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Uranyl Photocleavage of Phosphopeptides Yields Truncated C-Terminally Amidated Peptide Products.

ABSTRACT: The uranyl ion (UO₂²⁺ ) binds phosphopeptides with high affinity, and when irradiated with UV-light, it can cleave the peptide backbone. In this study, high-accuracy tandem mass spectrometry and enzymatic assays were used to characterise the photocleavage products resulting from the uranyl photocleavage reaction of a tetraphosphorylated ?-casein model peptide. We show that the primary photocleavage products of the uranyl-catalysed reaction are C-terminally amidated. This could be of great interest to the pharmaceutical industry, as efficient peptide amidation reactions are one of the top challenges in green pharmaceutical chemistry.

SUBMITTER: Elnegaard RLB

PROVIDER: S-EPMC5488209 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Uranyl Photocleavage of Phosphopeptides Yields Truncated C-Terminally Amidated Peptide Products.

Elnegaard Rasmus L B RLB Møllegaard Niels Erik NE Zhang Qiang Q Kjeldsen Frank F Jørgensen Thomas J D TJD

Chembiochem : a European journal of chemical biology 20170523 12

The uranyl ion (UO<sub>2</sub><sup>2+</sup> ) binds phosphopeptides with high affinity, and when irradiated with UV-light, it can cleave the peptide backbone. In this study, high-accuracy tandem mass spectrometry and enzymatic assays were used to characterise the photocleavage products resulting from the uranyl photocleavage reaction of a tetraphosphorylated β-casein model peptide. We show that the primary photocleavage products of the uranyl-catalysed reaction are C-terminally amidated. This co ...[more]

PMID: 28425166

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