Biomedical subjects

Johann Grognux

Publications and source records attributed to Johann Grognux.

2 recordsLinked to original sources

PubMed2006

A red-fluorescent substrate microarray for lipase fingerprinting.

A lipase substrate microarray was obtained by printing aliphatic C2-C12 monoesters of (5R)- and (5S)-3-(5,6-dihydroxyhexyloxy)benzaldehyde by reductive alkylation on amine-functionalized glass slides coated with bovine serum albumin and a short PEG linker. The microarray features 12 substrates and their 66 possible binary mixtures spotted in a 9 x 36 spot array. Lipase reactions are detected by chemoselective NaIO(4)-oxidation of the 1,2-diol hydrolysis product to form an aldehyde, which is then tagged with the red-fluorescent dye rhodamine B sulfohydrazide . Specific fingerprints are produced by active enzymes. These experiments provide the first example of lipase fingerprinting using microarrays.

Cluster Analysis↗

PubMed2004

Classifying enzymes from selectivity fingerprints.

Fingerprints of lipases and esterases have been recorded by using an array of chiral fluorogenic aliphatic esters of increasing chain length (C(4)-C(16)). Classification of the enzyme series was carried out with selectivity data by clustering and principal component analysis (PCA). Enzymes were classified on the basis of selectivity for chain length (C(4)-C(6) vs. C(10)-C(16)) and of middle-chain-length (C(8)-C(10)) reactivity. A minimum set of nine substrates was defined by cluster analysis of relative reactivities of each substrate for the different enzymes. This selectivity-based analysis is general. It does not require a common reference substrate to react with all enzymes or vice versa, and is independent of knowing the exact concentration of active protein in the enzyme samples.

Cluster Analysis↗