caa a22 4500 445318058 CHVBK 20180317142653.0 cr unu---uuuuu 170323e20110201xx s 000 0 eng 10.1007/s10126-010-9273-3 doi (NATIONALLICENCE)springer-10.1007/s10126-010-9273-3 Sulfide:quinone Oxidoreductase from Echiuran Worm Urechis unicinctus [Elektronische Daten] [Yu-Bin Ma, Zhi-Feng Zhang, Ming-Yu Shao, Kyoung-Ho Kang, Zhi Tan, Jin-Long Li] Sulfide is a natural, widely distributed, poisonous substance, and sulfide:quinone oxidoreductase (SQR) has been identified to be responsible for the initial oxidation of sulfide in mitochondria. In this study, full-length SQR cDNA was cloned from the echiuran worm Urechis unicinctus, a benthic organism living in marine sediments. The protein consisted of 451 amino acids with a theoretical pI of 8.98 and molecular weight of 50.5kDa. Subsequently, the SQR mRNA expression in different tissues was assessed by real-time reverse transcription and polymerase chain reaction and showed that the highest expression was in midgut, followed by anal sacs and coelomic fluid cells, and then body wall and hindgut. Furthermore, activated SQR was obtained by dilution refolding of recombinant SQR expression in E. coli, and the refolded product showed optimal activity at 37°C and pH 8.5 and K m for ubiquinone and sulfide at 15.6µM and 40.3µM, respectively. EDTA and GSH had an activating effect on refolded SQR, while Zn2+ caused decreased activity. Western blot showed that SQR in vivo was located in mitochondria and was ∼10kDa heavier than the recombinant protein. In addition, SQR, detected by immunohistochemistry, was mainly located in the epithelium of all tissues examined. Ultrastructural observations of these tissues' epithelium by transmission electron microscopy provided indirect cytological evidence for its mitochondrial location. Interesting aspects of the U. unicinctus SQR amino acid sequence, its catalytic mechanism, and the different roles of these tissues in sulfide metabolic adaptation are also discussed. Springer Science+Business Media, LLC, 2010 Mitochondria nationallicence Sulfide:quinone oxidoreductase (SQR) nationallicence Sulfide nationallicence Urechis unicinctus nationallicence Ma Yu-Bin Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut Zhang Zhi-Feng Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut Shao Ming-Yu Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut Kang Kyoung-Ho Department of Aquaculture, Chonnam National University, 550749, Yeosu, South Korea aut Tan Zhi Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut Li Jin-Long Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut Marine Biotechnology Springer-Verlag 13/1(2011-02-01), 93-107 1436-2228 13:1<93 2011 13 10126 https://doi.org/10.1007/s10126-010-9273-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10126-010-9273-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ma Yu-Bin Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut NATIONALLICENCE 700 1- Zhang Zhi-Feng Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut NATIONALLICENCE 700 1- Shao Ming-Yu Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut NATIONALLICENCE 700 1- Kang Kyoung-Ho Department of Aquaculture, Chonnam National University, 550749, Yeosu, South Korea aut NATIONALLICENCE 700 1- Tan Zhi Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut NATIONALLICENCE 700 1- Li Jin-Long Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Ocean University of China, 266003, Qingdao, China aut NATIONALLICENCE 773 0- Marine Biotechnology Springer-Verlag 13/1(2011-02-01), 93-107 1436-2228 13:1<93 2011 13 10126 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer