Biology subjects

Gough, K.

Publications and source records attributed to Gough, K..

2 recordsLinked to original sources

bioRxiv2022

Modulation of the Biophysical and Biochemical Properties of Collagen by Glycation for Tissue Engineering Applications

The structural and functional properties of collagen are modulated by the presence of intramolecular and intermolecular crosslinks. Advanced Glycation End-products (AGEs) can produce intermolecular crosslinks by bonding the free amino groups of neighboring proteins. In this research, the following hypothesis is explored: The accumulation of AGEs in collagen decreases its proteolytic degradation rates while increasing its stiffness. Fluorescence Lifetime Imaging (FLIM) and Fourier-transform infrared spectroscopy (FTIR) detect biochemical changes in collagen scaffolds during the glycation process. The accumulation of AGEs increases exponentially in the collagen scaffolds as a function of Methylglyoxal (MGO) concentration by performing autofluorescence measurement and competitive ELISA. Glycated scaffolds absorb water at a much higher rate confirming the direct affinity between AGEs and interstitial water within collagen fibrils. In addition, the topology of collagen fibrils as observed by Atomic Force Microscopy (AFM) is a lot more defined following glycation. The elastic modulus of collagen fibrils decreases as a function of glycation, whereas the elastic modulus of collagen scaffolds increases. Finally, the enzymatic degradation of collagen by bacterial collagenase shows a sigmoidal pattern with a much slower degradation rate in the glycated scaffolds. This study identifies unique variations in the properties of collagen following accumulation of AGEs.

bioengineering↗

bioRxiv2021

Apoplastic effector candidates of a foliar forest pathogen trigger cell death in host and non-host plants

Forests are under threat from pests, pathogens, and changing climate. One of the major forest pathogens worldwide is Dothistroma septosporum, which causes dothistroma needle blight (DNB) of pines. D. septosporum is a hemibiotrophic fungus related to well-studied Dothideomycete pathogens, such as Cladosporium fulvum. These pathogens use small secreted proteins, termed effectors, to facilitate the infection of their hosts. The same effectors, however, can be recognised by plants carrying corresponding immune receptors, resulting in resistance responses. Hence, effectors are increasingly being exploited to identify and select disease resistance in crop species. In gymnosperms, however, such research is scarce. We predicted and investigated apoplastic D. septosporum candidate effectors (DsCEs) using bioinformatics and plant-based experiments. We discovered secreted proteins that trigger cell death in the angiosperm Nicotiana spp., suggesting their recognition by immune receptors in non-host plants. In a first for foliar forest pathogens, we also developed a novel protein infiltration method to show that tissue-cultured pine shoots can respond with a cell death response to one of our DsCEs, as well as to a reference cell death-inducing protein. These results contribute to our understanding of forest pathogens and may ultimately provide clues to disease immunity in both commercial and natural forests.

plant biology↗