3.0.CO;2-I/asset/equation/tex2gif-ueqn-1.gif?v=1&t=h5n48gu1&s=67a49e13301ecee3c2a3d4aac848aae356f0b41d" class="inlineGraphic">[HgGe9]2−—A Polymer with Zintl Ions as Building Blocks Covalently Linked by Heteroatoms

✍ Scribed by Anke Nienhaus; Ralf Hauptmann; Thomas F. Fässler

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 121 KB
• Volume: 41
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/1521-3773(20020902)41:17<3213::aid-anie3213>3.0.co;2-i

✦ Synopsis

We have provided strong evidence that the GGGX motif described for some lipases not only plays a role in stabilizing the tetrahedral intermediate during catalysis, but also governs activity towards TAs. With the exception of GCL, all tested esterases and lipases bearing the GGGX motif hydrolyzed the model acetates. In the case of GCL, we assume that this lipase will accept other TAEs.

The overall amino acid sequence similarity between these hydrolases originating from bacteria, yeast, and mammalian sources is rather low and only small regions around the GGGX motif and the active serine residue are conserved. This structure dissimilarity is also reflected by the large differences between the substrates normally accepted by these hydrolases, [15] which means, in turn, that knowledge about their usual biocatalytic activity would not suggest that these enzymes would have activity towards TAs in common.

Furthermore, our computer model also allows the prediction of mutants with enhanced or even inverse stereoselectivity in the resolution of the model acetates of TAs. [16] Experimental Section

All experimental details can be found in the Supporting Information.