[ODP3A] a. Cell Surface Structure, Membrane Structure, and Cytoskeleton

[ODP-029] Identification of glycopeptidolipid biosynthesis gene cluster from clinical M. intracellulare strain

○Nagatoshi Fujiwara¹, Shin Nakaya², Yuji Miyamoto³, Minoru Ayata⁴, Takashi Naka¹, Shinji Maeda⁵ (¹Tezukayama Univ., ²Otemae College of Nutrition, Dept Nutrition, ³Leprosy Research Center, National Institute of Infectious Diseases, ⁴Osaka City Univ. Grad. Sch. Medicine, Dept. Virology, ⁵Hokkaido Univ. of Science, Fac. Pharmacy)

MAC (Mycobacterium avium-intracellulare complex) is classifiable into 28 serotypes based on the serotype-specific glycopeptidolipid (GPL) antigen. Mycobacterium intracellulare Ku11 strain was isolated from a patient in Kumamoto. The Ku11 strain produced a novel GPL. The oligosaccharide moiety was defined as α-Rha-(1→3)-2-O-Me-α-Rha-(1→3)-α-Rha-(1→3)-α-Rha-(1→3)-α-Rha-(1→2)-6-d-α-Tal. The Ku11-GPL was composed of 6 pieces of non-acylated sugars. We are now trying to clarify the characterization of the gene cluster involved in GPL biosynthesis. We checked the similarity of the deduced amino acid sequences in the open reading frames (orfs), and tried to introduce orf6, 8, 16 into the same species, M. intracelullare NF113 strain which produce serotype 1-GPL. The sugar moiety of GPL was elongated, and the structure of sugar moiety was identified by ESI/MS/MS. As the results, we identified the orf6, 8, 16 that is functionally responsible for the elongation of oligosaccharide, glycosyltransferase. Now, it is possible to reconstruct 5 pieces of sugar in Ku11-GPL by introduction of orf6, 8, 16 into NF113 strain. We technically established the method of introduction of GPL biosynthesis orfs into M. intracelullare and structural identification by ESI/MS/MS. To clarify the complete biosynthesis genes of the Ku11-GPL, we discuss the structural and functional diversity of GPLs.