Overexpression of an acidic endo-β-1,3-1,4-glucanase in transgenic maize seed for direct utilization in animal feed

PLoS One. 2013 Dec 31;8(12):e81993. doi: 10.1371/journal.pone.0081993. eCollection 2013.

Abstract

Background: Incorporation of exogenous glucanase into animal feed is common practice to remove glucan, one of the anti-nutritional factors, for efficient nutrition absorption. The acidic endo-β-1,3-1,4-glucanase (Bgl7A) from Bispora sp. MEY-1 has excellent properties and represents a potential enzyme supplement to animal feed.

Methodology/principal findings: Here we successfully developed a transgenic maize producing a high level of Bgl7AM (codon modified Bgl7A) by constructing a recombinant vector driven by the embryo-specific promoter ZM-leg1A. Southern and Western blot analysis indicated the stable integration and specific expression of the transgene in maize seeds over four generations. The β-glucanase activity of the transgenic maize seeds reached up to 779,800 U/kg, about 236-fold higher than that of non-transgenic maize. The β-glucanase derived from the transgenic maize seeds had an optimal pH of 4.0 and was stable at pH 1.0-8.0, which is in agreement with the normal environment of digestive tract.

Conclusion/significance: Our study offers a transgenic maize line that could be directly used in animal feed without any glucanase production, purification and supplementation, consequently simplifying the feed enzyme processing procedure.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animal Feed*
  • Animals
  • Ascomycota / enzymology
  • Ascomycota / genetics
  • Endo-1,3(4)-beta-Glucanase / genetics*
  • Endo-1,3(4)-beta-Glucanase / metabolism
  • Enzyme Stability
  • Food Additives
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Genes, Fungal
  • Genetic Vectors
  • Hydrogen-Ion Concentration
  • Plants, Genetically Modified
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Seeds / enzymology
  • Seeds / genetics
  • Zea mays / enzymology*
  • Zea mays / genetics*

Substances

  • Food Additives
  • Fungal Proteins
  • Recombinant Proteins
  • Endo-1,3(4)-beta-Glucanase

Grants and funding

This research was supported by the Key Program of Transgenic Plant Breeding 2013ZX08003-002, 2009ZX08003-020B (http://www.nmp.gov.cn/zxjs/zjy/201012/t20101208_2129.htm) and the China Modern Agriculture Research System CARS-42 (http://english.agri.gov.cn/hottopics/five/201304/t20130421_19483.htm). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.