Purification of histone deacetylase HD1-A of germinating maize embryos.

We have purified the soluble nuclear histone deacetylase HD1-A of germinating maize embryos. By a combination of 6 chromatographic steps we achieved a 77,000-fold purification of an enzymatically active protein. Gel filtration chromatography revealed a molecular weight of 45 kDa of the native enzyme and electrophoretic analysis of the purified enzyme by SDS-PAGE resulted in a single band at a molecular weight of 48 kDa, indicating that the enzyme is a monomer protein. When fractions with enzyme activity of different stages of chromatographic purification were subjected to isoelectric focusing, enzyme activity focused at a pH of around 6.4 as measured in an activity gel assay; second dimension SDS-PAGE again revealed a protein spot at a molecular weight of 48 kDa.