6 thoughts on “D108 – Choi

  1. Question Asked: You mentioned that you were trying to determine whether your compound was bactericidal or bacteriostatic, what is the difference between these two in terms of their effectiveness?

    1. Bactericidal and bacteriostatic differ in that bactericidal antimicrobials actually kill the bacteria cell, whereas bacteriostatic simply prevent further bacteria replication and growth. Although it sounds like bactericidal are more effective, bacteriostatic antimicrobials are still super effective as antibiotics because they can prevent bacterial growth long enough for your immune system to fight back.

  2. You mentioned that Polynexin B could penetrate ground negative and positive cell membranes, and I was wondering if you could explain what those are.

    1. For sure! Gram positive bacteria have a thick peptidoglycan (comprised of sugar polymer) walls that surround their membrane outer layer. Gram negative bacteria have a thinner peptidoglycan wall, but also a lipopolysaccharide outer layer that protect their cell membranes. Gram negative bacteria are typically more dangerous because their lipopolysaccharide layer protects them from some antimicrobials, and the fact Polymyxin B can penetrate both makes it a good candidate as an antibiotic.

    1. Good question. When beginning our research one of our group mates mentioned research he learned about it in his biochemistry class. Although we wanted to initially use a compound called Magainin, initial tests with it returned no promising results. So we moved forward with the next best compound, Polymyxin B, which did return promising results.

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