Crystal structure of exo-rhamnogalacturonan lyase from Penicillium chrysogenum as a member of polysaccharide lyase family 26

FEBS Lett. 2018 Apr;592(8):1378-1388. doi: 10.1002/1873-3468.13034. Epub 2018 Mar 30.

Abstract

Exo-rhamnogalacturonan lyase from Penicillium chrysogenum 31B (PcRGLX) was recently classified as a member of polysaccharide lyase (PL) family 26 along with hypothetical proteins derived from various organisms. In this study, we determined the crystal structure of PcRGLX as the first structure of a member of this family. Based on the substrate-binding orientation and substrate specificity, PcRGLX is an exo-type PL that cleaves rhamnogalacturonan from the reducing end. Analysis of PcRGLX-complex structures with reaction products indicate that the active site possesses an L-shaped cleft that can accommodate galactosyl side chains, suggesting side-chain-bypassing activity in PcRGLX. Furthermore, we determined the residues critical for catalysis by analyzing the enzyme activities of inactive variants.

Keywords: crystal structure; exo-rhamnogalacturonan lyase; polysaccharide lyase family 26.

Publication types

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

MeSH terms

  • Catalysis
  • Crystallography, X-Ray
  • Fungal Proteins / chemistry*
  • Pectins / chemistry*
  • Penicillium chrysogenum / enzymology*
  • Polysaccharide-Lyases / chemistry*
  • Structure-Activity Relationship

Substances

  • Fungal Proteins
  • Pectins
  • Polysaccharide-Lyases

Associated data

  • PDB/5XQ3
  • PDB/5XQG
  • PDB/5XQJ
  • PDB/5XQO
  • PDB/5KBP
  • PDB/5OLR