TY - JOUR T1 - Nuclear pore-like structures in a compartmentalized bacterium JF - bioRxiv DO - 10.1101/076430 SP - 076430 AU - Evgeny Sagulenko AU - Amanda Nouwens AU - Richard I. Webb AU - Kathryn Green AU - Benjamin Yee AU - Garry Morgan AU - Andrew Leis AU - Kuo-Chang Lee AU - Margaret K. Butler AU - Nicholas Chia AU - Uyen Thi Phuong Pham AU - Stinus Lindgreen AU - Ryan Catchpole AU - Anthony M. Poole AU - John A Fuerst Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/09/21/076430.abstract N2 - Planctomycetes are distinguished from other Bacteria by compartmentalization of cells via internal membranes, interpretation of which has been subject to recent debate regarding potential relations to Gram-negative cell structure. In our interpretation of the available data, the planctomycete Gemmata obscuriglobus contains a nuclear body compartment, and thus possesses a type of cell organization with parallels to the eukaryote nucleus. Here we show that pore-like structures occur in internal membranes of G.obscuriglobus and that they have elements structurally similar to eukaryote nuclear pores, including a basket, ring-spoke structure, and eight-fold rotational symmetry. Bioinformatic analysis of proteomic data reveals that some of the G. obscuriglobus proteins associated with pore-containing membranes possess structural domains found in eukaryote nuclear pore complexes. Moreover, immuno-gold labelling demonstrates localization of one such protein, containing a β-propeller domain, specifically to the G. obscuriglobus pore-like structures. Finding bacterial pores within internal cell membranes and with structural similarities to eukaryote nuclear pore complexes raises the dual possibilities of either hitherto undetected homology or stunning evolutionary convergence. ER -