Single-Molecule Analysis of the Rotation of F1-ATPase under High Hydrostatic Pressure

Since the discovery of Single-Molecule Magnets (SMMs) in 1993 there has been extensive interest in understanding, developing and tuning the nature of magnetic interactions within SMMs with the intention of gaining greater insight into the nature of these interactions.[1] Typically this is done synthetically using variations in ligand geometry and co-ordination environment to vary magnetic behaviour. More recently it has been demonstrated that high hydrostatic pressure are also an effective mechanism for "tuning" properties such as magnetic susceptibility in a variety of SMMs.[2] The number of studies utilising high hydrostatic pressure to investigate molecular magnetism is extremely limited due to their inherent difficulty however we report a new study investigating the pressure tunabilty of Re(IV) based SMMs. 4d and 5d metal ions such as Re are of interest due their enhanced magnetic exchanges relative to their 3d analogues and Re(IV) based complexes are of particular interest. Previous studies into [ReX6]2-(X = Cl, Br and I) anions demonstrate significant antiferromagnetic coupling, not transmitted through chemical interactions but rather through weak Re-X...X interactions in the solid state which may be easily perturbed at high pressure. [3] Therefore we report an investigation into the tunability of magnetic susceptibility in a variety of [ReX4] based compounds using high pressure magnetic susceptibility measurements and correlate the results with structure observations taken from high pressure single crystal X-ray diffraction experiments. The effects of the removal of solvent trapped in the lattice using temperature and vacuum and the corresponding effect on magnetic behaviour and chemical structure are also reported.

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Development and Analysis of Multi-Laminar Chemical Delivery Platform Toward Single Molecular Application

ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels, Parts A and B ◽

10.1115/icnmm2006-96164 ◽

2006 ◽

Author(s):

Sangwook Lee ◽

Takatoki Yamamoto ◽

Shigeki Segawa ◽

Kimura Hiroshi ◽

Hiroyuki Noji ◽

...

Keyword(s):

Delivery System ◽

Single Molecule ◽

Microfluidic System ◽

F1 Atpase ◽

Chemical Delivery System ◽

System A ◽

Solution Exchange ◽

Delivery Platform ◽

Arbitrary Location ◽

Single Molecule Analysis

The fluidic operations in microfluidic system such as chemical delivery, solution exchange, and chemical reactions by mixing are one of the most important technical issues to realize high-throughput and automated chemical / biochemical analysis with extremely small amount of species down to single molecular level. In order to realize such fluidic operations in micro and nano scale, we have been trying to develop a chemical delivery system to transport reagents to an arbitrary location in microchannel. In this work, we have developed and demonstrated a chemical delivery system in microchannel using precisely controlled multilaminar flow created by our previously developed multi-channel micropump embedded on the system. As a demonstration of the chemical delivery system, a single-molecule analysis of ATP dependent rotation of F1- ATPase was investigated. As a result, ATP dependent rotation of F1-ATPase was successfully investigated by addressing one of the streams, which are included or not included ATP, to the immobilized single-molecule of F1-ATPase.

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Single-molecule imaging at high hydrostatic pressure

Applied Physics Letters ◽

10.1063/1.4802202 ◽

2013 ◽

Vol 102 (15) ◽

pp. 154103 ◽

Cited By ~ 9

Author(s):

Hugh Vass ◽

S. Lucas Black ◽

Cristina Flors ◽

Diarmuid Lloyd ◽

F. Bruce Ward ◽

...

Keyword(s):

Hydrostatic Pressure ◽

Single Molecule ◽

High Hydrostatic Pressure ◽

Single Molecule Imaging

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Single-molecule analysis of peroxisome proliferator-activated receptor [gamma]2 and [alpha] reveal subtype specific differences in chromatin binding dynamics

Endocrine Abstracts ◽

10.1530/endoabs.54.p1 ◽

2018 ◽

Author(s):

Rikke AM Jensen ◽

Ville Paakinaho ◽

Diego M Presman ◽

Erin E Swinstead ◽

R Louis Schiltz ◽

...

Keyword(s):

Single Molecule ◽

Peroxisome Proliferator ◽

Chromatin Binding ◽

Peroxisome Proliferator Activated Receptor ◽

Single Molecule Analysis

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Survival of mouse blastocysts after low-temperature preservation under high pressure

Acta Veterinaria Hungarica ◽

10.1556/avet.52.2004.4.10 ◽

2004 ◽

Vol 52 (4) ◽

pp. 479-487 ◽

Cited By ~ 7

Author(s):

Cs. Pribenszky ◽

M. Molnár ◽

S. Cseh ◽

L. Solti

Keyword(s):

Phase Transition ◽

Hydrostatic Pressure ◽

Low Temperature ◽

High Hydrostatic Pressure ◽

Room Temperature ◽

Freezing Point ◽

Significant Loss ◽

Embryo Cryopreservation ◽

Subzero Temperatures ◽

Survival Capacity

Cryoinjuries are almost inevitable during the freezing of embryos. The present study examines the possibility of using high hydrostatic pressure to reduce substantially the freezing point of the embryo-holding solution, in order to preserve embryos at subzero temperatures, thus avoiding all the disadvantages of freezing. The pressure of 210 MPa lowers the phase transition temperature of water to -21°C. According to the results of this study, embryos can survive in high hydrostatic pressure environment at room temperature; the time embryos spend under pressure without significant loss in their survival could be lengthened by gradual decompression. Pressurisation at 0°C significantly reduced the survival capacity of the embryos; gradual decompression had no beneficial effect on survival at that stage. Based on the findings, the use of the phenomena is not applicable in this form, since pressure and low temperature together proved to be lethal to the embryos in these experiments. The application of hydrostatic pressure in embryo cryopreservation requires more detailed research, although the experience gained in this study can be applied usefully in different circumstances.

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