NMR SPECTRAL INVESTIGATIONS - PART 48 - H-1 AND C-13 NMR ASSIGNMENTS OF A LIPOPOLYSACCHARIDE OBTAINED FROM THE DEEP ROUGH MUTANT OF ESCHERICHIA-COLI-D31M4

The hexamethyl derivative of lipopolysaccharide (LPS), obtained by dia zomethane methylation of LPS extracted from a deep mutant of Escherich ia coli D31m4, followed by high-performance liquid chromatographic pur ification, was subjected to home-and heteronuclear two-dimensional NMR spectroscopy (DQF-COSY, HOHAHA, NOESY, HMQC and HMBC) to achieve H-1 and C-13 NMR assignments, particularly of the sugar backbone. These st udies confirmed two each of glucosamine (GlcN), 3-deoxy-D-manno-octulo sonic acid (Kdo), phosphate, beta-hydroxymyristate and beta-acyloxymyr istate and the structure of the tetrasaccharide as alpha-Kdo(p)-(2 --> 4)-alpha-Kdo(p)-(2 --> 6)-beta-D-Glc(p)N-(1 --> 6)alpha-D-Glc(p)N, bi sphosphorylated at the I and 4' positions. (C) 1998 John Wiley & Sons Ltd.