Cloning and characterization of four novel coral acid-rich proteins that precipitate carbonates in vitro

Tali Mass, Jeana L. Drake, Liti Haramaty, J. Dongun Kim, Ehud Zelzion, Debashish Bhattacharya, Paul G. Falkowski

نتاج البحث: نشر في مجلةمقالةمراجعة النظراء

ملخص

Biomineralization is a widely dispersed and highly regulated but poorly understood process by which organisms precipitate minerals from a wide variety of elements [1]. For many years, it has been hypothesized that the biological precipitation of carbonates is catalyzed by and organized on an extracellular organic matrix containing a suite of proteins, lipids, and polysaccharides [2, 3]. The structures of these molecules, their evolutionary history, and the biophysical mechanisms responsible for calcification remain enigmatic. Despite the recognition that mineralized tissues contain proteins that are unusually rich in aspartic and glutamic acids [4-6], the role of these proteins in biomineralization remains elusive [5, 6]. Here we report, for the first time, the identification, cloning, amino acid sequence, and characterization of four highly acidic proteins, derived from expression of genes obtained from the common stony coral, Stylophora pistillata. Each of these four proteins can spontaneously catalyze the precipitation of calcium carbonate in vitro. Our results demonstrate that coral acid-rich proteins (CARPs) not only bind Ca 2+ stoichiometrically but also precipitate aragonite in vitro in seawater at pH 8.2 and 7.6, via an electrostatic interaction with protons on bicarbonate anions. Phylogenetic analysis suggests that at least one of the CARPs arose from a gene fusion. Similar, highly acidic proteins appear to have evolved several times independently in metazoans through convergence. Based purely on thermodynamic grounds, the predicted change in surface ocean pH in the next decades would appear to have minimal effect on the capacity of these acid-rich proteins to precipitate carbonates.

اللغة الأصليةإنجليزيّة أمريكيّة
الصفحات (من إلى)1126-1131
عدد الصفحات6
دوريةCurrent Biology
مستوى الصوت23
رقم الإصدار12
المعرِّفات الرقمية للأشياء
حالة النشرنُشِر - 17 يونيو 2013
منشور خارجيًانعم

All Science Journal Classification (ASJC) codes

  • !!General Biochemistry, Genetics and Molecular Biology
  • !!General Agricultural and Biological Sciences

بصمة

أدرس بدقة موضوعات البحث “Cloning and characterization of four novel coral acid-rich proteins that precipitate carbonates in vitro'. فهما يشكلان معًا بصمة فريدة.

قم بذكر هذا