The molecular mechanism by which swimming bacteria are propelled through liquid media by rotating flagella is understood relatively well. Gliding motility (movement of cells over surfaces without the aid of flagella) is a trait common to many bacteria, yet the mechanisms responsible for gliding motility are poorly understood. My lab uses the techniques of genetics, molecular biology, biochemistry, and microscopy to determine the mechanism of Flavobacterium johnsoniae gliding motility. We developed techniques to allow genetic manipulation of this organism, and have used these techniques to isolate nonmotile mutants and to identify the genes that are altered in these mutants. These genes code for proteins that make up the gliding motility apparatus ('motor') that propels the cells. We use antibodies raised against these proteins to localize the components of the motor, determine how they interact, and visualize the gliding motility apparatus in cells. Based on our results we have developed a model for Flavobacterium gliding that involves the active movement of adhesive fibrils along the cell surface. We also identified a novel protein secretion system that is involved in assembly of the motility apparatus.
In addition to studies on gliding motility, we are also investigating other aspects of the biology of gliding bacteria. These bacteria are abundant in many environments and some have characteristics that make them important organisms to study. Examples of applied projects include studies of chitin digestion by F. johnsoniae, studies of cellulose digestion by Cytophaga hutchinsonii, and genetic analysis of the fish pathogens Flavobacterium psychrophilum and Flavobacterium columnare.
Hoikkala, V., Ravantti, J., Díez-Villaseñor, C., Tiirola, M., Conrad, Rachel A., McBride, Mark J., Moineau, S., and Sundberg, Lotta R.
“Cooperation between different CRISPR-Cas types enables adaptation in an RNA-targeting system” mBio12. (2021): e03338-20.
Lorencik, Katarzyna, Ekiert, Robert, Zhu, Yongtao, McBride, Mark J., Gennis, Robert B., Sarewicz, Marcin, and Osyczka, Artur.
“The monoheme c subunit of respiratory alternative complex III is not essential for electron transfer to cytochrome aa3 in Flavobacterium johnsoniae” Microbiology Spectrum9. (2021): e00135-21.
Barbier, Paul, Rochat, Tatiana, Mohammed, Haitham H., Wiens, Gregory D., Bernardet, Jean-Francois, Halpern, David, Duchaud, Eric, and McBride, Mark J.
“The type IX secretion system is required for virulence of the fish pathogen Flavobacterium psychrophilum” Applied and Environmental Microbiology86. (2020): 1-22.
Ficko-Blean, E, Préchoux, A, Thomas, F, Rochat, T, Larocque, R, Zhu, Y, Stam, M, Génicot, S, Jam, M, Calteau, A, Viart, B, Ropartz, D, Pérez-Pascual, D, Correc, G, Matard-Mann, M, Stubbs, K A., Rogniaux, H, Jeudy, A, Barbeyron, T, Médigue, C, Czjzek, M, Vallenet, D, McBride, Mark J., Duchaud, E, and Michel, G.
“Carrageenan catabolism is encoded by a complex regulon in marine heterotrophic bacteria” Nature communications8.1 (2017): 1685.
Li , N, Zhu, Y, LaFrentz, B R., Evenhuis, J P., Hunnicutt, D W., Conrad, R A., Barbier, P, Gullstrand, C W., Roets, J E., Powers, J L., Kulkarni, S S., Erbes, D H., García, J C., Nie, P, and McBride, Mark J.
“The Type IX Secretion System Is Required for Virulence of the Fish Pathogen Flavobacterium columnare” Applied and environmental microbiology83.23 (2017).
Zhu, Y, Thomas, F, Larocque, R, Li , N, Duffieux, D, Cladière, L, Souchaud, F, Michel, G, and McBride, Mark J.
“Genetic analyses unravel the crucial role of a horizontally acquired alginate lyase for brown algal biomass degradation by Zobellia galactanivorans” Environmental microbiology19. (2017): 2164-2181.
Larsbrink, Johan , Zhu, Yongtao, Kharade, Sampada S., Kwiatkowski, Kurt J., Eijsink, Vincent G., Koropatkin, Nicole M., McBride, Mark J., and Pope, Philip B.
“A polysaccharide utilization locus from Flavobacterium johnsoniae enables conversion of recalcitrant chitin” Biotechnology for Biofuels9.260 (2016): 16.
Zhu, Yongtao, Han, Lanlan, Hefferon, Kathleen L., Silvaggi, Nicholas R., Wilson, David B., and McBride, Mark J.
“Periplasmic Cytophaga hutchinsonii endoglucanases are required for use of crystalline cellulose as sole carbon and energy source” Applied and Environmental Microbiology82.15 (2016): 4835-4845.
Li , N, Qin, T, Zhang, X L., Huang, B, Liu, Z X., Xie, H X., Zhang, J, McBride, Mark J., and Nie, P.
“Gene deletion strategy to examine the involvement of the two chondroitin lyases in Flavobacterium columnare virulence” Applied and environmental microbiology81.21 (2015): 7394-402.
McBride, Mark J., Liu, Weifeng, Lu, Xuemei, Zhu, Yongtao, and Zhang, Weixin.
“The family Cytophagaceae” The Prokaryotes11.4 Ed. Rosenberg, E., Stackebrandt, E., DeLong, E., Lory, S., and Thompson, F. L.Springer. (2014): 577-593.
