Fractionation of Tomato Fruit Chromoplasts.

Chromoplast differentiation involves an active synthesis of carotenoids associated with the remodeling of the preexisting plastid membrane systems to form specialized structures involved in the sequestration and storage of the synthesized carotenoids. These subplastidial structures show remarkable morphological differences and seem to be adapted to the accumulation of particular carotenoids in some plant species and organs. At present, very little is known about chromoplast biogenesis and the role of the different suborganellar structures in the synthesis and storage of carotenoids.

A single-molecule force spectroscopy nanosensor for the identification of new antibiotics and antimalarials.

An important goal of nanotechnology is the application of individual molecule handling techniques to the discovery of potential new therapeutic agents. Of particular interest is the search for new inhibitors of metabolic routes exclusive of human pathogens, such as the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway essential for the viability of most human pathogenic bacteria and of the malaria parasite. Using atomic force microscopy single-molecule force spectroscopy (SMFS), we have probed at the single-molecule level the interaction of 1-deoxy-D-xylulose 5-phosphate synthase (DXS), which catalyzes the first step of the MEP pathway, with its two substrates, pyruvate and glyceraldehyde-3-phosphate.