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The invention relates to a DNA fragment containing a determined gene, the expression of which inhibits the antibiotic and herbicidal effects of Bialaphos and related products. It also relates to recombinant vectors, containing such DNA fragment, which enable this protective gene to be introduced and expressed into cells and plant cells. The claims of this patent are directed to vectors carrying a gene encoding an enzymatic activity capable of inactivating a glutamine synthetase inhibitor by acetylation. Such genes would comprise a bar gene (as specified in Claim 2) as well as an acetyl transferase capable of inactivating an unspecified inhibitor, not necessarily phosphinothricin. [add a comment] Independent Claim 1 recites a vector which contains not only a gene that inactivates a glutamine synthetase inhibitor but also includes a plant promoter. Claim 25 extends the protection of the patent to any vector that contains the coding DNA fragment, regardless of the promoter that is used. [add a comment] A bar gene from Streptomyces viridochromogenes Printable Version http://www.patentlens.net/daisy/Phosph/ext/navaggregator/navaggregator 11 of 25 11/04/2007 4:14 PM The patent family discussed here is assigned to Hoechst AG. The patents in this family have restricted scope: the main independent claims are limited to a bar gene isolated from one specific strain of Streptomyces viridochromogenes (Actinobacteria: Actinomycetales), best exemplified by European patent EP 257 542 B1, and the same gene, codon-optimized for expression in plant cells, as in patent EP 275 975 B1. These patents, which fall within the literal scope of the claims of the assigned patent family discussed previously, are also now part of the consolidated patent portfolio of Bayer Crop Science. [add a comment] The Hoechst family consists of related patents and applications in many jurisdictions, including several in Europe, as well as in Australia, Canada, China, Israel, Japan, New Zealand, South Africa and the U.S. Unusually, no PCT application was filed for conversion into the numerous jurisdictions. [add a comment] A summary of the claims in this patent family can be seen below. [add a comment] Assigned to Hoechst AG EP 257 542 B1 2 Mar 1988 A bar gene obtained from a Streptomyces viridochromogenes strain* and plant cells transformed with that gene. Also a process to acetylate PPT using bacteria expressing the gene and the enzyme as such. View Claims EP 275 957 B1 27 Aug 1988 A plant codon-optimized bar gene isolated from the same bacterial strain as above*. The modifications consist of an altered G/C ratio and elimination of potentially deleterious palindromic sequences. View Claims US 5,273,894 28 Dec 1993 A bar gene obtained from same bacterial strain as above* and plant cells transformed with that gene. Also a process to acetylate PPT using bacteria expressing the gene and the enzyme as such. View Claims US 5,637,489 10 Jun 1997 A process to produce plant cells resistant to PPT by introducing the same bar gene described above and the resulting resistant plants. View Claims US 5,879,903 9 Mar 1999 A method to select bacterial or plant cells using the bar gene described above as a selectable marker. View Claims US 5,276,268 4 Jan 1994 A plant codon-optimized bar gene isolated from same bacterium as above*. Modifications consist of an altered G/C ratio and elimination of potentially deleterious palindromic sequences. View Claims Related patents: EP in force in Germany DE 3778792 C0, Austria AT 75776, Belgium, Switzerland, France, Great Britain, Greece GR 3005200, Spain ES 2038631 T3, Italy, Sweden; other related patents: Australia AU 604743, Canada CA 1337597, CA 1321364, Finland FI 100251 B1, Hungary HU 217208 B, HU 215079 B, Japan JP 2993964 B2, JP 2749424 B2, JP 2815847 B2, JP 3093686 B2, JP 7097994 B4. Related applications: China CN 1040772 B, CN 1225393, Denmark DK 4378/87, Finland FI 88/0216, Greece GR 3007859 T3, Israel IL 83604 A0, IL 85143 A0, Japan JP 7097994 B4, JP 3103193 A2, JP 63071183 A2, JP 63273479 A2, JP 7147985 A2, JP 9107981 A2, JP 10080278 A2, JP 10080289 A2, New Zealand NZ 221526 A, South Africa ZA 87/06210 A, ZA 88/00368 A *Streptomyces viridochromogenes strain DSM 40736 (catalog #DSM 4112, deposit under the Budapest Convention) obtained from the German Collection of Microorganisms and Cell Cultures (DSMZ). [add a comment] EP 257 542 The European patent EP 257 542 protects the use of a specific strain of Streptomyces viridochromogenes. [add a comment] Widely protected in many jurisdictions, the independent claim of this patent recites a bar gene from a specific Streptomyces viridochromogenes strain, DSM 4112. Dependent claims recite the use of the bar gene from strain DSM 4112 as a selectable marker for genetically modified bacterial and plant cells. The use of the bar gene as a selectable marker in bacteria (not mentioned in the claims of the "Dominant bar gene patents" belonging to Plant Genetic Systems (PGS)) is restricted here to the bar gene as described in Claim 1. [add a comment] Any phosphinothricin-resistant plants that contain the described bar gene are also protected (Claim 8). [add a comment] Claim 7 recites another use of the bar gene isolated from S. viridochromogenes not present in the claims of Printable Version http://www.patentlens.net/daisy/Phosph/ext/navaggregator/navaggregator 12 of 25 11/04/2007 4:14 PM the dominant patents, namely to acetylate L-phosphinothricin. This acetylated compound is of commercial interest in another field of application, the selective destruction of tissues expressing the deacetylase gene, e.g. for the production of male sterile plants when the gene is expressed in the pollen sac. [add a comment]