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Colpomenia peregrina Sauvageau has a biphasic, heteromorphic life history alternated with saccate gametophytes and crustose sporophytes. The circular C. peregrina mitogenome is 36,025 bp in length and encodes 66 genes, including 3 ribosomal RNA genes (rRNA), 25 transfer RNA genes (tRNA), 35 protein-coding genes, and 3 open reading frames (ORFs). It is the shortest and most compact of the sequenced Ectocarpales mitogenomes to date. The overall A + T content in C. peregrina mitogenome is 68.01%, higher than that of other reported Ectocarpales species (62.01–66.49%). The total intergenic spacers are 1499 bp, constituting 4.16% of the whole genome. Genome organization of C. peregrina is essentially identical to that of known Ectocarpales species, except for Pylaiella littoralis. Phylogenetic analyses based on 35 protein-coding genes show that Scytosiphon lomentaria and Petalonia fascia firstly cluster together, and then group with C. peregrina forming the Scytosiphon-Petalonia-Colpomenia subclade with high support values, indicating their close evolutionary relationships.

Succession in an intertidal benthic community affected by untreated sewage effluent: A case of study in the SW Atlantic shore

We investigated the cytotoxic, neurotoxic, apoptotic and antiproliferative effects of extracts from Petalonia fascia, Jania longifurca and Halimeda tuna on the MCF-7 breast cancer cell line. J. longifurca extracts were more toxic than those of P. fascia and H. tuna. The algal extracts showed significant toxic effects at different dilutions. The toxic effects were due to increased oxidative stress and resulted in apoptosis. Algal toxicity may exert negative effects through the food chain or by direct interaction. Algal toxicity also has potential for cancer therapy. The toxic effects that we observed may be especially important for therapy for breast tumors.

Using a mild detergent, octyl sucrose, light-harvesting fucoxanthin-Chl a/c-protein complexes of a brown alga, Petalonia fascia, were isolated in the form of supramolecular assemblies. Negatively stained images of these assemblies (FCPAs) were extremely uniform in size and shape. Each was discoidal in shape, being 11.2 nm in diameter and 10.2 nm in height, with a small pit at the center of disc (...)

ABSTRACTChromosome numbers for three species of Scytosiphonaceae from the warm temperate coast of North Carolina are presented. Petalonia fascia (O. F. Mueller) Kuntze, P. zosterifolia (Reinke) Kuntze, and Scytosiphon lomentaria (Lyngbye) C. Agardh were all found to have twenty‐two chromosomes in both macro‐ and microthallus stages. The uniformity of chromosome numbers and morphology for all three taxa suggest a close genetic relationship and possible common ancestry.Evidence of synchronous mitotic divisions is presented for the first time in the Phaeophyta. Both field collected and culture material of P. fascia and P. zosterifolia exhibited a 2–4 h post‐sunset peak in nuclear divisions. In actively growing macrothalli, up to 8% of the observed cells were found in some stage of mitosis. Data suggest that mitosis and the entire sequence of cytokinesis require approximately 2 h.