Erratum: “Characterization of two molluscan crystal‐modulating biomineralization proteins and identification of putative mineral binding domains”, vol. 70, no. 4, pp. 522–533 (2003)

Abstract

We wish to alert the reader to errors that were inadvertantly published in our recent article. First, in the Abstract, we incorrectly state that our CD experiments included Ca (II) ion titrations of AP7-1 and AP24-1 synthetic polypeptides; these Ca (II) titrations were withheld from the final draft of the paper and are not included in the published report, but will appear elsewhere. Secondly, in our AP7-1 and AP24-1 calcite overgrowth experiments, we incorrectly reported the concentrations utilized in our study under the Materials and Methods section subheading, "Crystal Growth Analysis." The correct concentrations utilized for AP7-1, AP24-1 should read as 1.65 ϫ 10 Ϫ6

Molecular Characterization of the 30-AA N-Terminal Mineral Interaction Domain of the Biomineralization Protein AP7

“…19 Finally, using a randomly scrambled version of the AP7-1 sequence (AP7-1s, AYV-QGNTDNADMDNGIRYSLLYNDTSLGSG), we probed the impact of the primary sequence on peptide-mediated in vitro crystal growth inhibition. 12,17,19 Our findings shed additional light on the nature of AP7-1 interactions with calcium carbonates: the AP7-1 sequence does interact with Ca(II), yet the global conformation of this sequence in solution is insensitive to Ca(II) binding, indicating that this polypeptide retains its unfolded structure in solution in the presence of Ca(II). Our MAS NMR studies indicate that AP7-1 does interact with calcium carbonate minerals in vitro, and this peptide is not easily displaced from the crystals.…”

“…In relevant model systems of polymorph stabilization, such as the Pacific red abalone (Haliotis rufescens), 11,12 sawtooth penshell (Atrina serrata), 15 and Japanese pearl oyster (Pinctada fucata), 16 aragonite is routinely synthesized to form mechanically strong nacre layers. It now appears that aragonite formation is under the control of protein superfamilies, 11,12,[15][16][17] and recent efforts have been devoted to the isolation, sequencing, and characterization of these interesting proteins. As part of this overall effort, we initiated molecular studies of the conformation and in vitro mineralization properties of 30 AA N-terminal sequences identified in the nacre-specific proteins, AP7 and AP24.…”

“…As part of this overall effort, we initiated molecular studies of the conformation and in vitro mineralization properties of 30 AA N-terminal sequences identified in the nacre-specific proteins, AP7 and AP24. 17,18 These mineral modification domains are dissimilar in primary sequence and exist as conformationally labile macromolecules with subtle structural differences in solution. 18 Yet, both N-terminal sequences exhibit strong similarities in their ability to interrupt calcium carbonate crystal growth in vitro.…”

“…18 Yet, both N-terminal sequences exhibit strong similarities in their ability to interrupt calcium carbonate crystal growth in vitro. 17 Ultimately, to understand the aragonite polymorph selection and stabilization process in H. rufescens, the interactive characteristics of these N-terminal mineral modification domains require further eludication.…”

“…Since one possible route for AP7 and AP24 protein interactions with calcium carbonates is via interaction with Ca(II) ions residing on exposed calcite interfaces, 17,18 it is critical to understand the AP7 and AP24 N-terminal domain interactions with Ca(II) itself and with growing calcium carbonate crystals. As a first step in this quest, we report here multidisciplinary studies of the 30 AA N-terminal domain of AP7 (AP7-1, DDNGNYGNGM-ASVRTQGNTYDDLASLISYL), wherein we investigated the Ca(II) interaction capability of this sequence and the effect of Ca(II) on polypeptide conformation.…”