S-Adenosylmethionine (AdoMet) is an important methyl group donor that plays a central role in many essential biochemical processes. The parasite Leishmania can both synthesize and transport AdoMet. Leishmania cells resistant to the antifolate methotrexate due to a rearrangement in folate biopterin transporter (FBT) genes were cross-resistant to sinefungin, an AdoMet analogue. FBT gene rearrangements were also observed in Leishmania major cells selected for sinefungin resistance. One of the rearranged FBT genes corresponded to the main AdoMet transporter (AdoMetT1) of Leishmania as determined by gene transfection and gene inactivation experiments. AdoMetT1 was determined to be a high affinity plasma membrane transporter expressed constitutively throughout the growth phases of the parasite. Leishmania cells selected for resistance or naturally insensitive to sinefungin had lower expression of AdoMetT1. A new function in one carbon metabolism, also a pathway of interest for chemotherapeutic interventions, is described for a novel class of membrane proteins found in diverse organisms.
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http://dx.doi.org/10.1074/jbc.M110.114520 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Institute of Science and Technology Austria, AT-3400 Klosterneuburg, Austria.
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Laboratory of Precision Medicine and Biopharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.
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Department of Traditional Chinese Medicine, Shanghai Fourth People's Hospital Affiliated to Tongji University of Medicine, Shanghai, China.
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Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases Ministry of Education, Jiangxi Province Key Laboratory of Biomaterials and Biofabrication for Tissue Engineering, Gannan Medical University, Ganzhou, 341000, Jiangxi, China.
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