[Mutants of subtilisin E].
Ser 236, located in the surface of subtilisin E and at the end of alpha-helex with Ser221, is far from the active center (Asp32, His64, Ser221). The replacement of Ser236 with Cys via directed-mutagenesis should effect protease activity insignificantly and may be able to improve the stability of enzyme due to the potency to form disulfide across two molecules. The results indicated that BP-1 (Ser236Cys) was found to gain 150% activity (Kcat/Km value) of the wild-type subtilisin E and 3-fold increase in stability in aqueous solution at pH7.4 and 50 degrees C, compared to the wild-type enzyme. However, further mutations on BP-1 to introduce Ala15Asp/Gly20His (BU-1) or Ser24His/Lys27Asp (BW-1) was found negative effects on the activity and stability of subtilisin E.
Yang
Y H
YH
Shanghai Research Center of Biotechnology.
Wu
Y J
YJ
Jiang
L
L
Zhu
L Q
LQ
Yang
S L
SL
D004795:Enzyme Stability; D016297:Mutagenesis, Site-Directed; D015202:Protein Engineering; D013329:Structure-Activity Relationship; D013381:Subtilisins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D013381:Subtilisins