UHPLC–MS/MS analysis of cocoa bean proteomes from four different genotypes

Abstract

In this study the proteomic profiles of cocoa beans from four genotypes with different flavour profiles were analysed by bottom-up label-free UHPLC-MS/MS. From a total of 430 identified proteins, 61 proteins were found significantly differentially expressed among the four cocoa genotypes analysed with a fold change of ≥2. PCA analysis allowed clear separation of the genotypes based on their proteomic profiles. Genotype-specific abundances were recorded for proteases involved in the degradation of storage proteins and release of flavour precursors. Different genotype-specific levels of other enzymes, which generate volatiles compounds that could potentially lead to flavour-inducing compounds, were also detected. Overall, this study shows that UHPLC-MS/MS data can differentiate cocoa bean varieties.

The pathogen Moniliophthora perniciosa promotes differential proteomic modulation of cacao genotypes with contrasting resistance to witches´ broom disease

“…It was highly represented in the RT library of the resistant interaction between T. cacao and M. perniciosa [13]. These inhibitor shows high abundance in proteomic profile of cacao seed [75], zygotic embryo during development [28] and cacao root submitted to flooding [76] , and in cacao leaves also varies in response to heavy metal stress [77]. The most abundant proteinases in the genome of M. perniciosa are deuterolysins, a type of fungal metalloproteinases that are similar to bacterial thermolysin [10].…”

The pathogen Moniliophthora perniciosa promotes differential proteomic modulation of cacao genotypes with contrasting resistance to witches´ broom disease.

“…It was highly represented in the RT library of the resistant interaction between T. cacao and M. perniciosa [13]. These inhibitor shows high abundance in proteomic profile of cacao seed [75], zygotic embryo during development [76] and cacao root submitted to flooding [77], and in cacao leaves also varies in response to heavy metal stress [78]. The most abundant proteinases in the genome of M. perniciosa are deuterolysins, a type of fungal metalloproteinases that are similar to bacterial thermolysin [10].…”

Proteomic and peptidomic UHPLC-ESI MS/MS analysis of cocoa beans fermented using the Styrofoam-box method

“…Defatting of the beans was performed following a previously published procedure (Scollo, Neville, Oruna-Concha, Trotin, & Cramer, 2019) Fat was extracted from ground snapfrozen cocoa beans with petroleum ether (three times) by centrifugation and discarding the supernatant. For protein analysis approximately 160 mg of ground cocoa bean powder was used, while 200 mg of bean material was defatted for peptide analysis.…”

“…Removal of polyphenols was carried out following the protocol published by Scollo et al (Scollo, Neville, Oruna-Concha, Trotin, & Cramer, 2019). Briefly, polyphenols were extracted from the defatted bean material three times using 3.5 ml of a wash solution (5 mM sodium ascorbate in 80% acetone / 20% water).…”