کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1188935 | 963502 | 2009 | 11 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Subunit structure of the vicilin-like globular storage protein of cocoa seeds and the origin of cocoa- and chocolate-specific aroma precursors Subunit structure of the vicilin-like globular storage protein of cocoa seeds and the origin of cocoa- and chocolate-specific aroma precursors](/preview/png/1188935.png)
Essential cocoa-specific aroma precursors are generated during fermentation of cocoa seeds by proteolysis of the vicilin-like globulin. This particular storage protein consists of three subunits with apparent molecular masses of 47 kDa, 31 kDa, and 15 kDa, respectively, which are derived from a common 66-kDa precursor. Since all these subunits resist N-terminal sequencing by Edman degradation, we have analysed the localisation of these vicilin subunits on their common precursor sequence by MALDI-TOF-MS analyses of their tryptic fragments. The results were corroborated by epitope mapping of polyclonal antibodies using 185 overlapping pentadeca-peptides covering the whole sequence of the precursor. The results show that the cocoa vicilin is encoded by a single gene and that heterogeneity of the vicilin subunits must be attributed to statistical post-translational modifications. Localisation of the precursor regions, from which the various subunits are derived, will be helpful for the future identification of aroma-relevant peptides generated during the fermentation process.
Journal: Food Chemistry - Volume 113, Issue 4, 15 April 2009, Pages 903–913