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Made available in DSpace on 2022-04-29T08:46:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Gracilariales is a clade of florideophycean red macroalgae known for being the main source of agar. We present a de novo genome assembly and annotation of Gracilaria domingensis, an agarophyte alga with flattened thallus widely distributed along Central and South American Atlantic intertidal zones. In addition to structural analysis, an organizational comparison was done with other Rhodophyta genomes. The nuclear genome has 78 Mbp, with 11,437 predicted coding genes, 4,075 of which did not have hits in sequence databases. We also predicted 1,567 noncoding RNAs, distributed in 14 classes. The plastid and mitochondrion genome structures were also obtained. Genes related to agar synthesis were identified. Genes for type II galactose sulfurylases could not be found. Genes related to ascorbate synthesis were found. These results suggest an intricate connection of cell wall polysaccharide synthesis and the redox systems through the use of L-galactose in Rhodophyta. The genome of G. domingensis should be valuable to phycological and aquacultural research, as it is the first tropical and Western Atlantic red macroalgal genome to be sequenced. Laboratory of Algal Biochemistry and Molecular Biology Department of Biochemistry Institute of Chemistry University of São Paulo, Av. Prof. Lineu, Prestes, 748, SP CNRS UMR 7232 Biologie Intégrative des Organismes Marins (BIOM) Sorbonne Université, Observatoire Océanologique - F-66650 Department of Botany Institute of Biosciences University of São Paulo, R Matão 277, SP Departamento de Bioquímica y Biología Molecular Facultad de Ciencias Químicas y Farmacéuticas Universidad de Chile Universidad de Chile - Independencia Department of Oceanography and Limnology Federal University of Rio Grande do Norte - Via Costeira, Praia de Mãe Luiza, s/n, RN Phycology Research Center Institute of Botany Secretary of Infrastructure and Environment of São Paulo State, Brazil - Av. Miguel Estefano, 3687, Água Funda, SP School of Pharmaceutical Sciences São Paulo State University (UNESP), Rod. Araraquara-Jaú km 1, Campus Ville, SP Station Biologique de Roscoff UMR 8227 Integrative Biology of Marine Models - CS 90074 Department of Biochemistry Institute of Chemistry University of São Paulo, Av. Prof. Lineu Prestes, 748, SP School of Pharmaceutical Sciences São Paulo State University (UNESP), Rod. Araraquara-Jaú km 1, Campus Ville, SP

) Recursos de Divisa˜o Microbianos, Centro Pluridisciplinar de Pesquisas Qumicas, Biolo´gicas eAgrcolas, CPQBA, Universidade Estadual de Campinas, Rua Alexandre Casellato, 999,CEP 13140-000, Paulnia-SP, BrazilThe biocatalytic reduction of acetophenone derivatives was exploited by using algal biomass fromBostrychia radicans and B. tenella producing exclusively (S)-2-phenylethanols with high enantiomericexcess (>99% ee). Bacterial populations associated with algal biomass were identified as the Bacillusgenus. This report deals with the first investigations involving the use of marine bacteria associated withB. radicans and B. tenella marine algae for the biocatalytic reduction of acetophenone derivatives.

Endogenous cytokinins, auxins, and abscisic acid (ABA) were identified and quantified in 11 red algae collected from the Brazilian coast. Field materials and two isolates cultured in the laboratory were extracted with various solvents and buffers containing a mixture of appropriate internal standards, purified by solid-phase extraction followed by immunoaffinity chromatography, and analyzed by liquid chromatography–tandem mass spectrometry. Isoprenoid cytokinins (free and conjugated forms of isopentenyladenine [iP], cis-zeatin [cZ], and trans-zeatin [tZ]) were detected in all species with concentrations of cZ and iP forms being higher than tZ forms. Dihydrozeatin (DHZ) and its metabolites were only detected at very low levels in nine of the studied species. Aromatic cytokinins (6-benzylaminopurine [BA], ortho- and meta-topolin [oT and mT]) were not detected in any of the samples. The cytokinin profile of Chondracanthus teedei (Mert. ex Roth) Kutz. was distinct in comparison to other species with para-topolin (pT) derivatives detected in low concentrations. The main auxins present in all species were free indole-3-acetic acid (IAA) and indole-3-acetamide (IAM). Indole-3-ethanol (IEt), indole-3-acetyl glutamic acid (IAGlu), and indole-3-acetyl leucine (IALeu) were detected in a few species at low concentrations. ABA was present in all species analyzed except for Hypnea nigrescens Grev. ex J. Agardh. No ABA conjugates were detected in any species. These results confirm that cytokinins, auxins, and ABA were common constituents in red seaweeds, with this being the first report of the occurrence of ABA in Rhodophyta. The complexity of the hormone profiles suggests that plant hormones play a role in regulating physiological processes in Rhodophyta.

OBJECTIVE The purpose of this study was to evaluate the correlation between the radiographic and ultrasonographic measurements of craniocaudal displacement of the left hemidiaphragm. METHODS Forty-nine patients with clinical indications for interventional procedures prospectively underwent radiographic evaluation of left hemidiaphragmatic mobility and B-mode ultrasonographic measurement of craniocaudal displacement of the hilum and the inferior pole of the spleen. Ultrasonography was performed with a 3.5-MHz convex transducer in a left intercostal position under a longitudinal orientation. Statistical analyses were performed with linear regression, a paired Student t test, and Bland-Altman analyses. RESULTS The correlation between the craniocaudal splenic hilum displacement and radiographic measurements was found to be linear: hemidiaphragmatic mobility = 17.795 + 0.429 x splenic hilum displacement (SE for the regression coefficient = 0 .12; P = .0012), although the values obtained with both methods were statistically different (P < .05). The same results could be observed with the use of the inferior pole of the spleen: hemidiaphragmatic mobility = 9.5596 + 0.5455 x inferior polo displacement (SE for the regression coefficient = 0 .11; P < .0001). The mean difference between the values obtained by ultrasonography and by radiography was statistically significant (16.7 +/- 16.1 mm; P < .05 [hilum]; 18.9 +/- 14.2 mm; P < .05 [inferior pole]). CONCLUSIONS These results allow us to conclude that ultrasonography can be used as an alternative method for left hemidiaphragm mobility evaluation compared with radiography.

SUMMARY The effects of auxins and cytokinin on callus formation, growth and regeneration of Gracilaria tenuistipitata Chang et Xia and G. perplexa Byrne et Zuccarello (Gracilariales, Rhodophyta) are reported. Plant growth regulators (PGR) in concentrations ranging from 0.1 to 100.0 μmol of indole-3-acetic acid, 2,4-dichlorophenoxyacetic acid (2,4-D), and kinetin (K) were added to the ASP 12-NTA solid medium (0.7% agar), and apical and intercalary segments (5 mm long) were inoculated as initial explants. K stimulated growth rates of intercalary segments of G. tenuistipitata in a linear relation, and 2,4-D (1.0 μmol) and K (10.0 μmol) stimulated growth rates of apical and intercalary segments of G. perplexa, respectively. The simultaneous formation of apical, basal, and intermediate calluses is reported for the first time in axenic tissue cultures of red algae. With intercalary segments of G. tenuistipitata, basal callus induction rates were higher than those of apical and intermediate calluses in the majority of treatments, and auxins had stimulatory effects on the formation of all callus types. In apical segments of G. perplexa, intermediate callus formation was stimulated only by treatment with 1.0 μmol of K, while apical callus formation was stimulated by indole-3-acetic acid (1.0–10.0 μmol), 2,4-D (10.0–100.0 μmol), or K (0.1 μmol). Intercalary segments of G. perplexa developed only intermediate calluses, and the majority of treatments with PGR stimulated higher rates than those presented by apical segments. Potential for regeneration (development of adventitious plantlets originated from callus cells) was higher in apical calluses than in basal and intermediate calluses developed in intercalary segments of G. tenuistipitata. Moreover, auxins and cytokinin were essential to the induction of regeneration in intermediate calluses, while specific concentrations stimulated regeneration from basal and apical calluses. Plant regeneration in G. perplexa was observed only after transferring calluses from solid to liquid medium, and the majority of treatments with PGR had stimulatory effects. Regenerating plants of G. perplexa developed tetrasporangia, and released tetraspores giving rise to adult gametophytes. Our results indicate that auxins and cytokinin have a regulatory role in the growth and morphogenesis in G. tenuistipitata and G. perplexa, and diversity of responses presented by both species is related to specific developmental systems.

The present study reports a 48-h aquatic metal-toxicity assay based on daily growth rates of the red seaweed Gracilaria domingensis (Gracilariales, Rhodophyta) in synthetic seawater. The median inhibitory concentration (IC50) for each metal cation was experimentally determined, and the ratios of free ions (aqueous complex) were calculated by software minimization of the total equilibrium activity (MINTEQA2) to determine the free median inhibitory concentration (IC50F). A model for predicting the toxicity of 14 metal cations was developed using the generic function approximation algorithm (GFA) with log IC50F values as the dependent variables and the following properties as independent variables: ionic radius (r), atomic number (AN), electronegativity (Xm), covalent index (Xm2r), first hydrolysis constant (|log KOH|), softness index (σp), ion charge (Z), ionization potential (ΔIP), electrochemical potential (ΔEo), atomic number divided by ionization potential (AN/ΔIP), and the cation polarizing power for Z2/r and Z/AR. The 3-term independent variables were predicted as the best-fit model (log IC50F: –23.64 + 5.59 Z/AR + 0.99 |log KOH| + 37.05 σp ; adjusted r2: 0.88; predicted r2: 0.68; Friedman lack-of-fit score: 1.6). This mathematical expression can be used to predict metal–biomolecule interactions, as well as the toxicity of mono-, bi-, and trivalent metal cations, which have not been experimentally tested in seaweed to date. Quantitative ion–character relationships allowed the authors to infer that the mechanism of toxicity might involve an interaction between metals and functional groups of biological species containing sulfur or oxygen. Environ Toxicol Chem 2013;32:2571–2575. © 2013 SETAC