Chlorophylls as primary electron acceptors in reaction centers

Michael Gorka, Patrick Landry, Elijah Gruszecki, Amanda Malnati, Divya Kaur, Art van der Est, John H. Golbeck, K. V. Lakshmi

Research output: Chapter in Book/Report/Conference proceedingChapter

2 Scopus citations

Abstract

Photosynthetic Reaction Centers (RCs) can be considered blueprints for highly efficient energy transfer. Embedded with an array of cofactors, including (bacterio)chlorophyll ((B)Chl) and (B)pheophytin ((B)Pheo) molecules, RCs function with a high quantum yield that spans a wide spectral range. Understanding the principles that underlie their function can influence the design of the next generation of artificial photosynthetic devices. We are particularly interested in the factors that influence the early stages of light-driven charge separation in RCs. With the recent publication of several highly anticipated RC structures and advanced computational methods available, it is possible to probe both the geometric and electronic structures of an array of RCs. In this chapter, we review the electronic and geometric structures of the (B)Chl and (B)Pheo primary electron acceptors from fiveRCs, comprising both Type I and Type II RCs and representing both heterodimeric and homodimeric systems. We showcase the dimeric A0•- state of Type I RCs, whereby the unpaired electron is delocalized, to various extents, over two (B)Chl molecules (B)Chl2 and (B)Chl3. This delocalization is controlled by several factors, including the structure of the (B)Chls, interactions with the surrounding protein matrix, and the orientation and distances of the cofactors themselves. In contrast, the primary acceptors of Type II RCs are entirely monomeric, with electron density residing solely on the (B)Pheo. We compare the natural design of the primary acceptors of the Type I and Type II RCs from both an evolutionary and application based perspective.

Original languageEnglish (US)
Title of host publicationPhotosynthesis
Subtitle of host publicationFrom Plants to Nanomaterials
PublisherElsevier
Pages197-237
Number of pages41
ISBN (Electronic)9780323983914
ISBN (Print)9780323985703
DOIs
StatePublished - Jan 1 2023

All Science Journal Classification (ASJC) codes

  • General Agricultural and Biological Sciences

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