Cloning and expression of the soybean DapA gene encoding dihydrodipicolinate synthase.
The rate-limiting step in the pathway for lysine synthesis in plants is catalyzed by the enzyme dihydrodipicolinate synthase (DS). We have cloned the portion of the soybean (Glycine max cv. Century) DapA cDNA that encodes the mature DS protein. Expression of the cloned soybean cDNA, as a lacZ fusion protein was selected in a dapA- Escherichia coli auxotroph. The DS activity of the fusion protein was characterized in E. coli extracts. The DS activity of the fusion protein was inhibited by lysine concentrations that also inhibited native soybean DS, while E. coli DS activity was much less sensitive to inhibition by lysine.
Silk
G W
GW
United States Department of Agriculture, Plant Molecular Biology Laboratory, Beltsville, MD 20705.
Matthews
B F
BF
Somers
D A
DA
Gengenbach
B G
BG
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D018548:Cotyledon / Q000378:metabolism; D017343:Genes, Plant / Q000235:genetics*; D006836:Hydro-Lyases / Q000096:biosynthesis / Q000187:drug effects / Q000235:genetics*; D008027:Light; D008239:Lysine / Q000096:biosynthesis / Q000494:pharmacology; D008969:Molecular Sequence Data; D010848:Picolinic Acids / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013025:Glycine max / Q000201:enzymology / Q000235:genetics* / Q000528:radiation effects
D010848:Picolinic Acids; D011993:Recombinant Fusion Proteins; C091033:dihydropicolinic acid; D006836:Hydro-Lyases; C020040:4-hydroxy-tetrahydrodipicolinate synthase; D008239:Lysine