Southern enzyme assay

The products of gene expression (mRNA and proteins) can be measured by techniques such as the following. Northern blots are very similar to Southern blots except that the original sample contains a mixture of mRNA molecules that are separated by electrophoresis, then hybridized to a radioactive probe. Microarrays are used to determine the differing patterns of gene expression in two different types of cells—for example, normal and cancer cells. Enzyme-linked immunosorbent assays (ELISAs) and western blots (immunoblots) are used to detect specific proteins. 

In Vitro Studies. An assay for measuring taurine N-acyltransferase activity with C-phonylacetyl CoA as substrate has boon described (79). Enzyme activity was located In the matrix of the mitochondrion and was usually higher In kidney than liver for the nine fish species studied. Studies with Isolated renal tubules from the winter flounder and the southern flounder (84 and James and Pritchard, unpublished) have shown that added phenylacetlc acid and benzoic acid were extensively metabolized to their taurine conjugates during a 60 minute Incubation. 

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