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We report the generation of transgenic soybean [Glycine max (L.) Merr.] via Agrobacterium-mediated gene transfers of a cry1A gene (tic107) from Bacillus thuringiensis (Bt) that exhibits a high degree of resistance against the lepidopteran pests Pseudoplusia includens (Walker) (soybean looper), Helicoverpa zea (Boddie) (soybean podworm), and Anticarsia gemmatalis Hubner (velvetbean caterpillar). Three transgenic soybean lines (862, 726, and 781) were evaluated for expression, molecular composition, efficacy against target pests, and agronomic characteristics. We have designed and tested an expression cassette that consistently and reproducibly generates transgenic soybeans that accumulate the tic107 protein at levels as high as 6.12 [micro]g [mg.sup.-1] of total extractable protein. Expression levels of this magnitude of a Bt insecticidal protein have never been reported in soybean. Previous reports have indicated expression levels 100-fold lower in the highest-expressing lines. In addition, the phenotypes of these high-expressing lines were indistinguishable from their negative segregant and the transformation parent (Asgrow var. 'A3237'). Insect bioassay data demonstrate complete protection against soybean looper, soybean podworm, and velvetbean caterpillar when negative controls exhibited defoliation as high as 98%. Unlike previous reports of transgenic soybeans, we report here highly efficacious, single-copy, and normal phenotypes of transgenic soybean plants containing the highly expressed cry1A gene.

Genes encoding two distinct D-amino acid biosynthetic enzymes from Bacillus sphaericus ATCC 10208 were cloned and characterized using a complementation screen with Escherichia coli WM335. Assays indicated that the isolated genes encoded a purified D-amino acid transaminase and a previously undetected glutamate racemase. The presence of the two enzymes in the B. subtillis suggested that the bacilli possesses two biosynthetic routes to D-glutamate.

Reports on the study of the expression of pykF-lacZ as a function of the carbon source in wild-type strains and strains lacking or overproducing the FruR protein of Escherichia coli. Methodology; Results; References.