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Finding ways to isolate anions and metals is a modern problem as concerns over pollution of anions have become popular in the scientific community. The applications of supramolecular structures are endless, ranging from drug delivery to refining metals at an industrial scale. In this thesis, three variations of a di-salicylaldimine linked ligands were designed to form anion encapsulating mesocates. Each ligand differs by the spacer linking the salicylaldimine units. L1 has a six-carbon spacer, L2 has a p-xylylic spacer and L3 has a m-xylylic spacer. After the synthesis and characterisation of these ligands, complexation was achieved with various nickel salts resulting in the formation of dinuclear triple-stranded mesocate complexes; [BF₄⊂Ni₂(L1)₃](BF₄)₃ (C1), [ClO₄⊂Ni₂(L1)₃](ClO₄)₃ (C2) and two dinuclear di-stranded mesocate complexes; [SO₄⊂Ni₂(L3)₂][Ni(SO₄)₂ (EtOH)₄] (C3), [ClO₄⊂Ni₂(L3)₂](ClO₄)₂ (C4). The crystals have been characterised with IR spectroscopy, UV-Vis spectroscopy, mass spectrometry, atomic absorption spectroscopy, conductivity measurements and single crystal X-ray diffraction. An uncommon mesocate structure was observed from the X-ray diffraction data collected whereby the anion in the centre of the cage forms covalent bonds with the two Ni²⁺ metal ions. In addition, metal salt extraction experiments were attempted in a two-phase solvent system with L3, nickel sulfate to assess how much nickel and sulfate could be extracted from the aqueous mixture to the organic solution. Although a reliable measurement of sulfate could not be obtained, the highest percentage of the nickel extracted measured in hexane was 89%. However, there is potential to gather a higher value using the optimal conditions found in these experiments.

Cuscuta spp. are obligate parasites that connect to host vascular tissue using a haustorium. In addition to water, nutrients, and metabolites, a large number of mRNAs are bidirectionally exchanged between Cuscuta spp. and their hosts. This trans-specific movement of mRNAs raises questions about whether these molecules function in the recipient species. To address the possibility that mobile mRNAs are ultimately translated, we built upon recent studies that demonstrate a role for transfer RNA (tRNA)-like structures (TLSs) in enhancing mRNA systemic movement. C. campestris was grown on Arabidopsis that expressed a β-glucuronidase (GUS) reporter transgene either alone or in GUS-tRNA fusions. Histochemical staining revealed localization in tissue of C. campestris grown on Arabidopsis with GUS-tRNA fusions, but not in C. campestris grown on Arabidopsis with GUS alone. This corresponded with detection of GUS transcripts in Cuscuta on Arabidopsis with GUS-tRNA, but not in C. campestris on Arabidopsis with GUS alone. Similar results were obtained with Arabidopsis host plants expressing the same constructs containing an endoplasmic reticulum localization signal. In C. campestris, GUS activity was localized in the companion cells or phloem parenchyma cells adjacent to sieve tubes. We conclude that host-derived GUS mRNAs are translated in C. campestris and that the TLS fusion enhances RNA mobility in the host-parasite interactions.

Parasitic weeds represent a major threat to agricultural production across the world. Little is known about which host genetic pathways determine compatibility for any host-parasitic plant interaction. We developed a quantitative assay to characterize the growth of the parasitic weed Phelipanche aegyptiaca on 46 mutant lines of the host plant Arabidopsis thaliana to identify host genes that are essential for susceptibility to the parasite. A. thaliana host plants with mutations in genes involved in jasmonic acid biosynthesis/signaling or the negative regulation of plant immunity were less susceptible to P. aegyptiaca parasitization. In contrast, A. thaliana plants with a mutant allele of the putative immunity hub gene Pfd6 were more susceptible to parasitization. Additionally, quantitative PCR revealed that P. aegyptiaca parasitization leads to transcriptional reprograming of several hormone signaling pathways. While most tested A. thaliana lines were fully susceptible to P. aegyptiaca parasitization, this work revealed several host genes essential for full susceptibility or resistance to parasitism. Altering these pathways may be a viable approach for limiting host plant susceptibility to parasitism.