PDBsum entry 5v2c

Electron transport, photosynthesis

PDB id: 5v2c

Contents

Protein chains

334 a.a.

504 a.a.

451 a.a.

342 a.a.

81 a.a.

34 a.a.

65 a.a.

38 a.a.

39 a.a.

37 a.a.

37 a.a.

34 a.a.

245 a.a.

30 a.a.

97 a.a.

137 a.a.

29 a.a.

40 a.a.

62 a.a.

32 a.a.

35 a.a.

Ligands

OEX ×2

BCT ×3

CLA ×70

PHO ×4

BCR ×22

PL9 ×4

SQD ×11

LMG ×14

GOL ×60

LMT ×18

LHG

PG4

PGE

P6G

EDO ×22

HTG ×24

1PE ×7

DGD ×10

HEM ×2

HEC ×2

2PE

PE8

Metals

FE2 ×2

_CL

_CA

_MG

Waters ×3789

References listed in PDB file

Key reference

• Title: Chlorophyll a with a farnesyl tail in thermophilic cyanobacteria.
• Authors: J.M.Wiwczar, A.M.Lafountain, J.Wang, H.A.Frank, G.W.Brudvig.
• Ref.: Photosynth Res, 2017, 134, 175-182.
• PubMed id: 28741056

Abstract

Photosystem II (PSII) of oxygenic photosynthetic organisms normally contains exclusively chlorophyll a (Chl a) as its major light-harvesting pigment. Chl a canonically consists of the chlorin headgroup with a 20-carbon, 4-isoprene unit, phytyl tail. We have examined the 1.9 Å crystal structure of PSII from thermophilic cyanobacteria reported by Shen and coworkers in 2012 (PDB accession of 3ARC/3WU2). A newly refined electron density map from this structure, presented here, reveals that some assignments of the cofactors may be different from those modeled in the 3ARC/3WU2 structure, including a specific Chl a that appears to have a truncated tail by one isoprene unit. We provide experimental evidence using high-performance liquid chromatography and mass spectrometry for a small population of Chl a esterified to a 15-carbon farnesyl tail in PSII of thermophilic cyanobacteria.