Rapid determination of parvalbumin amino acid sequence from Rana catesbeiana (pI 4.78) by combination of ESI mass spectrometry, protein sequencing, and amino acid analysis
H. Taka et al., Rapid determination of parvalbumin amino acid sequence from Rana catesbeiana (pI 4.78) by combination of ESI mass spectrometry, protein sequencing, and amino acid analysis, J BIOCHEM, 127(5), 2000, pp. 723-729
The complete amino acid sequence of beta-type parvalbumin (PA) from bullfro
g Rana catesbeiana (pI 4.78) was determined by tandem mass spectrometry in
combination with amino acid analysis and peptide sequencing following Arg-C
and V-8 protease digestion The primary structure of the protein was compar
ed with that of beta-type PA from R. esculenta (pI 4.50), with which it is
highly homologous. Compared with R. esculenta beta-type PA4.50, R. catesbei
ana P-type parvalbumin (PA4.78) differed in 15 out of 108 amino acid residu
es (14% displacement), PA4.78 had Cys at residue 64 and was acetylated at t
he amino terminus, but 25 residues of the carboxyl terminus were completely
conserved. Several amino acid displacements were found between residues 51
and 80 (30% displacement), although the functionally important sequence of
PA was completely conserved. The amino acids residues of putative calcium-
binding sites were Asp-51, Asp-53, Ser-55, Phe-57, Glu-59, Glu-62, Asp-90,
Asp-92, Asp-94, Lys-96, and Glu-101, which were conserved in all alpha and
beta-types of R. catesbeiana as well as other parvalbumins. In addition, Ar
g-75 and Glu-81, which are thought to form a salt bridge located in the int
erior of the molecule [Coffee, C.J. et al. (1976) Biochim. Biophys. Acta 45
3, 67-80], were also conserved in PA4.78.