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Innovative and Advanced Motor Design
Published in Wei Tong, Mechanical Design and Manufacturing of Electric Motors, 2022
Molecular motors have some potential applications in nanomedicine, intelligent nanosystems, molecular sensors, and others. One example in engineering applications is molecular gyroscopes. According to the conservation of angular momentum, at extremely high rotating speeds, the axis of rotation of a molecular motor is free to assume any orientation by itself and thus is unaffected by its frame movement. Therefore, it is possible to design molecular gyroscopes based on molecular rotation motors. This is an important milestone in the ultra-miniaturization of gyroscopes.
Wireless Nanosensor Networks and IoNT
Published in Vinod Kumar Khanna, Nanosensors, 2021
Sub-category 2: active transport mechanisms, which consume cellular energy: Molecular motors: these motors are miniscule protein machines that harness the chemical energy released by the hydrolysis of adenosine triphosphate (ATP) to perform mechanical work for the intracellular trafficking of large molecules. The information is loaded into a container that travels along a rail and is opened at the receiver (Figure 14.3).Bacterial flagellar motors (BFM): the flagella are long, thin, helical appendages to a bacterial cell that enable their movement through their habitat. The transmitter delivers the DNA information to the bacteria, which propels toward the receiver giving it the DNA information upon contact. Figure 14.4 shows the flagellar motor.
Molecular Motors
Published in Yubing Xie, The Nanobiotechnology Handbook, 2012
Timothy D. Riehlman, Zachary T. Olmsted, Janet L. Paluh
Decades of discovery based on biological, biophysical, and structural analysis of motor proteins would not have been possible without research in a wide range of model organisms. Mechanistic studies in eukaryotes are enhanced by genetic manipulation, biochemical analysis, and time-lapse live-cell imaging and include numerous studies in yeasts (predominantly budding yeast Saccharomyces cerevisiae and fission yeast Schizosaccharomyces pombe), other fungi (including Neurospora crassa and Aspergillus nidulans), the transparent nematode Caenorhabditis elegans, the fruit fly Drosophila melanogaster, the African tree frog Xenopus laevis, and mammals (Sellers, 2000; Lawrence et al., 2004; Miki et al., 2005). Comparative analysis has been invaluable to help determine general, conserved mechanisms versus more unique or species-specific requirements in motor protein complexity. Highly conserved mechanisms reveal natural design-optimized outcomes, whereas multiple mechanisms generally reflect a high degree of flexibility and/or specialization needed in the process. Molecular motors of the cytoskeleton include the actin-binding myosin motors and microtubule-binding kinesin, kinesin-like proteins (Klps), and dynein (Figure 4.1). Many similar concepts are used in discussing these motors including conserved structural domains, monomeric or multimeric or multiprotein forms, ATP hydrolysis and force generation, processivity, active or inactive conformations, and regulation. Motility of all motors is not yet determined, but when kinetic data are present, parameters of directionality may also include back-stepping or non-uniform step sizes. These natural motors provide inspiration for a range of walking molecules to be used in combining nanotechnology with biosynthetic designs (von Delius and Leigh, 2011). In addition to these “tracking” motors, it is useful to follow related fields of study on chemical motors and non-tracking multiprotein motor complexes such as ATP synthase, the ribosome, and flagella discussed briefly herein.
Energetics of molecular motor proteins: could it pay to take a free ride?
Published in Molecular Physics, 2018
Molecular motor proteins are widely used in biological systems to generate directional motion [1]. They are used to generate actual bodily motion, such as muscle contraction, and in cells to move material from one place to another. Here, we are interested in the latter. Directed transport occurs by motor proteins binding to sites on certain semi-stiff ‘track’ filaments that are assemblies of globular proteins with a polarity. They then process in a given direction, determined by the polarity of the track. The exact mechanism by which this occurs is still a matter of debate. However, the consensus is that the motors hydrolyse ATP and undergo a configurational change that moves them along to the next binding site [2,3]. Motor proteins primarily differ in the track to which they bind and in which direction they move once bound to the track. Myosin binds to actin filaments and provides the driving force for muscle contraction. The motors proteins kinesin and dynein bind to microtubules. Once bound to the track, the former heads towards the positive end of the track and the latter towards the negative end. The end of the protein that does not bind to the track binds to ‘cargoes’, such as proteins and vesicles. Once attached, the motor with loaded cargo transports it along the track. As such, this is the mechanism behind most active transport of proteins and vesicles in the cytoplasm. On the scale of a typical cell, this transport takes place over distances in the order of microns. Directed motion over much longer scales occurs in cells such as axons (a giraffe has an axon [4] that is 2m in length, vying with the giant squid [5] for the record), where it is believed to be linked to various neural dysfunctions including Alzheimer's disease [6].
Markov modeling of run length and velocity for molecular motors
Published in Applicable Analysis, 2022
James L. Buchanan, Robert P. Gilbert
Intracellular cargo is moved along the cytoskeletal tracks by the molecular motors kinesin, dynein, and myosin. Asbury et al. [1], Muthukrishnan et al. [2], Elting et al. [3] and Shastry and Hancock [4] describe in vitro experiments in which the procession of molecular motors along microtubule tracks attached to glass plates is measured. The latter three articles give statistics on the length traversed until detachment.
Molecular swarm robots: recent progress and future challenges
Published in Science and Technology of Advanced Materials, 2020
Arif Md. Rashedul Kabir, Daisuke Inoue, Akira Kakugo
By overcoming the hurdles related to the size and number of individual molecular robots prepared from biomolecular motors, DNA, and photosensitive molecules, swarming of molecular robots have been executed as an emergent function. The size of robots has been scaled down from centimeters to nanometers, and the number of robots participating in swarming has been successfully increased from one thousand to millions. Further optimization of the molecular robots is necessary for their applications to process, store, and transmit information which are subject to future work (Figure 6). Molecular robots with more complex structures and functions or entirely new frameworks are also being considered in various combinations. For example, apart from the many efforts based on DNA and related nanostructures, there have been reports on the fabrication of peptide-based nanomaterials for artificial systems [85–87]. Being motivated by the 2016 Nobel Prize in Chemistry a great initiative has been undertaken recently for interdisciplinary collaboration to prepare hybrid molecular engine by utilizing synthetic molecular motors created based on supramolecular chemistry, DNA nanotechnology, and biological molecular motors as reported elsewhere [88]. Despite these ongoing progresses, there are several issues to address for the practical applications of molecular robots such as energy efficiency and reusability. From the perspective of sustainable development goals, it would be intriguing to take further initiatives in the future to tackle these challenges related to energy crisis [89]. On the other hand, short lifetime of the robots, particularly of the actuators, due to mechanical aging [90,91] and thermal denaturation pose big drawbacks to the molecular robots [92,93]. To make the molecular robots more sustainable further improvement is necessary to prevent the degradation or functional inactivation of the robots as inspired by using reactive oxygen species-free environment, and osmolytes, etc. [93–96]. In the long run, the molecular robots are expected to greatly contribute to the emergence of a new dimension in chemical synthesis, molecular manufacturing, and artificial intelligence based on fusion of biotechnology, nanotechnology, and informatics.