The chitinolytic machinery of Serratia marcescens--a model system for enzymatic degradation of recalcitrant polysaccharides

FEBS J. 2013 Jul;280(13):3028-49. doi: 10.1111/febs.12181. Epub 2013 Mar 7.


The chitinolytic machinery of Serratia marcescens is one of the best known enzyme systems for the conversion of insoluble polysaccharides. This machinery includes four chitin-active enzymes: ChiC, an endo-acting non-processive chitinase; ChiA and ChiB, two processive chitinases moving along chitin chains in opposite directions; and CBP21, a surface-active CBM33-type lytic polysaccharide monooxygenase that introduces chain breaks by oxidative cleavage. Furthermore, an N-acetylhexosaminidase or chitobiase converts the oligomeric products from the other enzymes to monomeric N-acetylglucosamine. Here we discuss the catalytic mechanisms of these enzymes as well as the structural basis of each enzyme's specific role in the chitin degradation process. We also discuss how knowledge of this enzyme system may be extrapolated to other enzyme systems for conversion of insoluble polysaccharides, in particular conversion of cellulose by cellulases and GH61-type lytic polysaccharide monooxygenases.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism*
  • Biocatalysis
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Chitin / chemistry
  • Chitin / metabolism*
  • Chitinases / chemistry
  • Chitinases / metabolism*
  • Fungal Proteins / chemistry
  • Fungal Proteins / metabolism
  • Glycoside Hydrolases / chemistry
  • Glycoside Hydrolases / metabolism
  • Hydrolysis
  • Intracellular Signaling Peptides and Proteins
  • Isoenzymes / chemistry
  • Isoenzymes / metabolism
  • Models, Molecular*
  • Molecular Conformation
  • Plant Proteins / chemistry
  • Plant Proteins / metabolism
  • Polysaccharides / chemistry
  • Polysaccharides / metabolism
  • Serratia marcescens / enzymology*
  • Substrate Specificity


  • Bacterial Proteins
  • Carrier Proteins
  • Fungal Proteins
  • Intracellular Signaling Peptides and Proteins
  • Isoenzymes
  • Plant Proteins
  • Polysaccharides
  • chitin-binding protein 21, Serratia marcescens
  • Chitin
  • Glycoside Hydrolases
  • Chitinases