Protease Screen

Four additional commercial proteases were examined for the hydrolysis of (R,S)-4 including three variants of Bacillus lentus proteases engineered for stability (Tab. 2). Of these Bacillus lentus protease-I gave equivalent selectivity to that of Ba- 

Reaction conditions room temperature, 10% substrate loading, 0.3 M phosphate buffer with pH=7.0. a) I, II, and III represent proteases from different commercial sources. 

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Caspase 1 (Table 1, entry 4) Another protease screened using fragments is caspase 1. Using a tethering approach (described earlier) active sub-site binders were identified and then linked to produce a sub-micromolar inhibitor 24. Further optimisation by rigidifying the linker produced a ligand-efficient nanomolar inhibitor 25 [38]. 

Urbina HD, Debaene F, Jost B, Bole-Feysot C, Mason DE, Kuzmic P, Harris JL, Winssinger N. Self-assembled small-molecule microarrays for protease screening and profihng. Chem-BioChem. 2006 7 1790-1797. 

There are many applications for microarray SPR, which will generally also hold for other types of microarrays to name just a few these are as follows screening for ligands in drug discovery, screening for enzyme substrates, for example, kinases and proteases, screening for biomarkers in diagnostics and other clinical applications and the study of protein networks. 

Proteases are hydrolytic enzymes with important application in industries, in particular, in detergent and in the food industry. A metagenomic study in which 100 000 plasmid clones were screened for proteolytic activity found one positive done, which was determined to be novel by sequencing analysis [84]. 

Cathepsin D. The design of inhibitors of the aspartyl protease cathepsin D started from a virtual library of peptide analogs that contained the typical hydroxyethylamine isoster for the cleavable peptide bond. As the availability of starting materials would have generated a library of about 1 billion compounds, virtual screening was applied to reduce this multitude of candidate structures to a reasonable number. The backbone of a peptide... 

Figure 16.5 Protease inhibitors from virtual screening.

Desai PV, Patny A, Sabnis Y, Tekwani B, Gut J, Rosenthal P, Srivastava A, Avery M. Identification of novel parasitic cysteine protease inhibitors using virtual screening. 1. The ChemBridge database. / Med Chem 2004 47 6609-15. 

The identification of non-peptidic lead structures remains a challenge. Screening of natural product extracts led to the identification of two po-lyhydroxylated biphenyls ((10a) and (10b), Figure 2.13) that show submicromolar inhibition of the viral protease [156]. A recent report discloses polyesters of glucose (11) and gallic acid (12) as micromolar inhibitors of the NS3 protease [157]. 

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