Ankyrin repeats as a dimerization module

作者：Kozlov Guennadi; Wong Kathy; Wang Wenxuan; Skubak Pavol; Munoz Escobar Juliana; Liu Yue; Siddiqui Nadeem; Pannu Navraj S; Gehring Kalle^*

来源：Biochemical and Biophysical Research Communications, 2018, 495(1): 1002-1007.

DOI：10.1016/j.bbrc.2017.11.135

• LegA12
• lpg0483
• X-ray crystallography
• Virulence factor
• Pathogen

Legionella pneumophila is a pathogen, causing severe pneumonia in humans called Legionnaires' disease. AnkC (LegA12) is a poorly characterized 495-residue effector protein conserved in multiple Legionella species. Here, we report the crystal structure of a C-terminally truncated AnkC (2-384) at 3.2 angstrom resolution. The structure shows seven ankyrin repeats (ARs) with unique structural features. AnkC forms a dimer along the outer surface of loops between ARs. The dimer exists both in the crystal form and in solution, as shown by analytical ultracentrifugation. This is the first example of ARs as a dimerization module as opposed to solely a protein interaction domain. In addition, a novel alpha-helix insert between AR3-AR4 is positioned across the surface opposite the ankyrin groove. Sequence conservation suggests that the ankyrin groove of AnkC is a functional site that interacts with binding targets. This ankyrin domain structure is an important step towards a functional characterization of AnkC.

• 出版日期2018-1-1
• 单位McGill