SolutionSet5-2 - BMB100B Winter 2010 Rubin Solution Set#5 1...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
BMB100B Winter 2010 Rubin Solution Set #5 1) Another type of protease that carries out the same peptide hydrolysis reaction as serine proteases is the Zn protease. Below is a schematic of the active site containing the Zn and a Glu. Propose a mechanism for the Zn protease catalyzed hydrolysis reaction. Use the picture and add a water to depict the beginning (ES complex) state and draw the tetrahedral intermediate and product states. Be sure to indicate movement of electrons with arrows and all formal charges. Here are two answers: This first mechanism is simple and applies the key concepts that are important for you to know from lecture: Here the Glu acts as a base (take H 2 O proton) and acid (donate to leaving H 2 N-R’). The role of Zn is to activate water, i.e. make the H 2 O proton more acidic so that even the weak glutamate base can deprotonate it. The second answer is a more complicated (but more accurate according to the actual experiments done to determine the mechanism):
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
BMB100B Winter 2010 Rubin This more detailed mechanism is somewhat similar to the simple first mechanism, but the Zn also stabilizes the negative charge that builds on the carbonyl O in the tetrahedral intermediate. Note that it has been determined that the tetrahedral intermediate O actually coordinates to the metal (metal-ligand bond) but this inorganic chemistry detail is beyond the scope of this course. If your answer looked like the first mechanism, you understand the catalysis concepts well! b) The serine protease mechanism (e.g. chymotrypsin, etc.) is often characterized as covalent catalysis. Would you characterize the zinc protease mechanism as covalent catalysis? What is the key difference between this mechanism and the serine protease mechanism?
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern