Structure of PDB 4h44 Chain A

Receptor sequence

>4h44A (length=215) Species: 103690 (Nostoc sp. PCC 7120 = FACHB-418)

MANVYDWFEERLEIQAIAEDVTSKYVPPHVNIFYCLGGITLVCFLIQFAT
GFAMTFYYKPTVAEAYSSVQYIMNEVNFGWLIRSIHRWSASMMVLMMILH
VFRVYLTGGFKKPRELTWVSGVILAVITVSFGVTGYSLPWDQVGYWAVKI
VSGVPEAIPVVGVLISDLLRGGSSVGQATLTRYYSAHTFVLPWLIAVFML
FHFLMIRKQGISGPL

3D structure

• PDB: 4h44 Quinone-dependent proton transfer pathways in the photosynthetic cytochrome b6f complex
• Chain: A
• Resolution: 2.7 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): R207 I211
• Catalytic site (residue number reindexed from 1): R207 I211

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	peptide	A	N31 I32	N31 I32
BS02	HEM	A	Q47 G51 M54 Y58 R83 H86 R87 A90 T128 F131 G135 L138 P139 H187 P192	Q47 G51 M54 Y58 R83 H86 R87 A90 T128 F131 G135 L138 P139 H187 P192
BS03	HEM	A	Y34 G37 G38 T40 H100 V101 R103 V104 T117 W118 G121 M199 H202 I206 I211 S212	Y34 G37 G38 T40 H100 V101 R103 V104 T117 W118 G121 M199 H202 I206 I211 S212
BS04	HEM	A	V30 Y34 C35 G38 L41 F203 I206 R207 G210	V30 Y34 C35 G38 L41 F203 I206 R207 G210
BS05	CLA	A	Y105 A125	Y105 A125

Gene Ontology

Molecular Function

• GO:0009055 electron transfer activity
• GO:0016491 oxidoreductase activity
• GO:0045158 electron transporter, transferring electrons within cytochrome b6/f complex of photosystem II activity
• GO:0046872 metal ion binding

Biological Process

• GO:0015979 photosynthesis
• GO:0022904 respiratory electron transport chain

Cellular Component

• GO:0009579 thylakoid
• GO:0016020 membrane
• GO:0031676 plasma membrane-derived thylakoid membrane
• GO:0042651 thylakoid membrane

External links

• PDB: RCSB:4h44, PDBe:4h44, PDBj:4h44
• PDBsum: 4h44
• PubMed: 23440205
• UniProt: P0A384|CYB6_NOSS1 Cytochrome b6 (Gene Name=petB)