O33465 (METH_PSEPU) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Methionine synthase
EC=2.1.1.13

Alternative name(s):
5-methyltetrahydrofolate--homocysteine methyltransferase
Methionine synthase, vitamin-B12 dependent
Short name=MS

Gene names

Name:

metH

Organism

Pseudomonas putida (Arthrobacter siderocapsulatus)

Taxonomic identifier

303 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Pseudomonadales › Pseudomonadaceae › Pseudomonas › Pseudomonas putida group

Protein attributes

Sequence length	607 AA.
Sequence status	Fragment.
Protein existence	Inferred from homology

General annotation (Comments)

Function	Catalyzes the transfer of a methyl group from methyl-cobalamin to homocysteine, yielding enzyme-bound cob(I)alamin and methionine. Subsequently, remethylates the cofactor using methyltetrahydrofolate By similarity.
Catalytic activity	5-methyltetrahydrofolate + L-homocysteine = tetrahydrofolate + L-methionine.
Cofactor	Cobalamin By similarity. Binds 1 zinc ion per subunit Potential.
Pathway	Amino-acid biosynthesis; L-methionine biosynthesis via de novo pathway; L-methionine from L-homocysteine (MetH route): step 1/1.
Domain	Modular enzyme with four functionally distinct domains. The isolated Hcy-binding domain catalyzes methyl transfer from free methylcobalamin to homocysteine. The Hcy-binding domain in association with the pterin-binding domain catalyzes the methylation of cob(I)alamin by methyltetrahydrofolate and the methylation of homocysteine. The B12-binding domain binds the cofactor. The AdoMet activation domain binds S-adenosyl-L-methionine. Under aerobic conditions cob(I)alamin can be converted to inactive cob(II)alamin. Reductive methylation by S-adenosyl-L-methionine and flavodoxin regenerates methylcobalamin By similarity.
Miscellaneous	L-homocysteine is bound via the zinc atom By similarity.
Sequence similarities	Belongs to the vitamin-B12 dependent methionine synthase family. Contains 1 Hcy-binding domain. Contains 1 pterin-binding domain.
Caution	Ser-314 is present instead of the conserved Cys which is expected to be a zinc-binding residue.

Ontologies

Keywords
Biological process	Amino-acid biosynthesis Methionine biosynthesis
Ligand	Cobalamin Cobalt Metal-binding S-adenosyl-L-methionine Zinc
Molecular function	Methyltransferase Transferase
Gene Ontology (GO)
Biological_process	pteridine-containing compound metabolic process Inferred from electronic annotation. Source: InterPro
Molecular_function	cobalamin binding Inferred from electronic annotation. Source: UniProtKB-KW homocysteine S-methyltransferase activity Inferred from electronic annotation. Source: InterPro methionine synthase activity Inferred from electronic annotation. Source: EC zinc ion 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 – ›607	›607	Methionine synthase		PRO_0000204535
Regions
	Domain	8 – 328	321	Hcy-binding
	Domain	359 – ›607	›249	Pterin-binding
Sites
	Metal binding	250	1	Zinc Potential
	Metal binding	313	1	Zinc Potential
Experimental info
	Non-terminal residue	607	1

Sequences

	Sequence		Length	Mass (Da)
	O33465 [UniParc]. Last modified January 1, 1998. Version 1. Checksum: BB7743CC28A922B3	FASTA	607	65,840
	10 20 30 40 50 60 MSDRSARLQA LQNALKERIL ILDGGMGTMI QSYRLEEHDY RGTRFADWPS DVKGNNDLLL 70 80 90 100 110 120 LSRPDVIAAI EKAYLDAGAD ILETNTFNAT QISQADYGME SLVYELNVEG ARIARQVADA 130 140 150 160 170 180 KTLETPDKPR FVAGVLGPTS RTCSISPDVN DPGYRNVTFD ELVENYIEAT RGLIEGGADL 190 200 210 220 230 240 ILIETIFDTL NAKAAIFAVQ QVFEEDAVEL PIMISGTITD ASGRTLSGQT TEAFWNSVRH 250 260 270 280 290 300 AKPISVGLNC ALGAKDLRPY LEELSTKADT HVSAHPNAGL PNAFGEYDET PAEMAAVVEE 310 320 330 340 350 360 FAASGFLNII GGCSGTTPGH IQAIAEAVAK YKPREIPEIA KACRLSGLEP FTIDGQSLFV 370 380 390 400 410 420 NVGERTNITG SAKFARLIRE ENYTEALEVA LQQVEAGAQV IDINMDEGML DSQAAMVRFL 430 440 450 460 470 480 NMIAGEPDIS RVPIMIDSSK GEVIEAGLKC IQGKGIVNSI SMKEGVEQFK HHARLCKRYG 490 500 510 520 530 540 AAVVVMAFDE VGQADTAARK KEICKRSYDI LVNEVGFPPE DIIFDPNIFA VATGIEEHNN 550 560 570 580 590 600 YAVDFIEACA YIRDHLPHAL TSGGVSNVSF SFRGNNPVRE AIHSVFLFHA ISNGLTMGIV NAGLLEI

References

[1]	"Cis-trans isomerization of unsaturated fatty acids: cloning and sequencing of the cti gene from Pseudomonas putida P8." Holtwick R., Meinhardt F., Keweloh H. Appl. Environ. Microbiol. 63:4292-4297(1997) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: P8.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AJ000978 Genomic DNA. Translation: CAA04437.1.
3D structure databases
ProteinModelPortal	O33465.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Enzyme and pathway databases
UniPathway	UPA00051; UER00081.
Family and domain databases
Gene3D	3.20.20.20. 1 hit. 3.20.20.330. 1 hit.
InterPro	IPR011005. Dihydropteroate_synth-like. IPR011822. MetH. IPR000489. Pterin-binding. IPR003726. S_MeTrfase. [Graphical view]
PANTHER	PTHR21091:SF9. PTHR21091:SF9. 1 hit.
Pfam	PF00809. Pterin_bind. 1 hit. PF02574. S-methyl_trans. 1 hit. [Graphical view]
PIRSF	PIRSF000381. MetH. 1 hit.
SUPFAM	SSF51717. DHP_synth_like. 1 hit. SSF82282. S_methyl_trans. 1 hit.
PROSITE	PS50970. HCY. 1 hit. PS50972. PTERIN_BINDING. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

METH_PSEPU

Accession

Primary (citable) accession number: O33465

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 15, 1998
Last sequence update:	January 1, 1998
Last modified:	April 3, 2013
This is version 59 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program