Methods and kits for nucleic acid sample preparation for sequencing

A method for DNA library construction, comprising:

• modifying DNA fragments with a polymerase and a polynucleotide kinase in a first reaction mixture sufficient for end repair of the DNA fragments;
• contacting the end repaired DNA fragments with a (3′→5′ exo-) polymerase in a second reaction mixture sufficient for A-tailing the end-repaired DNA fragments;
• ligating DNA adaptors to the A-tailed DNA fragments in a third reaction mixture comprising a nucleic acid ligase;
• wherein one or more of the first reaction mixture, the second reaction mixture, and the third reaction mixture are rehydrated from a lyophilized form in a reaction volume comprising the DNA fragments.

A method of for DNA library construction, comprising:

• modifying DNA fragments with T4 DNA polymerase and T4 polynucleotide kinase in a first reaction mixture sufficient for end repair of the DNA fragments;
• contacting the end repaired DNA fragments with Klenow (3′→5′ exo-) in a second reaction mixture sufficient for A-tailing the end-repaired DNA fragments;
• ligating DNA adaptors to the A-tailed DNA in a third reaction mixture comprising T4 DNA ligase,
• wherein one or more of the first reaction mixture, the second reaction mixture, and the third reaction mixture are rehydrated from a lyophilized form in a reaction volume comprising the DNA fragments.