Comparative biochemical characteristics of HPAPs

PeptideHPLC peak no.aMolecular mass (Da)bN-terminal or partial sequencecC-terminal sequencedNet charge at pH:eConcn in platelets (nmol/1010 platelets)f
FP-B21,551.6 (1,551.6)G2VNDNEEGFFSA13ND−3.00−2.88<1.0
Tβ-434,962.2 (4,963.5)K18KTETQEKNPLPSKE32G-E-S (0.1-0.1-0.8)−3.00−2.522.0
PBP410,260.6 (10,261.9)S1STKGQTKRNLAKGK15ND+3.55+5.952.0
CTAP-359,287.0 (9,287.8)N1LAKGKEESLDSDLY15S-A-D (0.1-0.3-0.4)+0.53+2.9523
RANTES67,850.5 (7,847.1)S1PYSSDTTPCCFAYI15ND+4.52+5.990.2
PF-477,765.0 (7,766.2)E1AEEDGDLQCLCVKT15L-L-E-S (2.2-0.8-2.8)+2.57+4.8415
  • a See Fig. 2.

  • b Molecular masses determined by mass spectrometry compared with those (in parentheses) calculated from amino acid sequences of corresponding peptides (see references in the text).

  • c Sequences of the peptides are shown in single-letter code. The numbering of residues is matched to the sequences of the corresponding peptides.

  • d Released amounts (nanomoles) of C-terminal amino acids upon digestion with carboxypeptidase Y are shown in parentheses. The C-terminal sequences of peaks 3, 5, and 7 were identical with those of the respective peptides.

  • e Net charges were calculated by using the pI Graph Viewprogram in the GeneWorks (version 2.5.1) suite.

  • f Approximate content of each peptide in the released material of platelets based on quantity of recovery as described in Results.

  • g not determined.