Structure of PDB 1siw Chain C

Receptor sequence

>1siwC (length=219) Species: 562 (Escherichia coli)

MQFLNMFFFDIYPYIAGAVFLIGSWLRYDYGQYTWRAASSQMLDRKGMNL
ASNLFHIGILGIFVGHFFGMLTAWLPIEVKQKMAMFAGGASGVLCLIGGV
LLLKRRLFSPRVRATTTGADILILSLLVIQCALGLLTIPFSAQHMDGSEM
MKLVGWAQSVVTFHGGASQHLDGVAFIFRLHLVLGMTLFLLFPFSRLIHI
WSVPVEYLTRKYQLVRARH

3D structure

• PDB: 1siw The catalytic subunit of Escherichia coli nitrate reductase A contains a novel [4Fe-4S] cluster with a high-spin ground state
• Chain: C
• Resolution: 2.2 Å

Enzymatic activity

• Enzyme Commision number: 1.7.5.1: nitrate reductase (quinone).

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	HEM	C	S39 S40 Q41 M48 F55 H56 R112 R202 H205 I206	S39 S40 Q41 M48 F55 H56 R106 R196 H199 I200
BS02	HEM	C	I59 I62 H66 A90 G94 Q136 C137 G140 M156 L159 H187 L188 G191 F195	I59 I62 H66 A84 G88 Q130 C131 G134 M150 L153 H181 L182 G185 F189

Gene Ontology

Molecular Function

• GO:0008940 nitrate reductase activity
• GO:0009055 electron transfer activity
• GO:0016491 oxidoreductase activity
• GO:0020037 heme binding
• GO:0046872 metal ion binding
• GO:0160182 nitrate reductase (quinone) activity

Biological Process

• GO:0009061 anaerobic respiration
• GO:0019645 anaerobic electron transport chain
• GO:0042126 nitrate metabolic process
• GO:0042128 nitrate assimilation

Cellular Component

• GO:0005886 plasma membrane
• GO:0009325 nitrate reductase complex
• GO:0016020 membrane
• GO:0044799 NarGHI complex

External links

• PDB: RCSB:1siw, PDBe:1siw, PDBj:1siw
• PDBsum: 1siw
• PubMed: 15122898
• UniProt: P11350|NARI_ECOLI Respiratory nitrate reductase 1 gamma chain (Gene Name=narI)