Figure 3

The D1D3 domain is sufficient for polar localization. A. Models of the oligomerization status of TnaA and the subdomain constructs. The four subunits in the TnaA tetramer are designated as TnaA¹, TnaA², TnaA³ and TnaA⁴. The deleted subdomains were removed from the TnaA tetrameric crystal structure (PDB 2OQX). The positions of the D1 (magenta), D2 (grey) and D3 (pink) subdomains in TnaA are illustrated in the upper right molecule of the tetramer. The other three TnaA molecules that make up the tetramer are shown in blue, cyan and orange. The four catalytic pockets are located at the left and right sides of the tetramer, and are not visible in this view. B. Protein stability of the subdomain constructs. E. coli strains expressing each TnaA truncation mutant were grown in LB to an OD₆₀₀ of 1.0 and analyzed by SDS-PAGE. The sfGFP fusion proteins were visualized by in-gel GFP fluorescence imaging. The top-most band in each lane represents the expected size of the respective full-length fusion protein. C. Cellular localization of the subdomain constructs. GFP and phase contrast images are overlaid.