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Chlorophyll a with a farnesyl tail in thermophilic cyanobacteria.

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.

SUBMITTER: Wiwczar JM

PROVIDER: S-EPMC5832022 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Chlorophyll a with a farnesyl tail in thermophilic cyanobacteria.

Wiwczar Jessica M JM LaFountain Amy M AM Wang Jimin J Frank Harry A HA Brudvig Gary W GW

Photosynthesis research 20170724 2

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 assi ...[more]

PMID: 28741056

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