The amino sequence of ovocleidin 17, a major protein of the avian eggshell calcified layer

Abstract

Note: The amino acid sequence reported in this paper has been submitted to the data bank of the Munich Information Centre for Protein Sequences with the accession number $78596 SUMMARYThe amino acid sequence of ovocleidin 17, a major protein of the chicken eggshell calcified layer, contains 142 amino acids including 2 phosphorylated serines. Data base searches show that ovocleidin belongs to a heterogeneous group of proteins consisting of a single C-type lectin domain (CTL). The most similar sequences with an average of 30% identical amino acids were those of pancreatic stone protein (lithostathine) and lectins and anticoagulant proteins from snake venom.

Chemical Biosensors Based on Proteins Involved in Biomineralization Processes

“…The resulting solution was injected into a Vydac C18 HPLC reverse phase column and eluted using a gradient of acetonitrile (100 %) with 0.1 % (v/v) TFA for 85 minutes at a rate flow of 1 mL min -1 . Along the purification step two proteins were observed, SCA-1 (Rt=58.765 min) at a higher concentration and SCA-2 (Rt=56.26 min) at a lower concentration as reported previously (Mann and Siedler, 1999). In the particular case of Ansocalcin, only one protein was obtained (Rt=58.0 min) using the same gradient as that reported for SCA-1 and SCA-2 adjusted to our experimental set up for chromatographic procedures.…”

“…Nowadays, an increasing number of studies in C-type lectin-like proteins contained in the avian eggshell matrix have been reported elsewhere (Drickamer, 1999) but they have not been considered as biological sensors for inorganic ions. In this way, Mann & Siedler have determined the amino acid sequence of OC-17, a major protein of the hen´s (Gallus gallus) eggshell (Mann & Siedler, 1999); later, struthiocalcin-1 and 2 (SCA-1 and SCA-2) present in ostrich (Struthio camelus) eggshell matrix (Mann & Siedler, 2004), and they have recently, elucidated the amino acid sequence of two proteins of emu (Dromaius novaehollandiae) dromaiocalcin-1 and 2 and two proteins in rhea (Rhea americana) rheacalcin-1 and 2 (Mann & Siedler, 2006). Mann suggested that the structure of the ostrich eggshell was very similar to that of avian eggshells; for example, ansocalcin had the same number of aminoacid sequences.…”

How does an amorphous surface influence molecular binding? – ovocleidin-17 and amorphous calcium carbonate

“…Taken together this evidence implies that the protein may be able to bind to ACC and stimulate its conversion to calcite and then detach -effectively operating as a catalyst. The promotion of crystallisation seems a plausible function for OC-17 given that it is found in high concentrations in the mamilary caps of eggshells, which is where crystallisation begins 11,12 .…”

Investigation of the role of ansocalcin in the biomineralization in goose eggshell matrix

“…Amino acid sequence homology of ansocalcin with other related proteins. Ovocleidin isolated from chicken eggshell (35), c-type lectin found from snake venom (36). The identical amino acid residues are shaded in black; asterisks indicate the pair of acid residues observed in ansocalcin.…”

“…A number of such biomacromolecules have been extracted, purified, and identified from the chicken eggshells (31)(32)(33)(34)(35)(36)(37)(38). These biomacromolecules, especially the matrix proteins, are believed to be active in controlling the morphology and selective nucleation of polymorphs of the CaCO 3 layer of the eggshell (39).…”