M201PS2Answers2008

M201PS2Answers2008 - MICB 201 Chapter#2 Answers Problem#1...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
MICB 201 Chapter #2 Answers Problem #1 Experiment #1 (comparing the effect of lysozyme on Gram +ve and Gram -ve bacteria): Lysozyme kills cells by disrupting preexisting peptidoglycan. In order to have an effect, it must gain access to peptidoglycan which lies outside the cytoplasmic membrane. The PG of Gram +ve bacteria is exposed to the environment while the PG of Gram -ve bacteria is protected by the OM. Thus the Gram +ve bacteria more susceptible to lysozyme than Gram -ve bacteria. Experiment #2 (comparing the effect of lysozyme on a Gram -ve bacterium +/- EDTA): The Gram -ve bacterium can be made susceptible to lysozyme by combining it with EDTA. Why? As the problem states, EDTA binds Ca +2 and Mg +2 ions. Such ions are present in the outer membrane of Gram -ve bacteria where they prevent electrostatic repulsion between LPS molecules which would destabilize the membrane. It is expected that removal of these ions by EDTA would disrupt the outer membrane allowing lysozyme to penetrate to the PG in the periplasm.
Image of page 1

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

View Full Document Right Arrow Icon
Image of page 2
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