PUL ID

PUL0577

PubMed

21098515, Glycobiology. 2011 Apr;21(4):503-11. doi: 10.1093/glycob/cwq191. Epub 2010 Nov 22.

Characterization method

SDS-PAGE,enzyme activity assay

Genomic accession number

NC_006370.1

Nucelotide position range

541673-560134

Substrate

chitin,chitobiose,cellobiose

Loci

PBPRA0516-PBPRA0526

Species

Photobacterium profundum/74109

Degradation or Biosynthesis

degradation

Cluster number

1

Gene name

Gene position

Gene type

Found by CGCFinder?

- 1 - 1413 (-) CDS No
- 1478 - 3883 (-) CAZyme: GH94 Yes
- 3923 - 5854 (-) CAZyme: GH20 Yes
- 5864 - 6751 (-) other Yes
- 6744 - 8480 (-) CAZyme: GH9 Yes
- 8522 - 9517 (-) TC: gnl|TC-DB|Q97UG5|3.A.1.5.8 Yes
- 9546 - 10517 (-) TC: gnl|TC-DB|Q9X271|3.A.1.5.15 Yes
- 10517 - 11545 (-) TC: gnl|TC-DB|Q8U1J6|3.A.1.5.6 Yes
- 11548 - 12534 (-) TC: gnl|TC-DB|Q8U1J7|3.A.1.5.6 Yes
- 12676 - 14355 (-) TC: gnl|TC-DB|Q8U1J8|3.A.1.5.6 Yes
- 15109 - 18462 (-) STP: STP|dCache_1,STP|HisKA,STP|HATPase_c,STP|Response_reg,STP|PAS No

PUL ID

PUL0577

PubMed

21098515, Glycobiology. 2011 Apr;21(4):503-11. doi: 10.1093/glycob/cwq191. Epub 2010 Nov 22.

Title

Elucidation of exo-beta-D-glucosaminidase activity of a family 9 glycoside hydrolase (PBPRA0520) from Photobacterium profundum SS9.

Author

Honda Y, Shimaya N, Ishisaki K, Ebihara M, Taniguchi H

Abstract

A glycoside hydrolase (GH) gene from Photobacterium profundum SS9 (PBPRA0520) belonging to GH family 9 was expressed in Escherichia coli. The protein was expressed with the intact N-terminal sequence, suggesting that it is an intracellular enzyme. The recombinant protein showed hydrolytic activity toward chitobiose [(GlcN)(2)] and cellobiose (CG(2)) in various disaccharides. This protein also released 4-nitrophenol (PNP) from both 4-nitrophenyl-beta-D-glucosaminide (GlcN-PNP) and 4-nitrophenyl-beta-D-glucoside (Glc-PNP). The hydrolytic pattern observed in chitooligosaccharides and cellooligosaccharides suggested that the reaction proceeded from the nonreducing end in an exo-type manner. Time-dependent (1)H-nuclear magnetic resonance (NMR) analysis of the anomeric form of the enzymatic reaction products indicated that the protein is an inverting enzyme. k(cat)/K(m) of (GlcN)(2) hydrolysis was 14 times greater than that of CG(2) hydrolysis. These results suggested that the protein is an exo-beta-D-glucosaminidase (EC 3.2.1.165) rather than a glucan 1,4-beta-D-glucosidase (EC 3.2.1.74). Based on the results, we suggest that the function of conserved GH9 proteins in the chitin catabolic operon is to cleave a (GlcN)(2)-phosphate derivative by hydrolysis during intracellular chitooligosaccharide catabolism in Vibrionaceae.