Fatty acid ethyl esters of Rhizopus arrhizus. Ethyl esters of long-chain fatty acids are reported for Rhizopus arrhizus

Presence of ethyl esters of long-chain fatty acids determined for Rhizopus arrhizu

Two populations of aliphatic hydrocarbons of teratoma and habituated tissue cultures of tobacco

Paraffinic hydrocarbons in tobacco tissue culture

Phylogenetic Distribution of Fungal Sterols

BACKGROUND: Ergosterol has been considered the "fungal sterol" for almost 125 years; however, additional sterol data superimposed on a recent molecular phylogeny of kingdom Fungi reveals a different and more complex situation. METHODOLOGY/PRINCIPAL FINDINGS: The interpretation of sterol distribution data in a modern phylogenetic context indicates that there is a clear trend from cholesterol and other Delta(5) sterols in the earliest diverging fungal species to ergosterol in later diverging fungi. There are, however, deviations from this pattern in certain clades. Sterols of the diverse zoosporic and zygosporic forms exhibit structural diversity with cholesterol and 24-ethyl -Delta(5) sterols in zoosporic taxa, and 24-methyl sterols in zygosporic fungi. For example, each of the three monophyletic lineages of zygosporic fungi has distinctive major sterols, ergosterol in Mucorales, 22-dihydroergosterol in Dimargaritales, Harpellales, and Kickxellales (DHK clade), and 24-methyl cholesterol in Entomophthorales. Other departures from ergosterol as the dominant sterol include: 24-ethyl cholesterol in Glomeromycota, 24-ethyl cholest-7-enol and 24-ethyl-cholesta-7,24(28)-dienol in rust fungi, brassicasterol in Taphrinales and hypogeous pezizalean species, and cholesterol in Pneumocystis. CONCLUSIONS/SIGNIFICANCE: Five dominant end products of sterol biosynthesis (cholesterol, ergosterol, 24-methyl cholesterol, 24-ethyl cholesterol, brassicasterol), and intermediates in the formation of 24-ethyl cholesterol, are major sterols in 175 species of Fungi. Although most fungi in the most speciose clades have ergosterol as a major sterol, sterols are more varied than currently understood, and their distribution supports certain clades of Fungi in current fungal phylogenies. In addition to the intellectual importance of understanding evolution of sterol synthesis in fungi, there is practical importance because certain antifungal drugs (e.g., azoles) target reactions in the synthesis of ergosterol. These findings also invalidate use of ergosterol as an indicator of biomass of certain fungal taxa (e.g., Glomeromycota). Data from this study are available from the Assembling the Fungal Tree of Life (AFTOL) Structural and Biochemical Database: http://aftol.umn.edu

The use of phylogeny to interpret cross-cultural patterns in plant use and guide medicinal plant discovery: an example from Pterocarpus (Leguminosae)

The study of traditional knowledge of medicinal plants has led to discoveries that have helped combat diseases and improve healthcare. However, the development of quantitative measures that can assist our quest for new medicinal plants has not greatly advanced in recent years. Phylogenetic tools have entered many scientific fields in the last two decades to provide explanatory power, but have been overlooked in ethnomedicinal studies. Several studies show that medicinal properties are not randomly distributed in plant phylogenies, suggesting that phylogeny shapes ethnobotanical use. Nevertheless, empirical studies that explicitly combine ethnobotanical and phylogenetic information are scarce.In this study, we borrowed tools from community ecology phylogenetics to quantify significance of phylogenetic signal in medicinal properties in plants and identify nodes on phylogenies with high bioscreening potential. To do this, we produced an ethnomedicinal review from extensive literature research and a multi-locus phylogenetic hypothesis for the pantropical genus Pterocarpus (Leguminosae: Papilionoideae). We demonstrate that species used to treat a certain conditions, such as malaria, are significantly phylogenetically clumped and we highlight nodes in the phylogeny that are significantly overabundant in species used to treat certain conditions. These cross-cultural patterns in ethnomedicinal usage in Pterocarpus are interpreted in the light of phylogenetic relationships.This study provides techniques that enable the application of phylogenies in bioscreening, but also sheds light on the processes that shape cross-cultural ethnomedicinal patterns. This community phylogenetic approach demonstrates that similar ethnobotanical uses can arise in parallel in different areas where related plants are available. With a vast amount of ethnomedicinal and phylogenetic information available, we predict that this field, after further refinement of the techniques, will expand into similar research areas, such as pest management or the search for bioactive plant-based compounds

Microbial production of long-chain n-alkanes: Implication for interpreting sedimentary leaf wax signals

Relative distributions as well as compound-specific carbon and hydrogen isotope ratios of long-chain C-25 to C-33 n-alkanes in sediments provide important paleoclimate and paleoenvironmental information. These compounds in aquatic sediments are generally attributed to leaf waxes produced by higher plants. However, whether microbes, such as fungi and bacteria, can make a significant contribution to sedimentary long-chain n-alkanes is uncertain, with only scattered reports in the early 1960s to 1970s that microbes can produce long-chain n-alkanes. Given the rapidly expanding importance of leaf waxes in paleoclimate and paleoenvironmental studies, the impact of microbial contribution to long-chain n-alkanes in sediments must be fully addressed. In this study, we performed laboratory incubation of peat-land soils under both anaerobic and aerobic conditions in the absence of light with deuterium-enriched water over 1.5 years and analyzed compound-specific hydrogen isotopic ratios of n-alkanes. Under aerobic conditions, we find n-alkanes of different chain length display variable degrees of hydrogen isotopic enrichments, with short-chain (C-18-C-21) n-alkanes showing the greatest enrichment, followed by long-chain "leaf wax" (C-27-C-31) n-alkanes, and minimal or no enrichment for mid-chain (C-22-C-25) n-alkanes. In contrast, only the shorter chain (C-18 and C-19) n-alkanes display appreciable isotopic enrichment under anaerobic conditions. The degrees of isotopic enrichment for individual n-alkanes allow for a quantitative assessment of microbial contributions to n-alkanes. Overall our results show the microbial contribution to long-chain n-alkanes can reach up to 0.1% per year in aerobic conditions. For shorter chain n-alkanes, up to 2.5% per year could be produced by microbes in aerobic and anaerobic conditions respectively. Our results indicate that prolonged exposure to aerobic conditions can lead to substantial accumulation of microbially derived long-chain n-alkanes in sediments while original n-alkanes of leaf wax origin are degraded; hence caution must be exercised when interpreting sedimentary records of long-chain n-alkanes, including chain length distributions and isotopic ratios. (c) 2017 Elsevier Ltd. All rights reserved