title: The prenylation inhibitor manumycin A reduces the viability of Anaplasma phagocytophilum.
abstract: Anaplasma phagocytophilum is an obligately intracellular bacterium and is the causative agent of human granulocytic anaplasmosis (HGA), an emerging and major tick-borne disease in the USA and other parts of the world. This study showed that the prenylation inhibitor manumycin A effectively blocked A. phagocytophilum infection in host cells (HL-60 or RF/6A cells). A. phagocytophilum infection activated extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase in host cells, and manumycin A treatment reduced ERK activation in A. phagocytophilum-infected host cells. As ERK activation is required for A. phagocytophilum infection, we examined whether manumycin A inhibited the bacteria directly or through host ERK signalling. Treatment of A. phagocytophilum alone with manumycin A significantly reduced the bacterial infectivity of host cells and bacterial viability in the absence of host cells, whereas pre-treatment of host cells did not inhibit bacterial infection in host cells. The inhibitory effect of manumycin A on A. phagocytophilum infection in host cells was achieved even at a concentration 100 times lower than that required for effective inhibition of mammalian cell signalling. These results suggested that manumycin A directly inactivates the bacterium, resulting in reduced infection and ERK1/2 activation. Thus, the manumycin group of drugs may have a therapeutic potential for HGA.
authors.affiliation: Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, 1925 Coffey Road, Columbus, OH 43210, USA.
authors.forename: Qingming
authors.initials: Q
authors.lastname: Xiong
authors.affiliation: Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, 1925 Coffey Road, Columbus, OH 43210, USA.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Rikihisa
mesh_terms: D041081:Anaplasma phagocytophilum / Q000187:drug effects*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002460:Cell Line; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D006801:Humans; D050296:Microbial Viability / Q000187:drug effects*; D011090:Polyenes / Q000494:pharmacology*; D053284:Polyunsaturated Alkamides / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D011090:Polyenes; D053284:Polyunsaturated Alkamides; D048049:Extracellular Signal-Regulated MAP Kinases; C054474:manumycin