https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Biological nanomotors with a revolution, linear, or rotation motion mechanism https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:29110 oF1 ATPase, helicases, viral dsDNA-packaging motors, bacterial chromosome translocases, myosin, kinesin, and dynein. In particular, dsDNA translocases are used to illustrate how these features relate to the motion mechanism and how nature elegantly evolved a revolution mechanism to avoid coiling and tangling during lengthy dsDNA genome transportation in cell division. Motor chirality and channel size are two factors that distinguish rotation motors from revolution motors. Rotation motors use right-handed channels to drive the right-handed dsDNA, similar to the way a nut drives the bolt with threads in same orientation; revolution motors use left-handed motor channels to revolve the right-handed dsDNA. Rotation motors use small channels (<2 nm in diameter) for the close contact of the channel wall with single-stranded DNA (ssDNA) or the 2-nm dsDNA bolt; revolution motors use larger channels (>3 nm) with room for the bolt to revolve. Binding and hydrolysis of ATP are linked to different conformational entropy changes in the motor that lead to altered affinity for the substrate and allow work to be done, for example, helicase unwinding of DNA or translocase directional movement of DNA.]]> Wed 11 Apr 2018 15:14:20 AEST ]]> Core@Satellite Janus Nanomotors with pH-Responsive Multi-phoretic Propulsion https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:55883 Wed 03 Jul 2024 15:00:22 AEST ]]> Core@satellite janus nanomotors with pH-responsive multi-phoretic propulsion https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38917 2O2 due to the isolation of the Au nanoparticles (AuNPs) from the PtNPs layer. Then the weak acidity of H2O2 can trigger the disassembly and reassembly of the AuNPs, resulting in the Janus distribution of large AuNPs aggregates. Such reconstruction of JMPA leads to the contact between PtNPs and AuNPs aggregates, thus changing the propulsion mechanism to self-electrophoresis. The asymmetric and aggregated AuNPs also enable the generation of a thermal gradient under laser irradiation, which propels the JMPA nanomotors by self-thermophoresis. Such multi-phoretic propulsion offers considerable promise for developing advanced nanomachines with a stimuli-responsive switch of propulsion modes in biomedical applications.]]> Wed 02 Mar 2022 15:43:14 AEDT ]]>