Methyl mercury treatment

[Bradley Turner]

hutchins at fiona.umsmed.edu (Jim Hutchins) wrote on 
 29 Sep 1995 02:57:57 GMT in message
 <44fnbl$5a at fiona.umsmed.edu>

>OK, we all know (or should know) how the incredibly toxic compound methyl
>mercury renders all nucleic acids single-stranded.  (BTW, it works great
>for mRNA preparation for RT in library production, improved our yield 
>10-fold.)
>
>The question is, HOW does it work?  No one seems to know.
>
>You can send me a reference if you have one, I just need a pointer to the
>primary literature.
>
>
>--
>Jim Hutchins
>Assoc Prof Anatomy, Asst Prof Neurology (Research), Univ Mississippi Med Ctr
>http://fiona.umsmed.edu/~hutchins/    ***    E-mail:   hutchins at umsmed.edu
>``It became necessary to destroy the town in order to save it.''--American
>infantry officer firing on Ben Tre, Vietnam, 2/8/68
>
>

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You should find the following references helpful:

1.  Complexing and denaturation of DNA by methylmercuric hydroxide:
     1. spectrophotometric studies.
    DW Gruenwedel, N Davidson
    Journal of Molecular Biology 21:129-144, 1966

2.  Methylmercury as a reversible denaturing agent for
    agarose gel electrophoresis.
    JM Bailey, N Davidson
    Analytical Biochemistry 70:75-85, 1976

3.  Association constants of methylmercuric and mercuric ions
    with nucleosides.
    RB Simpson
    Journal of the American Chemical Society 86:2059-2065, 1964

4.  Gel electrophoretic fractionation of RNAs by partial denaturation
    with methylmercuric hydroxide.
    PM Chandler, D Rimkus, N Davidson
    Analytical Biochemistry 99:200-206, 1979

5.  Use of CH3HgOH-agarose gels for the electrophoresis of
    heterogeneous nuclear RNA and messenger RNA from mammalian cells.
    IH Maxwell, F Maxwell, WE Hahn
    Analytical Biochemistry 99:146-160, 1979

Reference 4 above summarizes references 1 & 3 above as follows:

"MMH [methylmercuric hydroxide] denatures RNA (or DNA) primarily
 by displacement of hydrogen atoms of the imino NH groups of
 uridine (U) (or thymidine (T)) and guanosine (G) residues."

I hope this helps.
And yes, Methyl mercury compounds are quite toxic:

 A review of the toxicity of methylmercury compounds with applications
 to occupational exposures associated with laboratory uses.
 RP Junghans
 Environmental Research 31:1-31, 1983

I Hope that this is helpful
Best Regards,
Brad Turner
 

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                    Bradley Turner
                 University Hospital

Boston University           PHONE: 617-638-8346
Medical Center              FAX:   617-638-7785
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