METHANOL DOES NOT SPECIFICALLY INHIBIT ENDOGENOUS BETA-GLUCURONIDASE (GUS) ACTIVITY

One of the problems associated with the use of the bacterial gus A gen e as a reporter is the presence of 'endogenous GUS' activity in some p lant species. A recent paper [1] suggests that the addition of methano l to GUS reaction buffer specifically inhibits endogenous GUS activity while enhancing the activity of an introduced gus A gene. The results described in this paper suggest this phenomenon may be explained by t he effect methanol has on cell membranes and demonstrate that it does not specifically inhibit endogenous GUS activity.