Читать книгу Molecular Mechanisms of Photosynthesis - Robert E. Blankenship - Страница 58

The lifeblood of a photosynthetic organism is its pigments. Without them, light cannot be absorbed, and therefore energy cannot be stored. There are a remarkable number of pigments found in different photosynthetic organisms, and they serve a variety of functional roles. In this chapter, we will learn about the different types of pigments, with an emphasis on how the chemical and spectroscopic properties of the pigments are determined by their structures and the functions that they perform in the photosynthetic process. The chlorophylls are named a–f, and the bacteriochlorophylls a–g, in order of their discovery. In addition, we will consider carotenoids and bilins, the two other major classes of photosynthetic pigments.

Chlorophylls have long been investigated (Scheer, 1991; Grimm et al., 2006). The word chlorophyll was first used by Pelletier and Caventou in 1818 to describe the green pigments that are involved in photosynthesis in higher plants. Three Nobel prizes have been given at least in part for studies on the structural determination of chlorophyll. Richard Wilstätter was honored in 1915 for his work that established the major features of the chlorophyll structure, including the empirical formula and the presence of magnesium (Mg). Hans Fischer was awarded the 1930 Nobel prize in part because he determined the complete structure, and Robert Woodward received the 1965 prize in part for his work that culminated in the total synthesis of chlorophyll.