Odd chitinases

[Kambiz Mousavi]

I just read your letter and I think that you might be able to help me. I am
looking for information on chitinase activity (where is it found in the
lepidopterans?) and also on the pH of the concerned digestive  compartment . I
need this information for my molecular evolution project on digestive enzyme
adaptation to high pH. It seems that chitinases doesn't follow the same pattern
as the other digestive enzymes.

Thank You
Jean-Simon Diallo, University of Ottawa
jsdiallo at yahoo.com

Chip Taylor wrote:

> Here is the reference to chitinase activity associated with Bt strains
> which I promised to produce in an earlier posting.
>
> Sampson, M. N. and G. w. Gooday 1998. Involvement of chitinases of Bacillus
> thuringieensis during pathogenesis in insects. Microbiology 144: 2189-2194.
>
> -----------------------------------------------------------------------
> 4)  Bt toxin does not act as a chitinase!  It must be ingested and works in
> the insect gut.
>
> I have seen two references - which I'm unable to lay my hands on at this
> moment but I'll try to find them Mond. - that refered to some Bt toxins as
> chitinases. This surprised me as I didn't remember that there was any
> chitin in the lep gut. But there is - the peritrophic membrane is composed
> of chitin, in part, and this is the first barrier that must be breached.
>
> Monarch Watch
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