Crystal structure of a caricain D158E mutant in complex with E-64.
The structure of the D158E mutant of caricain (previously known as papaya protease omega) in complex with E-64 has been determined at 2.0 A resolution (overall R factor 19.3%). The structure reveals that the substituted glutamate makes the same pattern of hydrogen bonds as the aspartate in native caricain. This was not anticipated since in the native structure there is insufficient room to accommodate the glutamate side chain. The glutamate is accommodated in the mutant by a local expansion of the structure demonstrating that small structural changes are responsible for the change in activity.
Katerelos
N A
NA
Institute of Food Research, Reading Laboratory, UK.
Taylor
M A
MA
Scott
M
M
Goodenough
P W
PW
Pickersgill
R W
RW
D018360:Crystallography, X-Ray; D003546:Cysteine Endopeptidases / Q000737:chemistry* / Q000235:genetics; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry*; D018698:Glutamic Acid / Q000737:chemistry; D007930:Leucine / Q000031:analogs & derivatives* / Q000737:chemistry; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D010940:Plant Proteins; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics
D015853:Cysteine Proteinase Inhibitors; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D018698:Glutamic Acid; D003546:Cysteine Endopeptidases; C039974:caricain; D007930:Leucine; C024974:E 64