Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536, Universite Bordeaux Segalen, CNRS, Bordeaux, France.
Front Biosci (Landmark Ed). 2012 Jan 1;17(1):349-74. doi: 10.2741/3931.
Trypanosomatids are a large family of unicellular eukaryotes, many of which are parasites in higher eukaryotes including man. Much of our understanding of metabolism in these organisms has been gained form the study of the human infective representatives (Trypanosoma brucei subpecies, Trypanosoma cruzi and Leishmania spp.) which are transmitted by blood-feeding arthropods. The insect vectors of these parasites use proline as a principal carbon and energy source circulating in their haemolymph. Accordingly the insect-forms of the human infectious parasites have evolved to exploit abundant proline when in this environment, but being able to activate different biochemical pathways when in other environments. Interestingly, if glucose is available, metabolic capability can shift to make this carbohydrate the preferred substrate. Proline has also been shown to play key roles in osmoregulation, differentiation in representatives of the group and may even play a role in immunosuppression elicited by the American trypanosome T. cruzi. This review focuses on recent progress in understanding the different aspects of proline metabolism in trypanosomatids, with a particular interest on the insect forms.
锥虫是一个大型的单细胞真核生物家族，其中许多是包括人类在内的高等真核生物的寄生虫。我们对这些生物体代谢的了解主要来自于对人类传染性代表（布氏锥虫亚种、克氏锥虫和利什曼原虫属）的研究，这些寄生虫通过吸血节肢动物传播。这些寄生虫的昆虫媒介使用脯氨酸作为主要的碳和能源源，在其血液中循环。因此，在这种环境下，人类传染性寄生虫的昆虫形式已经进化到能够利用丰富的脯氨酸，但在其他环境中能够激活不同的生化途径。有趣的是，如果有葡萄糖可用，代谢能力可以转变为使这种碳水化合物成为首选底物。脯氨酸还被证明在渗透压调节、该组代表的分化中发挥关键作用，甚至可能在美洲锥虫 T. cruzi 引起的免疫抑制中发挥作用。本综述重点介绍了在理解锥虫生物中脯氨酸代谢的不同方面的最新进展，特别关注昆虫形式。
