What is the optimal combination for crude lysis in DNA extraction?

The optimal combination for crude lysis in DNA extraction involves using detergent along with proteinase K. Detergents are effective at breaking down cell membranes, which is crucial for lysing the cells and releasing the DNA contained within them. The addition of proteinase K, an enzyme that digests proteins, further aids in the lysis process by breaking down histones and other proteins that may be associated with DNA. This combination maximizes the yield and purity of DNA, making it suitable for subsequent analysis.

Detergent alone might disrupt cell membranes but would not sufficiently degrade the proteins that could still inhibit the DNA analysis. Using alcohol with proteinase K does not adequately help in lysis, as alcohols are typically used in later steps of DNA extraction for precipitating DNA, rather than in the initial lysis stage. Using acid with detergent could cause denaturation of DNA and proteins, potentially leading to degradation of the DNA rather than effective extraction, making it an ineffective method for this purpose. Therefore, the combination of detergent and proteinase K is indeed the best choice for optimizing crude lysis in DNA extraction.