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Acanthocephalan fauna are distributed globally as visceral parasites of vertebrates and arthropods. Morphological description of four known species of the newly described class Polyacanthocephala has been replete with controversies. However, Mitochondrial COI gene of two new cystacanths sequences; Polyacanthorhynchus nigerianus n.sp. (NG1 KC904074) and Polyacanthorhynchus echiyensis n.sp. (NG5 KC904075) infecting some parentenic individuals of Synodontis batensoda in Nigeria were sequenced. The resulting sequences were aligned with 36 other sequences of acanthocephalans representing three widely recognized classes; Archiacanthocephala, Palaeacanthocephala and Eoacanthocephala. The only representative of the new class Polyacanthocephala in the GenBank/NCBI Polyacanthorhynchus caballeroi (DQ089724) formed a common clade with these two new sequences. This study thus supports existence of the new class Polyacanthocephala as an independent class within Acanthocephala.

Whereas the photoinduced charge-transfer properties of electron donor-acceptor dyads are now well understood, those of symmetric conjugated architectures containing several identical donor-acceptor branches have started to be scrutinised much more recently. Here, we report on our investigation of the charge-transfer dynamics of a series of formally centrosymmetric triads consisting of a quadrupolar dihydropyrrolopyrrole core substituted with two identical diphenylethynyl lateral branches. Using a combination of time-resolved electronic and vibrational spectroscopies, we show that these molecules exhibit rich excited-state dynamics, which includes three different types of symmetry-breaking charge-transfer processes depending on the nature of the end substituents on the core and branches as well as on the solvent: (i) excited-state symmetry breaking within the core; (ii) charge transfer from the core to one of the two branches; (iii) charge transfer between the two branches. This investigation illustrates how the excited-state properties of symmetric conjugated molecules, including the nature and location of the exciton, can be controlled by fine tuning structural as well as environmental parameters., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Unnatural amino acids, and their synthesis by the late-stage functionalization (LSF) of peptides, play a crucial role in areas such as drug design and discovery. Historically, the LSF of biomolecules has predominantly utilized traditional synthetic methodologies that exploit nucleophilic residues, such as cysteine, lysine or tyrosine. Herein, we present a photocatalytic hydroarylation process targeting the electrophilic residue dehydroalanine (Dha). This residue possesses an α,β-unsaturated moiety and can be combined with various arylthianthrenium salts, both in batch and flow reactors. Notably, the flow setup proved instrumental for efficient scale-up, paving the way for the synthesis of unnatural amino acids and peptides in substantial quantities. Our photocatalytic approach, being inherently mild, permits the diversification of peptides even when they contain sensitive functional groups. The readily available arylthianthrenium salts facilitate the seamless integration of Dha-containing peptides with a wide range of arenes, drug blueprints, and natural products, culminating in the creation of unconventional phenylalanine derivatives. The synergistic effect of the high functional group tolerance and the modular characteristic of the aryl electrophile enables efficient peptide conjugation and ligation in both batch and flow conditions., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The tandem intramolecular hydroarylation of alkynes accompanied by a 1,2-aryl shift is described. Harnessing the unique electron-rich character of 1,4-dihydropyrrolo[3,2-b]pyrrole scaffold, we demonstrate that the hydroarylation of alkynes proceeds at the already occupied positions 2 and 5 leading to a 1,2-aryl shift. Remarkably, the reaction proceeds only in the presence of cationic gold catalyst, and it leads to heretofore unknown π-expanded, centrosymmetric pyrrolo[3,2-b]pyrroles. The utility is verified in the preparation of 13 products that bear six conjugated rings. The observed compatibility with various functional groups allows for increased tunability with regard to the photophysical properties as well as providing sites for further functionalization. Computational studies of the reaction mechanism revealed that the formation of the six-membered rings accompanied with a 1,2-aryl shift is both kinetically and thermodynamically favourable over plausible formation of products containing 7-membered rings. Steady-state UV/Visible spectroscopy reveals that upon photoexcitation, the prepared S-shaped N-doped nanographenes undergo mostly radiative relaxation leading to large fluorescence quantum yields. Their optical properties are rationalized through time-dependent density functional theory calculations. We anticipate that this chemistry will empower the creation of new materials with various functionalities., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

An additional sighting of newly described frog species, Fejervarya manoharani Garg and Biju, outside of the type locality along with their morphological data is reported herewith. We are also providing the whole DNA sequence of the mitochondrial genome with its gene organization as additional data to distinguish this species from its congeners. The mitogenome of F. manoharani was 17,654 bp in length. It contains 38 genes including two rRNAs, 23 tRNAs, 13 protein-coding genes and a control region. Similar to other dicroglossid frogs, a tandem duplication of tRNAMet was found. The ND5 gene was located at the 3' end of the control region like in three other Fejervarya species for which mitogenomic data are available. A rearrangement of four tRNA genes, namely Leucine, Threonine, Proline, and Phenylalanine, between ND5 and 12S rRNA, differing from other Fejervarya species, was also observed.

Research interests on amphibian antimicrobial peptides (AMPs) are currently increasing because of their capability to combat microorganisms from both terrestrial and aquatic environments, which are the warehouses of human pathogens. The most remarkable feature of AMPs are their mechanism of action, primarily targeted to anionic membranes. Researchers have postulated many models to describe peptide- membrane interaction, which leads to membrane permeation/intracellular targeting. Despite these models information regarding the relationship between membrane curvature and peptidemembrane interaction is scarce. This relationship could be clearly depicted using the two-state model and interfacial activity model. In the review, we discuss in detail the two state and interfacial activity models and explain the influence of membrane curvature on peptide binding and the membrane interaction of curvature-sensitive peptides. In addition, the models proposed to explain the mechanism of action of membrane lytic and non-lytic AMPs are also reviewed., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)