Serpentinization-Associated Mineral Catalysis of the Protometabolic Formose System

The formose reaction is a plausible prebiotic chemistry, famed for its production of sugars. In this work, we demonstrate that the Cannizzaro process is the dominant process in the formose reaction under many different conditions, thus necessitating a catalyst for the formose reaction under various environmental circumstances. The investigated formose reactions produce primarily organic acids associated with metabolism, a protometabolic system, and yield very little sugar left over. This is due to many of the acids forming from the degradation and Cannizaro reactions of many of the sugars produced during the formose reaction. We also show the heterogeneous Lewis-acid-based catalysis of the formose reaction by mineral systems associated with serpentinization. The minerals that showed catalytic activity include olivine, serpentinite, and calcium, and magnesium minerals including dolomite, calcite, and our Ca/Mg-chemical gardens. In addition, computational studies were performed for the first step of the formose reaction to investigate the reaction of formaldehyde, to either form methanol and formic acid under a Cannizzaro reaction or to react to form glycolaldehyde. Here, we postulate that serpentinization is therefore the startup process necessary to kick off a simple proto metabolic system—the formose protometabolic system

CaCO3 Polymorphs as Mineral Catalysts for Prebiotic Phosphorylation of Uridine Data Files

Manuscript and data files published in Earth and Space ScienceEstablishing plausible routes for the abiotic formation of nucleotides is a challenging problem because the phosphorylation of organic molecules is thermodynamically unfavorable in water, and because common phosphorous-containing minerals such as apatite are highly insoluble. Reactions of reduced phases such as the meteoritic mineral schreibersite with ammonia containing solutions can form stable amino-derivatives of phosphates/phosphite, and carbonate-rich lakes have been suggested as environments where phosphate species and organic molecules could accumulate in significant abundances, thus promoting an ideal environment for abiotic phosphorylation. This work reports the catalytic properties of three CaCO3 polymorphs – calcite, aragonite, and vaterite – on diamidophosphate (DAP)-induced phosphorylation of the uridine nucleoside during a 24-hour dry-down reaction. It is shown that the phosphorylation reaction is accelerated in solutions containing CaCO3 compared to those with no mineral present. For un-buffered solutions with no mineral present, the primary products formed are uridine monophosphates (UMP), with yields making up 22.3 ± 3.9% of the total detected species, while solutions containing calcite and aragonite formed primarily UMP dimers (yields of 15.3 ± 1.1% and 14.8 ± 1.3%, respectively). Vaterite showed a strong preference for forming cyclic UMP (cUMP) (26.3 ± 0.3% yield), and no higher order polymers were observed using any carbonate mineral. Reactions containing CaSO4∙2H2O (gypsum) showed a preference for forming cUMP, though not as strong as vaterite, while those containing CaCl2 (calcium chloride) and CaWO4 (scheelite) did not yield any phosphorylated products other than UMPs. These results suggest that CaCO3 minerals could have played an important role in facilitating prebiotic phosphorylation in aqueous environments that undergo drying cycles.National Science Foundation Center for Chemical Evolution (CHE-1504217

Origins of Life: Chemistry and Evolution

Our understanding of the origins of life will be enhanced if models and their predictions are clearly understood and explicitly articulated. Here we outline two distinct models that are currently used to explain the origins of life. In one model, which has been pursued for a half century, inherent chemical reactivities of prebiotic chemical species produced RNA, which then invented evolution. This direct synthesis model enables the prediction that if the conditions of the ancient earth are sufficiently constrained, chemists will discover the synthetic pathways that produced RNA. In a fundamentally different model, which is more recent and less mature, RNA in concert with other biopolymers arose from prolonged, selection-based changes that occurred during chemical evolution, which transitioned smoothly into biological evolution. This evolutionary model predicts common chemistry of linkage and amazing structures, assemblies and co-assemblies, as represented by double stranded DNA, tRNA, cellulose, collagen, globular proteins, ATP synthase, and the ribosome. This evolutionary model predicts profound integration of biological subsystems as represented by ATP, which is central to and inextricable from biopolymer structure and biosynthesis and metabolic systems. In the evolutionary model, inherent chemical reactivities of biological building blocks are not necessarily relevant to the origins of life and do not predict biosynthesis. The two models of the origins of life are fundamentally different from one another and guide design of very different experimental approaches to test their underlying assumptions. It is currently undetermined which model, or a hybrid of them, is closer to reality

Biogenic Orthorhombic α-Calcium Formate from Sediments of Alkali Lake, Oregon, USA

Centimeter-sized crystals of orthorhombic calcium formate, α-Ca(HCO2)2 from Alkali Lake, Oregon, USA have been studied by means of powder and single-crystal X-ray diffraction analysis, infrared, and Raman spectroscopy. Based on the data on carbon isotope abundance in calcium formate and associated minerals, it was concluded that the formation of α-Ca(HCO2)2 may be a result of a combination of two factors: lake microbial metabolism and anthropogenic pollution with Agent Orange. Possible causes of stability of the low-density tetragonal β-Ca(HCO2)2 polymorph (formicaite) in boron ores are discussed

Review of the El Soplao Amber Outcrop, Early Cretaceous of Cantabria, Spain

International audienceEl Soplao outcrop, an Early Cretaceous amber deposit recently discovered in northern Spain (Cantabria), has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far. Relevant data provided herein for biogeochemistry of the amber, palynology, taphonomy and arthropod bioinclusions complement those previously published. This set of data suggests at least two botanical sources for the amber of El Soplao deposit. The nrst (type A amber) strongly supports a source related to Cheirolepidiaceae, and the second (type B amber) shows non-specific conifer biomarkers. Comparison of molecular composition of type A amber with Frenelopsis leaves (Cheirolepidiaceae) strongly suggests a biochemical affinity and a common botanical origin. A preliminary palynologlcal study indicates a regional high taxonomical diversity, mainly of pteridophyte spores and gymnosperm pollen grains. According to the preliminary palynologlcal data, the region was inhabited by conifer forests adapted to a dry season under a subtropical climate. The abundant charcoalified wood associated with the amber in the same beds is evidence of paleofires that most likely promoted both the resin production and an intensive erosion of the litter, and subsequent great accumulation of amber plus plant cuticles. In addition, for the first time in the fossil record, charcoalified plant fibers as bioinclusions in amber are reported. Other relevant taphonomic data are the exceptional presence of serpulids and bryozoans on the surfaces of some amber pieces indicating both a long exposure on marine or brackish-water and a mixed assemblage of amber. Lastly, new findings of insect bioinclusions, some of them uncommon in the fossil record or showing remarkable adaptations, are reported. In conclusion, a documented scenario for the origin of the El Soplao amber outcrop is provided

Evaluation of AIF-1 (Allograft Inflammatory Factor-1) as a Biomarker of Crohn’s Disease Severity

Background: Recently, increased tissue levels of AIF-1 have been shown in experimental colitis, supporting its role in intestinal inflammation. Therefore, we studied the levels of AIF-1 in Crohn’s disease (CD). Methods: This study included 33 patients with CD (14 men and 19 women) who participated in the PREDICROHN project, a prospective multicenter study of the Spanish Group of Inflammatory bowel disease (GETECCU). Results: This article demonstrates declines with respect to baseline levels of serum AIF-1 in Crohn’s disease (CD) patients after 14 weeks of treatment with anti-TNFs. Furthermore, in patients with active CD (HB ≥ 5), serum AIF-1 levels were significantly higher than those in patients without activity (HB ≤ 4). The study of serum AIF-1 in the same cohort, revealed an area under the ROC curve (AUC) value of AUC = 0.66 (p = 0.014), while for the CRP (C-reactive protein), (AUC) value of 0.69 (p = 0.0066), indicating a similar ability to classify CD patients by their severity. However, the combination of data on serum levels of AIF-1 and CRP improves the predictive ability of these analyses for classifying CD patients as active (HB ≥ 5) or inactive (HB ≤ 4). When we used the odds ratio (OR) formula, we observed that patients with CRP > 5 mg/L or AIF-1 > 200 pg/mL or both conditions were 13 times more likely to show HB ≥ 5 (active CD) than were those with both markers below these thresholds. Conclusion: The development of an algorithm that includes serum levels of AIF-1 and CRP could be useful for assessing Crohn’s disease severity