Dr. Webb's research interests center on biomineralization, biologically controlled mineral deposition, in plants. In the same way that animals fabricate biominerals in precise forms, such as bones, teeth, seashells, and spicules, plants also produce specific kinds of biominerals with distinct characteristics. Although biominerals in animals have clearly defined functions, relatively little has been known about their roles in plants. Most seed plants accumulate some type of biomineral, usually calcium oxalate, calcium carbonate, or silica, and divergent plant taxa exhibit species-specific patterns of mineral type, structure, and distribution. Dr. Webb's interests have focused on understanding how certain plants synthesize unique needle-shaped crystals of calcium oxalate, called raphides, that provide defense against herbivory. Raphides develop inside membrane compartments, surrounded by a carbohydrate-rich matrix, within vacuoles of highly specialized cells. To define the role of the vacuolar matrix in raphide initiation and growth, her research has focused on identifying and characterizing proteins or other macromolecules associated with raphide development. They also have potential applications in such diverse areas as medicine, materials engineering, and bioenergy.
Recently, Dr. Webb has investigated a role for calcium oxalate in photosynthesis . The grass, Setaria, viridis, accumulates calcium oxalate crystals in mesophyll cells of the leaves. During the daytime, crystals decrease in size and exhibit pitting on crystal surfaces. In contrast, during the night crystal size increases and surface pits are no longer present.
Dr. Webb teaches an undergraduate course in Plant Anatomy (BTNY 31600) for plant biology majors, and she also enjoys working with undergraduates on independent research projects.