Scientists ahead of their time

Posted on April 10, 2011 by Michael

“[I]f we could intervene in the antagonism observed between some bacteria, it would offer perhaps the greatest hopes for therapeutics.”

~Louis Pasteur

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How penicillin works

Posted on March 18, 2011 by Michael

I’m currently in the midst of a short break I’m taking whilst studying for a massive microbio test I have in a few hours. And what better way to take a break than to post about one of the essay questions I know will be on the exam?

β-lactam antibiotics include penicillin and cephalosporins. (Everything that follows applies to both, but most people seem to be more interested if the topic is the more familiar penicillin subgroup.) The way these antibiotic works is by attacking the cell walls of bacteria. This makes gram-positive bacteria more susceptible than gram-negative bacteria; gram-positive bacteria have an outer peptidoglycan layer whereas gram-negative bacteria have their peptidoglycan layer between a plasma-membrane layer and an LPS layer. (No, I’m not going to define all these terms I’m using.)

Transpeptidase molecules are necessary for catalyzing cross-linking of glycan-linked peptide chains. Penicillin, all coy and sneaky, causes transpeptidase to link to it (penicillin) instead. (Transpeptidases are known as penicillin-binding proteins, or PBPs. I find the name misleading since it sounds like their purpose is to get all buddy-buddy with penicillin.) This prevents cross-linking. As I’m sure every nerd knows, cross-linking is what gives the peptidoglycan outer wall much of its strength. So while cell wall synthesis continues unabated, no cross-linking is happening, thus weakening structural integrity. Mike Holmes would be pissed if he was a biologist and he saw this happening. (Come on, HGTV fans, I know you’re out there.) Furthermore, autolysins are being released. What this means is the gram-positive bacteria has a weak and self-degrading outer wall. Osmotic pressure eventually causes lysis.

Now please excuse me while I enter hour 6 of studying for the (literally) 109 other things I need to know for my upcoming test.

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Local paper advertises for Maloney

Posted on July 15, 2010 by Michael

Christopher Maloney has written another letter to the editor of the local paper. Unlike his first letter, this one isn’t filled with so many lies.

Thank you for the July 10 editorial about antibiotic use in livestock.

The most troubling aspect of constant use of antibiotics in livestock is that human patients are often asked to forgo similar “preventative” antibiotic use so we won’t contribute to bacterial resistance to antibiotics.

A sick child with a likely viral infection will not get antibiotics, while millions of livestock animals in close quarters receive a daily dose. It is as if we have placed our food above our children in importance.

Small local farmers are providing world-class alternatives to the overuse of antibiotics. Purchasing locally rewards those who use antibiotics appropriately while growing our community. Those looking can check with the farmer’s markets, http://www.maloney medical.com or the Maine Organic Farmers and Gardeners Association.

Christopher Maloney, N.D.

Augusta

Okay, so he is lying when he tries to imply he’s somehow a legitimate doctor with his naturopathic title, “N.D.”, but other than that…he’s actually reasonable. UPDATE: That’ll teach me for not reading such quackery more closely (and at 1:30 in the morning). Antibiotics have nothing to do with treating viruses. They are for bacteria. I expected too much from Maloney.

Of course, there is still the issue of the paper allowing Maloney to put his bogus website in his letter. They’re putting the health of Maine residents at risk by allowing him to link back to his quackery without any sort of disclaimer – especially given the fact that he’s actually making a real point and now spewing some naturopathic, anti-science bullshit.

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