User:Steven J. Koch/Notebook/Kochlab/2009/07/17/DTRA Abstracts/Andy

Version 1

Both the molecular motor kinesin and its substrate microtubules have been proposed as components of chemical and biological sensors for microdevices and other MEMS applications.

In order to retain the motor activity of kinesin, it has been shown that the surfaces with which kinesin interacts must must be passivated [with organic molecules?]. The most popular surface blocker is the casein family of milk proteins, composed of three major components that exhibit amphiphilic behaviors. Casein is usually purified to various degrees from bovine milk and has many unknowns associated with it when reconstituted and used in motor protein assays.

In order to obtain a clearer picture of how kinesin and microtubules interact, a cleaner surface passivation needs to be found.

The interaction of kinesin with microtubules has been studied extensively, however, there are fewer studies that investigate how the interaction of kinesin and microtubules changes due to surface passivation. One recent study has shown that the differing components of casein (termed alpha, beta, kappa) can significantly affect microtubules in gliding motility assays. [Cite Hancock paper and put in reference at end of abstract.]

Gliding motility assays are assays where a glass cover slip is passivated and kinesin is allowed to embed itself in the passivated surface. [I don't like the term "embed" unless you've definitely seen experimental proof that it's embedded, as opposed to mysteriously attached.] Microtubules are then propelled by the motor activity of a bed of immobilized kinesin molecules.

Lipid molecules are fatty acids that can be purified to a much greater extent than casein can. Also, lipid molecules exhibit the same amphiphilc behavior as casein, are easily applied to glass surfaces, can be easily functionalized. Lipids are thus an attractive alternative to casein proteins for surface passivation. We report preliminary results on the surface passivation performance of lipid molecules in gliding motility assays.

[Hancock reference]

Version 2 Now with a title

Surface passivation for molecular motor protein assays

Both the molecular motor kinesin and its substrate microtubules have been proposed as components of chemical and biological sensors for microdevices and other MEMS applications. In order to retain the motor activity of kinesin, it has been shown that the surfaces with which kinesin interacts must must be passivated in order to prevent kinesin from denaturing on them. The most popular surface blocker is the casein family of milk proteins, composed of three major components that exhibit amphiphilic behaviors. Casein is usually purified to various degrees from bovine milk and has many unknowns associated with it when reconstituted and used in motor protein assays. In order to obtain a clearer picture of how kinesin and microtubules interact, a cleaner surface passivation needs to be found. The interaction of kinesin with microtubules has been studied extensively, however, there are fewer studies that investigate how the interaction of kinesin and microtubules changes due to surface passivation. One recent study has shown that the differing components of casein (termed alpha, beta, and kappa) can significantly affect microtubules in gliding motility assays [1]. Gliding motility assays are assays where a glass cover slip is passivated and kinesin is prevented from interacting directly with the substrate. Microtubules are then propelled by the motor activity of a bed of immobilized kinesin molecules. Lipid molecules are fatty acids that can be purified to a much greater extent than casein can. Also, lipid molecules exhibit the same amphiphilc behavior as casein, they adhere to glass easily and, can be easily functionalized. Lipids are thus an attractive alternative to casein proteins for surface passivation. We report preliminary results on the surface passivation performance of lipid molecules in gliding motility assays.

[1] Vivek Verma, William O Hancock, Jeffrey M Catchmark, "The role of casein in supporting the operation of surface bound kinesin," J. Biol. Eng. 2008; 2: 14. PMID: 18937863

I have no idea if this is the correct way to make a reference. Sad isn't it? Steve Koch 00:33, 18 July 2009 (EDT): Yeah, that is sad, but you'll be on many papers over the next couple years. Also, it doesn't matter: the main goal is to make it as easy as possible for someone to find the paper you're talking about. Each journal has their own special format, so I wouldn't worry about. Only thing I'd add is a very simple way to find the paper, either a DOI or pub med ID. I added the Pub Med ID above. I noticed when looking at it that they have a more recent Biophys J paper that may be interesting, http://www.ncbi.nlm.nih.gov/pubmed/19383474

Steve Koch 00:33, 18 July 2009 (EDT): I think your abstract is killer and ready to go. Run it past Susan if you'd like--but be prepared for irreconcilable differences with my advice :) Also, Susan won't be able to respond until Sunday. I think it's really good as is. Good job! The only thing worrying me is what will happen if you just can't get anything to work at all? I think that's unlikely, so I think this is good.

Steve Koch 20:32, 19 July 2009 (EDT): I like the title: short and to the point, fine with me. I still like the abstract. I would keep it as one paragraph with a space before the reference. Please do submit it tonight or tomorrow morning. Thanks!

Comments

Andy Maloney 12:39, 17 July 2009 (EDT): First reading...very sexy. You sure are a much better writer than when I joined your lab.

Andy Maloney 23:23, 19 July 2009 (EDT): Submitted.