Article ID Journal Published Year Pages File Type
2058251 Marine Genomics 2011 7 Pages PDF
Abstract

Catalase (EC 1.11.1.6) is an important antioxidant enzyme that protects aerobic organisms against oxidative damage by degrading hydrogen peroxide to water and oxygen. In the present study, a catalase cDNA of peal oyster Pincatada fucata (designated as PoCAT) is cloned and characterized by expressed sequence tag (EST) and rapid amplification of cDNA ends (RACE) methods. PoCAT is 2428 bp long and consists of a 5′-UTR of 140 bp, an unusually long 3′-UTR of 749 bp, and an open reading frame (ORF) of 1539 bp. The ORF of PoCAT encodes a polypeptide of 512 amino acids with molecular weight of 58.1 kDa and the theoretical isoelectric point of 8.4. PoCAT shares 62.3–82.2% identity and 73.0–92.0% similarity to other catalase amino acid sequences. Sequence alignment indicates that PoCAT contains the proximal heme-ligand signature sequence (R351LFSYSDT358), the proximal active site signature (F61NRERIPERVVHAKGGGA78), and the three catalytic amino acid residues (His72, Asn145, and Tyr 355). PoCAT has two potential glycosylation sites (N436YS438 and N478FS480) and a peroxisome targeting signal (ASL). PoCAT mRNA was ubiquitously expressed in all detected tissues, and the expression level of PoCAT mRNA was higher in intestine and mantle. The expression profile analysis showed that the expression level of PoCAT mRNA in intestine was significantly up-regulated at 2, 4 and 12 h after Vibrio alginolyticus stimulation. These results demonstrated that PoCAT is a typical member of catalase family and might be involved in innate immune responses of pearl oyster.

► The full length PoCAT cDNA sequence has been reported. ► The phylogenetic tree was constructed based on catalases in this study. ► The PoCAT mRNA was expressed in all tested tissues, with highest level in intestine. ►The expression level of PoCAT mRNA in intestine after Vibrio alginolyticus stimulation has been reported. ► PoCAT might play an important role in innate immune responses of pearl oyster Pinctada fucata.

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Physical Sciences and Engineering Earth and Planetary Sciences Earth and Planetary Sciences (General)
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