P92947 · MDAR_ARATH

Function

function

Catalyzes the conversion of monodehydroascorbate (MDA) to ascorbate, oxidizing NADH in the process. Can also use 2,4,6-trinitrotoluene (TNT) and 1-chloro-2,4-dinitrobenzene (CDNB) as substrates, but not 1-chloro-4-nitrobenzene (CNB).

Miscellaneous

The use of alternative transcription starts causes dual targeting of the same mature MDAR protein to both mitochondria and chloroplast.

Catalytic activity

Cofactor

FAD (UniProtKB | Rhea| CHEBI:57692 )

Activity regulation

Redox regulation of the activity by thioredoxin TRXy1.

Biotechnology

The main mechanism for TNT toxicity in plants is the production of superoxide in the mitochondria by MDAR5 with TNT as a substrate. Inactivation of MDAR5 enhance TNT tolerance, thus enabling revegetation and remediation of explosives-contaminated sites.

Kinetics

KM SUBSTRATE pH TEMPERATURE[C] NOTES EVIDENCE
522 μM2,4,6-trinitrotoluene
4.1 μMmonodehydroascorbate
1254 μM1-chloro-2,4-dinitrobenzene
Vmax pH TEMPERATURE[C] NOTES EVIDENCE
0.143 mmol/min/mgwith 2,4,6-trinitrotoluene as substrate
190 mmol/min/mgwith monodehydroascorbate as substrate
0.96 mmol/min/mgwith 1-chloro-2,4-dinitrobenzene as substrate

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site68-71FAD (UniProtKB | ChEBI)
Binding site95FAD (UniProtKB | ChEBI)
Binding site102FAD (UniProtKB | ChEBI)
Binding site107FAD (UniProtKB | ChEBI)
Binding site201-202FAD (UniProtKB | ChEBI)
Binding site224-230NAD+ (UniProtKB | ChEBI)
Binding site226-230NADP+ (UniProtKB | ChEBI)
Binding site248NAD+ (UniProtKB | ChEBI)
Binding site254NAD+ (UniProtKB | ChEBI)
Binding site254NADP+ (UniProtKB | ChEBI)
Binding site313NAD+ (UniProtKB | ChEBI)
Binding site313NADP+ (UniProtKB | ChEBI)
Binding site351FAD (UniProtKB | ChEBI)
Binding site367-368NAD+ (UniProtKB | ChEBI)
Binding site367-368NADP+ (UniProtKB | ChEBI)
Binding site369FAD (UniProtKB | ChEBI)
Binding site373L-ascorbate (UniProtKB | ChEBI)
Binding site398FAD (UniProtKB | ChEBI)
Binding site398NAD+ (UniProtKB | ChEBI)
Binding site398NADP+ (UniProtKB | ChEBI)
Binding site400L-ascorbate (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentchloroplast
Cellular Componentchloroplast stroma
Cellular Componentmitochondrion
Cellular Componentnucleus
Cellular Componentstromule
Molecular FunctionATP binding
Molecular Functionmonodehydroascorbate reductase (NADH) activity
Biological Processresponse to cold

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Monodehydroascorbate reductase, chloroplastic/mitochondrial
  • EC number
  • Alternative names
    • Monodehydroascorbate reductase 5, mitochondrial
      (AtMDAR5
      )
    • Monodehydroascorbate reductase 6, chloroplastic
      (AtMDAR6
      )

Gene names

    • Name
      MDAR5
    • Synonyms
      MDAR6
      , MDHAR6
      , PMDAR-L
      , PMDAR-S
    • ORF names
      T12P18.4
    • Ordered locus names
      At1g63940

Organism names

  • Taxonomic identifier
  • Strain
    • cv. Columbia
  • Taxonomic lineage
    Eukaryota > Viridiplantae > Streptophyta > Embryophyta > Tracheophyta > Spermatophyta > Magnoliopsida > eudicotyledons > Gunneridae > Pentapetalae > rosids > malvids > Brassicales > Brassicaceae > Camelineae > Arabidopsis

Accessions

  • Primary accession
    P92947
  • Secondary accessions
    • Q94CE2
    • Q9CAK5

Proteomes

Organism-specific databases

Genome annotation databases

Subcellular Location

Keywords

Phenotypes & Variants

Disruption phenotype

No visible phenotype, but enhanced 2,4,6-trinitrotoluene (TNT) tolerance.

Variants

We now provide the "Disease & Variants" viewer in its own tab.

The viewer provides 29 variants from UniProt as well as other sources including ClinVar and dbSNP.

Go to variant viewer

PTM/Processing

Features

Showing features for transit peptide, chain.

TypeIDPosition(s)Description
Transit peptide1-51Chloroplast and mitochondrion
ChainPRO_000001862152-493Monodehydroascorbate reductase, chloroplastic/mitochondrial

Proteomic databases

PTM databases

Expression

Gene expression databases

Interaction

Subunit

Interacts in vitro with TRXy.

Protein-protein interaction databases

Structure

Family & Domains

Sequence similarities

Keywords

Phylogenomic databases

Family and domain databases

Sequence & Isoform

Align isoforms (2)
  • Sequence status
    Complete
  • Sequence processing
    The displayed sequence is further processed into a mature form.

This entry describes 2 isoforms produced by Alternative promoter usage.

P92947-1

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.

  • Name
    MDAR5
  • Synonyms
    PMDAR-L
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Length
    493
  • Mass (Da)
    53,302
  • Last updated
    2004-07-19 v3
  • Checksum
    44FBF0DE65DA89D7
MSAVRRVMALASTTLPTKSGLSLWCPSSPSLARRFPARFSPIGSRIASRSLVTASFANENREFVIVGGGNAAGYAARTFVENGMADGRLCIVTKEAYAPYERPALTKAYLFPPEKKPARLPGFHTCVGGGGERQTPDWYKEKGIEVIYEDPVAGADFEKQTLTTDAGKQLKYGSLIIATGCTASRFPDKIGGHLPGVHYIREVADADSLIASLGKAKKIVIVGGGYIGMEVAAAAVAWNLDTTIVFPEDQLLQRLFTPSLAQKYEELYRQNGVKFVKGASINNLEAGSDGRVSAVKLADGSTIEADTVVIGIGAKPAIGPFETLAMNKSIGGIQVDGLFRTSTPGIFAIGDVAAFPLKIYDRMTRVEHVDHARRSAQHCVKSLLTAHTDTYDYLPYFYSRVFEYEGSPRKVWWQFFGDNVGETVEVGNFDPKIATFWIESGRLKGVLVESGSPEEFQLLPKLARSQPLVDKAKLASASSVEEALEIAQAALQS

P92947-2

  • Name
    MDAR6
  • Synonyms
    PMDAR-S
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical
    • 1-7: Missing

Computationally mapped potential isoform sequences

There are 2 potential isoforms mapped to this entry

View all
EntryEntry nameGene nameLength
F4I576F4I576_ARATHMDAR6482
F4I577F4I577_ARATHMDAR6416

Features

Showing features for alternative sequence, sequence conflict.

TypeIDPosition(s)Description
Alternative sequenceVSP_0113601-7in isoform MDAR6
Sequence conflict109in Ref. 1; BAA12349

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
D84417
EMBL· GenBank· DDBJ
BAA12349.2
EMBL· GenBank· DDBJ
mRNA
AC010852
EMBL· GenBank· DDBJ
AAG52455.1
EMBL· GenBank· DDBJ
Genomic DNA
CP002684
EMBL· GenBank· DDBJ
AEE34168.1
EMBL· GenBank· DDBJ
Genomic DNA
CP002684
EMBL· GenBank· DDBJ
AEE34171.1
EMBL· GenBank· DDBJ
Genomic DNA
AY034934
EMBL· GenBank· DDBJ
AAK59441.1
EMBL· GenBank· DDBJ
mRNA
AY142572
EMBL· GenBank· DDBJ
AAN13141.1
EMBL· GenBank· DDBJ
mRNA
BT000667
EMBL· GenBank· DDBJ
AAN31814.1
EMBL· GenBank· DDBJ
mRNA

Genome annotation databases

Similar Proteins

Disclaimer

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