POLYAMINES IN TRYPANOSOMES--FUNCTION AND METABOLISM

S-腺苷蛋氨酸脱羧酶抑制剂5‘{[(Z)4- 氨基-2-丁烯基]甲氨基-5-脱氧腺苷(MDL73811)，治疗药物 模型感染中的难治性罗氏结核杆菌临床分离株；以及 通过嘌呤转运体被主动吸收。我们将研究这种模式 了解这些药物的作用，并确定其他潜在的候选药物。 MDL73811和DFMO都大幅提升了ADOMet，因为 ADOMet合成酶。ADOMet是亚精胺的氨丙基供体 大多数甲基转移酶的合成和甲基供体。我们相信 处理过的寄生虫(不在宿主中)中的极高(5 Mm)ADOMet池 细胞)导致细胞成分的高度甲基化。 [~(35)S]蛋氨酸通过ADOMet，腺苷同型半胱氨酸(ADOHcy)的流动 并增加了U[14C]的掺入，而不是 [35S]甲硫基腺苷。我们会研究： 1.T.B.rodesiense抗砷无性系的能力 要运输基于嘌呤核苷的ADOMet、ADOHcy和 甲硫腺苷， 2.用多胺分配蛋氨酸环中间体， 转甲基化和转硫化抑制剂， 3.检测正常和药物中蛋白质和磷脂的甲基化 处理细胞，并确定在治疗过程中升高的ADOMet水平 治疗会导致甲基化， 4.细长(LS)基因转化过程中的反甲基化 从血型到原环型，我们将监测变种的释放 LS型表面糖肽与原环素a的研究进展 原环形式的表面蛋白，以及 5.DFMO耐药变多胺或罗德氏菌分离株 转甲基化模式， 这项工作将利用在培养中生长的血型；高效液相色谱法和 放射检测研究ADOMet和蛋氨酸及等电点的去向 专注于识别甲基化的蛋白质。 我们希望确定转甲基酶的作用(S)及其控制 非洲锥虫及其在生命周期中的重要性。

The S-Adenosylmethionine (AdoMet) decarboxylase inhibitor 5'{[(Z) 4- amino-2-butenyl]methyamino}-5-deoxyadenosine (MDL73811), cures drug refractory T. b. rhodesiense clinical isolates in model infections; and is actively taken up via a purine transporter. We will study the mode of action of these agents and identify other potential drug candidates. Both MDL73811 and DFMO dramatically elevate AdoMet due to an unregulated AdoMet synthetase. AdoMet is aminopropyl group donor for spermidine synthesis and methyl group donor for most methyltransferases. We believe the extremely high (5mM) AdoMet pools in treated parasites (not in host cells) leads to hypermethylation of cell components. The flow of [35S]methionine through AdoMet, adenosylhomocysteine (AdoHcy) and increased incorporation of U[14C] as opposed to [35S]methylthioadenosine. We will study: 1. The ability of arsenical drug resistant clones of T. b. rhodesiense to transport purine nucleoside-based analogs of AdoMet, AdoHcy and methylthioadenosine, 2. Partitioning of methionine cycle intermediates by use of polyamine, transmethylation and transsulfuration inhibitors, 3. Examine protein and phospholipid methylation in normal and drug treated cells, and determine whether elevated AdoMet levels during treatment result in hypermethylation, 4. Transmethylation during transformation of long slender (LS) bloodforms to procyclic forms, we will monitor the release of variant surface glycopeptide from LS forms and the development of procyclin a surface protein of procyclic forms, and 5. DFMO refractory T. b. rhodesiense isolates for altered polyamine or transmethylation patterns, This work will utilize bloodforms grown in culture; HPLC and radiodetection to study the fate of AdoMet and methionine and isoelectric focusing to identify methylated proteins. We hope to determine the roles(s) of transmethylases and their control in African trypanosomes and their importance in the life cycle.