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1. The solid-state conformation of the topical antifungal agent O -naphthalen-2-yl N -methyl- N -(3-methylphenyl)carbamothioate

   https://doi.org/10.1107/S2053229618013591  

   Ho, Douglas M.; Zdilla, Michael J. (November 2018, Acta Crystallographica Section C Structural Chemistry)

   null (Ed.)

   Tolnaftate, a classic antifungal compound, has been found to crystallize from 1:1 ( v / v ) acetone–water as large flat colorless needles in the centrosymmetric monoclinic space group P 2 1 / c . These crystals contain a 50:50 mixture of the (+ ap ,− sp ,+ ac ,− ac ) and (− ap ,+ sp ,− ac ,+ ac ) conformers. The bond lengths in the central CNOS unit are 1.3444 (19), 1.3556 (18) and 1.6567 (15) Å for C—N, C—O and C—S, respectively, and the CNOS and C 3 N moieties are flat and nearly coplanar with each other, consistent with the C—N bond possessing partial double-bond character. Tolnaftate and the four most closely related N , N -disubstituted thiocarbamates in the Cambridge Structural Database (CSD) all exist as E -conformational isomers in the solid state. Among these five compounds, tolnaftate is the only one in which the N -tolyl moiety is positioned trans to the S atom, i.e. the N -aryl substituent in each of the other compounds is positioned cis to their respective S atom. Notably, and more importantly, our experimental X-ray structure is unlike all prior theoretical models available for tolnaftate. The implication, either directly or indirectly, is that some of those theoretical models used in earlier studies to explain the spectroscopic properties of tolnaftate and to suggest which protein–ligand interactions are responsible for the binding of tolnaftate to squalene epoxidase are either inappropriate or structurally unreasonable, i.e. the results and conclusions from those prior studies are in need of critical reassessment. 

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2. Trans- species microRNA loci in the parasitic plant Cuscuta campestris have a U6-like snRNA promoter

   https://doi.org/10.1093/plcell/koad076  

   Hudzik, Collin; Maguire, Sean; Guan, Shengxi; Held, Jeremy; Axtell, Michael J (March 2023, The Plant Cell)

   Abstract Small regulatory RNAs can move between organisms and regulate gene expression in the recipient. Whether the trans-species small RNAs being exported are distinguished from the normal endogenous small RNAs of the source organism is not known. The parasitic plant Cuscuta campestris (dodder) produces many microRNAs that specifically accumulate at the host–parasite interface, several of which have trans-species activity. We found that induction of C. campestris interface-induced microRNAs is similar regardless of host species and occurs in C. campestris haustoria produced in the absence of any host. The loci-encoding C. campestris interface-induced microRNAs are distinguished by a common cis-regulatory element. This element is identical to a conserved upstream sequence element (USE) used by plant small nuclear RNA loci. The properties of the interface-induced microRNA primary transcripts strongly suggest that they are produced via U6-like transcription by RNA polymerase III. The USE promotes accumulation of interface-induced miRNAs (IIMs) in a heterologous system. This promoter element distinguishes C. campestris IIM loci from other plant small RNAs. Our data suggest that C. campestris IIMs are produced in a manner distinct from canonical miRNAs. All confirmed C. campestris microRNAs with documented trans-species activity are interface-induced and possess these features. We speculate that RNA polymerase III transcription of IIMs may allow these miRNAs to be exported to hosts. 

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3. Charmonium, B _c and X(3872) Transport at the LHC

   https://doi.org/10.1051/epjconf/202327602001  

   Wu, Biaogang; Tang, Zhanduo; He, Min; Rapp, Ralf (January 2023, EPJ Web of Conferences)

   Kim, Y.; Moon, D.H. (Ed.)

   We deploy a kinetic-rate equation to evaluate the transport of J /ψ, ψ(2 S ), B c and X (3872) in ultrarelativistic heavy-ion collisions and compare their production yields to experimental data from the Large Hadron Collider. The rate equation has two main transport parameters: the equilibrium limit and reaction rate for each state. The temperature-dependent equilibrium limits include charm- and bottom-quark fugacities based on their initial production. The reaction rates for charmonia, bottomonia and B c rely on charm- and bottomquark masses and binding energies from a thermodynamic T -matrix approach. For the X (3872) particle, internal structure information is encoded in reaction rates and initial conditions in the hadronic phase via two different scenarios: a loosely bound hadronic molecule vs. a compact tetraquark. 

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4. Caulerpa wysorii sp. nov ., a denuded Caulerpa (Chlorophyta) resembling C. sertularioides when ‘dressed’

   https://doi.org/10.1080/00318884.2020.1862563  

   Sauvage, Thomas; Wynne, Michael J.; Draisma, Stefano G.A.; Ortegón-Aznar, Ileana; Mateo-Cid, Luz Elena; Mendoza-González, A. Catalina; Martínez-Daranas, Beatriz; Fredericq, Suzanne (January 2011, Phycologia)

   null (Ed.)

   Routine DNA barcoding with the chloroplast gene tufA identified novel records of an unknown and denuded (i.e. lacking branchlets) Caulerpa species previously reported from the Florida Middle Grounds. tufA barcoding not only confirmed the matching molecular identity of this taxon with several newly collected denuded specimens from shallow habitats of the Yucatán shelf, but also with a set of plumose specimens previously collected from mesophotic depths of the West Florida shelf and recorded as Caulerpa sertularioides. Sequencing of two additional, faster-evolving DNA markers, i.e. nuclear ITS and the newly tested chloroplast-encoded rpoA, each confirmed conspecificity of the above morphotypes and the molecular separation of the new taxon from C. sertularioides and filiform species found in the region, namely C. cupressoides f. denudata and C. fastigiata. In light of our sequencing results and review of the early taxonomic history of filiform Caulerpa, we propose the description of Caulerpa wysorii sp. nov. for this new species that exhibits two distinct morphotypes in currently available collections, i.e. filiform or plumose assimilators. We also subsume C. tongaensis within the broadly distributed C. fastigiata, whose lectotype is also designated herein. In addition to Caulerpa wysorii sp. nov., we discovered yet another unknown denuded species from the Campeche Banks represented by a single specimen thus far. 

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5. Ecological and Evolutionary Origin of Costus flammulus (Costaceae): A New Species from the Montane Cloud Forests of the Volcanic Cordilleras in Northern Costa Rica

   https://doi.org/10.1600/036364423X16758877666039  

   Juárez, Pedro; Vargas, Oscar M.; Kay, Kathleen M. (March 2023, Systematic Botany)

   Abstract— Costus flammulus is a new herbaceous species endemic to montane cloud forests of the volcanic cordilleras in northern Costa Rica. Costus flammulus has been mistaken for C. wilsonii , but phylogenetic evidence demonstrates that it is closely related to the widespread lowland species C. pulverulentus . Here, we use an integrated framework of species concepts to evaluate whether C. flammulus and C. pulverulentus are distinct species. First, we re-evaluate prior phylogenetic analyses to assess whether C. flammulus bifurcated from or budded off from within C. pulverulentus and whether C. flammulus is monophyletic. We then compare phenotypic traits to determine which diagnostic vegetative and inflorescence traits can be used to identify species in herbarium specimens and examine whether floral traits may confer floral isolation. We compare pollinator assemblages to examine whether pollinator specificity may contribute to reproductive isolation. Finally, we model species distributions and climatic niche overlap to assess ecogeographic isolation. We found that C. flammulus is a monophyletic species phenotypically, ecologically, and geographically distinct from C. pulverulentus and may have speciated as a peripheral isolate at the high elevation range edge of C. pulverulentus . Several lines of evidence, such as C. pulverulentus paraphyly, range size asymmetry, and C. flammulus’ nested distribution and vegetative traits, suggest that C. flammulus budded off from a C. pulverulentus ‐like progenitor species, evolving to tolerate a colder and more seasonal montane environment. 

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