1. Chemical Force Spectroscopy on single living cells E. Dague, D. Alsteens, J.P. Latgé, Y. Dufrêne

2. Kaminsky et al., 2006. Mycological Research Aspergillus hyphae and conidia as seen by SEM

3. Classical way of probing microbial hydrophobicity Hydrophobicity – MATH, MATS – HIC – Adhesion test – Contact angle Not specific of hydrophobic character and under electrostatic interactions influence (Mozes, Rouxhet 1987 ; van Loosdrecht et al., 1990 ; Gaboriaud et al., 2006) vortex 1 min

4. Increasing CH 3 surface fraction Probing hydrophobic forces at the nanoscale

5. Alsteens, Dague et al., Langmuir 2007 0246810 0 20 30 100 % CH 3 75 % CH 3 50 % CH 3 25 % CH 3 0 % CH 3 Frequency (%) Adhesion force (nN) Hydrophobicity calibration Hydrophobicity quantification and calibration 020406080100 0 2 4 6 8 10 Surface fraction CH 3 (%) 020406080100 0 2 4 6 8 10 Adhesion force (nN) 3 (%)

6. Single Aspergillus conidia trapped in a pore as seen by contact mode AFM 500 nm sample holder membrane water single cell tape

7. 100 nm 1000 pN 0 1 2 3 4 5 Adhesion force (pN) 0100020003000400050006000 Hydrophobic Force Microscopy of A. fumigatus Frequency (%) Dal : native 100 nm

8. Dal : native Dal + NaOH 1M 100 nm

9. Dal : native Dal + NaOH 1M Mutant without hydrophobins 100 nm Dague, Alsteens et al., Nanoletters 2007

10. 100 nm

11. Adhesion force map revealing highly correlated structural and hydrophobic heterogeneities 100 nm Dague, Alsteens et al., Nanoletters 2007

12. Kaminsky et al., 2006. Mycological Research Aspergillus hyphae and conidia as seen by SEM

13. Germination Real time imaging of conidia during germination Dague et al., Biophysical Journal 2007

14. 0 min 20 min 120 min180 min 60 min 120 min 200 nm Structural dynamics of single germinating conidia

15. 0 min 60 min 180 min 90 min 120 min 210 min 100 nm 200 nm 100 nm 200nm 100 nm Evolution of hydrophobicity with germination time Dague et al., Biophysical Journal 2007

16. Hydrophobicity can be probed and quantified at the nanoscale Direct visualization of correlated morphological and chemical evolution Biological process (germination), chemical modifications can be observed, in real time Take Home Message

17. Y. DufrêneD. AlsteensJ.P. Latgé

18. Chemical Force Spectroscopy on single living cells E. Dague, D. Alsteens, J.P. Latgé, Y. Dufrêne

19. Toward a global bio-surface analysis : Combined use of AFM, XPS and SIMS Dague et al., Langmuir 2008 AB CD Dal Rod B Rod A Rod AB Intensity (a. u.) XPS N peak 0.00 0.01 0.02 WT ∆RodB ∆RodA∆RodA ∆RodB Normalized intensities i/i tot C 2 H 3 O 2 - NI, SIMS CN - NI, SIMS