Cloning and Expression of Bovine Alpha S1 Casein Peptides of Variable Size and Position of spPEP Inhibitor Sequence

<p><em>Eurygaster integriceps </em>Puton<em> </em>(Sunn pest) is the most damaging insect pest of wheat in areas of North Africa, Eastern Europe and Western and Central Asia. Sunn pest injects an enzyme characterized as a prolyl endylprotease (spPEP) into wheat grains that digests the gluten protein (Darkoh et al., 2010). Previous studies have shown that casein peptides generated by <em>Lactobacillus </em>species<em> </em>have inhibitory effects on human (hPEP) and bacterial prolyl endoproteases (bPEP) which makes casein a good natural candidate to inhibit spPEP. Developing biopesticides for food products from αS1 casein is complicated due to some allergenic amino acid sequences. Ruiter et al (2005) identified a non-allergenic peptide region on αS1 casein that includes a previously identified inhibitory sequence (LNENLLRFFVAPFPEVFG) to hPEP (Jeanneret, 2011). The Objective of this study was to produce 16 recombinant peptides derived from αS1casein of varying lengths and varying placement of the non-allergenic inhibitory sequence. The inhibitory region is positioned at 0, 10, 20 and 30 amino acids from either N’ terminal or C-terminal end. Each of the peptides were cloned into pET15b for expression with a His tag for purification and thrombin site for removal of His-tag Peptides were incubated with either hPEP or spPEP in the presence of the substrate GPpNA. We report the inhibition of both enzymes based on size and placement of the inhibitory sequence.</p>

Name thesis:degree_name

Master of Science - Biotechnology

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Biology

Year dc:date.available

2016

Author dc:creator

• Vishram, Avleen Kaur

Contributors dc:contributor

• Dr. Beatrice Clack
• Dr. Rebecca Parr
• Dr. Odutayo Odunuga

Repository record dc:identifier

https://scholarworks.sfasu.edu/etds/64

OAI identifier oai:identifier

oai:scholarworks.sfasu.edu:etds-1067