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Scaling Concepts in Serpin Polymer Physics.

ABSTRACT: α1-Antitrypsin is a protease inhibitor belonging to the serpin family. Serpin polymerisation is at the core of a class of genetic conformational diseases called serpinopathies. These polymers are known to be unbranched, flexible, and heterogeneous in size with a beads-on-a-string appearance viewed by negative stain electron microscopy. Here, we use atomic force microscopy and time-lapse dynamic light scattering to measure polymer size and shape for wild-type (M) and Glu342→Lys (Z) α1-antitrypsin, the most common variant that leads to severe pathological deficiency. Our data for small polymers deposited onto mica and in solution reveal a power law relation between the polymer size, namely the end-to-end distance or the hydrodynamic radius, and the polymer mass, proportional to the contour length. We use the scaling concepts of polymer physics to assess that α1-antitrypsin polymers are random linear chains with a low persistence length.

SUBMITTER: Raccosta S

PROVIDER: S-EPMC8156723 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Scaling Concepts in Serpin Polymer Physics.

Raccosta Samuele S Librizzi Fabio F Jagger Alistair M AM Noto Rosina R Martorana Vincenzo V Lomas David A DA Irving James A JA Manno Mauro M

Materials (Basel, Switzerland) 20210515 10

α1-Antitrypsin is a protease inhibitor belonging to the serpin family. Serpin polymerisation is at the core of a class of genetic conformational diseases called serpinopathies. These polymers are known to be unbranched, flexible, and heterogeneous in size with a beads-on-a-string appearance viewed by negative stain electron microscopy. Here, we use atomic force microscopy and time-lapse dynamic light scattering to measure polymer size and shape for wild-type (M) and Glu342→Lys (Z) α1-antitrypsin ...[more]

PMID: 34063488

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