Channelrhodopsin 1 is a 7-transmembrane protein that acts as a light-driven cation channel in eukaryotic green algae.

• Alternative names: Channelrhodopsin 1 (CaChR1)
• UniProt Number: G8HKA1
• Protein class: 7-transmembrane protein
• Organism: Chloromonas augustae (Chlamydomonas augustae)
• Sequence, explained: Wild-type sequence, N-terminal membrane-spanning domain (362 of 715 aa), 10× His-tag
• Affinity tags: His-tag (C-terminus)
• Expression host: Pichia pastoris (yeast)
• Buffer composition: 100 mM NaCl, 20 mM HEPES pH 7.4, 0.03% dodecyl maltoside (DDM)
• Purified via: PureCube Ni-NTA Agarose
• Absorbance: Extinction coefficient at 518 nm: 36000 M⁻¹cm⁻¹; Extinction coefficient at 590 nm: 54000 M⁻¹cm⁻¹
• Activity: Binding of ligand all-trans retinal, covalently bound to a lysine residue
• Evaluation of UV-VIS spectrum: absorbance ratio 280/518 nm = 2.2 (additional vibronic band at 480 nm)
• Function: Photoreceptor protein undergoing a photocycle, Retinal protein, light-driven cation channel

Due to Channelrhodopsin 1's covalently bound colored ligand, it is ideal for use as a control membrane protein, for example, for crystallization assays and biochemical/biophysical experiments. We provide channelrhodopsin 1 of high purity, purified from yeast as a His-tagged protein.