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Enhancing Robustness of Sortase A by Loop Engineering and Backbone Cyclization.

ABSTRACT: Staphylococcus aureus sortase?A (SaSrtA) is widely used for site-specific protein modifications, but it lacks the robustness for performing bioconjugation reactions at elevated temperatures or in presence of denaturing agents. Loop engineering and subsequent head-to-tail backbone cyclization of SaSrtA yielded the cyclized variant CyM6 that has a 7.5?°C increased melting temperature and up to 4.6-fold increased resistance towards denaturants when compared to the parent rM4. CyM6 gained up to 2.6-fold (vs. parent rM4) yield of conjugate in ligation of peptide and primary amine under denaturing conditions.

SUBMITTER: Zou Z

PROVIDER: S-EPMC7693181 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Enhancing Robustness of Sortase A by Loop Engineering and Backbone Cyclization.

Zou Zhi Z Mate Diana M DM Nöth Maximilian M Jakob Felix F Schwaneberg Ulrich U

Chemistry (Weinheim an der Bergstrasse, Germany) 20200818 60

Staphylococcus aureus sortase A (SaSrtA) is widely used for site-specific protein modifications, but it lacks the robustness for performing bioconjugation reactions at elevated temperatures or in presence of denaturing agents. Loop engineering and subsequent head-to-tail backbone cyclization of SaSrtA yielded the cyclized variant CyM6 that has a 7.5 °C increased melting temperature and up to 4.6-fold increased resistance towards denaturants when compared to the parent rM4. CyM6 gained up to 2.6- ...[more]

PMID: 32649777

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