Flagella stator homologs function as motors for myxobacterial gliding motility by moving in helical trajectories

Significance Gliding is a form of enigmatic bacterial surface motility that does not use visible external structures such as flagella or pili. This study characterizes the single-molecule dynamics of the Myxococcus xanthus gliding motor protein AglR, a homolog of the Escherichia coli flagella stator protein MotA. However, the Myxococcus motors, unlike flagella stators, lack peptidoglycan-binding domains. With photoactivatable localization microscopy (PALM), we found that these motor proteins move actively within the cell membrane and generate torque by accumulating in clusters that exert force on the gliding surface. Our model unifies gliding and swimming with conserved power-generating modules. Many bacterial species use gliding motility in natural habitats because external flagella function poorly on hard surfaces. However, the mechanism(s) of gliding remain elusive because surface motility structures are not apparent. Here, we characterized the dynamics of the Myxococcus xanthus gliding motor protein AglR, a homolog of the Escherichia coli flagella stator protein MotA. We observed that AglR decorated a helical structure, and the AglR helices rotated when cells were suspended in liquid or when cells moved on agar surfaces. With photoactivatable localization microscopy, we found that single molecules of AglR, unlike MotA/MotB, can move laterally within the membrane in helical trajectories. AglR slowed down transiently at gliding surfaces, accumulating in clusters. Our work shows that the untethered gliding motors of M. xanthus, by moving within the membrane, can transform helical motion into linear driving forces that push against the surface.

[1]  Mingzhai Sun,et al.  Motor-driven intracellular transport powers bacterial gliding motility , 2011, Proceedings of the National Academy of Sciences.

[2]  T. Mignot,et al.  Bacterial motility complexes require the actin‐like protein, MreB and the Ras homologue, MglA , 2010, The EMBO journal.

[3]  Erinna F. Lee,et al.  Evidence That Focal Adhesion Complexes Power Bacterial Gliding Motility , 2022 .

[4]  D. Zusman,et al.  Chemosensory signaling controls motility and subcellular polarity in Myxococcus xanthus. , 2012, Current opinion in microbiology.

[5]  S. Kojima,et al.  Conformational change in the stator of the bacterial flagellar motor. , 2001, Biochemistry.

[6]  G. Oster,et al.  On the Mysterious Propulsion of Synechococcus , 2012, PloS one.

[7]  O. Sliusarenko,et al.  High‐throughput, subpixel precision analysis of bacterial morphogenesis and intracellular spatio‐temporal dynamics , 2011, Molecular microbiology.

[8]  D. B. Kearns,et al.  A field guide to bacterial swarming motility , 2010, Nature Reviews Microbiology.

[9]  V. Fromion,et al.  Processive Movement of MreB-Associated Cell Wall Biosynthetic Complexes in Bacteria , 2011, Science.

[10]  P. Youderian,et al.  Identification of genes required for adventurous gliding motility in Myxococcus xanthus with the transposable element mariner , 2003, Molecular microbiology.

[11]  D. Zusman,et al.  Isolation of bacteriophage MX4, a generalized transducing phage for Myxococcus xanthus. , 1978, Journal of molecular biology.

[12]  Adrien Ducret,et al.  Wet-surface–enhanced ellipsometric contrast microscopy identifies slime as a major adhesion factor during bacterial surface motility , 2012, Proceedings of the National Academy of Sciences.

[13]  Suliana Manley,et al.  Photoactivatable mCherry for high-resolution two-color fluorescence microscopy , 2009, Nature Methods.

[14]  Ryan G. Rhodes,et al.  Flavobacterium johnsoniae RemA Is a Mobile Cell Surface Lectin Involved in Gliding , 2012, Journal of bacteriology.

[15]  K. Ottemann,et al.  Motility and chemotaxis in Campylobacter and Helicobacter . , 2011, Annual review of microbiology.

[16]  Michael Unser,et al.  Automatic tracking of individual fluorescence particles: application to the study of chromosome dynamics , 2005, IEEE Transactions on Image Processing.

[17]  Beiyan Nan,et al.  A multi‐protein complex from Myxococcus xanthus required for bacterial gliding motility , 2010, Molecular microbiology.

[18]  D. Blair,et al.  Membrane segment organization in the stator complex of the flagellar motor: implications for proton flow and proton-induced conformational change. , 2008, Biochemistry.

[19]  Beiyan Nan,et al.  Uncovering the mystery of gliding motility in the myxobacteria. , 2011, Annual review of genetics.

[20]  N. Wingreen,et al.  The bacterial actin MreB rotates, and rotation depends on cell-wall assembly , 2011, Proceedings of the National Academy of Sciences.

[21]  X. Zhuang,et al.  Coupled, Circumferential Motions of the Cell Wall Synthesis Machinery and MreB Filaments in B. subtilis , 2011, Science.

[22]  John R. Kirby,et al.  Chemosensory pathways, motility and development in Myxococcus xanthus , 2007, Nature Reviews Microbiology.

[23]  Rym Agrebi,et al.  Emergence and Modular Evolution of a Novel Motility Machinery in Bacteria , 2011, PLoS genetics.

[24]  L. Søgaard-Andersen,et al.  Comprehensive Set of Integrative Plasmid Vectors for Copper-Inducible Gene Expression in Myxococcus xanthus , 2012, Applied and Environmental Microbiology.

[25]  D. Kaiser,et al.  Myxococcus cells respond to elastic forces in their substrate. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[26]  Emilia M F Mauriello,et al.  AglZ regulates adventurous (A‐) motility in Myxococcus xanthus through its interaction with the cytoplasmic receptor, FrzCD , 2009, Molecular microbiology.

[27]  E. Hoiczyk,et al.  Characterization of myxobacterial A‐motility: insights from microcinematographic observations , 2013, Journal of basic microbiology.

[28]  Jing Chen,et al.  Myxobacteria gliding motility requires cytoskeleton rotation powered by proton motive force , 2011, Proceedings of the National Academy of Sciences.