Machinery has given mankind the power to build skyscrapers, roads, canals, automobiles, computers and even space ships. Although the most precise machinery made by humans has been made most recently, humans have been using tools to build machines for at least several millennia. From wheels and levers to central processing units, we have come a long way in both the theory and application of mechanical engineering. This help that we get from our mechanical creations is perhaps the most obvious difference between us and the other life with whom we share our planet. Still, even with our great technological advancements we can not turn sunlight into sugar nearly as efficiently as the most primitive photosynthetic plants.
What kind of advanced technological machinery do these plants have? I call it "molecular machinery," or "nanomachines." Nanomachines are analogous to the airplanes, cars, and watches that we are familiar with, except in one fundamental way. While the components assembled into modern day machines are large pieces of metal, plastic, rubber and other materials, the components of nanomachines are single molecules. This means that the forces that hold together each part of a nanomachine are strong covalent bonds, while the forces holding the entire nanomachine together are "weak interactions" such as hydrogen bonds, London dispersion forces, hydrophobic effects and more.
In numerous cases, components of molecular machinery present in nature are similar to macroscopic components that we are already familiar with. In the first paper on "molecular nanotechnology," Eric Drexler presented a table of similarities between macroscopic and microscopic components. This is convenient since modern day engineers, whom have experience building machines out of defined components, can now be recruited into nanotechnology.
