3R57. Mechanics of Motor Proteins and the Cytoskeleton. - J Howard (Dept of Physiology and Biophys, Univ of Washington, Seattle WA). Sinauer Assoc Inc, Sunderland MA. 2001. 367 pp. ISBN 0-87893-334-4. $59.95.
Reviewed by RL Clark (Dept of Mech Eng and Mat Sci, Duke Univ, 301 Hudson Eng Center, PO Box 90300, Durham NC 27708).
The introduction of this text is timely with regard to current interest in nanoscience and nanoengineering. A recent article, “The Little Engines That Couldn’t,” (Peter Weiss, Science News, July 22, 2000), reveals that “early enthusiasts didn’t anticipate the powerful forces that arise at the surfaces of micromachines.” In particular, components of such devices intended to move, such as miniature gears in micro-electro-mechanical systems (MEMS), tend to stick together because of van der Waals and other molecular forces. This problem results from attempts made to “miniaturize” conventional engineering systems without consideration of changes in forces that dominate at these different scales (inertial versus viscous for example). In contrast, nature scales up when “engineering” systems and works within an aqueous environment for the most part. This textbook provides a wonderful perspective for mechanics at the scale of a single protein molecule where dimensions are measured in nanometers and forces are measured in picoNewtons.
The author of this text does an outstanding job in developing a book for a broad audience, inclusive of biologists, physicists, and engineers. The book is aimed at an introduction to the mechanics of molecules and the application of this knowledge to the morphology and motility of cells. This aim is readily achieved within this text, which is well suited as an introductory graduate course for the intended audience.
The book is well organized into three primary parts: Physical Principles, Cytoskeleton, and Motor Proteins. If an engineer is interested in nothing more than gaining insight into the relevant physics at the molecular level, then the book is worth purchasing simply for the well-written section devoted to Part I: Physical Principles. Within this section, mechanical forces; mass, stiffness, and damping of proteins; thermal forces and diffusion; chemical forces; and polymer mechanics are all discussed. The mathematical treatment within the chapters is sufficient to provide perspective; however the specifics of the mathematical developments are detailed for the reader with more inclination for such in the appendices.
The author does an outstanding job in providing figures that readily convey the pertinent concepts. Furthermore, there are numerous examples which succeed in conveying insight into the mechanics at the molecular scale as well as perspective of dimensional units. These examples provide a much needed bridge between the terminology used in biology and that used in engineering.
Part II and Part III of the text provide context for the structure, mechanics, and polymerization of cytoskeleton filaments and also provide specifics of force generation and active polymerization. This is essential background for detailing the structure of the motor proteins, including parameters such as speed, steps, and forces. The operation of these nanomachines, manufactured by nature, provides much motivation and insight for engineers.
Mechanics of Motor Proteins and the Cytoskeleton will take permanent residence on this reviewer’s shelf due to a personal interest in mechanics at this scale, and this reviewer would highly recommend it to those with interest in or currently involved in the analysis or development of micro-electro-mechanical systems or nano-electro-mechanical systems.
