Aggregation of chlorophyll a induced in self-assembled membranes composed of DMPC and DHPC

Shogo Taguchi; Keishi Suga; Keita Hayashi; Makoto Yoshimoto; Yukihiro Okamoto; Hidemi Nakamura; Hiroshi Umakoshi

doi:10.1016/j.colsurfb.2018.12.008

Aggregation of chlorophyll a induced in self-assembled membranes composed of DMPC and DHPC

Colloids Surf B Biointerfaces. 2019 Mar 1:175:403-408. doi: 10.1016/j.colsurfb.2018.12.008. Epub 2018 Dec 5.

Authors

Shogo Taguchi¹, Keishi Suga², Keita Hayashi³, Makoto Yoshimoto⁴, Yukihiro Okamoto⁵, Hidemi Nakamura⁶, Hiroshi Umakoshi⁷

Affiliations

¹ Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan. Electronic address: shogo.taguchi@cheng.es.osaka-u.ac.jp.
² Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan. Electronic address: keishi.suga@cheng.es.osaka-u.ac.jp.
³ Department of Chemical Engineering, National Institute of Technology, Nara College, 22 Yata-cho, Yamatokoriyama, Nara 639-1080, Japan. Electronic address: hayashi@chem.nara-k.ac.jp.
⁴ Department of Applied Chemistry, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan. Electronic address: yosimoto@yamaguchi-u.ac.jp.
⁵ Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan. Electronic address: okamoto@cheng.es.osaka-u.ac.jp.
⁶ Department of Chemical Engineering, National Institute of Technology, Nara College, 22 Yata-cho, Yamatokoriyama, Nara 639-1080, Japan. Electronic address: nakamura@chem.nara-k.ac.jp.
⁷ Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan. Electronic address: umakoshi@cheng.es.osaka-u.ac.jp.

PMID: 30557742
DOI: 10.1016/j.colsurfb.2018.12.008

Abstract

The J-aggregate of chlorophyll a (Chla) functions as a light-harvesting antenna in natural systems. In this study, we employed the phospholipid membranes composed of longer-chain 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and shorter-chain 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC), as a platform to induce Chla aggregates. The DMPC/DHPC assembly at the mixing ratio (q) = 1.5 induced J-aggregates of Chla at 20 °C with a total lipid concentration of 20 mM. While, Chla aggregates were not observed in the membranes at q = ∞ (DMPC vesicles) and q = 0 (DHPC micelles). The surroundings Chla molecules in DMPC/DHPC at q = 1.5 were estimated to comprise a less polar environment, based on the deconvolution analysis of Soret band spectrum (400-440 nm). The photo-reduction activity of Chla J-aggregates was investigated in lower lipid concentration conditions.

Keywords: Chlorophyll a; J-aggregate; Light-harvesting; Lipid membrane; Localization; Photo-reduction.

MeSH terms

Cell Membrane / metabolism*
Chlorophyll A / chemistry*
Dimyristoylphosphatidylcholine / chemistry*
Lipid Bilayers / metabolism*
Micelles
Phospholipid Ethers / chemistry*

Substances

1,2-dihexadecyl-sn-glycero-3-phosphocholine
Lipid Bilayers
Micelles
Phospholipid Ethers
Dimyristoylphosphatidylcholine
Chlorophyll A