Purification of Zea m 1 isoforms from maize pollen. A, Fractionation of the
maize pollen extract by CM-Sepharose cation exchange chromatography yielded
three peaks of activity (I–III). B, Fractionation of peaks I and II from
A on a silica-based CM-HPLC column yielded four peaks of activity, which were
identified as four isoforms of Zea m 1 by immunoblot analysis. C,
Fractionation of peak III from A yielded isoforms Zea m 1c and 1d. Open
circles, Wall extension activity of the corresponding fraction.