detection system for cloning chitinase gene

[Chanpen Wiwat - PYMI]

I will clone chitinase gene from Bacillus sp. using BluescriptKS vector 
and E.coli DH5 as cloning host.  I have tried to detect positive clone by 
using agar containing Carboxymethyl- chitin as substrate and stain with 
congo red.  This method can be used very well in detection chitinase 
enzyme but I cannot detect chitinase from E.coli (positive control). 
(I have exposed E.coli colony to chloroform vapour for 20 min. before 
overlay with agar containing CM-chitin.)

Please give me a protocol, if any one have tried them or any suggestions 
for the sensitive detection system.

Thanks.

Chanpen Wiwat
Department of Microbiology
Faculty of Pharmacy, Mahidol University.