Background: Candida glabrata virulence is poorly understood at the molecular level.Results: Inactivation of components of the C. glabrata glycosylation machinery results in changes in fungal mannan structure and altered virulence.Conclusion: Changes in C. glabrata cell wall architecture impact the host-pathogen interactions.Significance: Greater understanding of C. glabrata virulence will provide insights that can be adopted for development of novel diagnostic and therapeutic interventions.

β-glucan is a (1→3)-β-linked glucose polymer with (1→6)-β-linked side chains and a major component of fungal cell walls. β-glucans provide structural integrity to the fungal cell wall. The nature of the (1–6)-β-linked side chain structure of fungal (1→3,1→6)-β-D-glucans has been very difficult to elucidate. Herein, we report the first detailed structural characterization of the (1→6)-β-linked side chains of Candida glabrata using high-field NMR. The (1→6)-β-linked side chains have an average length of 4 to 5 repeat units spaced every 21 repeat units along the (1→3)-linked polymer backbone. Computer modeling suggests that the side chains have a bent curve structure that allows for a flexible interconnection with parallel (1→3)-β-D-glucan polymers, and/or as a point of attachment for proteins. Based on these observations we propose new approaches to how (1→6)-β-linked side chains interconnect with neighboring glucan polymers in a manner that maximizes fungal cell wall strength, while also allowing for flexibility, or plasticity.

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Stereochemical control of spiropyran ring-closure was explored through synthesis of sterically-congested spiropyrans by a novel, efficient method.

The synthesis of bidentate N/O 1,1‘-ferrocenediyl analogues of N-aryl-salicylaldimines has been accomplished from the previously unreported 1‘-hydroxyferrocenecarbaldehyde, 3. Thus, the reaction of 3 with 2,6-diisopropylaniline and with aniline leads to the isolation of N-(2,6-diisopropylphenyl)-(1‘-(hydroxy)ferrocenyl)aldimine, 5, and N-phenyl-(1‘-(hydroxy)ferrocenyl)aldimine, 6, respectively. However, attempts to synthesize analogues of bis(iminophenoxide) (salen) ligands by treatment of 3 with 1,2-ethylenediamine and with trans-(+/−)-1,2-diaminocyclohexane led to intractable product mixtures, while reaction with 1,2-phenylenediamine resulted in formation of a substituted benzimidazole. Titanium bis(isopropoxide) complexes of 5, 6, and, for comparative purposes, 1‘-(diphenylphosphino)hydroxyferrocene have been synthesized, and in a preliminary study all three complexes were found to initiate the ring-opening polymerization of rac-lactide in a well-controlled manner.