Cellulase Processivity

  • David B. WilsonEmail author
  • Maxim Kostylev
Part of the Methods in Molecular Biology book series (MIMB, volume 908)


There are two types of processive cellulases, exocellulases and processive endoglucanases. There are also two classes of exocellulases, ones that attack the reducing ends of cellulose chains and ones that attack the nonreducing ends. There are a number of ways of assaying processivity but none of them are ideal. It appears that exocellulases, all of which have their active sites in a tunnel, couple movement along a cellulose chain with cleavage of cellobiose from the end of the cellulose molecule. There are two sets of structures that suggest how an exocellulase might move along a cellulose chain. For family 48 exocellulases there are two different ways that a chain can be bound in the active site while for family 6 exocellulases there are several different ligand-bound structures. Site-directed mutagenesis of Thermobifida fusca exocellulases Cel48A and Cel6B and the processive endoglucanase Cel9A have identified some mutations that increase processivity and some that decrease processivity. In addition a mutation in Cel6B was identified that appears to allow the mutant enzyme to move along a cellulose chain in the absence of cleavage.

Key words

Cellulose Cellulase processivity Exocellulases Processive endoglucanases Thermobifida fusca 



This work was supported by the BioEnergy Science Center (BESC), which is a part of the U.S. Department of Energy Bioenergy Research Center supported by the Office of Biological and Environmental Research in the DOE Office of Science, Oak Ridge National Laboratory. We thank Mo Chen for preparing the figure.


  1. 1.
    Teeri TT, Koivula A, Linder M, Wohlfahrt G, Divne C, Jones TA (1998) Trichoderma reesei cellobiohydrolases: why so efficient on crystalline cellulose? Biochem Soc Trans 26:173–178Google Scholar
  2. 2.
    Barr BK, Hsieh YL, Ganem B, Wilson DB (1996) Identification of two functionally different classes of exocellulases. Biochemistry 35:586–592CrossRefGoogle Scholar
  3. 3.
    Rouvinen J, Bergfors T, Teeri T, Knowles JK, Jones TA (1990) Three-dimensional structure of cellobiohydrolase II from Trichoderma reesei. Science 249:380–386CrossRefGoogle Scholar
  4. 4.
    Divne C, Stahlberg J, Reinikainen T, Ruohonen L, Pettersson G, Knowles JKC, Teeri TT, Jones A (1994) The three-dimensional structure of the catalytic core of cellobiohydrolase I from Trichoderma reesei. Science 265:524–528CrossRefGoogle Scholar
  5. 5.
    Parsiegla G, Juy M, Reverbel-Leroy C, Tardif C, Belaich JP, Driguez H, Haser R (1998) The crystal structure of the processive endocellulase CelF of Clostridium cellulolyticum in complex with a thiooligosaccharide inhibitor at 2.0 Å resolution. EMBO J 17:5551–5562CrossRefGoogle Scholar
  6. 6.
    Sakon J, Irwin D, Wilson DB, Karplus PA (1997) Structure and mechanism of endo/exocellulase E4 from Thermomonospora fusca. Nat Struct Biol 4:810–818CrossRefGoogle Scholar
  7. 7.
    Irwin D, Shin D-H, Zhang S, Barr BK, Sakon J, Karplus PA, Wilson DB (1998) Roles of the catalytic domain and two cellulose binding domains of Thermomonospora fusca E4 in cellulose hydrolysis. J Bacteriol 180:1709–1714Google Scholar
  8. 8.
    Watson BJ, Zhang H, Longmire AG, Moon YH, Hutcheson SW (2009) Processive endoglucanases mediate degradation of cellulose by Saccharophagus degradans. J Bacteriol 191:5697–5705CrossRefGoogle Scholar
  9. 9.
    Zakariassen H, Aam BB, Horn SJ, Vårum KM, Sørlie M, Eijsink VG (2009) Aromatic residues in the catalytic center of chitinase A from Serratia marcescens affect processivity, enzyme activity, and biomass converting efficiency. J Biol Chem 284:10610–10617CrossRefGoogle Scholar
  10. 10.
    Irwin DC, Spezio M, Walker LP, Wilson DB (1993) Activity studies of eight purified cellulases: specificity, synergism, and binding domain effects. Biotechnol Bioeng 42:1002–1013CrossRefGoogle Scholar
  11. 11.
    Vuong TV, Wilson DB (2009) Processivity, synergism, and substrate specificity of Thermobifida fusca Cel6B. Appl Environ Microbiol 75:6655–6661CrossRefGoogle Scholar
  12. 12.
    Imai T, Boisset C, Samejima M, Igarashi K, Sugiyama J (1998) Unidirectional processive action of cellobiohydrolase Cel7A on Valonia cellulose microcrystals. FEBS Lett 432:113–116CrossRefGoogle Scholar
  13. 13.
    Igarashi K, Koivula A, Wada M, Kimura S, Penttilä M, Samejima M (2009) High speed atomic force microscopy visualizes processive movement of Trichoderma reesei cellobiohydrolase I on crystalline cellulose. J Biol Chem 284:36186–36190CrossRefGoogle Scholar
  14. 14.
    Harjunpää V, Teleman A, Koivula A, Ruohonen L, Teeri TT, Teleman O, Drakenberg T (1996) Cello-oligosaccharide hydrolysis by cellobiohydrolase II from Trichoderma reesei. Association and rate constants derived from an analysis of progress curves. Eur J Biochem 240:591CrossRefGoogle Scholar
  15. 15.
    Nidetsky B, Zachariae W, Gercken G, Hayn M, Steiner W (1994) Hydrolysis of cello-oligosaccharides by Trichoderma reesei cellobiohydrolases; experimental data and kinetic modeling. Enzyme Microb Technol 16:43–52CrossRefGoogle Scholar
  16. 16.
    Kurasin M, Väljamäe P (2011) Processivity of cellobiohydrolases is limited by the substrate. J Biol Chem 286:169–177CrossRefGoogle Scholar
  17. 17.
    Kipper K, Väljamäe P, Johansson G (2005) Processive action of cellobiohydrolase Cel7A from Trichoderma reesei is revealed as ‘burst’ kinetics on fluorescent polymeric model substrates. Biochem J 385:527–535CrossRefGoogle Scholar
  18. 18.
    Praestgaard E, Elmerdahl J, Murphy L, Nymand S, McFarland KC, Borch K, Westh P (2011) A kinetic model for the burst phase of processive cellulases. FEBS J 10.1111/j.-1742-4658Google Scholar
  19. 19.
    Parsiegla G, Reverbel C, Tardif C, Driguez H, Haser R (2008) Structures of mutants of cellulase Cel48F of Clostridium cellulolyticum in complex with long hemithiocello oligosaccharides give rise to a new view of the substrate pathway during processive action. J Mol Biol 375:499–510CrossRefGoogle Scholar
  20. 20.
    Varrot A, Frandsen TP, von Ossowski I, Boyer V, Cottaz S, Driguez H, Schülein M, Davies GJ (2003) Structural basis for ligand binding and processivity in cellobiohydrolase Cel6A from Humicola insolens. Structure 11:855–864CrossRefGoogle Scholar
  21. 21.
    Li Y, Irwin DC, Wilson DB (2007) Processivity, substrate binding, and mechanism of cellulose hydrolysis by Thermobifida fusca Cel9A. Appl Environ Microbiol 73:3165–3172CrossRefGoogle Scholar
  22. 22.
    Guimarães BG, Souchon H, Lytle BL, Wu D, Alzari PM (2002) The crystal structure and catalytic mechanism of cellobiohydrolase CelS, major enzymatic component of the Clostridium thermocellum cellulosome. J Mol Biol 320:587–596CrossRefGoogle Scholar
  23. 23.
    Vuong TV, Wilson DB (2009) The absence of a single identifiable catalytic base residue in Thermobifida fusca exocellulase Cel6B. FEBS J 276:3837–3845CrossRefGoogle Scholar
  24. 24.
    Koivula A, Kinnari T, Harjunpää V, Ruohonen L, Teleman A, Drakenberg T, Rouvinen J, Jones TA, Teeri TT (1998) Tryptophan 272: an essential determinant of crystalline cellulose degradation by Trichoderma reesei cellobiohydrolase Cel6A. FEBS Lett 429:341–346CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of Molecular Biology & GeneticsCornell UniversityIthacaUSA

Personalised recommendations