Figure 2
Changes in cell growth and alkenone composition during 13C-labelling experiments performed at different temperatures. (A) Cell growth profiles at 25 °C (black bar on top) and 15 °C (open bar on top). Emiliania huxleyi cells were first incubated with 13C-bicarbonate at 25 °C for 3 days. Then, half of the culture was transferred to 15 °C, and the other half was maintained at 25 °C. (B) Changes in the contents of whole alkenones and alkenoates at 25 °C (black bar on top) and 15 °C (open bar on top). (C) Changes in the contents of various components of alkenones and alkenoates (FAME) at 25 °C (black columns) and 15 °C (open columns) from days 0 to 7. *K37:2 and K38:3Et could have contained small amounts of C36:2FAME and C36:2FAEE, respectively, because of difficulties in separating these out by GC-FID. The bold numbers with compounds represent alkenone and alkenoate species shown in Fig. 2F. (D) GC-FID chromatogram patterns of alkenone and alkenoate compounds in cells grown at 25 °C (upper) and 15 °C (lower) and harvested on day 7. The number attached to each compound/peak is the same as in Fig. 2F. (E) Changes in the GC-FID chromatogram profiles of alkenones and alkenoates in cells grown at 25 °C and then transferred to 15 °C. (F) Chemical structural formulas of alkenones. Numbers in parenthesis are the same as in Fig. 2C,D. Each value represents the average of triplicate experiments. Error bars represent means ± SD.
