Premium
The Chemical Modification of the Essential Groups of β‐N‐Acetyl‐D‐glucosaminidase from Turbo cornutus Solander
Author(s) -
Lin JianCheng,
Chen QingXi,
Shi Yan,
Li ShaoWei,
Zhao Hong
Publication year - 2003
Publication title -
iubmb life
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.132
H-Index - 113
eISSN - 1521-6551
pISSN - 1521-6543
DOI - 10.1080/15216540310001626601
Subject(s) - tryptophan , chemical modification , enzyme , residue (chemistry) , chemistry , cysteine , serine , stereochemistry , lysine , active site , biochemistry , enzyme assay , amino acid
Abstract The chemical modification of β‐N‐acetyl‐D‐glucosaminidase (EC3.2.1.30) from Turbo cornutus Solander has been first studied. The results demonstrate that the sulfhydryl group of cysteine residues and the hydroxyl group of serine residues are not essential to the enzyme's function. The modification of indole group of tryptophan of the enzyme by N‐bromosuccinimide (NBS) can lead to the complete inactivation, accompanying the absorption decreasing at 278 nm and the fluorescence intensity quenching at 335 nm, indicating that tryptophan is essential residue to the enzyme. The modification of amino group of lysine residue by formaldehyde and trinitrobenzenesulfonic acid also inactivates the enzyme completely. The results show that lysine and tryptophan are probably situated in the active site of the enzyme. The modification of the imidazole residue and carboxyl group leads to inactivate incompletely, indicating they are not the composing groups of the enzyme active center, and they are essential for maintaining the enzyme's conformation which is necessary for the catalytic activity of the enzyme. IUBMB Life, 55: 547‐552, 2003