STRUCTURE OF A NOVEL PHOSPHOCHOLINE-CONTAINING GLYCOGLYCEROLIPID FROMMYCOPLASMA-FERMENTANS

Mycoplasma fermentans is thought to be a pathogen of rheumatoid arthri tis or cofactor of AIDS. A novel phosphocholine-containing glycoglycer ophospholipid named GGPL-I was isolated from a M. fermentans infected human helper T-cell culture. It was revealed that GGPL-I is a lipid co mponent of the M. fermentans and a major immunological determinant. Th e GGPL-I was purified by DEAE-Sephadex column chromatography and repea ted Iatrobeads column chromatography. The purified glycophospholipid w as subjected to structural characterization by thin-layer chromatograp hy, Fourier-transform infrared spectrometry, liquid secondary ion mass spectrometry, and nuclear magnetic resonance spectroscopy. Its struct ure was determined to be as follows: lpha-glucopyranosyl-(1'-3)-1,2-di acyl-sn-glycerol. This glycoglycerophospholipid is unique in containin g phosphocholine, which is attached to C-6 of glucose. The stereospeci fic numbering (an) of naturally occurring GGPL-I was determined throug h comparison with chemically synthesized compounds.