[Histonet] Re: Methanol in H2O2 explanation

[C.M. van der Loos]

Hi,

There is a paper from 1972 (!) by Streefkerk entitled: "Inhibition of erythrocyte pseudoperoxidase activity by treatment with hydrogen peroxidase following methanol. JHC 30:504. So perhaps the origin of methanol is not that mysterious.

I cannot imagine that methanol is still considered for cryo's when performing IHC: it certainly kill many epitopes!



Cheers, Chris



Chris van der Loos

Academic Medical Center

Dept. of Pathology

Amsterdam

The Netherlands



Date: Wed, 11 Jul 2012 20:22:38 +0200
From: "Gudrun Lang" <gu.lang <@t> gmx.at>
Subject: [Histonet] Re: Methanol in H2O2 explanation
To: <histonet <@t> lists.utsouthwestern.edu>
Message-ID: <000f01cd5f92$271cb870$75562950$@gmx.at>
Content-Type: text/plain;       charset="iso-8859-1"

Ha! I've found it. It can be found in Dr. Kiernan's book in the chapter
enzymehistochemistry - the thing, that an electron-donator is used for
demonstration.
 And he states, that methanol alone also inhibits peroxidase - perhaps by
the fixation = denaturation effect on the protein?

In the following publication one can see the equations for the
peroxidase-reaction and this phrase:
"In this study, we have used a steady state kinetics approach to demonstrate
that MPO is irreversibly inactivated by excess H2O2 in the absence of
reducing substrate."
The Open Enzyme Inhibition Journal, 2009, 2, 28-35 Mechanism-Based
Inhibition of Myeloperoxidase by Hydrogen Peroxide: Enhancement of
Inactivation Rate by Organic Donor Substrates

It's rather exhausting to prove the own statements  ;-) puh.

Gudrun


De informatie opgenomen in dit bericht kan vertrouwelijk zijn en is uitsluitend bestemd voor de geadresseerde. Indien u dit bericht onterecht ontvangt, wordt u verzocht de inhoud niet te gebruiken en de afzender direct te informeren door het bericht te retourneren. Het Academisch Medisch Centrum is een publiekrechtelijke rechtspersoon in de zin van de W.H.W. (Wet Hoger Onderwijs en Wetenschappelijk Onderzoek) en staat geregistreerd bij de Kamer van Koophandel voor Amsterdam onder nr. 34362777. De Algemene Inkoop Voorwaarden van het AMC zijn van toepassing op en maken integraal onderdeel uit van alle rechtsbetrekkingen, daaronder mede verstaan alle inkoop opdrachten en overeenkomsten, tussen AMC en derden. Deze voorwaarden zijn te raadplegen op www.amc.nl en worden op verzoek toegezonden.

________________________________

This message may contain confidential information and is intended exclusively for the addressee. If you receive this message unintentionally, please do not use the contents but notify the sender immediately by return e-mail. Academic Medical Center is a legal person by public law and is registered at the Chamber of Commerce for Amsterdam under no. 34362777. The AMC General Purchase Terms constitute an integral part of all legal relations, including but not limited to all purchase orders and contracts, between the AMC and third parties. These terms can be downloaded at the website www.amc.nl and will be sent to you at your request.