Tolerance of Escherichia coli beta-galactosidase C-terminus to different-sized fusions.
The tolerance of the beta-galactosidase C-terminus to foreign protein fusions has been explored by using different-sized derivatives of the chimeric protein LACVP1. While the molecular mass of the partner domain shows a minor influence on protein toxicity for the producing E. coli cells, it dramatically affects the proteolytic susceptibility of the whole fusion. Surprisingly, the observed structural modulation of proteolysis is not an all-or-nothing process, but it exhibits a continuous effect concomitantly with the length of the fusion. The conformational effects caused by increasingly sized partners seem to progressively expose cryptic protease target sites, initiating a proteolytic cascade that dramatically reduces the yield of the recombinant protein.
Institut de Biologia Fonamental and Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.
J L
JL
Corchero
A
A
Villaverde
D000595:Amino Acid Sequence; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D010957:Plasmids; D011993:Recombinant Fusion Proteins / Q000235:genetics* / Q000378:metabolism* / Q000633:toxicity; D012995:Solubility; D013329:Structure-Activity Relationship; D001616:beta-Galactosidase / Q000235:genetics* / Q000378:metabolism*
D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D001616:beta-Galactosidase