Gram Stain 

          Leuconostoc mesenteroides are gram positive.  This means that when you stain it, the result is a purple color.  The Gram is a reflection of the differences in the biochemical and structural properties of the bacteria.  When you have a slide that contains a heat fixed spread of the bacterial cells that has been coated/ died in a stain, the result of all this is that the bacterial cells turn a violet purple color.

This shows what a gram positive stain looks like.