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Mutational probing of protein aggregates to design aggregation-resistant proteins.

ABSTRACT: Characterization of amorphous protein aggregates may offer insights into the process of aggregation. Eleven single amino acid mutants of lipase (LipA of Bacillus subtilis) were subjected to temperature-induced aggregation, and the resultant aggregates were characterized for recovery of activity in the presence of guanidinium chloride (GdmCl). Based on activity recovery profiles of the aggregates, the mutants could be broadly assigned into four groups. By including at least one mutation from each group, a mutant was generated that showed an increase of ~ 10 °C in melting temperature (T m) compared to the wild-type and did not aggregate even at 75 °C. This method explores characterization of amorphous protein aggregates in the presence of GdmCl and helps in identifying mutations involved in protein aggregation.

SUBMITTER: Kamal MZ

PROVIDER: S-EPMC4821347 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Mutational probing of protein aggregates to design aggregation-resistant proteins.

Kamal Mohamad Zahid MZ Kumar Virender V Satyamurthi Kundarapu K Das Kushal Kumar KK Rao Nalam Madhusudhana NM

FEBS open bio 20160104 2

Characterization of amorphous protein aggregates may offer insights into the process of aggregation. Eleven single amino acid mutants of lipase (LipA of Bacillus subtilis) were subjected to temperature-induced aggregation, and the resultant aggregates were characterized for recovery of activity in the presence of guanidinium chloride (GdmCl). Based on activity recovery profiles of the aggregates, the mutants could be broadly assigned into four groups. By including at least one mutation from each ...[more]

PMID: 27239434

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