NEW PYRUVYLATED, GLYCOSYLATED ACYLTREHALOSES FROM MYCOBACTERIUM-SMEGMATIS STRAINS, AND THEIR IMPLICATIONS FOR PHAGE RESISTANCE IN MYCOBACTERIA

Phage resistance and apparent lysogenization of Mycobacterium smegmati s due to infection with mycobacteriophage D29 results in the emergence of new variations of the pyruvylated, acylated trehaloses described b y Saadat and Ballou, J. Biol. Chem. 258 (1983) 1813-1818. Thin-layer c hromatography of the glycolipids from two strains of phage-resistant M . smegmatis (mc(2)22 and mc(2)11) and comparison with those from phage -sensitive strains revealed a new, more mobile glycolipid in each case . The structures of these acyltrehalose-containing lipooligosaccharide s were elucidated by a combination of gas-liquid chromatography-mass s pectrometry, methylation analysis, H-1 and C-13 NMR spectroscopy, and fast-atom bombardment mass spectrometry. The glycolipid from M. smegma tis mc(2)22 is beta-D-glcp-(1 --> 4,6-O-(1-methoxycarbonylethylidene)- beta-D-Glcp-(1 --> 4)-beta-D-Glcp-(1 --> 6)-2-O-acyl-(alpha-D-Glcp-(1 <-> 1)-3,4-di-O-acyl-alpha-D-Glcp and that from M. smegmatis mc(2)11 i s 4,6-O-(1-methoxycarbonylethylidene)-3-O-Me-beta -D-Glcp-(1 --> 3)-4, 6-0-(1-methoxycarbonylethylidene)-beta -D-Glcp-(1 --> 4)-P-DGlcp-(1 -- >, 6)-2-O-acyl-alpha-D-Glcp-(1 <-> 1)-3,4-di-O-acyl-alpha-D-Glcp. Thes e differ from the original pyruvylated glycolipids of Saadat and Ballo u in the extent of their O-acylation and O-methylation. The findings a re the first example of the definition of a chemical basis for phage r esistance and presumed lysogeny in mycobacteria, and show parallels to related changes in gram-negative enteric bacteria.