P32173 (MOBA_ECOLI) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Molybdenum cofactor guanylyltransferase
Short name=MoCo guanylyltransferase
EC=2.7.7.77

Alternative name(s):
GTP:molybdopterin guanylyltransferase
Mo-MPT guanylyltransferase
Molybdopterin guanylyltransferase
Molybdopterin-guanine dinucleotide biosynthesis protein A
Molybdopterin-guanine dinucleotide synthase
Short name=MGD synthase
Protein FA

Gene names

Name:	mobA
Synonyms:	chlB, mob, narB
Ordered Locus Names:	b3857, JW3829

Organism

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

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia › Escherichia coli

Protein attributes

Sequence length	194 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Transfers a GMP moiety from GTP to Mo-molybdopterin (Mo-MPT) cofactor (Moco or molybdenum cofactor) to form Mo-molybdopterin guanine dinucleotide (Mo-MGD) cofactor. Is also involved in the biosynthesis of the bis-MGD form of the Moco cofactor (Mo-bisMGD) in which the metal is symmetrically ligated by the dithiolene groups of two MGD molecules. Is necessary and sufficient for the in vitro activation of the DMSOR molybdoenzyme that uses the Mo-bisMGD form of molybdenum cofactor, which implies formation and efficient insertion of the cofactor into the enzyme without the need of a chaperone. Is specific for GTP since other nucleotides such as ATP and GMP can not be utilized. Ref.5 Ref.6 Ref.7 Ref.9
Catalytic activity	GTP + molybdenum cofactor = diphosphate + guanylyl molybdenum cofactor. Ref.7 Ref.9
Cofactor	Magnesium or manganese. Both divalent cations appear to be equally efficient in an vitro reconstitution assay. Ref.7 Ref.10
Subunit structure	Monomer. An equilibrium exists between a monomeric and oligomeric form of the enzyme, which could be an octamer; whether this oligomeric arrangement is of functional relevance is unclear. Interacts with MoeA and MobB in vivo. Ref.5 Ref.8 Ref.10
Subcellular location	Cytoplasm HAMAP-Rule MF_00316.
Induction	Is expressed at very low levels under both aerobic and anaerobic growth conditions. Ref.4
Domain	The N-terminal domain determines nucleotide recognition and specific binding, while the C-terminal domain determines the specific binding to the target protein. When the N-terminal domain of MobA is fused to the C-terminal domain of MocA, comparable kinetic constants as wild-type MobA are obtained with GTP, and the activity with CTP is completely lost. Consistent results are obtained when the N-terminal domain of MocA is fused to the C-terminal domain of MobA: the kinetic constants with CTP are comparable with the ones found for wild-type MocA, although no activity with GTP is detected. Ref.9
Disruption phenotype	Cells lacking this gene are chlorate-resistant, fail to synthesize MGD and accumulate elevated quantities of MPT. Ref.6
Sequence similarities	Belongs to the MobA family.
Biophysicochemical properties	Kinetic parameters: KM=6.5 µM for GTP Ref.9

Ontologies

Keywords
Biological process	Molybdenum cofactor biosynthesis
Cellular component	Cytoplasm
Ligand	GTP-binding Magnesium Manganese Metal-binding Nucleotide-binding
Molecular function	Transferase
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Biological_process	Mo-molybdopterin cofactor biosynthetic process Inferred from electronic annotation. Source: UniProtKB-KW
Cellular_component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	GTP binding Inferred from electronic annotation. Source: HAMAP guanylyltransferase activity Inferred from electronic annotation. Source: HAMAP metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Binary interactions

With	Entry	#Exp.	IntAct	Notes
moeA	P12281	3	EBI-1133881,EBI-554393

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 194

194

Molybdenum cofactor guanylyltransferase HAMAP-Rule MF_00316

PRO_0000134887

Regions

Nucleotide binding

12 – 14

3

GTP HAMAP-Rule MF_00316

Sites

Metal binding

101

1

Magnesium

Binding site

25

1

GTP

Binding site

53

1

GTP

Binding site

71

1

GTP

Binding site

101

1

GTP

Experimental info

Mutagenesis

12 – 14

3

LAG → TAA: 7.5-fold decrease in affinity for GTP and nearly no effect on catalytic activity. Displays a 3-fold decrease in activity with GTP and gains a low activity with CTP as substrate; when associated with 79-LLTS-82. Ref.9

Mutagenesis

15

1

G → L: Complete loss of catalytic activity. Still capable of binding MPT and MGD and interacting with both MoeA and MobB. Ref.12

Mutagenesis

19

1

R → A: Slight reduction in catalytic activity. Ref.12

Mutagenesis

22

1

G → L: Nearly no effect on catalytic activity. Ref.12

Mutagenesis

25

1

K → A: Marked reduction in catalytic activity. Still capable of interacting with both MoeA and MobB. Ref.12

Mutagenesis

78

1

G → L: Nearly no effect on catalytic activity. Ref.12

Mutagenesis

79 – 82

4

PLAG → LLTS: 11-fold decrease in affinity for GTP and nearly no effect on catalytic activity. Displays a 3-fold decrease in activity with GTP and gains a low activity with CTP as substrate; when associated with 12-TAA-14. Ref.9 Ref.12

Mutagenesis

82

1

G → L: Slight reduction in catalytic activity. Ref.12

Mutagenesis

101

1

D → A: Complete loss of catalytic activity. Ref.12

Mutagenesis

101

1

D → N: Marked reduction in catalytic activity. Still capable of interacting with both MoeA and MobB. Ref.12

Mutagenesis

156

1

R → A: Nearly no effect on catalytic activity. Ref.12

Mutagenesis

180

1

N → D: Nearly no effect on catalytic activity. Ref.12

Mutagenesis

182

1

N → D: Nearly no effect on catalytic activity. Ref.12

Secondary structure

1

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194

Helix Strand Turn

Details...

Helix

3 – 5

3

Beta strand

6 – 12

7

Beta strand

18 – 20

3

Helix

25 – 27

3

Beta strand

28 – 30

3

Helix

35 – 46

12

Beta strand

50 – 53

4

Beta strand

55 – 57

3

Helix

58 – 62

5

Beta strand

67 – 69

3

Helix

79 – 89

11

Beta strand

92 – 99

8

Helix

109 – 115

7

Turn

116 – 119

4

Beta strand

121 – 126

6

Beta strand

131 – 139

9

Helix

142 – 151

10

Helix

157 – 163

7

Beta strand

167 – 170

4

Turn

175 – 178

4

Helix

184 – 188

5

Sequences

	Sequence		Length	Mass (Da)
	P32173 [UniParc]. Last modified October 1, 1993. Version 1. Checksum: B79B32DD7348DD48	FASTA	194	21,643
	10 20 30 40 50 60 MNLMTTITGV VLAGGKARRM GGVDKGLLEL NGKPLWQHVA DALMTQLSHV VVNANRHQEI 70 80 90 100 110 120 YQASGLKVIE DSLADYPGPL AGMLSVMQQE AGEWFLFCPC DTPYIPPDLA ARLNHQRKDA 130 140 150 160 170 180 PVVWVHDGER DHPTIALVNR AIEPLLLEYL QAGERRVMVF MRLAGGHAVD FSDHKDAFVN 190 VNTPEELARW QEKR

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Analysis of the Escherichia coli genome. III. DNA sequence of the region from 87.2 to 89.2 minutes." Plunkett G. III, Burland V., Daniels D.L., Blattner F.R. Nucleic Acids Res. 21:3391-3398(1993) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[2]	"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] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[3]	"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] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[4]	"The mob locus of Escherichia coli K12 required for molybdenum cofactor biosynthesis is expressed at very low levels." Iobbi-Nivol C., Palmer T., Whitty P.W., McNairn E., Boxer D.H. Microbiology 141:1663-1671(1995) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], INDUCTION. Strain: K12.
[5]	"Isolation of protein FA, a product of the mob locus required for molybdenum cofactor biosynthesis in Escherichia coli." Palmer T., Vasishta A., Whitty P.W., Boxer D.H. Eur. J. Biochem. 222:687-692(1994) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 1-5, FUNCTION IN MGD BIOSYNTHESIS, SUBUNIT.
[6]	"Molybdenum cofactor biosynthesis in Escherichia coli. Requirement of the chlB gene product for the formation of molybdopterin guanine dinucleotide." Johnson J.L., Indermaur L.W., Rajagopalan K.V. J. Biol. Chem. 266:12140-12145(1991) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION IN MGD BIOSYNTHESIS, DISRUPTION PHENOTYPE. Strain: RK4353.
[7]	"Mechanism of assembly of the bis(molybdopterin guanine dinucleotide)molybdenum cofactor in Rhodobacter sphaeroides dimethyl sulfoxide reductase." Temple C.A., Rajagopalan K.V. J. Biol. Chem. 275:40202-40210(2000) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION IN BIS(MGD) AND MGD BIOSYNTHESIS, CATALYTIC ACTIVITY, SUBSTRATE SPECIFICITY, COFACTOR. Strain: K12 / MC4100 / ATCC 35695 / DSM 6574.
[8]	"In vivo interactions between gene products involved in the final stages of molybdenum cofactor biosynthesis in Escherichia coli." Magalon A., Frixon C., Pommier J., Giordano G., Blasco F. J. Biol. Chem. 277:48199-48204(2002) [PubMed] [Europe PMC] [Abstract] Cited for: INTERACTION WITH MOEA AND MOBB. Strain: K12 / MC4100 / ATCC 35695 / DSM 6574.
[9]	"Molybdopterin dinucleotide biosynthesis in Escherichia coli: identification of amino acid residues of molybdopterin dinucleotide transferases that determine specificity for binding of guanine or cytosine nucleotides." Neumann M., Seduk F., Iobbi-Nivol C., Leimkuhler S. J. Biol. Chem. 286:1400-1408(2011) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION, CATALYTIC ACTIVITY, KINETIC PARAMETERS, DOMAIN, MUTAGENESIS OF 12-LEU--GLY-14 AND 79-PRO--GLY-82.
[10]	"The crystal structure of the Escherichia coli MobA protein provides insight into molybdopterin guanine dinucleotide biosynthesis." Lake M.W., Temple C.A., Rajagopalan K.V., Schindelin H. J. Biol. Chem. 275:40211-40217(2000) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.65 ANGSTROMS) OF APOENZYME AND IN COMPLEX WITH MN-GTP, COFACTOR, SUBUNIT. Strain: K12 / MC4100 / ATCC 35695 / DSM 6574.
[11]	"Crystal structure of the molybdenum cofactor biosynthesis protein MobA from Escherichia coli at near-atomic resolution." Stevenson C.E., Sargent F., Buchanan G., Palmer T., Lawson D.M. Structure 8:1115-1125(2000) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.35 ANGSTROMS). Strain: K12.
[12]	"Biochemical and structural analysis of the molybdenum cofactor biosynthesis protein MobA." Guse A., Stevenson C.E., Kuper J., Buchanan G., Schwarz G., Giordano G., Magalon A., Mendel R.R., Lawson D.M., Palmer T. J. Biol. Chem. 278:25302-25307(2003) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.65 ANGSTROMS) OF MUTANTS ALA-19; LEU-22; ASN-101; ASP-180 AND ASP-182, MUTAGENESIS OF GLY-15; ARG-19; GLY-22; LYS-25; GLY-78; GLY-82; ASP-101; ARG-156; ASN-180 AND ASN-182. Strain: K12.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

L19201 Genomic DNA. Translation: AAB02992.1.
U00096 Genomic DNA. Translation: AAC76855.1.
AP009048 Genomic DNA. Translation: BAE77451.1.

PIR

S40803.

RefSeq

NP_418294.1. NC_000913.2.
YP_491592.1. NC_007779.1.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1E5K	X-ray	1.35	A	1-194	[»]
1FR9	X-ray	1.65	A	1-194	[»]
1FRW	X-ray	1.75	A	1-194	[»]
1H4C	X-ray	1.65	A	1-194	[»]
1H4D	X-ray	1.74	A	1-194	[»]
1H4E	X-ray	1.65	A	1-194	[»]
1HJJ	X-ray	1.65	A	1-194	[»]
1HJL	X-ray	2.00	A	1-194	[»]

ProteinModelPortal

P32173.

SMR

P32173. Positions 4-191.

ModBase

Search...

Protein-protein interaction databases

DIP

DIP-10233N.

IntAct

P32173. 10 interactions.

MINT

MINT-1232345.

STRING

511145.b3857.

Proteomic databases

PaxDb

P32173.

PRIDE

P32173.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

EnsemblBacteria

AAC76855; AAC76855; b3857.
BAE77451; BAE77451; BAE77451.

GeneID

12931711.
948349.

KEGG

ecj:Y75_p3328.
eco:b3857.

PATRIC

32123211. VBIEscCol129921_3966.

Organism-specific databases

EchoBASE

EB1776.

EcoGene

EG11829. mobA.

Phylogenomic databases

eggNOG

COG0746.

HOGENOM

HOG000280423.

KO

K03752.

OMA

ACDEERE.

ProtClustDB

PRK00317.

Enzyme and pathway databases

BioCyc

EcoCyc:EG11829-MONOMER.
ECOL316407:JW3829-MONOMER.
MetaCyc:EG11829-MONOMER.

Gene expression databases

Genevestigator

P32173.

Family and domain databases

HAMAP

MF_00316. MobA.

InterPro

IPR025877. MobA-like_NTP_Trfase_dom.
IPR013482. Molybde_CF_guanTrfase.
[Graphical view]

Pfam

PF12804. NTP_transf_3. 1 hit.
[Graphical view]

TIGRFAMs

TIGR02665. molyb_mobA. 1 hit.

ProtoNet

Search...

Other

EvolutionaryTrace

P32173.

Entry information

Entry name

MOBA_ECOLI

Accession

Primary (citable) accession number: P32173
Secondary accession number(s): Q2M8F5, Q9LBV0

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1993
Last sequence update:	October 1, 1993
Last modified:	May 1, 2013
This is version 116 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program