Appeal No. 1998-0053
Application 08/444,628
domain homologous to the "-2 chain of type V collagen. The metalloproteinases are
4
secreted as zymogens, and undergo activation extracellularly through amino-terminal
proteolytic processing. Once activated, the 92 kDa gelatinase, as its name indicates, has
the ability to degrade gelatin (denatured collagen); it also degrades insoluble elastin.
There are three other metalloproteinases with the ability to degrade insoluble elastin: the
72 kDa gelatinase, matrilysin and macrophage metalloelastase. Specification, pages 2
and 3; Goldberg, columns 1 and 2, and Figure 6.
DISCUSSION
Claim 1 is directed to a truncation mutant representing the zinc-binding catalytic
domain of the 92 kDa gelatinase, but lacking the three fibronectin-like type II repeats
normally present in the catalytic domain of the parent enzyme. Claim 4 is directed to a
method of making the truncation mutant. The truncation mutant consists of amino acid
residues 106-216 fused to residues 391-443 of the parent molecule. In other words, the
truncated protein is distinguished from the parent enzyme by three separate deletions:
amino-terminal residues 1-105, internal residues 217-390, and carboxy-terminal residues
444-707. According to the specification, the truncation mutant is catalytically active
against gelatin, but, unlike the parent enzyme, inactive against insoluble elastin.
Specification, page 3.
4A zymogen is an inactive enzyme precursor, also known as a proenzyme.
4
Page: Previous 1 2 3 4 5 6 7 8 9 Next
Last modified: November 3, 2007