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Detecting Differences in Prion Protein Conformation by Quantifying Methionine Oxidation.

ABSTRACT: A prion's pathogenic character is enciphered in its conformation, which also defines the chemical environments of its amino acids. Differences in chemical environments influence the reactivity of amino acid side chains, in a conformation-dependent manner. Chemical oxidation of susceptible methionines would identify those methionines on the surface of a prion, which would reveal conformation-dependent information. We identified a set of methionine-containing peptides derived from the tryptic, chymotryptic, or tryptic/chymotryptic digestion of recombinant prion protein and the Sc237 strain of hamster-adapted scrapie. We developed a multiple reaction monitoring-based method of quantifying the extent of the methionine oxidation in those peptides. This approach can be used to define a prion's conformation and to distinguish among prion strains, which is an important component of food safety.

SUBMITTER: Silva CJ

PROVIDER: S-EPMC8793083 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Detecting Differences in Prion Protein Conformation by Quantifying Methionine Oxidation.

Silva Christopher J CJ Erickson-Beltran Melissa M

ACS omega 20220107 3

A prion's pathogenic character is enciphered in its conformation, which also defines the chemical environments of its amino acids. Differences in chemical environments influence the reactivity of amino acid side chains, in a conformation-dependent manner. Chemical oxidation of susceptible methionines would identify those methionines on the surface of a prion, which would reveal conformation-dependent information. We identified a set of methionine-containing peptides derived from the tryptic, chy ...[more]

PMID: 35097263

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