Did Nature use Reduced Oxidation State Phosphorus in Prebiotic Chemistry? Strengthening the Case for a Non-Phosphate World prior to the RNA-World

磷酸盐是地球上所有生命的关键成分。磷酸盐在地球上无处不在，我们把它作为钙盐从地下挖出来，我们用它来刷牙，我们每天在食物和饮料中消耗它。然而，尽管磷酸盐是一种相当常见的化学物质，但我们绝不能肯定，大自然为地球上最早的生命形式选择了磷酸盐。问题的很大一部分是，磷酸盐化学物质极不溶，化学反应也很迟钝。1955年，科学家Addison Gulick提出，如果早期地球上有其他形式的磷，这个磷酸盐问题就可以解决。这些化学物质被称为膦酸盐和膦酸盐，是磷酸盐的近亲，但它们在水中更容易溶解，也更容易发生化学反应。问题是，膦酸盐和膦酸盐在今天的地球上是未知的，因为几千年来，地球的化学环境已经发生了很大的变化，现在只有磷酸盐是稳定的。然而，我们最近发现，在早期地球上，通过富铁陨石与水在光照下的化学反应，磷酸盐和膦酸盐可能很容易用于生命前化学。这一发现使我们第一次能够详细探索磷酸盐和膦酸盐在生命起源问题中的潜力，并在一定程度上确信这种化学物质可能在早期地球上存在。本项目分为两部分。在第1部分中，我们将详细介绍磷酸盐和膦酸盐是如何从实际陨石碎片的化学改性中形成的。在第二部分中，我们探索了可能在早期地球上与这两种磷发生的潜在化学反应，以及可能对一些关键生物分子（如益生元有机磷聚合物）如何出现产生影响的化学反应。

Phosphate is a key ingredient in all life on Earth. Phosphate is everywhere on Earth, we dig it out of the ground as a calcium salt, we use it to brush our teeth, we consume it in food and drink every day. However, despite it being a rather common chemical, it is by no means certain that Nature chose phosphate for the earliest forms of life on Earth. A large part of the problem is that phosphate chemicals are both extremely insoluble and very unreactive chemically. In 1955, the scientist Addison Gulick proposed that this phosphate problem could have been solved if other forms of phosphorus were available on the early Earth. These chemicals, called phosphonates and phosphinates, are close relatives of phosphate but are both more soluble and chemically reactive in water. The problem is that phosphonates and phosphinates are unkown on Earth today because over the millennia, the chemical environment of Earth has changed to such a degree that only phosphates are now stable. However, we have recently discovered that phosphinates and phosphonates could have been readily available to prebiotic chemistry on the early Earth through chemical reactions of iron-rich meteorites with water in the presence of light. This discovery allows us to explore in detail the potential of phosphonates and phosphinates in the origin-of-life problem for the first time with a degree of confidence that such chemistry could have been available on the early Earth.This project is built in two parts. In Part 1 we will look in detail at how exactly phosphonates and phosphinates were formed from the chemical modification of actual meteorite fragments. In Part 2, we explore potential chemical reactions which could have taken place on an early Earth with these two phosphorus species and which could have an impact in how some of key biological molecules, such as prebiotic organic phosphorus polymers, might have emerged.