Agency Response Letter GRAS Notice No. GRN 000175
CFSAN/Office of Food Additive Safety
January 6, 2006
Hendrik J.J. van Vuuren, Ph.D.
First Venture Technologies Corporation.
885 West Georgia Street
Vancouver, British Columbia, V6C 3E8
Re: GRAS Notice No. GRN 000175
Dear Dr. van Vuuren:
The Food and Drug Administration (FDA) is responding to the notice, dated July 5, 2005, that First Venture Technologies Corporation (First Venture) submitted in accordance with the agency's proposed regulation, proposed 21 CFR 170.36 (62 FR 18938; April 17, 1997; Substances Generally Recognized as Safe (GRAS)). FDA received this notice on July 7, 2005, filed it on July 12, 2005, and designated it as GRN No. 000175.
The subject of the notice is Saccharomyces cerevisiae strain ECMo01, which carries a recombinant genetic insert. The genetic insert is composed of three elements, DUR1,2 gene, a promoter and a terminator, all derived from different strains of S. cerevisiae. The promoter and the terminator are necessary for the proper expression of the DUR1,2 gene. The DUR1,2 gene encodes S. cerevisiae urea amidolyase enzyme (urea amidolyase). Strain ECMo01 was developed by inserting the recombinant genetic insert into the S. cerevisiae parental strain Davis 522, which is commonly used in the wine industry.
First Venture states that strain Davis 522 contains its own DUR1,2 gene, which is not normally active during alcoholic fermentation. Thus, the purpose of creating S. cerevisiae strain ECMo01 is to increase the expression of S. cerevisiae urea amidolyase. The urea amidolyase catalyzes the hydrolysis of urea that is produced by S. cerevisiae during alcoholic fermentation. Urea is a precursor of ethyl carbamate, a suspected carcinogen in humans, which is formed in the wine from the reaction of urea and ethanol. Hydrolysis of urea by urea amidolyase significantly reduces the potential for formation and accumulation of ethyl carbamate in the wine.
The notice informs FDA of the view of First Venture that strain ECMo01 is GRAS, through scientific procedures, for use as a starter culture in alcoholic beverage fermentation. First Venture has determined that strain ECMo01 is substantially equivalent to strain Davis 522 from which it was derived, except for the fully characterized introduced genetic insert and expressed levels of S. cerevisiae urea amidolyase.
First Venture describes published and unpublished information about the development of its strain ECMo01. In the notice, First Venture describes the details of the construction of the genetic insert, as well as its molecular characterization and stability assessment in strain ECMo01. First Venture states that the genetic insert does not contain any undesired sequences and it is genetically stable. First Venture states that strain Davis 522 is commonly used in industry to obtain wine active dry yeast and it has never been shown to produce allergenic or toxic substances.
First Venture states that they carried out risk assessments related to the presence of potential unintended gene products as a result of the genetic modification using computer-based sequence analyses. Their sequence analyses revealed a theoretical possibility of production of three additional proteins due to the integration of the genetic insert in strain ECMo01. First Venture asserts that further sequence analyses revealed that the production of these additional proteins is unlikely, and even in the extremely unlikely event of production of these proteins, there should be no concern because their amino acid sequences will be similar to those found in strain Davis 522, which has never been shown to produce unwanted products.
First Venture describes generally available information on wine making procedures and states that use of the strain ECMo01 does not lead to any changes in these procedures or in the composition of the wine. First Venture states that urea amidolyase is present in all wine yeast cells currently used by the wine industry. Therefore, the only significant difference expected between wines produced using strain Davis 522 and wines produced using strain ECMo01, is the possible presence of minor amounts of recombinant urea amidolyase. However, the clarification and stabilization processes, which are obligatory in commercial winemaking, will remove most of this enzyme and its larger fragments.
First Venture describes generally available information on the clarification and stabilization of wine and explains how the remaining urea amidolyase could be removed during these processes. During wine clarification, solid particles may be allowed to settle by gravity or centrifugation. First Venture states that this clarification process removes most of the yeast cells. When the wine is kept on the lees for ageing, the yeast cells undergo autolysis, releasing cellular materials that are degraded through the action of enzymes. Further, white wines can be treated with bentonite to remove all remaining protein fractions. In red wines, tannins associate with proteins. This protein-tannin complex can be precipitated by adding gelatin or egg white albumin. First Venture states that prior to bottling most wines undergo filtration (e.g., with diatomaceous earth, cellulose filters, or membrane filters) that also eliminates any remaining yeast cells. First Venture concludes that use of the strain ECMo01 will not result in any additional urea amidolyase in wines at the time they are consumed.
Based on the information provided by First Venture, as well as other information available to FDA, the agency has no questions at this time regarding First Venture's conclusion that Saccharomyces cerevisiae strain ECMo01 encoding S. cerevisiae urea amidolyase enzyme is GRAS under the intended conditions of use. The agency has not, however, made its own determination regarding the GRAS status of the subject use of Saccharomyces cerevisiae strain ECMo01. As always, it is the continuing responsibility of First Venture to ensure that food ingredients that the firm markets are safe, and are otherwise in compliance with all applicable legal and regulatory requirements.
In accordance with proposed 21 CFR 170.36(f), a copy of the text of this letter, as well as a copy of the information in your notice that conforms to the information in proposed 21 CFR 170.36(c)(1), is available for public review and copying on the homepage of the Office of Food Additive Safety (on the Internet at http://www.cfsan.fda.gov/~lrd/foodadd.html).
Laura M. Tarantino, Ph.D.
Office of Food Additive Safety
Center for Food Safety and Applied Nutrition