How to distinguish the substance is nutrition or growth hormon
Posted 28 September 2009 - 12:02 AM
Posted 28 September 2009 - 01:48 AM
well you could radiolable your substrate and feed it to the bug. if you find radioactive atoms being incoperated into the cells protein/wall etc then you know the compound is being used as nutritional substrate.
alternatively, you can try looking at the growth response of the bacterium. Ideally a hormone should give a growth response in small quantities (pM to nM range) while a nutritional substrate should continue giving a growth response in the uM to mM range. Although you could have a poor growth hormone, so a week response.
Posted 28 September 2009 - 02:18 AM
adding to what mr blue said, you could formulate medium in which the substance was the sole source of C or N. For the "hormone" - use highly dilute levels in medium that supports growth and note growth promotion v. control.