"Finding my Kd"

I stand there, poised and ready. Suddenly, a ball whirrs past my face. “Ha!” I think. “Missed me!” Suddenly, as though I’m in the receiving end of a batting cage, balls start going and going and going. I do the “try-not-to-get-hit dance” ---one that is ultimately doomed to failure, not necessarily because my dancing skills are all that bad, but because there are so many coming so fast from all different directions. Suddenly, the balls start to…stick. Some stick better than others, latching onto me as if they’ll never let go a la crying-toddler-with-death-grip. Others stick weakly, falling to the ground after the slightest movement. I feel like I’ve become a human velco-coverd target, akin to that game you play with a soft ball and the Velcro paddles (wow, am I ever dating myself here—my set was neon green and screaming pink brand new, but then after copious amounts of oops-I-left-it-outside it matched the dress on Totally Hair Barbie. Thanks, 90s. You’re pretty rad).

Totally Hair Barbie. God, that pouffant.

Anyways, there I am, in the midst of this mess, when I start thinking, “Man, something is going on.”

Something is going on. And although I don’t go around trying to sound like a tagline from a commercial from a made-for-TV movie on the Oxygen Network, what is going on is life.

Things are thrown at you every day of every week of every year. Some stick around (family health issues, for example). But others fall off in the time it takes to process and forget about it (oh, I screwed up the concentrations in the buffer I'm making..I'll have to redo it!). And there is enormous spectrum covering everything in between.

Sometimes I feel completely drowning in these problems…so much hits me in so little time that all I want to do is lay down in the fetal position, so at least they don’t hit me so hard. I feel like there’s no other option, but then I realize well, duh…even if I can’t change the magnitude or velocity of these challenges, I can influence my response to them. This starts by changing my own behaviors, the trifecta of sleep, exercise, and eating. It puts me in the best place to defend against the 90 mph fastballs ready to implant themselves in my left shoulder. But there’s also another way. And it’s as simple as asking for help. I can enlist friends to come and help me out in my batting cage; hit these problems away before they even reach me, or knock them off me entirely. I'll get back to this concept later.

But, at the core of it, my problem has to do with affinity…in this case, how well these balls stick to me. In science, this affinity is described by a constant called the “Kd” or the disassociation constant (when you say it in conversation, you actually just say the letters “K” and “D”). In effect, instead of describing how long it stays, it describes how soon it leaves. But, these are used to describe the general biochemical “stickiness” of molecules for one another. This stickiness this is based on phyisco-chemical properties of those molecules.

[Physico-chemical encompasses all of the physical and chemical things that define a given molecule; how electrons interact, the shape of the molecule, the interactions inside the molecule, all that. It also includes the sequence of amino acids in a protein to the actually topology…as in, what it looks like in 3D. In person-speak, we'd be describing this person's personality and physical attributes; tall, blonde hair, sarcastic, etc].

One of the goals in biology is to gain a better understanding of how two molecules interact, which is done by measuring the affinity the two molecules have for each other. In the same way, two very strong magnets have very high affinity to each other (thinks neodymium magnets), and two weak magnets have affinity to each other but a kind that unsticks easier (think cheap refrigerator magnets).

[As a quick primer, we all know protein as the stuff that’s in meats, legumes, all that. But when I describe protein in a biological sense, I’m not thinking about a lean chicken breast pureed in a test tube…I’m talking about a chain of amino acids folded in a particular way to function in a particular way; in building up our fingernails, in making our muscles, in digesting food, in detecting foreign particles in our blood. These chains of amino acids are different for every protein, and they’re determined by the genes in our DNA. Your DNA is most similar to that of your parents, or your twin or siblings if you have siblings; which is why you have the greatest chance of looking like them; DNA encodes all those different proteins that help us grow, give our hair shape and pigment, etc.]

Anyways, it is possible but not necessarily easy to measure the affinity between two molecules to produce what is known as a binding curve....when there are, say 30 molecule 1's and 100 molecule 2's, what number of those are together in a pair? I'm not going to turn this post into lots about crazy maths and graphs and such (you know how me and the Maths get along) - but this concept of stickiness in biology impacts a lot of your everyday life: development of new drugs to treat diseases like cancer, your ability to taste different foods, digestion of food, transmission of hormones throughout your body...all sorts of stuff! As my favorite chemist would say, "It's really all just chemistry!" And it really is.

Which brings me back to my life. If you bring the world back into this concept and say, "Okay. Let's pretend Bridget is Molecule 1, and a problem registering for classes is Molecule 2. What happens?"

Well, if it's me, I'd say, eh, something to deal with, but not something that stays around for awhile; it's an interaction that happens and falls off rather quickly....an interaction of low affinity. But what if Molecule 2 is something like, say, a problem in designing an experiment in lab? Well, if this keeps giving me trouble, it's something that I'll need help with...and that's where friends come in!

In molecular terms, these friends can be enzymes, other proteins, all sorts of things. But they are all working in this situation to help remove the offending Molecule 2. In the case of my labwork, it would be someone helping me solve a problem. In the case of molecules, it could be that another molecule comes by that actually sticks to molecule 2 even BETTER than I do...so it switches to that other molecule!

The point is, in the very microscopic world of biology in your cells to the very macroscopic world of your life, affinity rules interactions with the environment. The help a TA can give you governs how you spend your time to meet with them. The fun you can have with a friend because they make you feel calm and happy---well, that gives you that incentive to be near them, drawn to them, almost as north and south poles of magnets are drawn to each other. Yes, you can most definitely have affinity for people in your life. They're the ones who defend you from the onslaught of neon pink and green sticky balls, trying to shield your face and protect you.

And that's why I named this blog "Finding my Kd." I'm trying to find the things in my life that stick; a job that I absolutely love beyond measure, a group of people that I feel completely at home drinking champagne and eating nutella with a spoon, recipes that make me feel healthy and happy, interesting hobbies that keep me excited to learn---all that. I'm trying to find my affinity. For life. And that is a process that takes time, care, and dodging a whole lot of velcro balls.