title: A new bi-modular endo-β-1,4-xylanase KRICT PX-3 from whole genome sequence of Paenibacillus terrae HPL-003.
abstract: A new bi-modular, wide pH spectrum and highly active xylanase KRICT PX3 (JF320814) isolated from Paenibacillus terrae HPL-003 (KCTC11987BP) has been cloned and expressed in Escherichia coli. Purified recombinant xylanase KRICT PX-3 (1,620 bp, 540aa, NCBI accession number JF320814) showed highly active at 55°C in pH 4.0-11.0, and stability for at least 24h at 50°C, and exhibited Km and Vmax of 0.2mg/mL and 153.8 U/mg on birchwood xylan. Most common ions did not affect the enzyme activity at 1mM concentration. This enzyme could belong to glycoside hydrolase family 10 because hydrolyzed glucuronoxylan and arabinoxylan substrate to xylobiose, xylotriose, and some traces of xylose as hydrolysis products. Model 3-D structure was composed of two domains, the catalytic domain of a (β/α)8 barrel fold while the small domain probably functions as a xylan binding domain, and the two domains are connected by a flexible linker peptide (PPLAIEKDIPSL). However, sequence alignment between xylan-binding module in this xylanase KRICT PX3 and CBM22 showed 21% of identity and 35% of similarity. This xylanase structure showed a distinctive group of enzyme cluster separately from the rest of GH10 xylanases, and seems to constitute a new type of xylanases.
authors.affiliation: Biorefinery Research Group, Green Chemistry Division, Korea Research Institute of Chemical Technology, Yusoeong P.O. Box 107, Daejon 305-600, Republic of Korea.
authors.forename: Ha Young
authors.initials: HY
authors.lastname: Song
authors.forename: Hee Kyung
authors.initials: HK
authors.lastname: Lim
authors.forename: Dal Rye
authors.initials: DR
authors.lastname: Kim
authors.forename: Kee In
authors.initials: KI
authors.lastname: Lee
authors.forename: In Taek
authors.initials: IT
authors.lastname: Hwang
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004795:Enzyme Stability; D016680:Genome, Bacterial; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D056507:Paenibacillus / Q000201:enzymology* / Q000235:genetics*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D011994:Recombinant Proteins; D043364:Endo-1,4-beta Xylanases
keywords: Multi-domain; Paenibacillus terrae; Xylan binding domain; Xylanase