Molecular motors play key roles URLanizing the interior of cells. An ideal motor would translocate cargos with a high speed and a minimal error in transport distance (or time) , while consuming minimal amount of energy. The travel distance and its variance of motor are, however,  constrained by energy consumption, the physical principle of which has recently been formulated into the thermodynamic uncertainty relation. Here, we reinterpret the themodynamic uncertainty relation to define the efficiency of a motor in cargo transport . By analyzing the existing motility data of several types of molecular motors , we calculate the energetic cost (or efficiency) of generating time traces of a given precision. The energetic cost for kinesin-1 varies nonmonotonically with ATP concentration and load (f) , and is locally minimized at [ATP] \approx 200 \muM and f\approx 4 pN. Remarkably,  this local minimum vanishes and the cost increases significantly for a mutant that has a longer neck-linker , which underscores the importance of molecular structure in transport properties. Calculations show that the energetic cost and precision of motility also vary depending on the motor type. For the biological motors studied here, the efficiency of motor is effectively optimized under cellular condition ([ATP] \approx 1 mM, f=0-1 pN). We find that among the motors, kinesin-1 at single molecule level is the most efficient in cargo transport.
Molecular motors play key roles URLanizing the interior of cells. An efficient motor in cargo transport would travel with a high speed and a minimal error in transport time (or distance) while consuming minimal amount of energy. The travel distance and its variance of motor are, however, physically constrained by energy consumption, the principle of which has recently been formulated into the thermodynamic uncertainty relation. Here, we reinterpret the uncertainty measure (\mathcal{Q in cargo transport is characterized with a small \mathcal{Q several types of molecular motors show that \mathcal{Q ATP concentration and load (f) . For kinesin-1, \mathcal{Q is locally minimized at [ATP] \approx 200 \muM and f\approx 4 pN. Remarkably, for the mutant with a longer neck-linker this local minimum vanishes , and the energetic cost to achieve the same precision as the wild-type increases significantly , which underscores the importance of molecular structure in transport properties. For the biological motors studied here, their value of \mathcal{Q cellular condition ([ATP] \approx 1 mM, f=0-1 pN). We find that among the motors, kinesin-1 at single molecule level is the most efficient in cargo transport.
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ideal motor would translocate cargos
efficient motor in cargo transport would travel
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distance (or time) ,
time (or distance)
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physically
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physical
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themodynamic uncertainty relation to define the efficiency of a motor
uncertainty measure (\mathcal{Q
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. By analyzing the existing motility data of
is characterized with a small \mathcal{Q
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, we calculate the energetic cost (or efficiency) of generating time traces of a given precision. The energetic cost for kinesin-1 varies nonmonotonically with
show that \mathcal{Q
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, and
. For kinesin-1, \mathcal{Q
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for the mutant with a longer neck-linker
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and the cost increases significantly for a mutant that has a longer neck-linker
, and the energetic cost to achieve the same precision as the wild-type increases significantly
D
Calculations show that the energetic cost and precision of motility also vary depending on the motor type.
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the efficiency of motor is effectively optimized under
their value of \mathcal{Q