Fig. 1.

Fms1-encoded amine oxidase is necessary for spermine-to-spermidine conversion in vivo.[¹⁴C]Spermine (113 mCi/mmol, 50 μCi/ml) was added at 10^–6 M concentration to the partially amine-depleted spe3Δ FMS1⁺ (Y551) and spe3Δ fms1Δ (Y549) cultures as mentioned in the text. Cells were harvested, and polyamines were extracted and run on a Polygram cation-exchange chromatographic plate with 2 M KCl. Results were obtained by scanning a Fuji BAS-MS imaging plate as mentioned in Materials and Methods. The scanned values are expressed in percent of [¹⁴C]spermine-to-[¹⁴C]spermidine conversion and are shown below each figure. The right-hand lane contains standard [¹⁴C]spermine. (The calculated values were corrected for a 0.3% contamination of radioactive spermidine in commercial [¹⁴C]spermine.) [R_f values: spermine (SPM), 0.17; spermidine (SPD), 0.33.]