Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation

Safety and efficacy of l-threonine produced by fermentation using Escherichia coli CGMCC 7.232 for all animal species

EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) et al. EFSA J. .

Abstract

The product subject of this assessment is l-threonine produced by fermentation with a genetically modified strain of Escherichia coli (CGMCC 7.232). It is intended to be used in feed and water for drinking for all animal species and categories. The production strain and its recombinant DNA were not detected in the additive. The product l-threonine, manufactured by fermentation with E. coli CGMCC 7.232, does not raise any safety concern with regard to the genetic modification of the production strain. l-Threonine produced using E. coli CGMCC 7.232 is considered safe for the target species. The FEEDAP Panel has concerns regarding the safety of the simultaneous administration of l-threonine via water for drinking and feed. l-Threonine produced using E. coli CGMCC 7.232 is safe for the consumer. In absence of data, the FEEDAP Panel cannot conclude on the potential of the additive to be irritant to skin and eyes or to be a skin sensitiser. There is a risk from the inhalation exposure to endotoxins for persons handling the additive. l-Threonine produced using E. coli CGMCC 7.232 is safe for the environment. The product under assessment is considered an efficacious source of the amino acid l-threonine for all animal species. For l-threonine to be as efficacious in ruminants as in non-ruminant species, it requires protection against degradation in the rumen.

Keywords: amino acids and their salts and analogues; efficacy; genetically modified microorganisms; l‐threonine; nutritional additives; safety.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Molecular structure of l‐threonine
See this image and copyright information in PMC

References

    1. Bauer AP, Dieckmann SM, Ludwig W and Schleifer KH, 2007. Rapid identification of Escherichia coli safety and laboratory strain lineages based on Multiplex‐PCR. FEMS Microbiology Letters, 269, 36–40. - PubMed
    1. Cort N, Fredriksson G, Kindahl H, Edqvist LE and Rylander R, 1990. A clinical and endocrine study on the effect of orally administered bacterial endotoxin in adult pigs and goats. Journal of Veterinary Medicine, A‐Physiology Pathology, Clinical Medicine. 37, 130–137. - PubMed
    1. EFSA (European Food Safety Authority), 2008. Technical Guidance: Microbial Studies. The EFSA Journal, 836, 1–3.
    1. EFSA FEEDAP Panel (EFSA Panel on Additives and Products or Substances Used in Animal Feed), 2010. Scientific Opinion on the use of feed additives authorised/applied for use in feed when supplied via water. EFSA Journal 2010;8(12):1956, 9 pp. 10.2903/j.efsa.2010.1956 - DOI
    1. EFSA FEEDAP Panel (EFSA Panel on Additives and Products or Substances used in Animal Feed), 2012a. Guidance for the preparation of dossiers for nutritional additives. EFSA Journal 2012;10(1):2535, 14 pp. 10.2903/j.efsa.2012.2535 - DOI

LinkOut - more resources