Physiochemical properties of Caulobacter crescentus holdfast: a localized bacterial adhesive.
To colonize surfaces, the bacterium Caulobacter crescentus employs a polar polysaccharide, the holdfast, located at the end of a thin, long stalk protruding from the cell body. Unlike many other bacteria which adhere through an extended extracellular polymeric network, the holdfast footprint area is tens of thousands times smaller than that of the total bacterium cross-sectional surface, making for some very demanding adhesion requirements. At present, the mechanism of holdfast adhesion remains poorly understood. We explore it here along three lines of investigation: (a) the impact of environmental conditions on holdfast binding affinity, (b) adhesion kinetics by dynamic force spectroscopy, and (c) kinetic modeling of the attachment process to interpret the observed time-dependence of the adhesion force at short and long time scales. A picture emerged in which discrete molecular units called adhesins are responsible for initial holdfast adhesion, by acting in a cooperative manner.
Department of Biology, Indiana University , Bloomington, Indiana 47405, United States.
Cécile
C
Berne
Xiang
X
Ma
Nicholas A
NA
Licata
Bernardo R A
BR
Neves
Sima
S
Setayeshgar
Yves V
YV
Brun
Bogdan
B
Dragnea
D001422:Bacterial Adhesion; D016935:Caulobacter crescentus / Q000502:physiology*; D005898:Glass / Q000737:chemistry; D006834:Hydrazines / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D009994:Osmolar Concentration; D013499:Surface Properties; D014909:Wheat Germ Agglutinins / Q000737:chemistry / Q000378:metabolism
C417561:Alexa 488 hydrazide; D006834:Hydrazines; D014909:Wheat Germ Agglutinins