Chloramphenicol Acetyl Transferase Assay

The chloramphenicol acetyltransferase (cat) gene, isolated from transposon Tn9 of Escherichia coli (1 ), is a convenient genetic marker for studies of transformation. (For a detailed description of the CAT gene, see Chapter 1 .) In plants, the CAT system is generally used in transient, rather than in stable, gene expression studies. Gene products are detected by assaying crude protein extracts of putatively transformed cells, usually within a few hours of transformation.