第95回日本細菌学会総会

講演情報

オンデマンド口頭発表

[ODP13] 3. 生理・構造-d. 菌体表層構造・膜構造・細胞骨格

[ODP-063] 非結核性抗酸菌の形態に影響する糖ペプチド脂質抗原の発現と宿主応答機序

藤原 永年1,中 崇1,綾田 稔2,宮本 友司3,山本 三郎4,前田 伸司5 (1帝塚山大・現代生活学部・食物栄養学科,2大阪市立大・院医・ウイルス学,3国立感染症研究所ハンセン病研究センター,4日本BCG研究所,5北海道科学大・薬・薬学科)


MAC (Mycobacterium avium-intracellulare complex) is one of the major nontuberculous bacteria, and is classified into 28 serotypes by the serotype-specific glycopeptidolipid (GPL). We have reported the presence of core GPL in M. smegmatis and M. abscessus, and found the deletion of GPL in some strains. The colony morphology of the GPL-deleted strains changed rough-type instead of smooth-type, and implies to affect their virulence and pathogenicity.In this study, we showed the features of a clinical isolate, M. intracellulare Ku11 which produced a novel GPL. Its oligosaccharide 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. We analyzed the gene cluster involved in the GPL biosynthesis, and found the similarity of the deduced amino acid sequences in the eight open reading frames (orfs). We introduced the orf1, 6, 8 into M. intracelullare NF113 which produces serotype-1 GPL. We also deleted the orf8 in the Ku11 genome by CRISPR-Cas9 system. The orf1, 6, 8 were functionally responsible for the elongation of oligosaccharide, as a glycosyltransferase. Futhermore, we found that the intact Ku11-GPL was acetylated in some positions of oligosaccharide, and was recognized via TLR2. This result indicates that acetylation of GPL plays critical roles in host recognition. We discuss the structural and functional diversity of GPLs.