Related Experiment Video
Updated: Aug 9, 2026

In Vitro Reconstitution of Light-harvesting Complexes of Plants and Green Algae
Published on: October 10, 2014
Spectroscopic characterization of plastocyanin from hornwort
Abstract:
Plastocyanin isolated from an aquatic higher plant, Ceratophyllum demersum L. (hornwort), has been characterized by electronic absorption, circular dichroism (CD), and electron paramagnetic resonance (EPR) spectroscopies. The visible absorption, CD, and EPR spectra of hornwort plastocyanin indicated a complete similarity of blue copper center to those of terrestrial higher plants and algae. However, the ultraviolet absorption spectrum of hornwort plastocyanin exhibited a lower tyrosine (Tyr) and a higher phenylalanine (Phe) content of the protein comparing with other plastocyanins. The ratio of Phe/Tyr residues was estimated to be 9 by amino acid analysis. The hornwort plastocyanin resembles in amino acid composition terrestrial higher plant plastocyanins rather than alga plastocyanins but is peculiar in the content of Phe and Tyr residues.
Related Concept Videos
Anatomy of Chloroplasts
Photosystem II
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
The Photochemical Reaction Center
The Antenna Complex
Photosystems
Functioning of Photosystems
Photosystems contain many pigment molecules, such as chlorophylls and carotenoids, arranged in a particular organization across two domains — the antenna complex and the reaction center. The main aim of the pigment molecules...

