Table III.

Identification of PM AP-associated proteins purified by NPA affinity chromatography

Purified ProteinPost-translational ModificationsInternal Fragment SequencedGenBank Protein Identification No.Amino Acids (Predicted)Characterized OrthologSimilarity
%
Aminopeptidases
 FII-103 (AtAPM1)GP (E,P)(K)TLEVPTDLVALSN CAB36783 879PS aminopeptidase M (mouse)/IRAP53
 FII-70 (AtAPP1)GP (E,P)(K)VSDEANSYFNGLG CAB16823 634Aminopeptidase P1 (human)60
 FIII-42 (AtAPM1Δ)GP (E,P)(R)VATVVAHELAHQWF CAB36783 UnknownTruncated form of AtAPM1∼68
AP-associated proteins
 FIII-68 (AtMyA1)GP (P)(R)SVFASAALGK AAB63637 619Myrosinase-associated protein (Brassica napus)62
 FII-55 (AtHSP70p)GP (E,P)(K)DVLK-(R)LVEHFAADEFNK CAB10440 484HSP70 (Arabidopsis)∼68
 FII-44/66 (AtFAGP2)GPI; GP (E,P)(K)AFSDILKSTGADK CAB40990 403Fasciclin-like arabinogalactan protein 2 (Arabidopsis)59
 FIII-40 (ATAPL1)GP (E,P)(K)LFVFGDSYADTGNI CAB82926 359Anther-specific Pro-rich protein (Arabidopsis)46
 FIII-24 (AtGSTF2)GP (P)(K)NISQYAIMAIQ P46422 212Auxin-binding GST II (Arabidopsis)100

Amino acid sequences of tryptic fragments from PM proteins contained in NPA affinity peaks II and III were obtained as described (see “Materials and Methods”). Protein identifications were assigned by NPA affinity fraction (FII or FIII) and SDS-PAGE apparent molecular mass. GenBank protein identification nos. were assigned if there was a unique database match with a similar predicted molecular mass. GP, Glycoprotein; GPI, glycosyl-phosphatidylinositol anchor; E, experimental evidence; P, predicted. K or R, Inferred lysine or arginine residues.