5OOK

Structure of A. marina Phycocyanin contains overlapping isoforms

5OOK の概要

• エントリーDOI: 10.2210/pdb5ook/pdb
• 分子名称: Phycocyanin, alpha subunit, Phycocyanin, beta subunit, PHYCOCYANOBILIN, ... (5 entities in total)
• 機能のキーワード: models, phycobilisome, phycocyanin, a. marina, photosynthesis
• 由来する生物種: Acaryochloris marina; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 38256.02

構造登録者

Bar-Zvi, S.,Lahav, A.,Blankenship, E.R.,Adir, N. (登録日: 2017-08-08, 公開日: 2018-06-20, 最終更新日: 2024-01-17)

主引用文献

Bar-Zvi, S.,Lahav, A.,Harris, D.,Niedzwiedzki, D.M.,Blankenship, R.E.,Adir, N.
Structural heterogeneity leads to functional homogeneity in A. marina phycocyanin.
Biochim. Biophys. Acta, 1859:544-553, 2018

PubMed Abstract: The major light harvesting antenna in all cyanobacterial species is the phycobilisome (PBS). The smallest PBS identified to date is that of Acaryochloris marina (A. marina), composed of a single four-hexamer rod. We have determined the crystal structure of phycocyanin (AmPC), the major component of the A. marina PBS (AmPBS) to 2.1 Å. The basic unit of the AmPC is a heterodimer of two related subunits (α and β), and we show that the asymmetric unit contains a superposition of two α and two β isoforms, the products of the simultaneous expression of different genes. This is the first time to our knowledge that isolated proteins crystallized with such identifiable heterogeneity. We believe that the presence of the different isoforms allows the AmPBS to have a significant bathochromic shift in its fluorescence emission spectrum, allowing, in the total absence of allophycocyanin, a better overlap with absorption of the chlorophyll d-containing reaction centers. We show that this bathochromic shift exists in intact AmPBS as well as in its disassembled components, thus suggesting that AmPC can efficiently serve as the AmPBS terminal emitter.

PubMed: 29704497
DOI: 10.1016/j.bbabio.2018.04.007

実験手法

X-RAY DIFFRACTION (2.1 Å)