User:Gustav Vaaje-Kolstad

I obtained both my MSc (2001) and PhD (2005) in biochemistry in the group of Vincent Eijsink at the Norwegian University of Life Sciences. The main focus of my PhD project was obtaining a deeper insight into catalysis by family GH18 chitinases by combining mutagenesis, enzymology, structural biology and bioinformatic techniques [1, 2]. During this period I spent a substantial amount of time in the lab of Daan van Aalten at the Wellcome Trust Center, University of Dundee, Scotland, to learn X-ray crystallography and structural biology in general. After finishing my PhD I obtained a 3 year personal post doc grant of which one year was spent in the lab of Geoff Fincher and Maria Hrmova at the University of Adelaide, Australia, where I studied the role of family GH16 xyloglucan endotransferases (XETs) in plant cell wall remodeling [3, 4].

In the last year of my PhD period I set my mind on figuring out the role of a apparently non-catalytic protein highly expressed by the Gram negative bacterium Serratia marcescens during chitin degradation. The name of the protein was CBP21 and it was a member of Carbohydrate Binding Module Family 33. After solving the structure of the protein [5] and finding it able to boost chitin degradation by chitinases [6], we were later able to show that the protein was actually an enzyme cleaving glycosidic bonds of chitin chains by a redox-type mechanism [7]. Today, this novel enzyme activity is know as lytic polysaccharide monooxygenase (LPMO) and enzymes harbouring this activity are found in Auxiliary Activity Family 9 and Auxiliary Activity Family 10. Recent years we have put a lot of effort in figuring out how these enzymes work, where I'm primarily involved in the work on the former CBM33 family, now named AA10 [8, 9, 10].

My main scientific interest lies in understanding chitin biology with an emphasis on the molecular mechanisms of chitin degradation, especially involving family AA10 LPMOs.

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1. Vaaje-Kolstad G, Houston DR, Rao FV, Peter MG, Synstad B, van Aalten DM, and Eijsink VG. (2004). Structure of the D142N mutant of the family 18 chitinase ChiB from Serratia marcescens and its complex with allosamidin. Biochim Biophys Acta. 2004;1696(1):103-11. DOI:10.1016/j.bbapap.2003.09.014 |
2. Vaaje-Kolstad G, Vasella A, Peter MG, Netter C, Houston DR, Westereng B, Synstad B, Eijsink VG, and van Aalten DM. (2004). Interactions of a family 18 chitinase with the designed inhibitor HM508 and its degradation product, chitobiono-delta-lactone. J Biol Chem. 2004;279(5):3612-9. DOI:10.1074/jbc.M310057200 |
3. Vaaje-Kolstad G, Farkas V, Fincher GB, and Hrmova M. (2010). Barley xyloglucan xyloglucosyl transferases bind xyloglucan-derived oligosaccharides in their acceptor-binding regions in multiple conformational states. Arch Biochem Biophys. 2010;496(1):61-8. DOI:10.1016/j.abb.2010.01.011 |
4. Vaaje-Kolstad G, Farkas V, Hrmova M, and Fincher GB. (2010). Xyloglucan xyloglucosyl transferases from barley (Hordeum vulgare L.) bind oligomeric and polymeric xyloglucan molecules in their acceptor binding sites. Biochim Biophys Acta. 2010;1800(7):674-84. DOI:10.1016/j.bbagen.2010.04.001 |
5. Vaaje-Kolstad G, Houston DR, Riemen AH, Eijsink VG, and van Aalten DM. (2005). Crystal structure and binding properties of the Serratia marcescens chitin-binding protein CBP21. J Biol Chem. 2005;280(12):11313-9. DOI:10.1074/jbc.M407175200 |
6. Vaaje-Kolstad G, Horn SJ, van Aalten DM, Synstad B, and Eijsink VG. (2005). The non-catalytic chitin-binding protein CBP21 from Serratia marcescens is essential for chitin degradation. J Biol Chem. 2005;280(31):28492-7. DOI:10.1074/jbc.M504468200 |
7. Vaaje-Kolstad G, Westereng B, Horn SJ, Liu Z, Zhai H, Sørlie M, and Eijsink VG. (2010). An oxidative enzyme boosting the enzymatic conversion of recalcitrant polysaccharides. Science. 2010;330(6001):219-22. DOI:10.1126/science.1192231 |
8. Forsberg Z, Vaaje-Kolstad G, Westereng B, Bunæs AC, Stenstrøm Y, MacKenzie A, Sørlie M, Horn SJ, and Eijsink VG. (2011). Cleavage of cellulose by a CBM33 protein. Protein Sci. 2011;20(9):1479-83. DOI:10.1002/pro.689 |
9. Vaaje-Kolstad G, Bøhle LA, Gåseidnes S, Dalhus B, Bjørås M, Mathiesen G, and Eijsink VG. (2012). Characterization of the chitinolytic machinery of Enterococcus faecalis V583 and high-resolution structure of its oxidative CBM33 enzyme. J Mol Biol. 2012;416(2):239-54. DOI:10.1016/j.jmb.2011.12.033 |
10. Aachmann FL, Sørlie M, Skjåk-Bræk G, Eijsink VG, and Vaaje-Kolstad G. (2012). NMR structure of a lytic polysaccharide monooxygenase provides insight into copper binding, protein dynamics, and substrate interactions. Proc Natl Acad Sci U S A. 2012;109(46):18779-84. DOI:10.1073/pnas.1208822109 |