Three-dimensional structures pectate lyase

Lietzke, S.E., Yoder, M.D., Keen, N.T. and Jurnak, F. (1994) The three-dimensional structure of pectate lyase E, a plant virulence factor from Erwinia chrysanthemi. Plant Physiol Q6, 849-862. 

Functional Implications of the Three-Dimensional Structures of Pectate Lyases... 

Lietzke, S. E., Scavetta, R. D., Yoder, M. D., andjumak, F. (1996). The refined three-dimensional structure of pectate lyase E from Enuinia chrysanthemi at 2.2 A resolution. Plant Physiol. Ill, 73-92. 

Figure 13-3 The three-dimensional structure of pectate lyase C showing locations of amino acids substituted by oligonucleotide-directed mutation of the cloned gene.

As with glycoside hydrolases, the polysaccharide lyases (PL) have long been classified into sequence-related protein families (129) in the CAZy database (28). Presently, more than 20 PL families are listed in CAZy, and, because of significant recent attention, at least one three-dimensional structural representative is known for approximately one half of these (reviewed in Refe. (126,127), and (130) see also http //www.cazy.org/fam/acc PL.html). Not surprisingly, these endo-acting enzymes possess cleft-shaped active sites (126), akin to the polysaccharide erac/o-glycosidases vide supra). Characteristically, polysaccharide lyases bind their polyanionic substrates through basic amino acid residues and/or Ca++ ion complexation. Indeed, the activity of nearly all known pectate lyases strictly requires Ca++, which in some cases may directly affect the catalysis (126). 

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