The concept of enhancement and the two light reactions arose from these experiments. In the same review, p. 209, Vernon and Avron also said that part of “the evidence for two pigment systems in photosynthesis was Blinks’s Ulva work (Haxo and Blinks 1950; Yocum and Blinks 1950, 1954; Blinks 1957, 1959) which caused a pulse of oxygen evolution, the height and duration of which depend on the history of the cell.” In a review on phycobilins

and phycobilisomes, Tandeau de Marsac (2003) stated: About 60 years later, however, the major role of the different phycobilins from red algae and cyanobacteria Vactosertib mouse in light-harvesting for photosynthesis was largely confirmed and quantitatively MDV3100 nmr established by several groups (Emerson and Lewis 1942; Blinks 1954a, b; Brody and Emerson 1959; Lemasson et al. 1973).

Tandeau de Marsac also mentioned: The discovery of two spectrally slightly different phycoerythrins in primitive red algae of the order of Bangiales (Bangiophyceae) B-phycoerythrin (Airth and Blinks 1956) and the b-phycoerythrin (Gantt and Lipschultz 1974); the nomenclature of “R” for red algae was no longer valid. Consequently, these prefixes no more refer to the type of source organisms but denote their specific spectral characteristics. In reevaluating Blinks’s contributions, Raven and Giraud-Bascoe (2001, p. 946) concluded: The second investigation of the Emerson [Enhancement] effect (Emerson et al. 1957;

Emerson and Chalmers 1958)… was ‘found’ in the work of Blinks (1957, 1960a, b) on chromatic transients, involving sequential rather than simultaneous supply of the irradiation of different wavelengths to marine macroalgae. Blinks was forced to use sequential rather than simultaneous irradiations because Idelalisib he had used only one monochromator. However, Blinks’s approach allowed him to confirm that enhancement did not necessarily involve simultaneous irradiation and so involved interaction between the different wavelengths at the level of chemical products of photochemistry rather than at the level of excitation energy or photochemistry. According to Govindjee (pers. commun.), Emerson et al. (1957) used a shaking vessel, and the two light beams he used were also absorbed by the cells with some time delay; thus, they were also not quite ‘simultaneous’. Further, the two light effect was clearly shown to be not in respiration, as Blinks had thought: (a) R. Govindjee et al. (1960) discovered a two-light effect in a benzoquinone Hill reaction in Chlorella cells, where benzoquinone had inhibited respiration; (b) Govindjee et al. (1963) showed, using mass spectroscopy, that the effect was in photosynthesis, not in respiration. Later, Govindjee and R.