TY - JOUR
T1 - The insertion of bioactive peptides at the C-terminal end of an 11S globulin changes the structural stability and improves the antihypertensive activity
AU - Espinosa-Hernández, Edgar
AU - Morales-Camacho, Jocksan Ismael
AU - Fernández-Velasco, D. Alejandro
AU - Benítez-Cardoza, Claudia G.
AU - Rosas-Cárdenas, Flor de Fátima
AU - Luna-Suárez, Silvia
N1 - Publisher Copyright:
© 2018
PY - 2019/1
Y1 - 2019/1
N2 - Background: The 11S globulin from amaranth is the most abundant storage protein in mature seeds and is well recognized for its nutritional value. We used this globulin to engineer a new protein by adding a four valine-tyrosine antihypertensive peptide at its C-terminal end to improve its functionality. The new protein was named AMR5 and expressed in the Escherichia coli BL21-CodonPlus(DE3)-RIL strain using a custom medium (F8PW) designed for this work. Results: The alternative medium allowed for the production of 652 mg/L expressed protein at the flask level, mostly in an insoluble form, and this protein was subjected to in vitro refolding. The spectrometric analysis suggests that the protein adopts a β/α structure with a small increment of α-helix conformation relative to the native amaranth 11S globulin. Thermal and urea denaturation experiments determined apparent Tm and C1/2 values of 50.4°C and 3.04 M, respectively, thus indicating that the antihypertensive peptide insertion destabilized the modified protein relative to the native one. AMR5 hydrolyzed by trypsin and chymotrypsin showed 14- and 1.3-fold stronger inhibitory activity against angiotensin I-converting enzyme (IC50 of 0.034 mg/mL) than the unmodified protein and the previously reported amaranth acidic subunit modified with antihypertensive peptides, respectively. Conclusion: The inserted peptide decreases the structural stability of amaranth 11S globulin and improves its antihypertensive activity. How to cite: Espinosa-Hernández E, Morales-Camacho JI, Fernández-Velasco DA, et al. The insertion of bioactive peptides at the C terminal end of an 11S globulin changes the structural stability and improves the antihypertensive activity. Electron J Biotechnol 2018;37. https://doi.org/10.1016/j.ejbt.2018.11.001.
AB - Background: The 11S globulin from amaranth is the most abundant storage protein in mature seeds and is well recognized for its nutritional value. We used this globulin to engineer a new protein by adding a four valine-tyrosine antihypertensive peptide at its C-terminal end to improve its functionality. The new protein was named AMR5 and expressed in the Escherichia coli BL21-CodonPlus(DE3)-RIL strain using a custom medium (F8PW) designed for this work. Results: The alternative medium allowed for the production of 652 mg/L expressed protein at the flask level, mostly in an insoluble form, and this protein was subjected to in vitro refolding. The spectrometric analysis suggests that the protein adopts a β/α structure with a small increment of α-helix conformation relative to the native amaranth 11S globulin. Thermal and urea denaturation experiments determined apparent Tm and C1/2 values of 50.4°C and 3.04 M, respectively, thus indicating that the antihypertensive peptide insertion destabilized the modified protein relative to the native one. AMR5 hydrolyzed by trypsin and chymotrypsin showed 14- and 1.3-fold stronger inhibitory activity against angiotensin I-converting enzyme (IC50 of 0.034 mg/mL) than the unmodified protein and the previously reported amaranth acidic subunit modified with antihypertensive peptides, respectively. Conclusion: The inserted peptide decreases the structural stability of amaranth 11S globulin and improves its antihypertensive activity. How to cite: Espinosa-Hernández E, Morales-Camacho JI, Fernández-Velasco DA, et al. The insertion of bioactive peptides at the C terminal end of an 11S globulin changes the structural stability and improves the antihypertensive activity. Electron J Biotechnol 2018;37. https://doi.org/10.1016/j.ejbt.2018.11.001.
KW - Amaranth
KW - Antihypertensive peptides
KW - Bioactive
KW - Culture media design
KW - Globulin
KW - Mature seeds
KW - Potato waste
KW - Protein engineering
KW - Protein expression
KW - Protein stability
KW - Storage protein
KW - Thermal stability
UR - http://www.scopus.com/inward/record.url?scp=85057836152&partnerID=8YFLogxK
U2 - 10.1016/j.ejbt.2018.11.001
DO - 10.1016/j.ejbt.2018.11.001
M3 - Artículo
AN - SCOPUS:85057836152
SN - 0717-3458
VL - 37
SP - 18
EP - 24
JO - Electronic Journal of Biotechnology
JF - Electronic Journal of Biotechnology
ER -