Trehalosamine

Nonreducing disaccharide trehalose is used as a stabilizer and humectant in various products and is a potential medicinal drug, showing curative effects on the animal models of various diseases. However, its use is limited as it is hydrolyzed by trehalase, a widely expressed enzyme in multiple organisms. Several trehalose analogs are prepared, including a microbial metabolite 4-trehalosamine, and their high biological stability is confirmed. For further analysis, 4-trehalosamine is selected as it shows high producibility. Compared with trehalose, 4-trehalosamine exhibits better or comparable protective activities and a high buffer capacity around the neutral pH. Another advantage of 4-trehalosamine is its chemical modifiability: simple reactions produce its various derivatives. Labeled probes and detergents are synthesized in one-pot reactions to exemplify the feasibility of their production, and their utility is confirmed for their respective applications. The labeled probes are used for mycobacterial staining. Although the derivative detergents can be effectively used in membrane protein research, long-chain detergents show 1000-3000-fold stronger autophagy-inducing activity in cultured cells than trehalose and are expected to become a drug lead and research reagent. These results indicate that 4-trehalosamine is a useful trehalose substitute for various purposes and a material to produce new useful derivative substances.

A general strategy for the diverse synthesis of ten disaccharide aminoglycosides, including natural 2-trehalosamine (1), 3-trehalosamine (2), 4-trehalosamine (3), and neotrehalosyl 3,3'-diamine (8) and synthetic aminoglycosides 4-7, 9, and 10, has been developed. The aminoglycoside compounds feature different anomeric configurations and numbers of amino groups. The key step for the synthesis was the glycosylation coupling of a stereodirecting donor with a configuration-stable TMS glycoside acceptor. Either the donor or acceptor could be substituted with an azido group. The aminoglycosides prepared in the present study were characterized by 1D and 2D NMR spectroscopy.

Bacillus amyloliquefaciens has been widely used as a probiotic in the field of biological control,and its antibacterial compounds plays an important role in the prevention and control of plant, livestock and poultry diseases. It has the advantages of green, safe and efficiency. This study aims to separate and purify active ingredient from Bacillus amyloliquefaciens GN59 and study its antibacterial activity. A novel compound was isolated from GN59 by column chromatography on silica gel and HPLC purification. The chemical structure was identified as α-D-glucopyranosyl-(1 → 1')-3'-amino-3'-deoxy-β-D-glucopyranoside (a,β-3-trehalosamine) on the basis of spectroscopic analysis. This is the first report about a,β-3-trehalosamine isolated from biological resources on an antibiotic activity against pathogenic bacterium. The 3'-neotrehalosamine displayed antibacterial activity across a broad spectrum of microorganisms, including different gram-positive and gram-negative bacteria, with minimal inhibitory concentration (MIC) values ranging from 0.5 to 0.7 mg/mL. The results indicated that the 3'-neotrehalosamine from GN59 might be a potential candidate for bactericide.