NPQ development <i>versus</i> diatoxanthin (DT) amount in WT and two <i>Dde</i> transformants of <i>Phaeodactylum tricornutum</i> cells grown under low light.

<p>(A): NPQ and DT data obtained as a function of light intensity for a 5 min light exposure (data from Fig. 2A and 2B, and Fig. 4B), (B): NPQ and DT were measured as a function of time at an irradiance of 450 µmol photons⋅m⁻²⋅s⁻¹ (data from Fig. 2C and 2D, and Fig. 4A). The linear NPQ/DT relationships in (A) obtained for WT was NPQ = 0.45 DT (R² = 0.98), for AS-198 NPQ = 0.24 DT (R² = 0.83) from about 1 mol DT/100 mol Chl <i>a</i>, and for IR-5 NPQ = 0.23 DT (R² = 0.97). Values are averages, ± SD of three to four measurements. See the text for details.