Month: September 2022

ESSENTIAL ELEMENT. “Phosphate is present in a large proportion of known biomolecules. It is an essential component of biochemical energy transduction (most notably through ATP), cofactors such as NADH, and information storage (in DNA and RNA polymers).” https://lnkd.in/dcwZe7b View in LinkedIn

INACCESSIBILITY. “However, phosphate is geochemically scarce and difficult to access, often serving as the limiting nutrient in a variety of modern ecosystems. Phosphate is found in terrestrial and marine ecosystems, tightly complexed with rocks and minerals, requiring mechanisms for environmental extraction and transport.” https://lnkd.in/dcwZe7b View in LinkedIn

ENIGMA VARIATIONS. “The ensuing dilemma of phosphate’s high importance in spite of its poor bioavailability is particularly challenging for early life, as primordial protocells would have needed both a readily available phosphate source and a simple mechanism for early phosphate acquisition.” https://lnkd.in/dcwZe7b View in LinkedIn

HYPOTHESES. “Currently, there is no consensus for a phosphate source in early life, with theories ranging from acid-mediated ion solubilization, high concentrations of reduced phosphorus species in early oceans, or accumulation during late heavy bombardment.” https://lnkd.in/dcwZe7b View in LinkedIn

MECHANISM. “Even provided a phosphate source, the mechanisms of phosphate utilization and polymerization in early life remain debated.” https://lnkd.in/dcwZe7b View in LinkedIn

PROPOSED HYPOTHESIS. “The alternative solution to this dilemma is that primitive forms of life could have initially emerged and endured without a major dependence on phosphate. Multiple scenarios for early metabolic pathways that do not rely on phosphate have been proposed.” https://lnkd.in/dcwZe7b View in LinkedIn

PHOSPHATE SURROGATES. “In many of these scenarios, sulfur and iron are conjectured to have fulfilled major catalytic and energetic functions prior to the appearance of phosphate.” https://lnkd.in/dcwZe7b View in LinkedIn

SURROGATE MOLECULES. “Most notably, in the thioester world scenario, thioesters are hypothesized to have played a role similar to the one played today by ATP. Thioesters are widespread in modern metabolism, primarily as Coenzyme A (CoA) derivatives (e.g., Acetyl-CoA), and are used as condensing agents, enabling the synthesis of heterogeneous biopolymers.” https://lnkd.in/dcwZe7b View in LinkedIn

PRECEDENT. “The thioester world hypothesis, and other phosphate-independent protometabolism models, are typically invoked to explain the prebiotic plausibility of general biochemical mechanisms, and are illustrated through specific reactions or pathways.” https://lnkd.in/dcwZe7b View in LinkedIn

HUGE STUDY. “Here we address these questions using computational systems biology approaches originally developed for performing large-scale analyses of complex metabolic networks.” https://lnkd.in/dcwZe7b View in LinkedIn