title: Isoprenoid, lipid, and protein contents in intact plastids isolated from mesocarp cells of traditional and high-pigment tomato cultivars at different ripening stages.
abstract: This study reports quali-quantitative analyses on isoprenoids, phospholipids, neutral lipids, phytosterols, and proteins in purified plastids isolated from fresh fruits of traditional (Donald and Incas) and high-pigment (Kalvert and HLY-18) tomato cultivars at four ripening stages. In all of the investigated cultivars, lycopene, β-catotene, lutein, and total carotenoids varied significantly during ripening. Chromoplasts of red-ripe tomato fruits of high-pigment cultivars accumulated twice as much as lycopene (307.6 and 319.2 μg/mg of plastid proteins in Kalvert and HLY-18, respectively) than ordinary cultivars (178.6 and 151.7 μg/mg of plastid proteins in Donald and Incas, respectively); differences in chlorophyll and α-tocopherol contents were also evidenced. Phospholipids and phytosterols increased during ripening, whereas triglycerides showed a general decrease. Regardless of the stage of ripening, palmitic acid was the major fatty acid in all cultivars (ranging from 35 to 52% of the total fatty acids), followed by stearic, oleic, linoleic, linolenic, and myristic acids, but their relative percentage was affected by ripening. Most of the bands detected on the SDS-PAGEs of plastid proteins were constantly present during chloroplast-to-chromoplast conversion, some others disappeared, and only one, with a molecular weight of ~41.6 kDa, was found to increase in intensity.
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali (DiSTeBA), Università del Salento, Lecce, Italy.
authors.forename: Marcello S
authors.initials: MS
authors.lastname: Lenucci
authors.forename: Lucia
authors.initials: L
authors.lastname: Serrone
authors.forename: Monica
authors.initials: M
authors.lastname: De Caroli
authors.forename: Paul D
authors.initials: PD
authors.lastname: Fraser
authors.forename: Peter M
authors.initials: PM
authors.lastname: Bramley
authors.forename: Gabriella
authors.initials: G
authors.lastname: Piro
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Dalessandro
mesh_terms: D002338:Carotenoids / Q000032:analysis; D005638:Fruit / Q000737:chemistry / Q000254:growth & development* / Q000648:ultrastructure; D008055:Lipids / Q000032:analysis*; D018551:Solanum lycopersicum; D010840:Phytosterols / Q000032:analysis; D010860:Pigments, Biological / Q000032:analysis; D010940:Plant Proteins / Q000032:analysis*; D018087:Plastids / Q000737:chemistry*; D013045:Species Specificity; D013729:Terpenes / Q000032:analysis*
chemical_list: D008055:Lipids; D010840:Phytosterols; D010860:Pigments, Biological; D010940:Plant Proteins; D013729:Terpenes; D002338:Carotenoids