberg J., Oliver D. J. Bacteriol. 170:3404-3414(1988) [PubMed: 2841285] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 1-25. Strain: K12 / MC4100 / ATCC 35695 / DSM 6574.
[2]	"Systematic sequencing of the Escherichia coli genome: analysis of the 0-2.4 min region." Yura T., Mori H., Nagai H., Nagata T., Ishihama A., Fujita N., Isono K., Mizobuchi K., Nakata A. Nucleic Acids Res. 20:3305-3308(1992) [PubMed: 1630901] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12.
[3]	"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.
[4]	"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], SEQUENCE REVISION TO 737-738. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[5]	"Sequence analysis, transcriptional organization, and insertional mutagenesis of the envA gene of Escherichia coli." Beall B., Lutkenhaus J. J. Bacteriol. 169:5408-5415(1987) [PubMed: 2824434] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-67. Strain: K12.
[6]	"SecA protein hydrolyzes ATP and is an essential component of the protein translocation ATPase of Escherichia coli." Lill R., Cunningham K., Brundage L.A., Ito K., Oliver D., Wickner W. EMBO J. 8:961-966(1989) [PubMed: 2542029] [Abstract] Cited for: ATP HYDROLYSIS.
[7]	"Zinc stabilizes the SecB binding site of SecA." Fekkes P., de Wit J.G., Boorsma A., Friesen R.H.E., Driessen A.J.M. Biochemistry 38:5111-5116(1999) [PubMed: 10213615] [Abstract] Cited for: COFACTOR.
[8]	"Dissociation of the dimeric SecA ATPase during protein translocation across the bacterial membrane." Or E., Navon A., Rapoport T. EMBO J. 21:4470-4479(2002) [PubMed: 12198149] [Abstract] Cited for: DIMER DISSOCIATION IN THE PRESENCE OF ACIDIC PHOSPHOLIPIDS, DETERGENTS, SYNTHETIC SIGNAL PEPTIDES.
[9]	"Binding, activation and dissociation of the dimeric SecA ATPase at the dimeric SecYEG translocase." Duong F. EMBO J. 22:4375-4384(2003) [PubMed: 12941690] [Abstract] Cited for: ASSOCIATION OF MONOMER WITH SECYEG TRANSLOCATION COMPLEX.
[10]	"Phospholipid-induced monomerization and signal-peptide-induced oligomerization of SecA." Benach J., Chou Y.T., Fak J.J., Itkin A., Nicolae D.D., Smith P.C., Wittrock G., Floyd D.L., Golsaz C.M., Gierasch L.M., Hunt J.F. J. Biol. Chem. 278:3628-3638(2003) [PubMed: 12403785] [Abstract] Cited for: ACIDIC PHOSPHOLIPIDS, SYNTHETIC SIGNAL PEPTIDES, OLIGOMERIZATION STATE OF SECA.
[11]	"Nucleotide binding induces changes in the oligomeric state and conformation of Sec A in a lipid environment: a small-angle neutron-scattering study." Bu Z., Wang L., Kendall D.A. J. Mol. Biol. 332:23-30(2003) [PubMed: 12946344] [Abstract] Cited for: NUCLEOTIDE TURNOVER, OLIGOMERIZATION STATE OF SECA.
[12]	"Preprotein-controlled catalysis in the helicase motor of SecA." Karamanou S., Gouridis G., Papanikou E., Sianidis G., Gelis I., Keramisanou D., Vrontou E., Kalodimos C.G., Economou A. EMBO J. 26:2904-2914(2007) [PubMed: 17525736] [Abstract] Cited for: CONTROL OF ATPASE ACTIVITY.
[13]	"NMR structure of the C-terminal domain of SecA in the free state." Matousek W.M., Alexandrescu A.T. Biochim. Biophys. Acta 1702:163-171(2004) [PubMed: 15488768] [Abstract] Cited for: STRUCTURE BY NMR OF 880-901.
[14]	"Structure of dimeric SecA, the Escherichia coli preprotein translocase motor." Papanikolau Y., Papadovasilaki M., Ravelli R.B.G., McCarthy A.A., Cusack S., Economou A., Petratos K. J. Mol. Biol. 366:1545-1557(2007) [PubMed: 17229438] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS) OF 9-861 AS A DIMERIC APOPROTEIN, AS A NUCLEOTIDE-BOUND DIMER.
[15]	"Control of SecA and SecM translation by protein secretion." Nakatogawa H., Murakami A., Ito K. Curr. Opin. Microbiol. 7:145-150(2004) [PubMed: 15063851] [Abstract] Cited for: REVIEW OF PROTEIN SECRETION CONTROL OF SECA EXPRESSION.
[16]	"Bacterial protein secretion through the translocase nanomachine." Papanikou E., Karamanou S., Economou A. Nat. Rev. Microbiol. 5:839-851(2007) [PubMed: 17938627] [Abstract] Cited for: REVIEW OF PROTEIN SECRETION.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBLGenBankDDBJ

M20791 Genomic DNA. Translation: AAA24619.1.
M19211 Genomic DNA. Translation: AAA83851.1.
X55034 Genomic DNA. Translation: CAA38875.1.
U00096 Genomic DNA. Translation: AAC73209.1.
AP009048 Genomic DNA. Translation: BAB96666.2.

PIR

BVECCA. B64732.

RefSeq

AP_000761.1.
NP_414640.1.

3D structure databases

PDBPDBe

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1TM6	NMR	-	A	880-901	[»]
2FSF	X-ray	2.00	A/B	9-861	[»]
2FSG	X-ray	2.20	A/B	9-861	[»]
2FSH	X-ray	2.00	A/B	9-861	[»]
2FSI	X-ray	2.11	A/B	9-861	[»]
2VDA	NMR	-	A	9-836	[»]
3BXZ	X-ray	3.00	A/B	6-609	[»]

ModBase

Search...

Protein-protein interaction databases

DIP

DIP:10840N.

IntAct

P10408. 75 interactions.

STRING

P10408.

Protein family/group databases

TCDB

3.A.5.1.1. general secretory pathway (Sec) family.

Proteomic databases

PRIDE

P10408.

Genome annotation databases

GeneID

944821.

GenomeReviews

Gene locus JW0096 in contig AP009048_GR.
Gene locus b0098 in contig U00096_GR.

KEGG

ecj:JW0096.
eco:b0098.

Organism-specific databases

EchoBASE

EB0929.

EcoGene

EG10936. secA.

CMR

Search...

Phylogenomic databases

HOGENOM

P10408.

OMA

LTGRGVH.

Enzyme and pathway databases

BioCyc

EcoCyc:SECA.

Gene expression databases

Genevestigator

P10408.

Family and domain databases

HAMAP

MF_01382.
[Tree]

InterPro

IPR004027. SEC_C_motif.
IPR000185. SecA.
IPR011115. SecA_DEAD.
IPR014018. SecA_motor_DEAD.
IPR011130. SecA_PP_bd.
IPR011116. SecA_Wing/Scaffold.
[Graphical view]

Gene3D

G3DSA:1.10.3060.10. SecA_SW. 1 hit.

Pfam

PF02810. SEC-C. 1 hit.
PF07517. SecA_DEAD. 1 hit.
PF01043. SecA_PP_bind. 1 hit.
PF07516. SecA_SW. 1 hit.
[Graphical view]

PRINTS

PR00906. SECA.

TIGRFAMs

TIGR00963. secA. 1 hit.

PROSITE

PS01312. SECA. 1 hit.
PS51196. SECA_MOTOR_DEAD. 1 hit.
[Graphical view]

ProtoNet

Search...

Entry information

Entry name

SECA_ECOLI

Accession

Primary (citable) accession number: P10408
Secondary accession number(s): P75642

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 1, 1989
Last sequence update:	November 1, 1997
Last modified:	November 3, 2009
This is version 103 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)