A second rhodopsin-like protein in Cyanophora paradoxa: Gene sequence and protein expression in a cell-free system

作者：Frassanito Anna Maria; Barsanti Laura; Passarelli Vincenzo; Evangelista Valtere; Gualtieri Paolo^*

来源：Journal of Photochemistry and Photobiology B: Biology , 2013, 125: 188-193.

DOI：10.1016/j.jphotobiol.2013.06.010

• Rhodopsin-like protein
• Cyanophora paradoxa
• CpR2
• Cell-free expression
• Absorption spectrum

Here we report the identification and expression of a second rhodopsin-like protein in the alga Cyanophora paradoxa (Glaucophyta), named Cyanophopsin_2. This new protein was identified due to a serendipity event, since the RACE reaction performed to complete the sequence of Cyanophopsin_1, (the first rhodopsin-like protein of C. paradoxa identified in 2009 by our group), amplified a 619 bp sequence corresponding to a portion of a new gene of the same protein family. The full sequence consists of 1175 bp consisting of 849 bp coding DNA sequence and 4 introns of 326 bp. The protein is characterized by an N-terminal region of 47 amino acids, followed by a region with 7 alpha-helices of 213 amino acids and a C-terminal region of 22 amino acids. This protein showed high identity with Cyanophopsin_1 and other rhodopsin-like proteins of Archea, Bacteria, Fungi and Algae. Cyanophosin_2 (CpR2) was expressed in a cell-free expression system, and characterized by means of absorption spectroscopy.

• 出版日期2013-8-5