[3dem] Calcium free filter paper

[Hiroshi Imai]

Dear Jing

Muscle thin filaments are sensitive to calcium.
Here at University of Leeds, everyone uses ashless filter paper by following Dr. Howard White, who found that his muscle thin filaments were getting switched to the on-state by calcium in the filter paper.
You can find ashless filter paper by google search with key words, "Whatman ashless filter paper".
For example, I have used Whatman grade no.43 (ashleess filter paper) for my experiment.
The rate of water absorption differs between filter paper grades, so you may need to re-determine blotting time for a new filter paper.

I hope that this information is helpful to you.
Best wishes,
Hiroshi
______________________________________________________
Research Fellow,  Dr. Stan Burgess' and Prof. Peter
Knight's lab, Astbury Centre for Structural Molecular
Biology, and School of Molecular and Cellular Biology,
University of Leeds, Leeds, LS2 9JT, United Kingdom
______________________________________________________



From: Jing Wang <jing at bu.edu<mailto:jing at bu.edu>>
Date: Saturday, 30 August 2014 18:02
To: "rkhayat at ccny.cuny.edu<mailto:rkhayat at ccny.cuny.edu>" <rkhayat at ccny.cuny.edu<mailto:rkhayat at ccny.cuny.edu>>
Cc: "3dem at ncmir.ucsd.edu<mailto:3dem at ncmir.ucsd.edu>" <3dem at ncmir.ucsd.edu<mailto:3dem at ncmir.ucsd.edu>>
Subject: Re: [3dem] Calcium free filter paper

Thank you all for the suggestion!! I'll try soaking the filter paper with 1 mM EGTA and dry it out flat. Let you know later if it works,
Cheers,
Jing


On Fri, Aug 29, 2014 at 8:49 PM, <rkhayat at ccny.cuny.edu<mailto:rkhayat at ccny.cuny.edu>> wrote:
Hi,

How about adding EDTA to your complex to chelate the calcium,
or wash the filter paper with EDTA and let it dry in a vacuum
before use.

Best wishes,
Reza

Reza Khayat, PhD
Assistant Professor
The City College of New York
Department of Chemistry, MR-1135
160 Convent Avenue
New York, NY  10031
Tel. (212) 650-6070<tel:%28212%29%20650-6070>
www.khayatlab.org<http://www.khayatlab.org>


---- Original message ----
>Date: Fri, 29 Aug 2014 18:22:06 -0400
>From: 3dem-bounces at ncmir.ucsd.edu<mailto:3dem-bounces at ncmir.ucsd.edu> (on behalf of Jing Wang
<jing at bu.edu<mailto:jing at bu.edu>>)
>Subject: [3dem] Calcium free filter paper
>To: "3dem at ncmir.ucsd.edu<mailto:3dem at ncmir.ucsd.edu>" <3dem at ncmir.ucsd.edu<mailto:3dem at ncmir.ucsd.edu>>
>
>   Hi there,
>   I'm working with a complex of calcium sensor
>   protein, which dissembles upon exposure to calcium.
>   The complex fell apart after freezing and I
>   suspected it might due to the** residual calcium
>   from the vitrobot blotting paper. Is there a
>   commercially available calcium-free filter paper or
>   is there a protocol for cleaning up the regular
>   filter paper? Any comment will be greatly
>   appreciated!!
>   Jing
>________________
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