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Marine pelagic mucilages (e.g., marine snow) have been reported to a greater extent than their lacustrine counterparts. A pelagic mucilage primarily comprised of chitin secretions from the invasive centric diatom, Lindavia intermedia, has been reported since the early 2000s, primarily from large, oligotrophic pre-alpine lakes of the South Island of New Zealand. To better understand the factors related to mucilage abundance, we monitored its abundance as well as factors potentially related to mucilage production over time in four mucilage-afflicted lakes. Temporal mucilage dynamics were episodic, with peaks in abundance occurring during any season, but most often during summer and autumn. Chitin was confirmed to be an important component of the mucilage, but the chitin content varied between 1 and 12% of the mucilage dry mass in the lakes. An RT-qPCR assay for chitin synthase gene overexpression in L. intermedia showed that overexpression occurred in summer and autumn, often when peaks in mucilage abundance also occurred. A correlation between mucilage and phytoplankton abundance was only observed in one of the lakes. Both dissolved reactive and total phosphorus concentrations were often below analytical detection limits in these lakes. Nitrate concentrations were also low and showed negative correlations with mucilage abundance. This suggests either that the secrection of chitinous mucilage by L. intermedia significantly depleted the available N in the water column or that mucilage facilitated N uptake by L. intermedia and/or other microorganisms associated with the mucilage. Pelagic mucilage in New Zealand lakes shares many characteristics of other conspicuous mucilage phenomena, including lake snow and marine snow. While our correlational analyses revealed some relationships and associations with mucilage abundance, the strengths of these were quite variable, indicating that as yet unstudied mucilage loss processes in these lakes (e.g., sedimentation, disintegration, decomposition, assimilation) likely also play important roles in regulating mucilage abundance.

Pectic polysaccharides from New Zealand (NZ) spinach (

The commonly occurring, high-cytotoxicity macrolide roridin E has been re-isolated from Stachybotrys chartarum and characterized by 1-D and 2-D NMR spectroscopy. Assignment of the spectral data for roridin E revealed differences from the accepted literature, and spectra are reported herein to aid in future identification. For the first time confirmation of structure was provided by a crystallographic solution for roridin E. Copyright © 2016 John WileySons, Ltd.

The future of human mesenchymal stem cells (hMSCs) as a successful cell therapy relies on bioprocessing strategies to improve the scalability of these cells without compromising their therapeutic ability. The culture-expansion of hMSCs can be enhanced by supplementation with growth factors, particularly fibroblast growth factor 2 (FGF2). The biological activity of FGF2 is controlled through interactions with heparan sulfate (HS) that facilitates ligand-receptor complex formation. We previously reported on an FGF2-interacting HS variant (termed HS2) isolated from embryonic tissue by anionic exchange chromatography that increased the proliferation and potency of hMSCs. Here, we detail the isolation of an FGF2 affinity-purified HS variant (HS8) using a scalable platform technology previously employed to generate HS variants with increased affinity for BMP-2 or VEGF