Structure of PDB 8bq6 Chain BC

Receptor sequence

>8bq6BC (length=387) Species: 3702 (Arabidopsis thaliana)

TIRNQRFSLLKQPISSTLNQHLVDYPTPSNLSYWWGFGSLAGICLVIQIV
TGVFLAMHYTPHVDLAFNSVEHIMRDVEGGWLLRYMHANGASMFFIVVYL
HIFRGLYYASYSSPREFVWCLGVVIFLLMIVTAFIGYVLPWGQMSFWGAT
VITSLASAIPVVGDTIVTWLWGGFSVDNATLNRFFSLHYLLPFILVGASL
LHLAALHQYGSNNPLGVHSEMDKIAFYPYFYVKDLVGWVAFAIFFSIWIF
YAPNVLGHPDNYIPANPMSTPPHIVPEWYFLPIYAILRSIPDKAGGVAAI
ALVFICLLALPFFKSMYVRSSSFRPIYQGMFWLLLADCLLLGWIGCQPVE
APFVTIGQISSLVFFLFFAITPILGRVGRGIPNSYTD

3D structure

• PDB: 8bq6 Cryo-EM structure of the respiratory I + III 2 supercomplex from Arabidopsis thaliana at 2 angstrom resolution.
• Chain: BC
• Resolution: 2.8 Å

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	BC	W36 G39 A42 F95 H102 I103 R105 S111 G123 I126 H203 L207 S212 N213	W35 G38 A41 F94 H101 I102 R104 S110 G122 I125 H202 L206 S211 N212
BS02	HEM	BC	Q49 G53 R85 H88 T133 A134 G137 L140 P141 H189 Y190 P193	Q48 G52 R84 H87 T132 A133 G136 L139 P140 H188 Y189 P192
BS03	UQ5	BC	L23 S40 L46 V197 S200 L201 H208 F227	L22 S39 L45 V196 S199 L200 H207 F226
BS04	UQ7	BC	V132 G149 V152 I153 L188 V276 P277 F281 Y285	V131 G148 V151 I152 L187 V275 P276 F280 Y284

Gene Ontology

Molecular Function

• GO:0008121 ubiquinol-cytochrome-c reductase activity
• GO:0009055 electron transfer activity
• GO:0016491 oxidoreductase activity
• GO:0046872 metal ion binding

Biological Process

• GO:0006122 mitochondrial electron transport, ubiquinol to cytochrome c
• GO:0022904 respiratory electron transport chain
• GO:1902600 proton transmembrane transport

Cellular Component

• GO:0005739 mitochondrion
• GO:0005743 mitochondrial inner membrane
• GO:0016020 membrane
• GO:0045275 respiratory chain complex III

External links

• PDB: RCSB:8bq6, PDBe:8bq6, PDBj:8bq6
• PDBsum: 8bq6
• PubMed: 36585502
• UniProt: P42792|CYB_ARATH Cytochrome b (Gene Name=MT-CYB)