title: Effect of adding amino acids residues in N- and C-terminus of Vip3Aa16 (L121I) toxin.
abstract: To study the importance of N- and C-terminus of Bacillus thuringiensis Vip3Aa16 (L121I) toxin (88 kDa), a number of mutants were generated. The addition of two (2R: RS) or eleven (11R: RSRPGHHHHHH) amino acid residues at the Vip3Aa16 (L121I) C-terminus allowed to an unappropriated folding illustrated by the abundant presence of the 62 kDa proteolytic form. The produced Vip3Aa16 (L121I) full length form was less detected when increasing the number of amino acids residues in the C-terminus. Bioassays demonstrated that the growth of the lepidopteran Ephestia kuehniella was slightly affected by Vip3Aa16 (L121I)-2R and not affected by Vip3Aa16 (L121I)-11R. Additionally, the fusion at the Vip3Aa16 (L121I) N-terminus of 39 amino acids harboring the E. coli OmpA leader peptide and the His-tag sequence allowed to the increase of protease sensitivity of Vip3Aa16 (L121I) full length form, as only the 62 kDa proteolysis form was detected. Remarkably, this fused protein produced in Escherichia coli (E. coli) was biologically inactive toward Ephestia kuehniella larvae. Thus, the N-terminus of the protein is required to the accomplishment of the insecticidal activity of Vip3 proteins. This report serves as guideline for the study of Vip3Aa16 (L121I) protein stability and activity.
authors.affiliation: Biopesticides Team LPAP, Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Sameh
authors.initials: S
authors.lastname: Sellami
authors.affiliation: Biopesticides Team LPAP, Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Marwa
authors.initials: M
authors.lastname: Cherif
authors.affiliation: Biopesticides Team LPAP, Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Kaïs
authors.initials: K
authors.lastname: Jamoussi
mesh_terms: D000596:Amino Acids / Q000235:genetics; D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics / Q000472:pathogenicity*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics* / Q000633:toxicity*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D007306:Insecticides / Q000633:toxicity*; D007814:Larva / Q000254:growth & development*; D009036:Moths / Q000187:drug effects / Q000196:embryology / Q000254:growth & development*; D010572:Pest Control, Biological
chemical_list: D000596:Amino Acids; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D007306:Insecticides; C447139:Vip3A protein, Bacillus thuringiensis; C078167:OMPA outer membrane proteins
keywords: Bacillus thuringiensis; Ephestia kuehniella; Protease sensivity; Vip3Aa16 (L121I)