title: Presence of N-L-lactyl-D-perosamine residue in the sheath-forming polysaccharide of Thiothrix fructosivorans.
abstract: Thiothrix fructosivorans forms a microtube (sheath) that encloses a line of cells. This sheath is an assemblage of [→4)-GlcN-(1→4)-Glc-(1→]n with side chains of Rha4N-(1→3)-Fuc(1→ at position 3 of Glc. The sheath-forming polysaccharide (SFP) may have some substitutions but this is not yet confirmed. To investigate the possible substitutions, the sheath was prepared by mild treatments. Solid-state NMR analysis suggested the presence of N-substitution. The sheath was hydrolyzed with concentrated HCl at 0°C, followed by derivatization with 4-aminobenzoic acid ethyl ester (ABEE). The presence of N-lactyl-Rha4N-Fuc-ABEE was suggested by NMR spectroscopy. Lactic acid was determined to be the l-isomer by chiral HPLC analysis. To estimate the N-lactylation degree, the sheath was N-acetylated. N-Acetyl-Rha4N-Fuc-ABEE and N-lactyl-Rha4N-Fuc-ABEE were then collectively recovered, and their abundance ratio was determined to be 1:4 by NMR analysis. When hydrolysis was performed at 40°C, GlcNAc-ABEE was obtained. For estimation of the N-acetylation degree, the sheath was N-acetylated with deuterated acetic anhydride and then N-acetyl-GlcN-ABEE was prepared. The content of deuterated N-acetyl-GlcN-ABEE was determined to be 50% based on the relative intensity of the acetyl proton signal in the 1D-(1)H NMR spectrum. It was concluded that Rha4N is mostly N-l-lactylated and GlcN is substoichiometrically N-acetylated.
authors.affiliation: Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Kawasaki
authors.affiliation: Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Kondo
authors.affiliation: Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Narizuka
authors.affiliation: Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Endo
authors.affiliation: Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan; CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Katahira
authors.affiliation: Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan.
authors.forename: Izuru
authors.initials: I
authors.lastname: Kawamura
authors.affiliation: School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama, Kawasaki 214-8571, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Sato
authors.affiliation: Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan. Electronic address: mtake@ynu.ac.jp.
authors.forename: Minoru
authors.initials: M
authors.lastname: Takeda
mesh_terms: D002851:Chromatography, High Pressure Liquid; D019344:Lactic Acid / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008358:Mannose / Q000031:analogs & derivatives* / Q000737:chemistry; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D053525:Thiothrix / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D011135:Polysaccharides, Bacterial; C057033:4-amino-4,6-dideoxy-D-mannose; D019344:Lactic Acid; D008358:Mannose
keywords: N-Lactylation; Perosamine; Polysaccharide; Sheath; Thiothrix fructosivorans