MAX-PLANCK-INSTITUT FUR PHYSIKALISCHE CHEMIE

Hcinrich Mi.ildner

3400 Gijttingen, den   11-3-69
     BunsenstraBe 10
    Tel. (0551) 44051

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Dear Dr. Rtrenbcrg,

with stperate.mail I will send you next week new preparations
of the commercially available Vibrio cholerat-sialidase and

different testsubstances.

At the moment we have two pure sialidases.the one I have

already mentioned which hydrolizes both 2 - 6' and 2 - 3'
linkages of sialic acid to carbonyarates.Ana another one
from influenea A2 virus which readlly splits only 2 - 3'
linkages.This is the characteristic feature of myxovirus

sialidases.

In all (7) isolated acidic oligosaccharides we find 4 types
of bonds through which the sialic acid residues are linked

to the oarbohgdrate:

Type I 2 - 3 linkage to galactose
                                   >
    IX 2-6 =        n        w

   III 2 - 6 n     w hexosaming
  IV Z- 8 W o   from sialic acid to sialic acid


?/Jac- i,,e
\ Y',         Type I in gangliosides,fetuin

i, .&.>.

I<
\      (JbC'?& 567 1964) and acidic

i
i
i       -
      `,- .A ;Le  L.i L- i: nc2-glycoproteins from human s 'm
J         (BBA 49 250 1961).




\,          Type III  in submaxillaris mucin

t '
i          (BBA 38 513 1960)

`l

I   x.,L(L~ .~=c: Type IV in gangliaside III and IV

i         and colominic acid (polymeric sia-

/

lit acid)(Biochem. 3 24"8 1964).
                         -

As you can see the sialidase we will send splits all these
bonds.Only type IV makes some difficulties because in addition

to the 2 - 8 linkage a 1 - 9 labile ester linkage can easily

be formed and prevent the enzyme to split the 2 - 8 linkage.
In these cases one has to open the labile ester linkage first
with n/100 NaOH (few minutea).There are ,of course other diffi-
culties WG are just locking for and I shall tell you later.
I came back for some weeks to prepare larger amounts of our
ATPase which is active on bilayer.1 think I will return in
spring and hope to see you then and give a talk.
Thank you very much again for this valuable InProduction to
the nerve growth factor.

Sincerly yours
$L -<--i /L,:(: /.Ld

(Heinrich MUdneT)

Manfred-,Eigen sends his regards.