title: Nucleic acids digestion by enzymes in the stomach of snakehead (Channa argus) and banded grouper (Epinephelus awoara).
abstract: Dietary nucleic acids (NAs) were important nutrients. However, the digestion of NAs in stomach has not been studied. In this study, the digestion of NAs by enzymes from fish stomach was investigated. The snakehead pepsins (SP) which were the main enzymes in stomach were extracted and purified. The purity of SP was evaluated by SDS-PAGE and HPLC. The snakehead pepsin 2 (SP2) which was the main component in the extracts was used for investigating the protein and NAs digestion activity. SP2 could digest NAs, including λ DNA and salmon sperm DNA. Interestingly, the digestion could be inhibited by treatment of alkaline solution at pH 8.0 and pepstatin A, and the digestion could happen either in the presence or absence of hemoglobin (Hb) and BSA as the protein substrates. Similarly, the stomach enzymes of banded grouper also showed the NAs digestion activity. NAs could be digested by the stomach enzymes of snakehead and banded grouper. It may be helpful for understanding both animal nutrition and NAs metabolic pathway.
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, China.|Innovation and Application Institute, Zhejiang Ocean University, Zhoushan, 316022, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, China.
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Innovation and Application Institute, Zhejiang Ocean University, Zhoushan, 316022, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Pan
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.affiliation: College of Biological Engineering, Jimei University, Xiamen, China.|Key Laboratory of Science and Technology for Aquaculture and Food Safety, Jimei University, Xiamen, China.
authors.forename: Minjie
authors.initials: M
authors.lastname: Cao
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, China. dongping@ouc.edu.cn.
authors.forename: Ping
authors.initials: P
authors.lastname: Dong
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, China. liangxg@ouc.edu.cn.
authors.forename: Xingguo
authors.initials: X
authors.lastname: Liang
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle; D004247:DNA / Q000378:metabolism*; D004063:Digestion / Q000187:drug effects; D029941:Fish Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006454:Hemoglobins / Q000494:pharmacology; D010434:Pepsin A / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D010436:Pepstatins / Q000494:pharmacology; D010473:Perciformes / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013270:Stomach / Q000201:enzymology*
chemical_list: D029941:Fish Proteins; D006454:Hemoglobins; D010436:Pepstatins; D012710:Serum Albumin, Bovine; D004247:DNA; D010434:Pepsin A; C031375:pepstatin
keywords: External nucleic acids; Feed; Fish; Pepsin; Stomach