TLC and GC analyses of individual GPL bands (α, β, γ, γ2, γ3, δ) of wt M. avium 920A6, confirms the role of rtfA in ssGPL biosynthesis. GPL from 920A6 SmO was resolved by preparative TLC and individually resolved by analytical TLC. Each band was collected from the plate, and the lipids analyzed by GC/MS. Bands α represented serovar-8 specific GPL, bands β, γ (mix of γ2, γ3), and δ represented nsGPLs. GPL from the ΔrtfA mutant, 213R.4 was analyzed similarly and yielded identical nsGPL (data not shown).