उपन्यास गुरुत्वीय फोर्स स्पेक्ट्रोमीटर का उपयोग करता है दिखाते खींचो और रेशेदार प्रोटीन उपाय
Summary
इस एक कदम से कदम गाइड उद्देश्य, संचालन, और उपन्यास गुरुत्वाकर्षण बल स्पेक्ट्रोमीटर से प्रतिनिधि परिणाम दिखा है.
Abstract
The study of macromolecular structure has become critical to the elucidation of molecular mechanisms and function. There are several limited, but important bioinstruments capable of testing the force dependence of structural features in proteins. Scale has been a limiting parameter on how accurately researchers can peer into the nanomechanical world of molecules, such as nucleic acids, enzymes, and motor proteins that perform life-sustaining work. Atomic force microscopy (AFM) is well tuned to determine native structures of fibrous proteins with a distance resolution on par with electron microscopy. However, in AFM force studies, the forces are typically much higher than a single molecule might experience 1, 2. Optical traps (OT) are very good at determining the relative distance between the trapped beads and they can impart very small forces 3. However, they do not yield accurate absolute lengths of the molecules under study. Molecular simulations provide supportive information to such experiments, but are limited in the ability to handle the same large molecular sizes, long time frames, and convince some researchers in the absence of other supporting evidence2, 4.
The gravitational force spectrometer (GFS) fills a critical niche in the arsenal of an investigator by providing a unique combination of abilities. This instrument is capable of generating forces typically with 98% or better accuracy from the femtonewton range to the nanonewton range. The distance measurements currently are capable of resolving the absolute molecular length down to five nanometers, and relative bead pair separation distances with a precision similar to an optical trap. Also, the GFS can determine stretching or uncoiling where the force is near equilibrium, or provide a graded force to juxtapose against any measured structural changes. It is even possible to determine how many amino acid residues are involved in uncoiling events under physiological force loads 2. Unlike in other methods where there is extensive force calibration that must precede any assay, the GFS requires no such force calibration 5. By complementing the strengths of other methods, the GFS will bridge gaps in understanding the nanomechanics of vital proteins and other macromolecules.
Protocol
Discussion
जब एक डिजिटल thresholded प्रतिनिधित्व करने के लिए एक फिल्म में परिवर्तित, यह thresholded छवि के लिए वीडियो के हर फ्रेम में एक ही क्षेत्र को बनाए रखने के लिए महत्वपूर्ण है. क्योंकि एक मनका जोड़ी में मोतियों कदम एक दूसर?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
इस सामग्री को अनुदान नंबर 0842736 के तहत राष्ट्रीय विज्ञान फाउंडेशन द्वारा समर्थित काम पर आधारित है.
Materials
| Material Name | Type | Company | Catalogue Number | Comment |
|---|---|---|---|---|
| 3-Aminopropyltriethoxysilane | Poly Sciences | 919-30-2 | ||
| Acetone | Fisher Scientific | A18P-4 | ||
| Pyridine | Sigma Aldrich | 110-86-1 | ||
| Glutaraldehyde | Fisher Scientific | G7776 | ||
| Glycine | Research Organics | BP381-1 | ||
| Tris | Sigma | 9682T | ||
| Sodium azide | Amresco | 71289 | ||
| BSA | Sigma Aldrich | AMR-0332-100G | ||
| NaCl | Sigma | S7653 | ||
| EDTA | MSI | E9884 | ||
| Nitrocellulose | Sigma | 60443 | ||
| N-N Dimethyl Formamide | Extracted from Large New | D4254 | ||
| Rabbit skeletal myosin II | Zealand White Rabbits (7-8) | NA | ||
| MF30 antibody (9-10) | Developmental Studies | MF30 | ||
| MF20 antibody (6) | Hybridoma Bank | MF20 | ||
| Lab microscope | Boreal | WW57905M00 | ||
| Equatorial mount | Celestron | CG-5 | ||
| Digital video cam | Sony | XCDV60 | ||
| Caliper release | Cabelas | IA-415482 | ||
| Compression spring | Jones Spring Co. | 723 | ||
| Extension spring | Jones Spring Co. | 770 | ||
| ImageJ | NIH | NA | ||
| Fire-i drivers & application | Unibrain | 3.80 | ||
| Excel | Microsoft | NA |
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