Characterization of endo-beta-N-acetylglucosaminidase from alkaliphilic Bacillus halodurans C-125.
The genome sequencing project on alkaliphilic Bacillus halodurans C-125 revealed a putative endo-beta-N-acetylglucosaminidase (Endo-BH), which consists of a signal peptide of 24 amino acids, a catalytic region of 634 amino acids exhibiting 50.1% identity with the endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (Endo-A), and a C-terminal tail of 220 amino acids. Transformed Escherichia coli cells carrying the Endo-BH gene exhibited endo-beta-N-acetylglucosaminidase activity. Recombinant Endo-BH hydrolyzed high-mannose type oligosaccharides and hybrid type oligosaccharides, and showed transglycosylation activity. On deletion of 219 C-terminal amino acid residues of Endo-BH, the wild type level of activity was retained, whereas with deletions of the Endo-A homolog domain, the proteins were expressed as inclusion bodies and these activities were reduced. These results suggest that the enzymatic properties of Endo-BH are similar to those of Endo-A, and that the C-terminal tail does not affect the enzyme activity. Although the C-terminal tail region is not essential for enzyme activity, the sequence is also conserved among endo-beta-N-acetylglucosaminidases of various origins.
Fujita
Kiyotaka
K
Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
Takami
Hideto
H
Yamamoto
Kenji
K
Takegawa
Kaoru
K
D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology* / Q000235:genetics; D020134:Catalytic Domain / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000378:metabolism; D006031:Glycosylation; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase