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Amount of positive control for bisulfite treatment - (Dec/11/2009 )

Hello everybody,

I am using EZ DNA Methylation-Gold Kit for bisulfite treatment of plant DNA. I plan to use 'Universal Methylated DNA Standard and control primers' from Zymo research in conjunction with it as a positive control. I understand that a minimum of 500 pg of DNA is required for bisulfite conversion. However, the concentration of Universal Methylated DNA Standard indicated on the tube containing the DNA provided is 100pg/20uL (5pg/uL). But it is also mentioned that there is 5ug/20uL of salmon sperm DNA as a carrier. I am confused as to how much of standard control DNA would be required for treatment. :D

Any suggestion would be greatly appreciated. Hope to hear from somebody soon :D


So the concentration (5 pg/ul) is the already modified DNA. If you want to know how much DNA should be used for treatment, ideally you can use about 1 ug DNA for treatment. Because there is significant DNA loss during treatment and purification, the recovered DNA from 1 ug starting DNA after treatment would be at picogram scale. I guess that is why the standard modified DNA provided in the kit has such low concentration.