Till, M., Goldstone, D. C., Attwood, G. T., Moon, C. D., Kelly, W. J., & Arcus, V. L. (2013). Structure and function of an acetyl xylan esterase (est2a) from the rumen bacterium Butyrivibrio proteoclasticus. Proteins: Structure, Function, and Bioinformatics, 81(5), 911-917.
Permanent Research Commons link: http://hdl.handle.net/10289/7157
Butyrivibrio proteoclasticus is a significant component of the microbial population of the rumen of dairy cattle. It is a xylan-degrading organism whose genome encodes a large number of open reading frames annotated as fibre-degrading enzymes. We have determined the three-dimensional structure of Est2A, an acetyl xylan esterase from B. proteoclasticus, at 2.1 Å resolution, along with the structure of an inactive mutant (H351A) at 2.0 Å resolution. The structure reveals two domains - a C-terminal SGNH domain and an N-terminal jelly-roll domain typical of CE2 family structures. The structures are accompanied by experimentally determined enzymatic parameters against two model substrates, para-nitrophenyl acetate and para-nitrophenyl butyrate. The suite of fibre-degrading enzymes produced by B. proteoclasticus provides a rich source of new enzymes of potential use in industrial settings.