The Ladderman Labeling Kit is a novel random primer labeling system that takes advantage of longer primers and a thermostable DNA polymerase isolated from Bacillus caldotenax YT-G (Bca DNA polymerase). Unlike the E. coli Klenow fragment or modified T7 DNA polymerase, thermostable Bca DNA polymerase allows stable polymerization through templates with high GC content (highly structured regions). The longer 9-mer primers increase the efficiency of incorporation of labeled nucleotides up to 80%.
With this kit, random priming is accomplished within 10 minutes to create efficiently-labeled DNA probes. The kit is designed for use with [32P]-alpha-, [35S]-alpha-, or [3H]-alpha-dCTP labels, but it can also be used with biotin, digoxigenin or DNP-labeled dUTPs by replacement of the dNTP mixture. Generally, a probe with specific activity of >109 dpm/mg DNA will be obtained with [32P]-alpha-dCTP (approx. 3,000 Ci/mmol, 111 TBq/mmol).
