Theme-Logo
  • Login
  • Home
  • Course
  • Publication
  • Theses
  • Reports
  • Published books
  • Workshops / Conferences
  • Supervised PhD
  • Supervised MSc
  • Supervised projects
  • Education
  • Language skills
  • Positions
  • Memberships and awards
  • Committees
  • Experience
  • Scientific activites
  • In links
  • Outgoinglinks
  • News
  • Gallery
publication name Cloning, expression, and characterization of a porcine pancreatic α-amylase in Pichia pastoris
Authors Lv-Hui Sun, Tao Qin, Yan Liu, Hua Zhao, Xin-Jie Xia, Xin Gen Lei
year 2018
keywords
journal Animal Nutrition
volume Not Available
issue Not Available
pages Not Available
publisher Not Available
Local/International International
Paper Link https://www.sciencedirect.com/science/article/pii/S2405654517301907
Full paper download
Supplementary materials Not Available
Abstract

Pancreatic α-amylase (α-1, 4-glucan-4-glucanohydrolase, EC.3.2.1.1) plays a primary role in the intestinal digestion of feed starch and is often deficient in weanling pigs. The objective of this study was to clone, express, and characterize porcine pancreatic α-amylase (PPA). The full-length cDNA encoding the PPA was isolated from pig pancreas by RT-PCR and cloned into the pPICZαA vector. After the resultant pPICZαΑ-PPA plasmid was transferred into Pichia pastoris, Ni Sepharose affinity column was used to purify the over-expressed extracellular recombinant PPA protein (rePPA) that contains a His-tag to the C terminus and was characterized against the natural enzyme (α-amylase from porcine pancreas). The rePPA exhibited a molecular mass of approximately 58 kDa and showed optimal temperature (50 °C), optimal pH (7.5), Km (47.8 mg/mL), and Vmax (2,783 U/mg) similar to those of the natural enzyme. The recombinant enzyme was stable at 40 °C but lost 60% to 90% (P < 0.05) after exposure to heating at ≥50 °C for 30 min. The enzyme activity was little affected by Cu2+ or Fe3+, but might be inhibited (40% to 50%) by Zn2+ at concentrations in pig digesta. However, Ca2+ exhibited a dose-dependent stimulation of the enzyme activity. In conclusion, the present study successfully cloned the porcine pancreatic α-amylase gene and over-expressed the gene in P.pastoris as an extracellular, functional enzyme. The biochemical characterization of the over-produced enzyme depicts its potential and future improvement as an animal feed additive.

Benha University © 2023 Designed and developed by portal team - Benha University