Axial asymmetry organizes division plane orthogonality inNeisseria gonorrhoeae

Abstract

For rod-shaped bacterial model organisms, the division plane is defined by the geometry of the cell. However, forNeisseria gonorrhoeae, a coccoid organism that most commonly exists as a diplococcus and that possesses genes coding for rod-based cell division systems, the relationship between cell geometry and division is unclear. Here, we characterized the organization ofN. gonorrhoeaedivision using a combination of fluorescent probes, genetics, and time-lapse microscopy. We found that the planes of successive cell divisions are orthogonal and temporally overlapping, thereby maintaining diplococcal morphology. Division takes place perpendicular to a subtle long-axis in each coccus. In keeping with the ParABS and the MinCDE systems reading the long-axis of rod-shaped bacteria, in the coccoidN. gonorrhoeae, ParB segregates along this subtle long-axis and cells lackingminCDEhave severe morphological consequences, including an inability to perform orthogonal division and aberrant assembly of the division plane at the cell poles. Taken together, this stresses the central role of even slight dimensional asymmetry as a general organizational principle in bacterial cell division.