I27O AFM Reference Protein Data Sheet
Catalog No. 0304
I27O™ is a 94 kDa synthetic polyprotein composed of eight repeats of the I27 domain
of human titin. It is used for the calibration of and as a reference for
force extension experiments using atomic force microscopes. It is supplied in a
ready-to-use solution. Single molecule measurements give up to eight saw-tooth
force-extension curves with the specifications below. The protein has durable
elasticity that allows for repeated unfolding and refolding.
||shipped on dry ice
||10 years at - 80°C
Aliquot to avoid repeated freezing and thawing.
||1 month at 4°C
||In SSI Buffer: 50 mM Na2HPO4, 300 mM NaCl,
20 mM imidazole, pH 8.0
|Technical Information (force extension measurements)
|Distance between peaks
||24.1 ± 0.34nm
||204 ± 26pN
||0.30 ± 0.07nm
||24.1 ± 0.34nm
Instructions for Use
Dilute the stock protein solution to a concentration of 100µg/ml in PBS pH 7.3
buffer and apply the sample to freshly evaporated gold coverslips.
Attach coverslips to the piezoelectric positioner stage.
The I27O™ was engineered with an amino-terminal hex-His peptide sequence
and carboxy-terminal di-Cys. This confi guration is hypothesized to allow the
protein molecules to attach to the coverslip at the carboxy-terminal leaving the
amino-terminus free to attach to the silicon nitride cantilever tip, when the tip
is brought in close proximity to the absorbed protein. It is this model which is
believed to account for the high frequency (>50%) of observing all eight domain
extensions after each retraction as well as the ability to perform extension and
retraction experiments on a single molecule.
Material Safety Data
FOR RESEARCH USE ONLY. NOT INTENDED OR APPROVED
FOR HUMAN, DIAGNOSTICS OR VETERINARY
USE. Do not ingest, swallow or inhale. Do not get in
eyes, on skin, or on clothing. Wash thoroughly after
handling. For complete safety information see full
Material Safety Data Sheet.
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Extension Experiments. Athena Enzyme Systems™ Tech Bulletin #4,
Athena Environmental Sciences, Inc.
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single proteins. Proc. Natl. Acad. Sci. USA 96:11288-11292.