Structure of PDB 3ir7 Chain A

Receptor sequence

>3ir7A (length=1242) Species: 83333 (Escherichia coli K-12)

SKFLDRFFKQKGETFADGHGQLLNTNRDWEDGYRQRWQHDKIVRSTHGVN
CTGSCSWKIYVKNGLVTWETQQTDYPRTRPDLPNHEPRGCPSGASYSWYL
YSANRLKYPMMRKRLMKMWREAKALHSDPVEAWASIIEDADKAKSFKQAR
GRGGFVRSSWQEVNELIAASNVYTIKNYGPDRVAGFSPIPAMSMVSYASG
ARYLSLIGGTCLSFYDWYCDLPPASPQTWGEQTDVPESADWYNSSYIIAW
GSNVPQTRTPDAHFFTEVRYKGTKTVAVTPDYAEIAKLCDLWLAPKQGTD
AAMALAMGHVMLREFHLDNPSQYFTDYVRRYTDMPMLVMLEERDGYYAAG
RMLRAADLVDALGQENNPEWKTVAFNTNGEMVAPNGSIGFRWGEKGKWNL
EQRDGKTGEETELQLSLLGSQDEIAEVGFPYFGGDGTEHFNKVELENVLL
HKLPVKRLQLADGSTALVTTVYDLTLANYGLERGLNDVNCATSYDDVKAY
TPAWAEQITGVSRSQIIRIAREFADNADKTHGRSMIIVGAGLNHWYHLDM
NYRGLINMLIFCGCVGQSGGGWAHYVGQEKLRPQTGWQPLAFALDWQRPA
RHMNSTSYFYNHSSQWRYETVTAEELLSPMADKSRYTGHLIDFNVRAERM
GWLPSAPQLGTNPLTIAGEAEKAGMNPVDYTVKSLKEGSIRFAAEQPENG
KNHPRNLFIWRSNLLGSSGKGHEFMLKYLLGTEHGIQGKDLGQQGGVKPE
EVDWQDNGLEGKLDLVVTLDFRLSSTCLYSDIILPTATWYEKDDMNTSDM
HPFIHPLSAAVDPAWEAKSDWEIYKAIAKKFSEVCVGHLGKETDIVTLPI
QHDSAAELAQPLDVKDWKKGECDLIPGKTAPHIMVVERDYPATYERFTSI
GPLMEKIGNGGKGIAWNTQSEMDLLRKLNYTKAEGPAKGQPMLNTAIDAA
EMILTLAPETNGQVAVKAWAALSEFTGRDHTHLALNKEDEKIRFRDIQAQ
PRKIISSPTWSGLEDEHVSYNAGYTNVHELIPWRTLSGRQQLYQDHQWMR
DFGESLLVYRPPIDTRSVKEVIGQKSNGNQEKALNFLTPHQKWGIHSTYS
DNLLMLTLGRGGPVVWLSEADAKDLGIADNDWIEVFNSNGALTARAVVSQ
RVPAGMTMMYHAQERIVNLPGSEITQQRGGIHNSVTRITPKPTHMIGGYA
HLAYGFNYYGTVGSNRDEFVVVRKMKNIDWLDGEGNDQVQES

3D structure

• PDB: 3ir7 Protein crystallography reveals a role for the FS0 cluster of Escherichia coli nitrate reductase A (NarGHI) in enzyme maturation.
• Chain: A
• Resolution: 2.5 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): S94 P190 W219 Y220 P224 Q580
• Catalytic site (residue number reindexed from 1): S92 P188 W217 Y218 P222 Q578
• 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	MD1	A	Y220 D222 H546 R713 S714 N715 S719 S720 K722 L771 D772 F773 R774 T788 W791 K794 D822 T1090 H1092 H1098 S1099 T1100 H1163 N1185 N1217	Y218 D220 H544 R711 S712 N713 S717 S718 K720 L769 D770 F771 R772 T786 W789 K792 D820 T1088 H1090 H1096 S1097 T1098 H1161 N1183 N1215
BS02	MD1	A	D222 G253 N255 Q258 T259 R260 V280 P282 D283 Q299 D302 G541 A542 G543 L544 W547 V578 G579 P1091 H1092 Q1093 G1096 I1097 H1098 R1218	D220 G251 N253 Q256 T257 R258 V278 P280 D281 Q297 D300 G539 A540 G541 L542 W545 V576 G577 P1089 H1090 Q1091 G1094 I1095 H1096 R1216
BS03	SF4	A	H49 C53 G55 C57 W59 G91 C92 G95 P262	H47 C51 G53 C55 W57 G89 C90 G93 P260
BS04	6MO	A	D222 G579	D220 G577

Gene Ontology

Molecular Function

• GO:0005515 protein binding
• GO:0008940 nitrate reductase activity
• GO:0009055 electron transfer activity
• GO:0016491 oxidoreductase activity
• GO:0043546 molybdopterin cofactor binding
• GO:0046872 metal ion binding
• GO:0051539 4 iron, 4 sulfur cluster 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
• GO:0045333 cellular respiration

Cellular Component

• GO:0005886 plasma membrane
• GO:0009325 nitrate reductase complex
• GO:0016020 membrane
• GO:0044799 NarGHI complex
• GO:1990204 oxidoreductase complex

External links

• PDB: RCSB:3ir7, PDBe:3ir7, PDBj:3ir7
• PDBsum: 3ir7
• PubMed: 20053990
• UniProt: P09152|NARG_ECOLI Respiratory nitrate reductase 1 alpha chain (Gene Name=narG)