Glycolipid Trehalose Research Articles

An improved synthesis of 6- O--mycoloyl- and 6- O-corynomycoloyl-α,α-trehalose with observations on the permethylation analysis of trehalose glycolipids

An improved synthesis of 6- O--mycoloyl- and 6- O-corynomycoloyl-α,α-trehalose with observations on the permethylation analysis of trehalose glycolipids

Dicorynomycoloyl trehalose activity: Comparison of the activity of α,α′- and β,β′-trehalose derivatives on mitochondrial oxidative phosphorylation

6,6'-Dicorynomycoloyl esters of alpha,alpha'- or beta;beta'-trehalose were synthesized and tested on isolated rat liver mitochondria. In contrast to the well known site-II-specific uncoupling effect of the alpha,alpha'-trehalose derivative, the beta,beta'-trehalose derivative exhibited only non-specific inhibition of active respiration in the presence of glutamate. It is proposed that this unexpected difference between the two isomers could arise from conformational differences in the carbohydrate moiety of the glycolipids, which would render the beta,beta' isomer unable to recognize targets specific to the alpha,alpha'-trehalose glycolipid.

Identification of the physiologically active state of the mycobacterial glycolipid trehalose 6,6'-dimycolate and the role of fibrinogen in the biologic activities of trehalose 6,6'-dimycolate monolayers.

Identification of the physiologically active state of the mycobacterial glycolipid trehalose 6,6'-dimycolate and the role of fibrinogen in the biologic activities of trehalose 6,6'-dimycolate monolayers.

Regression of tumors by an endotoxin combined with trehalose mycolates of differing structure

A transplantable hepatocarcinoma of guinea pigs has been used as a model for study of immunotherapy of malignant tumors. Cures of established neoplasms have been effected with viable bacillus Calmette-Guerin (BCG); and certain microbial fractions, when presented in association with oil droplets in saline emulsion, have also caused regression of the tumors. P3, a mycobacterial glycolipid (trehalose dimycolate) related to cord factor, although itself inactive, has conferred antitumor properties on several otherwise ineffective materials, including bacterial endotoxins. In the present work, original P3 (isolated from Mycobacterium tuberculosis strain Aoyama B) and several fractions obtained similarly from different sources have been compared for ability to potentiate a particular endotoxin from a O antigen-deficient (Re) mutant of Salmonella typhimurium. All were trehalose mycolates, and all were about equally effective, despite differences in mycolic acid composition. Most significantly, one of the active glycolipids was from the fast-growing nonpathogen, Mycobacterium phlei, and two were monomycolates of trehalose.

Prevention of phagosome-lysosome fusion in cultured macrophages by sulfatides of Mycobacterium tuberculosis.

Intracellular parasites (e.g., Mycobacterium tuberculosis, Toxoplasma gondii, and some Chlamydiae) may promote their survival within the host by acting from within phagosomes to prevent phagolysosome formation, thus avoiding exposure to the lysosomal hydrolases. The present studies demonstrate that when sulfatides of M. tuberculosis (anionic trehalose glycolipids largely responsible for the neutral red reactivity of virulent strains) are administered to cultured mouse peritoneal macrophages, they accumulate in the secondary lysosomes, which are rendered incompetent for fusion with phagosomes containing suitable target particles such as viable yeasts. This antifusion effect is also exhibited when small amounts of sulfatide are introduced directly into phagosomes by attachment to the target yeasts prior to their ingestion. The sulfatides evidently exert a selective inhibitory influence on membrane fusion, analogous to what occurs typically when macrophage cultures are infected with tubercle bacilli. This effect may be due to ionic interaction between the polyanionic micelles of bacterial sulfatide and organelle membranes, modifying the latter and inducing dysfunction.

Chemical constitution of a glycolipid from [formula omitted] P.W.B

A variety of trehalose glycolipids have been isolated from natural sources, and several of these glycolipids exhibit important biological properties. These molecules also represent challenging synthetic targets due to their highly amphiphilic character, their large number of functional groups and additional chiral centres. This review highlights some of the recent advances made in the synthesis of trehalose glycolipids, and their associated biological activities.