Daily Silver: Here I am writing about peptidoglycan for my roommate.

So, every time I ask my roommates what I should write a blog post on, my one roommate L says "peptidoglycan."  Since it was her birthday this week, I'm going to write about peptidoglycan (not too much I promise, as she is the only person I've ever met that thinks it's interesting).

I know there are some of you who are staring at the computer screen right now, eyes slowly glazing over, saying to yourself "what the heck is peptidoglycan?"  Peptidoglycan is a carbohydrate-protein scaffolding (called a polymer) that is a major component of some bacterial cell walls.  All living things are made up of cells, and animal cells are different from plant cells are different from bacterial cells, and so on.  One [of the many] major differences between animal cells and bacterial cells is that bacteria have what is called a cell wall, which is pretty much exactly what it sounds like: it's a stiff boundary that surrounds the cell and helps it keep its shape.  That's why we animals are so squishy, our cells don't have walls, they only have membranes which are fluid (bacteria also have cell membranes, in addition to the wall).

Peptidoglycan isn't very exciting on the whole, except for one thing: penicillin.  You may know parts of this already, but a quick refresher: penicillin is an antibiotic, meaning it kills bacteria.  Actually, it's kind of THE antibiotic, because it was the first substance used therapeutically (medically, to treat disease) as an antibiotic, and the story is a study in serendipity.  In 1928, Scottish scientist Alexander Fleming was culturing some bacteria.  When you culture bacteria, you coat the bottom of Petri dish with a medium like agar (something with sugars and other nutrients in it that growing bacteria need) and then you spread bacteria from somewhere--another culture, some lake water, your mouth--over the medium with a Qtip or a plastic rod or something.  Then you stick it in an incubator (many bacteria require temperatures similar to body temperature to grow) and wait a while.  But when Fleming came back and took his plates out of the incubator, he noticed far less bacteria growing than he'd expected.  He also noticed that there were spots of fungus growing on the plates, and there was a circle around the fungus where no bacteria were growing.  Voila; penicillin!  The fungus was Penicillium notatum, and he found that when it was grown under the right conditions it secreted a substance that acts as an antibiotic; he called it penicillin.

Nowadays, the term is used to describe a group of naturally derived antibiotics, so when the doctor asks if you're allergic to penicillin she's actually asking if you are allergic to the fungus P. notatum and/or substances derived from it.  What does this have to do with peptidoglycan? you ask (and if you weren't asking it just pretend you were).  Glad you asked.

Penicillin is antibiotic because it inhibits the formation of the peptidoglycan wall.  It stops links from forming between individual peptidoglycan subunits and results in an overall weakening of the wall and even holes in places.  Because bacteria are constantly remodeling and repairing their cell walls, penicillin acts pretty quickly, stopping the individual parts from linking up.

Remember how I said that the wall helps the cell retain its shape?  Cells are basically bags of fluid and protein and sugars, and they're surrounded by more fluid and protein and sugar.  At all times, the weights of the water inside and outside the cell are fighting.  Think of when you swim all the way to the bottom of the pool and you can feel the water squeezing you harder the deeper you go.  It's a complicated and dynamic process, keeping enough water pressure inside the cell to keep it from collapsing, and at the same time having little enough pressure that the cell doesn't burst, and the cell wall makes it a little bit easier, itself pushing both in and out.  But when the wall is weak, the cell is not equipped to handle all those conflicting pressures by itself, so it bursts.  Peptidoglycan has, however indirectly, killed the cell.

So that's the main reason for focusing on peptidoglycan.  We're always looking for faster, better, easier ways to rid people of disease.  Not all bacteria contain peptidoglycan cell walls, but knowing about the penicillin mechanism offers new ways to go about looking at other potential systems for killing bacteria in our water, our waste, and in our bodies.

There's peptidoglycan in a nutshell.  Happy birthday, L!

Playing god and other human pursuits.

Today I'm thinking about euthanasia.  Alternately, murder.  I don't know.

Up until a few years ago I was set on a career in veterinary medicine.  I wanted, needed to be a veterinarian.  I... honestly, I don't really know why it was so important to me.  At first I suppose it was just like, "Oh I love animals, and I want to work in the sciences, and I want to help the animals that live with us."  I have always liked animals more than humans to some extent; as I've aged it's shifted from disgust with the human race and reverence of non-human animals to, well, I'm still pretty disgusted with humans, but it's less of a generalization and more on a case-by-case basis.  So when I was little I deemed non-human animals more deserving of medical care.  I counter any protests of "But you're human, and our pets need humans to provide that care," with "I was, like, six years old."  Six-year-olds aren't known for their expansive considerations of reality (ie how the world works).

As I got older I developed more concrete reasons for becoming a vet.  I started feeling that pulling at my heart when I thought of animals suffering illness or mistreatment.  I realized that I felt personally obligated to do whatever I could to help them, for they could not help themselves.  I still feel that obligation, but I realize now that your life's work should also be something that is fascinating to me, and my fascination is not in veterinary medicine.

My career plans are not the point.  So what is? you ask.  The point: one disparity between medicine for humans and non-humans is at the end of medicine.  By that I mean, of course, how and when death comes.

The very simple fact is: humans often choose when an animal will die.  Another simple fact: it is illegal and usually considered amoral for humans to choose when a human will die (with exceptions and/or loopholes).  Why?  If you ask someone that question, chances are they will have a hard time with a solid answer.  I've thought about this question a lot, and I've come to the conclusion that the law is as it is because there is an inherent assumption that humans are more important than non-humans.   I wouldn't expect an easy answer out of anyone to this question, either, even though it's basically a yes/no question.

My take is that it's something that people believe deeply--perhaps subconsciously--but are uncomfortable voicing aloud.  But shouldn't a person be able to say what she thinks?  Also, this belief in human superiority is probably widely-held, so speaking it aloud would place one squarely within the clear--albeit close-mouthed--majority.

I will speak: I do not agree with the statement that humans are more important than non-humans.  I strongly believe that humans are of equal importance with non-humans.  Who knows, maybe I'll change my mind in a few years; I did start out believing that non-humans were of more importance than humans.

The most trouble I have with that statement is the use of "important."  Calling something important implies that there is a purpose for it, and we've already said there is no purpose for living things, nor even for living.  Actually, Oxford English Dictionary defines important as "of great significance or value; likely to have a profound effect on success, survival, or well-being."  You could argue that because of the inclusion of "profound effect on... survival" it might have bearing on the relationship between these two things (humans and non-humans); actually there is no relevance to this comparison because the it is not comparing to methods of finding food or shelter or anything like that, so there is no element of survival.  It is not calling into question the survival skills of either being, but comparing them as if they were instrumental to some sort of universal scheme, which smacks of monotheism (and actually most religions with divinity/-ies). 

So the natural next question is "Why then do we decide when animals die and not when humans die?"  When we can't easily answer that one, we might go to "Why is it socially acceptable to decide for animals and not humans?" or even "Is it right?"  And then we get to right vs wrong, my least favorite dichotomy of all time (and I can even say with confidence that I will never meet another dichotomy that I loathe more).

It's been a hard week.

More thoughts on morality, along the lines of "Why?"

The Quest of Dr. Paul Farmer : NPR

I felt as though, in Farmer, I'd been offered another way of thinking about a place like Haiti. But his way would be hard to share, because it implied such an extreme definition of a term like "doing one's best."

This is an excerpt from a piece on the NPR site (which is actually an excerpt from Mountains Beyond Mountains) about Paul Farmer, the guy I was talking about in my last post.

In a way it articulates what I have been trying to say: "charity" as such is beyond the scope of what [I would suggest] most of us concieve of as charity.  Charity is self-sacrifice but not in the sense that there is sacrifice.  I look at Farmer because he is an example near-at-hand, and I see that he sacrificed time and money to help the poor of Haiti.  More significantly, perhaps, is that he sacrificed that staple of American life: comfort.  In the excerpt from Mountains, Kidder tells of how he met Farmer and came to learn about his life.  He writes:

He worked in Boston four months of the year, living in a church rectory in a slum. The rest of the year he worked without pay in Haiti, mainly doctoring peasants who had lost their land to a hydroelectric dam.

Yet Kidder noted as they had dinner in Miami:

He clearly liked the fancy restaurant, the heavy cloth napkins, the good bottle of wine. What struck me that evening was how happy he seemed with his life.

While we can't get into Farmer's mind, it seems to me that he would have to view his work in Haiti as anything but a sacrifice in order to keep up this hectic lifestyle.

But is charity such ignorant sacrifice?  ("Sacrifice" here meaning something that takes from the one who gives it.)  And is sacrifice charity?  I guess the question is not if we should redefine something but what we should redefine?  I think we've pretty clearly got the meaning of "sacrifice" down here, but I think we've got a bit more difficulty in "charity."

The Evolution of a Sort of Moral Code; A Belief in Ethics, If You Will.

Ethics and morality are slippery and always-controversial subjects.  I often avoid them for that very reason, but I find that I cannot always stand quietly by in the shadows.  I need for my voice to be heard.

I'm reading Pathologies of Power by Paul Farmer, a fairly well-known medical anthropologist.  You may have heard of Tracy Kidder's book Mountains Beyond Mountains, which is about Farmer's quest for global health.  I don't mean the sort of global health that is tracking who gets sick and where so disease can be controlled and contained, I mean global health in the sense that the whole world, everyone in the world has access to such resources that might keep or make them healthy.

I just have a quick note (because I've only just started the book) about my thoughts on charity and morality, actually.

"The ends justify the means."  When Machiavelli wrote that, he was thinking and writing of governments and rulers, not the rights and freedoms of the ruled; in fact, I've heard it argued that he was thinking the opposite, and many commonly define his "ends" as a total subjugation of the people.  I believe that, whatever the original ideas behind the statement, it can be applied to my concept of charity and morality.  The end in this case is the improvement of living conditions and quality of life for a people, and the means are all the charities that funnel money and labor into this project, and all the donations by the well-off to those charities.

The first part (of two) of Farmer's book is titled "Bearing Witness;" the first part of the first part--a sort of prologue to the part--is an elaboration on that title.  Farmer says he is anxious about the title and a reason he gives is that he is apprehensive of misrepresenting the poor.

"Some of my anxiety has legitimate sources: the boundary between bearing witness and disrespectful (or self-interested) rooting is not always evident, even to those seeking to be discerning." 

This is his way of saying "morality" for its own sake is not morality.  I use "morality" here to represent many of the good-samaritan acts or charity projects that the well-off do for the worse-off.

I want to emphasize that I don't think that charity and such is "bad," I just think it's maybe not as truthful as we'd like it to be.

I'm having trouble forming coherent sentences, so I think I'm going to go to sleep now.  But as I read the book, I'm sure I'll have a lot more to say.  Thanks for listening!