Glycine Residues Provide Flexibility for Enzyme Active Sites

Glycine residues provide flexibility for enzyme active sites.

The high resolution refined structures of 23 enzymes were analyzed to determine the properties of amino acids involved in active site regions. These regions were found to be rich in G-X-Y or Y-X-G oligopeptides, where X and Y are polar and non-polar residues, respectively, that are small and with low polarity. Other regions of the enzyme molecules have significantly fewer of these sequences. Th...

Flexibility analysis of enzyme active sites by crystallographic temperature factors.

Protein flexibility is inherent to protein structural behavior. Experimental evidence for protein flexibility is extensive both in solution and in the solid state. A major question is whether the flexibility observed in enzymes is simply an inherent property of proteins that must always be borne in mind or is essential for catalysis or substrate binding. The temperature factors or B-values, as ...

Mapping enzyme active sites in complex proteomes.

Genome sequencing projects have uncovered many novel enzymes and enzyme classes for which knowledge of active site structure and mechanism is limited. To facilitate mechanistic investigations of the numerous enzymes encoded by prokaryotic and eukaryotic genomes, new methods are needed to analyze enzyme function in samples of high biocomplexity. Here, we describe a general strategy for profiling...

Dispensations provide for flexibility in church law.

Role of aminoacidic residues inside active sites of metalloproteins

The role of the residues inside the active cavity of metalloproteins can be investigated by using the metal ion itself as a spectroscopic probe. For example in carbonic anhydrase the cobalt(I1) substituted enzyme has allowed us to understand the role of a free histidine hanging in the cavity in lowering the pK of the coordinated water. Substitution of zinc with cobalt(fi) in superoxide dismutas...