mycobacterium tuberculosis rv3802c encodes a phospholipasethioesterase and is inhibited by the antimycobacterial agent tetrahydrolipstatin结核分枝杆菌rv3802c编码phospholipasethioesterase,抗细菌剂tetrahydrolipstatin抑制.pdfVIP

Mycobacterium tuberculosis Rv3802c Encodes a Phospholipase/Thioesterase and Is Inhibited by the Antimycobacterial Agent Tetrahydrolipstatin 1 3 1 2 Sarah K. Parker *, Robert M. Barkley , John G. Rino , Michael L. Vasil 1 Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, United States of America, 2 Department of Microbiology, University of Colorado Denver, Aurora, Colorado, United States of America, 3 Department of Pharmacology, University of Colorado Denver, Aurora, Colorado, United States of America Abstract The cell wall of M. tuberculosis is central to its success as a pathogen. Mycolic acids are key components of this cell wall. The genes involved in joining the a and mero mycolates are located in a cluster, beginning with Rv3799c and extending at least until Rv3804c. The role of each enzyme encoded by these five genes is fairly well understood, except for Rv3802c. Rv3802 is one of seven putative cutinases encoded by the genome of M. tuberculosis. In phytopathogens, cutinases hydrolyze the waxy layer of plants, cutin. In a strictly mammalian pathogen, such as M. tuberculosis, it is likely that these proteins perform a different function. Of the seven, we chose to focus on Rv3802c because of its location in a mycolic acid synthesis gene cluster, its putative essentiality, its ubiquitous presence in actinomycetes, and its conservation in the minimal genome of Mycobacterium leprae. We expressed Rv3802 in Escherichia coli and purified the enzymatically active form. We probed its activities and inhibitors characterizing those relevant to its possible role in mycolic acid biosynthesis. In addition to its reported phospholipase A activity, Rv3802 has significant thioesterase activity, and it is inhibited by tetrahydroli