The architecture of starch blocklets follows phyllotaxic rules

25 November 2020
We have just published in Nature-Scientic Reports, the results of our collaboration with the Polytechnic University of Marche (Italy) and the ESRF - European Synchrotron Radiation Facility in Grenoble (France), which is related to the application of the rules of starch grain phyllotaxis that leads to a new model of its architecture and the structure of amylopectin. Click on the title for more information.

Abstract:
“The starch granule is Nature’s way to store energy in green plants over long periods. Irrespective of their origins, starches display distinct structural features that are the fingerprints of levels of organization over six orders of magnitude. We hypothesized that Nature retains hierarchical material structures at all levels and that some general rules control the morphogenesis of these structures. We considered the occurrence of a «phyllotaxis» like features that would develop at scales ranging from nano to micrometres, and developed a novel geometric model capable of building complex structures from simple components. We applied it, according to the Fibonacci Golden Angle, to form several Golden Spirals, and derived theoretical models to simulate scattering patterns. A GSE, constructed with elements made up of parallel stranded double-helices, displayed shapes, sizes and high compactness reminiscent of the most intriguing structural element: the ‘blocklet’. From the convergence between the experimental findings and the theoretical construction, we suggest that the «phyllotactic» model represents an amylopectin macromolecule, with a high molecular weight. Our results offer a new vision to some previous models of starch. They complete a consistent description of the levels of organization over four orders of magnitude of the starch granule.”

The article is availaible over here: https://www.nature.com/articles/s41598-020-72218-w