Polygalacturonases: Active site analyses and mechanism of action
نویسنده
چکیده
Polygalacturonases from various sources have been analyzed by ClustalW and T-COFFEE, for identification of conserved and functional motifs in them. All the 104 polygalacturonases analyzed by the above programs, revealed four highly conserved motifs, viz., NTD, G/QDD, G/SHG and RIK among them. Distance conservation between the motifs was also observed. Based on the available evidences from chemical modification studies on active site amino acids, site-directed mutagenesis, protein sequence analysis and X-ray crystallographic data, a mechanism of action is proposed for this group of enzymes.
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