The amino acid sequence of bovine intestinal calcium-binding protein

The complete amino acid sequence of the vitamin D-dependent bovine intestinal calcium-binding protein (minor A component) has been determined: Lys-Ser-Pro-Glu-Glu-Leu-Lys-Gly-Ile-Phe-Glu-Lys-Tyr-Ala-Ala-Lys-Glu-Gly-Asp-Pro-Asn-Gln-Leu-Ser-Lys-Glu-Glu-Leu-Lys-Leu-Leu-Leu-Gln-Thr-Glu-Phe-Pro-Ser-Leu-Le u-Lys-Gly-Pro-Ser-Thr-Leu-Asp-Glu-Leu-Phe-Glu-Glu-Leu-Asp-Lys-Asn-Gly-Asp-Gly-Glu-Val-Ser-Phe-Glu-Glu-Phe-Gln-Val-Leu-Val-Lys-Lys-Ile-Ser-Gln-OH. It is a 75-residue protein (computed Mr = 8501), contains a single Tyr, and is devoid of Cys, Met, Trp, His, and Arg. The bulk of the sequence was determined by automated sequencing of: (i) the intact protein for 20 cycles; (ii) a large N-bromosuccinimide peptide for 37 cycles; (iii) a tryptic peptide (29 cycles), isolated by high performance liquid chromatography. Also described is a highly sensitive and rapid procedure for peptide mapping by high performance liquid chromatography.