All living species, from the simplest bacteria to the most complex plant or animal requires motor molecules to carry out essential life processes.
ATP Synthase. ATP is the universal "battery" of life. The very earliest bacteria produced ATP as part of photosynthesis. In eukaryotes, mitochondria produce ATP. Both involve ATP synthase, which is a rotary motor. The motor is embedded in a membrane and operates electrically, by a flow of protons. All known species of life use ATP to store energy which then energizes various cellular activities.
Motors used in connection with DNA and genes. These motors are found in all living species, both bacteria and Eukaryotes:
* Motors involved in gene copying:Motors used for cargo transport within a eukaryotic cell:
• Helicases separate the double-strand DNA in preparation for transcription* Motors involved in maintenance of the DNA:
• RNA polymerase transcribes one of the DNA strands to form mRNA (messenger RNA) as the first step in copying a gene to form proteins.
• Ribosomes read the mRNA and build a protein chain of amino acids.
• Topoisomerases unpack DNA chromosomes to form the DNA helix
• SMC proteins pack DNA helix into the tight chromosome bundles.
• Helicases duplicate DNA for replication (meiosis or mitosis).
• Kinesin and Dynein move cargo along the cytoskeleton between organelles and the cell wall
• Actin motors move along microfiliaments (another kind of skeletal structure).
• Myosin motors are used to contract skeletal muscle fibers.
All of these motors involve exceedingly complex and tightly designed molecular structures. It is (in my view) incredible to imagine that they could have formed by pure undirected chance.
References for these molecular machines are:
Peter M. Hoffmann, Life's Ratchet: How Molecular Machines Extract Order from Chaos Basic Books (2012). This book describes the various motor molecules, how they were discovered and how their operation can be viewed using modern microscopic devices that can probe down to the sub-nanometer scales of individual molecules.
Ronald D. Vale, The Molecular Motor Toolbox for Intrcellular Transport Cell Press (2003)