Genotypic Expression Behind the Tall and Dwarf Peaks in Peptide Fragmentation
Format
Poster Presentation
Faculty Mentor Name
Jianhua Ren
Faculty Mentor Department
Chemistry
Graduate Student Mentor Name
Yadwinder Singh Mann
Graduate Student Mentor Department
Chemistry
Abstract/Artist Statement
Introduction:
Why is it that in peptide fragmentation there are intense peaks and others that are small? The present experiment has allowed us to investigate the reason behind this question. Although the peptides fragment at various positions along the backbone, ions produced from the fragmentation of the amide backbone are highly abundant compared to other ions. The C terminal ions and the N terminal ions are referred to as b and y ions respectively. Peptides mostly produce high intensity of b2 ions while the peptide analogues, peptoids, have higher intensity of Y ions. In peptoids, the basicity of the Y ions could be the possible reason behind this phenomenon. The position of the side chain in the peptoid leads to the higher basicity of C terminal ions as the amine is secondary.
In order to test out the hypothesis that basicity increases the abundance of ions or not in peptides, solid phase peptide synthesis (SPPS) was used to synthesize proline containing peptides as the genetic makeup is similar to peptoids. The C-terminal ions in proline containing peptides are similar to peptoids, as they have a higher basicity compared to other peptides.
Method:
The peptide PPPP (P4), GGGG (G4), and GGPG were synthesized using solid phase peptide synthesis (SPPS) procedure. Liquid nitrogen was used to solidify the solution, which was then placed in a lyophilizer to purify the peptides. The Varian 320 mass spectrometer instrument was used to confirm the identity and analyze the fragmentation pattern.
Result:
This research has shown that there is a higher abundance of y-ions in P4 when comparing it to G4. Which is explained by the similarity of proline peptides to peptoids and increased basicity. Thus, concluding that the basicity of the peptide synthesized will change the fragmentation pattern in relation to the peak intensity of b-ions and y-ions.
Location
Virtual
Start Date
25-4-2020 1:00 PM
End Date
25-4-2020 3:00 PM
Genotypic Expression Behind the Tall and Dwarf Peaks in Peptide Fragmentation
Virtual
Introduction:
Why is it that in peptide fragmentation there are intense peaks and others that are small? The present experiment has allowed us to investigate the reason behind this question. Although the peptides fragment at various positions along the backbone, ions produced from the fragmentation of the amide backbone are highly abundant compared to other ions. The C terminal ions and the N terminal ions are referred to as b and y ions respectively. Peptides mostly produce high intensity of b2 ions while the peptide analogues, peptoids, have higher intensity of Y ions. In peptoids, the basicity of the Y ions could be the possible reason behind this phenomenon. The position of the side chain in the peptoid leads to the higher basicity of C terminal ions as the amine is secondary.
In order to test out the hypothesis that basicity increases the abundance of ions or not in peptides, solid phase peptide synthesis (SPPS) was used to synthesize proline containing peptides as the genetic makeup is similar to peptoids. The C-terminal ions in proline containing peptides are similar to peptoids, as they have a higher basicity compared to other peptides.
Method:
The peptide PPPP (P4), GGGG (G4), and GGPG were synthesized using solid phase peptide synthesis (SPPS) procedure. Liquid nitrogen was used to solidify the solution, which was then placed in a lyophilizer to purify the peptides. The Varian 320 mass spectrometer instrument was used to confirm the identity and analyze the fragmentation pattern.
Result:
This research has shown that there is a higher abundance of y-ions in P4 when comparing it to G4. Which is explained by the similarity of proline peptides to peptoids and increased basicity. Thus, concluding that the basicity of the peptide synthesized will change the fragmentation pattern in relation to the peak intensity of b-ions and y-ions.