Isolation and characterization of proteorhodopsin homologue from Yellow Sea of Korea

• Published in: Genes & genomics Vol. 38; no. 5; pp. 447 - 452
• Main Authors: Kim, Sehwan, Kimleng, Chuon, Jang, Hyejin, Sohn, Hyogon, Kim, Gwan-jib, Lee, Gap Ryol, Kim, Kun-Soo, Choi, Ahreum, Jung, Kwang-Hwan
• Format: Journal Article
• Language: English
• Published: Seoul The Genetics Society of Korea 01.05.2016; 한국유전학회
• Subjects: absorption; Animal Genetics and Genomics; anions; Biomedical and Life Sciences; cations; DNA; energy; Human Genetics; Korean Peninsula; Life Sciences; metagenomics; Microbial Genetics and Genomics; Plant Genetics and Genomics; polymerase chain reaction; proton pump; protons; Research Article; rhodopsin; sodium; swamps; Yellow Sea; 생물학; Yellow Sea; Korean Peninsula; Proteorhodopsin; Chimeric expression system; Membrane protein; Microbial rhodopsin; Proton pumping
• ISSN: 1976-9571; 2092-9293
• DOI: 10.1007/s13258-016-0392-8

Many organisms use proton pump to earn energy for living. Some proton pumps start to work by light and one of the famous proteins are called proteorhodopsin (PR). From recent study it used not only protons but also mono-valent cations, divalent cations, or mono-valent anions during pumping activity. The goal of this study is to find new types of proton pumping proteins in the surface of the ocean. Metagenome samples were collected from the beach in Taean-gun and Incheon (Kkotji beach (36°30′0′′N, 126°19′56′′E), Kkotji mud (36°30′8′′N, 126°19′60′′E), Duegi beach (36°31′6′′N, 126°19′39′′E), Sorae salt pond (37°24′25′′N, 126°44′41′′E), swamp (37°24′59′′N, 126°44′54′′E) and reservoir (37°24′39′′N, 126°45′5′′E) in West Sea of Korea. Genomic DNA of each sample was isolated and used for PCR with specific primers for PR and sodium pumping rhodopsin. As a result, we obtained an unidentified PR in Duegi beach sample. The unidentified PR was expressed with chimeric expression system. It has 528 nm absorption maximum at pH 7. By the light differential spectrum measurement, putative M and O photo-intermediates were detected at around 400 and 600 nm, respectively. Similar to GPR, it has light driven outward proton transfer activity.