DEDUCED AMINO-ACID-SEQUENCE OF 2S STORAGE PROTEIN FROM BRASSICA SPECIES AND THEIR CONSERVED STRUCTURAL FEATURES

2S seed storage albumin coding regions from five Brassica species, nam ely Brassica campestris, B. oleracea, B. nigra, B. juncea, and B. cari nata have been cloned by PCR amplification of genomic DNA using oligon ucleotide primers and their nucleotide sequences have been determined. These sequences showed more than 85% homology amongst themselves and considerable homology with some other crucifer 2S protein coding seque nces. The deduced amino acid sequences showed more homology due to som e inconsequential mutations in codons without changing the amino acids . Computer analysis of the protein sequences for possible secondary st ructure revealed a high degree of conservation of hydrophilic and hydr ophobic domains and the invariant positions of cysteine residues. Unro oted phylogenic tree based on the coding region of 2S albumin from dif ferent Brassica species cloned by us and published sequences from othe r Cruciferae indicated that these genes originated before the evolutio nary divergence of different Brassica species and were conserved due t o some stringent structural and functional features required for seed metabolism.