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.

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

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.