---

Why do we need single DNA molecule handling and restriction analysis?

• Understanding how an enzyme molecule finds its restriction site on a DNA molecule
  
• How bind restriction enzyme molecules to a DNA molecule?
• How can an enzyme molecule move along the DNA to find its restriction site?
• Understanding of the enormous individuality and variability of DNA
• Development of a single molecule DNA analysis
  

Development of a spatial and temporal resolved restriction analysis of single DNA molecules

---

Experimental set-up:

---

DNA handling:

---

Free motion, stretching and relaxation of a lambda-DNA molecule:

---

Restriction of an individual lambda-DNA molecule with the endonuclease Apa I:

Restriction map of Apa I on lambda-DNA:

---

Stepwise restriction of a DNA molecule with Sma I in realtime (25 frames/sec):

Restriction map of Sma I on lambda-DNA:

---

Slower version of the Sma I restriction (10 frames/sec):

---