Substrate binding of a family GH19 chitinase from a moss species,
Bryum coronatum(BcChi-A, 22 kDa), which is smaller than the 26 kDa
family GH19 barley chitinase due to the lack of several loop regions (‘loop-less’), was investigated by oligosaccharide digestion, thermal unfolding
experiments and isothermal titration calorimetry (ITC).
We present a comparative study of ChiA, ChiB, and ChiC, the three family
18 chitinases produced bySerratia marcescens. All three enzymes eventu-ally converted chitin to N-acetylglucosamine dimers (GlcNAc2) and a
minor fraction of monomers. ChiC differed from ChiA and ChiB in that it
initially produced longer oligosaccharides from chitin and had lower activ-ity towards an oligomeric substrate, GlcNAc6.