Use of horseradish peroxidase- and @entity941 -modified XXXX derivatives for simultaneous labeling of nucleic acids and proteins.

@entity1522 @entity1568 @entity2036 @entity900 @entity941 @entity599
BACKGROUND: Microarray platforms will change immunochemical and nucleic acid-based analysis of cell homogenates and body fluids compared with classic analyses. Microarrays use labeled target and immobilized probes, rather than fixed targets and labeled probes. We describe a method for simultaneous labeling of nucleic acids and proteins. METHODS: Horseradish peroxidase- and @entity941 -modified @entity900 derivatives were used for labeling of nucleic acids and proteins. These reagents, called the Universal Linkage System (ULS), bind to @entity599 - and @entity1568 -donor ligands present in @entity1522 and @entity2036 . For automated screening of proteins and nucleic acids on microarrays, it is advantageous to label these biomolecules without pre- or postpurification procedures. The labeling of antibodies and nucleic acids in whole serum was therefore pursued. RESULTS: Immunoglobulins in nonpurified serum were labeled efficiently enough to be used for immunochemistry. To investigate whether protein-adapted labeling allowed nucleic acid labeling as well, 1 microg of plasmid DNA was added to 1 microL of serum. DNA and serum proteins were simultaneously labeled, and this labeled DNA could be used as a probe for direct fluorescence in situ hybridization. CONCLUSION: ULS provides a direct labeling tool for the (simultaneous) modification of proteins and nucleic acids even in unpurified samples.
