Paper accepted: “A carbohydrate binding module-5 is essential for oxidative cleavage of chitin by a multi-modular lytic polysaccharide monooxygenase from Bacillus thuringiensis serovar kurstaki.”

Our second paper this year is a collaborative work with our partner lab at Hyderabad University in India, with the group of Prof. Appa Rao Podile. This is a project of Manjeet Kaur supported by Dr. Jogi Madhuprakash, who both spent some time in our lab during their PhD in the framework of our Indo-German International Research Training Group on Molecular and Cellular Glyco-Sciences - MCGS. Manjeet also collaborated with Dr. Michael Mormann from the Institute of Hygiene of our university, our trusted partner in difficult mass spec analyses. Her work which has now been accepted for publication in the International Journal of Biological Macromolecules deals with a novel lytic chitin monooxygenase which has a separate chitin binding module. Crystalline biopolymers such as cellulose or chitin are difficult substrates for degrading enzymes such as cellulases and chitinases. Two strategies are known to overcome this problem. First, the hydrolytic domains of such enzymes may be attached to substrate binding domains increasing enzyme-substrate affinity and, thus, enzyme activity. Alternatively, lytic polysaccharide monooxygenases may first oxidatively cleave glycosidic bonds at the surface of the polymer crystal, thus creating access points for the hydrolases. In the current enzyme, both strategies are combined: a lytic chitin monooxygenase is attached to a chitin binding domain. An interesting addition to our emerging picture of biodegradation of recalcitrant biopolymers such as chitin, and one with biotechnological potential.