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A method for removing effects of nonspecific binding on the distribution of binding stoichiometries: application to mass spectroscopy data.

ABSTRACT: There is often an interest in knowing, for a given ligand concentration, how many protein molecules have one, two, three, etc. ligands bound in a specific manner. This is a question that cannot be addressed using conventional ensemble techniques. Here, a mathematical method is presented for separating specific from nonspecific binding in nonensemble studies. The method provides a way to determine the distribution of specific binding stoichiometries at any ligand concentration when using nonensemble (e.g., single-molecule) methods. The applicability of the method is demonstrated for ADP binding to creatine kinase using mass spectroscopy data. A major advantage of our method, which can be applied to any protein-ligand system, is that no previous information regarding the mechanism of ligand interaction is required.

SUBMITTER: Shimon L

PROVIDER: S-EPMC2931719 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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A method for removing effects of nonspecific binding on the distribution of binding stoichiometries: application to mass spectroscopy data.

Shimon Liat L Sharon Michal M Horovitz Amnon A

Biophysical journal 20100901 5

There is often an interest in knowing, for a given ligand concentration, how many protein molecules have one, two, three, etc. ligands bound in a specific manner. This is a question that cannot be addressed using conventional ensemble techniques. Here, a mathematical method is presented for separating specific from nonspecific binding in nonensemble studies. The method provides a way to determine the distribution of specific binding stoichiometries at any ligand concentration when using nonensem ...[more]

PMID: 20816078

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