Abstract: The present invention disclosed the cloning and the purification of a mutant of prethrombin-2, which contains a thrombin cleavage site instead of a factor Xa cleavage site. The stable mutant prethrombin-2 is able to convert itself autocatalytically into active ?-thrombin in the absence of ecarin or factor Xa. The new concept of signal amplification using self-replicating enzymes can be applied to improve sensitivity of ?-thrombin assays and also for the preparation of different enzymes.

Abstract: The present invention provides a container and a method that can be used to transport and store AFM probes in a liquid buffer. This container fastens an AFM probe and consists of a plastic lid that secures a probe while keeping it in a controlled environment, thus preventing that the tips are contaminated by air-borne molecules, packaging material, deposited substances or air bubbles. In the case of functionalized probes, the surface molecules are still functional upon arrival. The tips cannot be broken upon transport because they are held by the container, however the probes can be easily removed upon opening of the container.