Proteometics

Question 1

1. What does proteomics research invesitigate and study, what makes it different than genomic study?

Answer 1

• Systems that encompass proteins such as cell, organism, tissue and analyses them at a large scale.
• It can examine their structure; what it’s made up of and all of it’s characteristics and function, post translational modifications, interaction between any molecules, RNA editing and can compare all of the proteins in a system with each other. Can compare it over time, under different conditions.
• It’s complex because it’s a dynamic system(can change at genome, RNA or protein level) with many different levels of changes(cleavage, phosphorylation) and interaction with many different molecules and systems (proteins& nucleic acids), difficult to study function and structure in a specific context. While genome is relatively stable and highly conserved and the changes that do occur don’t at a wide range.

Question 2

2. What are the ways proteometics is studied?

Answer 2

• Classical protein biochemistry
• SDS PAGE, gel electrophoresis
• Immuno-affinity techniques
• Amino acid sequencing
• Mass spectroscopy

Question 3

3. What is MALDI?

Answer 3

Uses matrix and UV light to ionize the peptides and then the peptides are examined for their mass to charge ratio in time of flight spectroscopy.

Question 4

3. What is Qtof MS-MS?

Answer 4

• It sequences 1 peptide to identify it, by trapping it in a quadruple filter and colliding it with an inert gas and then it fragments and you analyse it using TOF, you take the masses of the amino acids and calculate the sequence.

Question 5

5. What is Q-TOF?

Answer 5

It’s a mass spectroscopy technique that quantifies the abundance of cerain peptides based on their time of flight, which is based of their mass to charge ratio.

Question 6

6. How to be quantitative?

Answer 6

• Before using mass spectroscopy you add isobaric tags or stable isotopes to the cell culture of the protein of interest to quantify the abundance

Question 7

7. What is the importance of bioinformatics analysis?

Answer 7

• It gives you the information needed to sequence the peptide or the protein, can find the coding sequence match, not only the sequence but everything you need to know about this sequence is in database, what’s associated with disease, molecules it interacts with, mutations, it helps characterize the peptide you’re studying.

Question 8

8. How is proteometics applied?

Answer 8

• It’s used for seeing protein interactions, rapid diagnosis, modelling biological processes, response to drugs, personalized medicine, biomarkers, understanding complex diseases.