title: Nanoscale imaging of Bacillus thuringiensis flagella using atomic force microscopy.
abstract: Because bacterial flagella play essential roles in various processes (motility, adhesion, host interactions, secretion), studying their expression in relation to function is an important challenge. Here, we use atomic force microscopy (AFM) to gain insight into the nanoscale surface properties of two wild-type and four mutant strains of Bacillus thuringiensis exhibiting various levels of flagellation. We show that, unlike AFM in liquid, AFM in air is a simple and reliable approach to observe the morphological details of the bacteria, and to quantify the density and dimensions of their flagella. We found that the amount of flagella expressed by the six strains, as observed at the nanoscale, correlates with their microscopic swarming motility. These observations provide novel information on flagella expression in gram-positive bacteria and demonstrate the power of AFM in genetic studies for the fast assessment of the phenotypic characteristics of bacterial strains altered in cell surface appendages.
authors.affiliation: Laboratory of Food and Environmental Microbiology, Earth and Life Institute, Université catholique de Louvain, Croix du Sud 2, Box L7.05.12, B-1348, Louvain-la-Neuve, Belgium.
authors.forename: Annika
authors.initials: A
authors.lastname: Gillis
authors.forename: Vincent
authors.initials: V
authors.lastname: Dupres
authors.forename: Guillaume
authors.initials: G
authors.lastname: Delestrait
authors.forename: Jacques
authors.initials: J
authors.lastname: Mahillon
authors.forename: Yves F
authors.initials: YF
authors.lastname: Dufrêne
mesh_terms: D000388:Air; D001413:Bacillus thuringiensis / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure*; D005407:Flagella / Q000648:ultrastructure*; D018625:Microscopy, Atomic Force; D012996:Solutions / Q000737:chemistry; D013499:Surface Properties
chemical_list: D012996:Solutions