Database Product Description
- Host Organism
- Glycine max (Soybean)
- Tolerance to glyphosate and ALS-inhibiting herbicides
- Trait Introduction
- Microparticle bombardment of plant cells or tissue
- Proposed Use
Production for human consumption and livestock feed.
- Product Developer
- DuPont Pioneer
Summary of Regulatory Approvals
Summary of Introduced Genetic Elements Expand
Characteristics of Glycine max (Soybean) Expand
Modification Method Expand
Characteristics of the Modification Expand
Environmental Safety Considerations Expand
Food and/or Feed Safety Considerations Expand
Soybean (Glycine max L. Merr.), is grown primarily for its seed which has many uses in the food and industrial sectors and represents one of the major sources of edible vegetable oil and of proteins for livestock feed use. A major food use of soybean in North America and Europe is as purified oil, used in margarines, shortenings, and cooking and salad oils. It is also a major ingredient in food products such as tofu, tempeh, soya sauce, simulated milk and meat products, and is a minor ingredient in many processed foods. Soybean meal is used as a supplement in feed rations for livestock. The major producers of soybeans are the United States, Brazil, Argentina, China, India, Paraguay and Canada.
Weeds are a major production problem in soybean cultivation. Typically, weeds are managed using a combination of cultural (e.g. seed bed preparation, using clean seed, variety selection, and planting date) and chemical controls. Depending on the production area and the prevalent weed species, herbicides may be applied before planting (e.g. pendimethalin, trifluralin, metribuzin), after planting but before emergence (e.g. pendimethalin, linuron, imazethapyr), and/or after emergence (e.g. bentazon, acifluorfen, fomesafen). Commonly, several different herbicides are required to adequately control weeds in soybean fields.
DP356043 has been transformed to express two novel genes, providing tolerance to two different classes of herbicide. The line contains two genes; gat4601 which provides tolerance to glyphosate by detoxifying the compound, while gm-hra encodes for a modified acetolactate synthase (ALS) enzyme which is not affected by the imidazolinone class of ALS inhibiting herbicides. The gat4601 gene is based on the sequences of three gat genes from the common soil bacterium Bacillus licheniformis. B. licheniformis is widespread in the environment; therefore, animals and humans are regularly exposed without adverse consequences to this organism and its components, such as the glyphosate N-acetyltransferase (GAT) protein. The GAT4601 protein is 84% homologous to each of the three native GAT proteins from which it was derived. In DP356043, the expression of the gat4601 gene is driven by the constitutive synthetic core promoter SCP1.
The GM-HRA protein in DP356043 is a modified version of the soybean GM-ALS protein. GM-ALS is involved in branched chain amino acid (leucine, isoleucine and valine) biosynthesis in the plastid. The herbicide tolerant gm-hra gene was made by isolating the herbicide sensitive soybean gm-als gene and introducing two specific amino acid changes, known to confer herbicide tolerance to tobacco ALS. The GM-HRA protein is >99% homologous to the native GM-ALS protein from which it was derived. In DP356043, the expression of the gm-hra gene is driven by the soybean constitutive S-adenosyl-L-methionine synthetase (SAMS) promoter.
There was no evidence of acute toxicity in mice for either GAT4601 or GM-HRA at doses of 1680 or 582 mg protein per kg of body weight, respectively. Based on the GAT4601 and GM-HRA protein levels in DP356043, exposure levels would be well below the tested doses. These data support the food and feed safety of the GAT4601 and GM-HRA proteins. The allergenic potential of the GAT4601 and GM-HRA proteins was assessed using a step-wise, weight-of-the evidence approach. Bioinformatic analyses revealed no identities to known or putative protein allergens or toxins for either the GAT4601 or GM-HRA amino acid sequences. Both the GAT4601 and GM-HRA proteins were non-glycosylated and heat labile. Both proteins hydrolyzed rapidly (within 30 seconds) in simulated gastric fluid. In simulated intestinal fluid the GAT4601 protein hydrolyzed within 2 minutes and the GMHRA protein hydrolyzed within 30 seconds.
Links to Further Information Expand
This record was last modified on Monday, November 2, 2015