Single-strand DNA-binding protein (SSB) binds to single-stranded DNA (ssDNA) molecules or a single-stranded region of a double strand-DNA in a biological process such as DNA replication, recombination, or repair. For example, DNA helicase unwinds double-strand DNA to form single-strand DNA. E. coli SSB forms homotetramer; each subunit has a molecular weight of 19 kDa.  The Gel Shift Single-strand DNA Binding Assay is designed for analysis of SSB DNA-binding activity using a conventional acrylamide electrophoresis. The SSB DNA-binding activity is visualized by the DNA band shift. The SSB-bound DNA migrates slower than the free DNA.

The Gel Shift Single-strand DNA Binding Assay Kit (Catalog No. GSSB100K) includes 150 µl of 10 x Buffer, 150 µl of 10 x ssDNA (a 45-mer single-strand DNA) and 100 µl of 4 x gel loading buffer.

The Gel Shift Single-strand DNA Binding Assay Kit Plus (Catalog No. GSSB100KE) includes 150 µl of 10 x Buffer, 150 µl of 10 x ssDNA, 150 µl of 2 mg/ml E. coli single-strand DNA binding protein SSB and 100 µl of 4 x gel loading buffer.