Catalytic plasticity of fatty acid modification enzymes underlying chemical diversity of plant lipids

Science

Volumn 282, Issue 5392, 1998, Pages 1315-1317

  Broun, Pierre ^a   Shanklin, John ^b   Whittle, Ed ^b   Somerville, Chris ^a  

^a GEOPHYSICAL LABORATORY   (United States)

^b BROOKHAVEN NATIONAL LABORATORY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ARTICLE; CATALYSIS; CHEMICAL ANALYSIS; ENZYME ACTIVITY; ENZYME STRUCTURE; LIPID ANALYSIS; LIPOGENESIS; NONHUMAN; PLANT; PLANT SEED; PRIORITY JOURNAL;

EID: 0032515039     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.282.5392.1315     Document Type: Article

References (25)

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13. The seven mutations were V63A, G105A, N149T, F218Y, V296A, A323S, and I325M numbered relative to the LFAH12 sequence, where the first residue at the indicated position was mutated to the second residue. Single-letter abbreviations for the amino acid residues are as follows: A, Ala; C, Cys; D, Asp; E, Glu; F, Phe; G, Gly; H, His; I, Ile; K, Lys; L, Leu; M, Met; N, Asn; P, Pro; Q, Gln; R, Arg; S, Ser; T, Thr; V, Val; W, Trp; and Y, Tyr.
14. 7FAD2 cDNA encoding a modified FAD2 enzyme containing seven amino acid substitutions was achieved with overlap extension PCR. After the second round of assembly-amplification with the primers D5′ and D3′, the PCR products were treated exactly as the amplified wild-type FAD2 sequence described above. Plant expression constructs were introduced into Agrobacterium tumefaciens strain GV3101 pMP90 by electroporation and used to transform Arabidopsis fad2 mutant plants by vacuum infiltration [D. Bouchez, C. Camilleri, M. Caboche, C. R. Acad. Sci. Ser. Iii 316, 1188 (1993) ].
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25. We thank S. Stymne for communicating results before publication, and B. Behrouzian for helpful discussion. This work was supported in part by grants from the U.S. Department of Energy Office of Basic Energy Sciences to C.R.S. (DE-FG02-97ER20133), and to J.S. and E.J.W. The Monsanto Company awarded P.B. a fellowship.