Format

Send to

Choose Destination
J Biol Chem. 2000 Jan 21;275(3):2009-18.

Biochemical analysis of recombinant fungal mutanases. A new family of alpha1,3-glucanases with novel carbohydrate-binding domains.

Author information

1
Novo Nordisk A/S, Bagsvaerd DK-2880, Denmark. ccf@novo.dk

Abstract

Nucleotide sequence analysis shows that Trichoderma harzianum and Penicillium purpurogenum alpha1,3-glucanases (mutanases) have homologous primary structures (53% amino acid sequence identity), and are composed of two distinct domains: a NH(2)-terminal catalytic domain and a putative COOH-terminal polysaccharide-binding domain separated by a O-glycosylated Pro-Ser-Thr-rich linker peptide. Each mutanase was expressed in Aspergillus oryzae host under the transcriptional control of a strong alpha-amylase gene promoter. The purified recombinant mutanases show a pH optimum in the range from pH 3.5 to 4.5 and a temperature optimum around 50-55 degrees C at pH 5.5. Also, they exhibit strong binding to insoluble mutan with K(D) around 0.11 and 0.13 microM at pH 7 for the P. purpurogenum and T. harzianum mutanases, respectively. Partial hydrolysis showed that the COOH-terminal domain of the T. harzianum mutanase binds to mutan. The catalytic domains and the binding domains were assigned to a new family of glycoside hydrolases and to a new family of carbohydrate-binding domains, respectively.

PMID:
10636904
DOI:
10.1074/jbc.275.3.2009
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center