Biosynthesis of Methanopterin

9630186白色在我们这个星球上生活的不同生物的进化过程中，在负责C1单位代谢的载体辅酶的生物化学方面发生了根本性的分歧。有一组不同的C1载体辅酶，被称为修饰叶酸，已经在古菌领域的成员中被发现。目前的证据表明，这些修饰的叶酸完全取代了古细菌代谢中的典型叶酸，因此，它们能够进行其他两个领域（细菌和真核生物）中叶酸通常进行的所有生化反应。这种结构修饰的辅酶取代另一种具有相同功能的辅酶是前所未有的，因为在生化反应中使用的辅酶的结构通常被发现是相同的，而不管它们的来源如何。这个项目将试图获得答案，为什么在C1载体辅酶的结构分歧已经发生。通过研究和比较叶酸生物合成反应的细节，特别是研究最多的一种改性叶酸在古菌中的生物合成，甲烷蝶呤，可能会回答这个问题。我们这个星球上发现的所有生物都可以分为三个领域：古生菌、细菌和真核菌，它们都是从数十亿年前共同的祖先进化而来的。当这些不同领域的生物进化时，它们的新陈代谢产生了主要的基本生化差异。最近在古菌中发现的其中一种生化差异，即新的酶辅因子，是本项目的主题。这项研究可以让我们更好地了解这些差异的起源和生命的早期发展。＊＊＊

9630186 White At some time during the evolution of the different organisms living on our planet, a fundamental divergence occurred in the biochemistry of the carrier coenzymes responsible for the metabolism of C1 units. There are a group of different C1 carrier coenzymes, known as the modified folates, that have been discovered in the members of the domain Archaea. The current evidence indicates that these modified folates completely replace the typical folates in archaeal metabolism and, as a result, they are able to carry out all of the biochemical reactions normally performed by the folates in the other two domains, the Bacteria, and the Eucarya. This substitution of structurally-modified coenzymes for another coenzyme with the same function is unprecedented, since the structures of coenzymes utilized in biochemical reactions have in general been found to be the same regardless of their origin. This project will attempt to obtain answers as to why this divergence in the structures of the C1 carrier coenzymes has occurred. By studying and comparing the details of the reactions involved in the biosynthesis of folates, and especially the biosynthesis of one of the most studied modified folates in the Archaea, methanopterin, this question may be answered. %%% All of the organisms found on our planet are can be divided into three domains: Archaea, Bacteria, and Eucarya, all of which evolved from a common ancestor, billions of years ago. As the organisms in these different domains evolved, major fundamental biochemical differences in their metabolism arose. The recent discovery of one of these biochemical differences, novel enzyme cofactors in Archae, is the subject of this project. This research that may provide us with a better understanding of the origin of these differences and the early development of life. ***