Reengineering a â-lactamase using prototype

VALERIA A. RISSO; MARIA E. PRIMO; MARIO R. ERMACORA

PROTEIN SCIENCE

Cold Spring Harbor Laboratory Press

Lugar: Woodbury, NY ; Año: 2008

0961-8368

B. licheniformis exo-small â-lactamase (ESBL) has a complex architecture with twelve áexo-small â-lactamase (ESBL) has a complex architecture with twelve á helices and a five-stranded beta sheet. We replaced, separately or simultaneously, three of ESBL á helices with prototype amphiphatic helices from a catalog of secondary structure elements. Although the substitutes bear no sequence similarity to the originals and pertain to unrelated protein families, all the engineered ESBL variants were found able to fold in native like structures with in vitro and in vivo enzymic activity. The triple substituted variant resemble a primitive protein, with folding defects such as a strong tendency to oligomerization and very low stability; however it minis a non homologous recombinant abandoning the family sequence space while preserving fold. The results test protein folding and evolution theories. elements. Although the substitutes bear no sequence similarity to the originals and pertain to unrelated protein families, all the engineered ESBL variants were found able to fold in native like structures with in vitro and in vivo enzymic activity. The triple substituted variant resemble a primitive protein, with folding defects such as a strong tendency to oligomerization and very low stability; however it minis a non homologous recombinant abandoning the family sequence space while preserving fold. The results test protein folding and evolution theories. á helices with prototype amphiphatic helices from a catalog of secondary structure elements. Although the substitutes bear no sequence similarity to the originals and pertain to unrelated protein families, all the engineered ESBL variants were found able to fold in native like structures with in vitro and in vivo enzymic activity. The triple substituted variant resemble a primitive protein, with folding defects such as a strong tendency to oligomerization and very low stability; however it minis a non homologous recombinant abandoning the family sequence space while preserving fold. The results test protein folding and evolution theories.