A Family of Dual-Activity Glycosyltransferase-Phosphorylases Mediates Mannogen Turnover and Virulence in Leishmania Parasites.

A Family of Dual-Activity Glycosyltransferase-Phosphorylases Mediates Mannogen Turnover and Virulence in Leishmania Parasites. Cell Host Microbe. 2019 Sep 11;26(3):385-399.e9 Authors: Sernee MF, Ralton JE, Nero TL, Sobala LF, Kloehn J, Vieira-Lara MA, Cobbold SA, Stanton L, Pires DEV, Hanssen E, Males A, Ward T, Bastidas LM, van der Peet PL, Parker MW, Ascher DB, Williams SJ, Davies GJ, McConville MJ Abstract Parasitic protists belonging to the genus Leishmania synthesize the non-canonical carbohydrate reserve, mannogen, which is composed of β-1,2-mannan oligosaccharides. Here, we identify a class of dual-activity mannosyltransferase/phosphorylases (MTPs) that catalyze both the sugar nucleotide-dependent biosynthesis and phosphorolytic turnover of mannogen. Structural and phylogenic analysis shows that while the MTPs are structurally related to bacterial mannan phosphorylases, they constitute a distinct family of glycosyltransferases (GT108) that have likely been acquired by horizontal gene transfer from gram-positive bacteria. The seven MTPs catalyze the constitutive synthesis and turnover of mannogen. This metabolic rheostat protects obligate intracellular parasite stages from nutrient excess, and is essential for thermotolerance and parasite infectivity in the mammalian host. Our results suggest that the acquisition and expansion of the MTP family in Leishmania increased the metabolic flexibility of these protists and contribute...
Source: Cell Host and Microbe - Category: Microbiology Authors: Tags: Cell Host Microbe Source Type: research