Perlwapin, an abalone nacre protein with three four-disulfide core (whey acidic protein) domains, inhibits the growth of calcium carbonate crystals
Perlwapin, an abalone nacre protein with three four-disulfide core (whey acidic protein) domains, inhibits the growth of calcium carbonate crystals
复制标题
DOI：
10.1529/biophysj.106.086108
复制
发表时间：
2006-10-01
影响因子：
3.4
通讯作者：
Fritz, Monika
中科院分区：
文献类型：
--
作者：
Treccani, Laura;Mann, Karlheinz;Fritz, Monika
我们从鲍鱼壳的珍珠层中分离到一种新的蛋白质。氨基酸序列分析表明，该蛋白质由134个氨基酸组成，并含有三个重复序列; 40个氨基酸，这是非常相似的其他蛋白质的众所周知的乳清酸性蛋白结构域。因此，这种新的蛋白质被命名为perlwapin。除了主要序列外，我们还发现了几个次要变异。用原子力显微镜研究了perlwapin与方解石晶体的相互作用。方解石晶体的单分子层在去离子水中溶解非常缓慢，并在过饱和碳酸钙溶液中重结晶。当Perlwapin溶解在过饱和碳酸钙溶液中时，晶体的生长立即受到抑制。Perlwapin分子紧密地结合在不同的台阶边缘，阻止晶体层生长。使用较低浓度的perlwapin在饱和碳酸钙溶液中，我们可以区分天然的，活性perlwapin分子从变性的。这些观察结果表明，perlwapin可以作为碳酸钙晶体在饱和碳酸钙溶液中的生长抑制剂。珍珠华平在珍珠层生长中的功能可以是抑制聚合物/矿物复合珍珠层的矿物相中某些晶面的生长。
We have isolated a new protein from the nacreous layer of the shell of the sea snail Haliotis laevigata (abalone). Amino acid sequence analysis showed the protein to consist of 134 amino acids and to contain three sequence repeats of; 40 amino acids which were very similar to the well-known whey acidic protein domains of other proteins. The new protein was therefore named perlwapin. In addition to the major sequence, we identified several minor variants. Atomic force microscopy was used to explore the interaction of perlwapin with calcite crystals. Monomolecular layers of calcite crystals dissolve very slowly in deionized water and recrystallize in supersaturated calcium carbonate solution. When perlwapin was dissolved in the supersaturated calcium carbonate solution, growth of the crystal was inhibited immediately. Perlwapin molecules bound tightly to distinct step edges, preventing the crystal layers from growing. Using lower concentrations of perlwapin in a saturated calcium carbonate solution, we could distinguish native, active perlwapin molecules from denaturated ones. These observations showed that perlwapin can act as a growth inhibitor for calcium carbonate crystals in saturated calcium carbonate solution. The function of perlwapin in nacre growth may be to inhibit the growth of certain crystallographic planes in the mineral phase of the polymer/mineral composite nacre.