ZymoBIOMICS Microbial Community DNA Standard II (Log Distribution) is a mixture of genomic DNA of eight bacterial and two fungal strains. The microbial standard is accurately characterized and contains negligible impurity (< 0.01%). It was constructed by pooling DNA extracted from pure cultures of the ten microbial strains. The DNA from each pure culture was quantified before pooling. After mixing, the microbial composition was confirmed using NGS-based sequencing. This microbial standard can be used to assess the performance of microbiomics workflows and can also be used as a positive control for the routine QC purpose. Theoretical Composition Based on Genomic DNA: Listeria monocytogenes – 89.1%, Pseudomonas aeruginosa – 8.9%, Bacillus subtilis – 0.89%, Saccharomyces cerevisiae – 0.89%, Escherichia coli – 0.089%, Salmonella enterica – 0.089%, Lactobacillus fermentum – 0.0089%, Enterococcus faecalis – 0.00089%, Cryptococcus neoformans – 0.00089%, and Staphylococcus aureus – 0.000089%.