Synthetic, Photophysical, and Catalytic Studies of Light-Harvesting Macrocyclic Complexes

Chromophores are an important class of compounds in Nature and industry, with several hundred thousand tons produced annually as dyes and pigments. Alone, these compounds absorb light unto themselves; however, several of these compounds can be combined to produce a beneficial cascading transfer of energy to a core chromophore. In this study, photophysical properties of several covalent and axially borondipyrromethene (BODIPY)-conjugated complexes of porphyrin and salphen scaffolds have been evaluated in a series of emission and catalytic studies. In the porphyrin systems, a beneficial excited energy transfer (EET) from the BODIPY moieties to the porphyrin core was observed; however, only the covalently bound BODIPY metal complexes displayed enhanced activity in the catalytic oxidation reactions in the presence of visible light. The BODIPY-porphyrin ligand displayed fluorescence quenching when excited at the porphyrin or BODIPY moieties roughly equal to 50% of the bare tetra(phenyl)porphyrin (TPP) ligand which indicated an efficient EET from the BODIPY-antennae to the porphyrin core. The axially BODIPY-porphyrin iron(III) complex displayed an intense green fluorescence corresponding to the BODIPY moiety due to an electron transfer from the phenolate ligand to the porphyrin core completely quenching the porphyrin emission. The BODIPY-salphen (L-Salphen) conjugates displayed the opposite EET compared to the porphyrin conjugates, instead transferring energy away from the salphen core to the BODIPY-moieties. A beneficial light effect was observed with the chromium L-Salphen complex; however, the effect was deemed to be the cause of visible light irradiation’s ability to destabilize the meta-stable chromium-oxo bond rather than an EET of the BODIPY-moieties to salphen core. In addition, several iron(III) phthalocyanine complexes [FeIII(Pc)Cl] were synthesized and evaluated in the catalytic oxidation of thioanisoles to compare their viability to previous metalloporphyrin systems. The [FeIII(Pc)Cl] catalysts gave quantitative conversions of the starting sulfides with moderate to excellent selectivity towards sulfoxide over sulfone but displayed an unexpected sustainability towards oxidative degradation even with mild terminal oxidants, i.e., iodobenzene diacetate [PhI(OAc)2]. Nonetheless, efforts were made to probe the active oxospecies with PhI(OAc)2, and a putative iron(IV)-oxo radical cation was spectroscopically observed in the systems of unsubstituted phthalocyanine [H2(Pc)] and the 1,4,5,8,9,12,13,16-(a)- octabutyloxyphthalocyanine [H2(α-(OBu)8-Pc)] ligands

The global meningitis genome partnership

GGenomic surveillance of bacterial meningitis pathogens is essential for effective disease control globally, enabling identification of emerging and expanding strains and consequent public health interventions. While there has been a rise in the use of whole genome sequencing, this has been driven predominately by a subset of countries with adequate capacity and resources. Global capacity to participate in surveillance needs to be expanded, particularly in low and middle-income countries with high disease burdens. In light of this, the WHO-led collaboration, Defeating Meningitis by 2030 Global Roadmap, has called for the establishment of a Global Meningitis Genome Partnership that links resources for: N. meningitidis (Nm), S. pneumoniae (Sp), H. influenzae (Hi) and S. agalactiae (Sa) to improve worldwide co-ordination of strain identification and tracking. Existing platforms containing relevant genomes include: PubMLST: Nm (31,622), Sp (15,132), Hi (1935), Sa (9026); The Wellcome Sanger Institute: Nm (13,711), Sp (> 24,000), Sa (6200), Hi (1738); and BMGAP: Nm (8785), Hi (2030). A steering group is being established to coordinate the initiative and encourage high-quality data curation. Next steps include: developing guidelines on open-access sharing of genomic data; defining a core set of metadata; and facilitating development of user-friendly interfaces that represent publicly available data

The global meningitis genome partnership.

Genomic surveillance of bacterial meningitis pathogens is essential for effective disease control globally, enabling identification of emerging and expanding strains and consequent public health interventions. While there has been a rise in the use of whole genome sequencing, this has been driven predominately by a subset of countries with adequate capacity and resources. Global capacity to participate in surveillance needs to be expanded, particularly in low and middle-income countries with high disease burdens. In light of this, the WHO-led collaboration, Defeating Meningitis by 2030 Global Roadmap, has called for the establishment of a Global Meningitis Genome Partnership that links resources for: N. meningitidis (Nm), S. pneumoniae (Sp), H. influenzae (Hi) and S. agalactiae (Sa) to improve worldwide co-ordination of strain identification and tracking. Existing platforms containing relevant genomes include: PubMLST: Nm (31,622), Sp (15,132), Hi (1935), Sa (9026); The Wellcome Sanger Institute: Nm (13,711), Sp (> 24,000), Sa (6200), Hi (1738); and BMGAP: Nm (8785), Hi (2030). A steering group is being established to coordinate the initiative and encourage high-quality data curation. Next steps include: developing guidelines on open-access sharing of genomic data; defining a core set of metadata; and facilitating development of user-friendly interfaces that represent publicly available data

The Terebridae and teretoxins: Combining phylogeny and anatomy for concerted discovery of bioactive compounds

The Conoidea superfamily, comprised of cone snails, terebrids, and turrids, is an exceptionally promising group for the discovery of natural peptide toxins. The potential of conoidean toxins has been realized with the distribution of the first Conus (cone snail) drug, Prialt (ziconotide), an analgesic used to alleviate chronic pain in HIV and cancer patients. Cone snail toxins (conotoxins) are highly variable, a consequence of a high mutation rate associated to duplication events and positive selection. As Conus and terebrids diverged in the early Paleocene, the toxins from terebrids (teretoxins) may demonstrate highly divergent and unique functionalities. Recent analyses of the Terebridae, a largely distributed family with more than 300 described species, indicate they have evolutionary and pharmacological potential. Based on a three gene (COI, 12S and 16S) molecular phylogeny, including ~50 species from the West-Pacific, five main terebrid lineages were discriminated: two of these lineages independently lost their venom apparatus, and one venomous lineage was previously unknown. Knowing the phylogenetic relationships within the Terebridae aids in effectively targeting divergent lineages with novel peptide toxins. Preliminary results indicate that teretoxins are similar in structure and composition to conotoxins, suggesting teretoxins are an attractive line of research to discover and develop new therapeutics that target ion channels and receptors. Using conotoxins as a guideline, and innovative natural products discovery strategies, such as the Concerted Discovery Strategy, the potential of the Terebridae and their toxins are explored as a pioneering pharmacological resource