Interactive forces between co-aggregating and non-co-aggregating oral bacterial pairs.
The temporo-spatial development of plaque is governed by adhesive interactions between different co-aggregating bacterial strains and species. Physico-chemically, these interactions are due to attractive Lifshitz-Van der Waals and acid-base forces, and occur despite electrostatic repulsion and with a critical influence of temperature. The forces between co-aggregating and non-co-aggregating pairs have never been measured, however. The aim here, thus, is to investigate, by atomic force microscopy, whether there is a difference in interactive forces between co-aggregating and non-co-aggregating bacterial pairs at 10 degrees C, 22 degrees C, and 40 degrees C. Actinomyces naeslundii 147 was immobilized on poly-L-lysine-coated tipless AFM cantilevers, while streptococci were immobilized on poly-L-lysine-coated glass surfaces. Upon approach, a repulsive force was measured, regardless of whether a co-aggregating or non-co-aggregating pair was involved. However, upon retraction, the co-aggregating pair exhibited larger adhesive forces and energies than did the non-co-aggregating pair. Adhesive interactions between the co-aggregating pair were smallest at 40 degrees C.
Department of Biomedical Engineering, University Medical Center Groningen, and University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
F
F
Postollec
W
W
Norde
J
J
de Vries
H J
HJ
Busscher
H C
HC
van der Mei
D000190:Actinomyces / Q000502:physiology; D000327:Adsorption; D001422:Bacterial Adhesion / Q000502:physiology*; D018625:Microscopy, Atomic Force; D019533:Streptococcus oralis / Q000502:physiology; D013298:Streptococcus sanguis / Q000502:physiology; D013499:Surface Properties