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Goss, J. W.

Publications and source records attributed to Goss, J. W..

4 recordsLinked to original sources

Investigating lead removal at trace concentrations from water by inactive yeast cells

Traces of heavy metals found in water resources, due to mining activities and e-waste discharge, pose a global threat. Conventional treatment processes fail to remove toxic heavy metals, such as lead, from drinking water in a resource-efficient manner when their initial concentrations are low. Here, we show that by using the yeast Saccharomyces cerevisiae we can effectively remove trace lead from water via a rapid mass transfer process, achieving an uptake of up to 12 mg lead per gram of biomass in solutions with initial lead concentrations below 1 part per million. We found that the yeast cell wall plays a crucial role in this process, with its mannoproteins and {beta}-glucans being the key potential lead adsorbents. Furthermore, we discovered that biosorption is linked to a significant increase in cell wall stiffness. These findings open new opportunities for using environmentally friendly and abundant biomaterials for advanced water treatment targeting emerging contaminants. One-Sentence SummaryRemoving toxic heavy metals from water at challenging trace levels in an environmentally friendly, resource-efficient manner.

bioengineering

Microbial transformation of traditional fermented fertilizer bokashi alters chemical composition and improves plant growth

Bokashi is an organic soil amendment that makes use of microbial processes to break down agricultural waste and create a nutrient-rich fertilizer. The benefits of various types of bokashi on soil fertility and plant growth are well documented, however the changes in microbial community composition and nutrients during bokashi maturation remain poorly characterized. Here, we aimed to identify potential differences in the quality of bokashi made using different ingredients and to investigate the biochemical transformation and microbial community succession of bokashi throughout the maturation process. We compared the effects of these different types of bokashi on the growth of cucumber (Cucumis sativus) and kale (Brassica napus subsp. pabularia) seedlings, measured concentrations of NH4+ and PO43-, and characterized the bokashi bacterial and fungal communities over a 12-day maturation period. We found that cucumber and kale plants growing in all types of bokashi-amended soils exhibited increased chlorophyll levels and dry biomass. During bokashi maturation, we observed a decrease in available PO43-, and an increase in NH4+. There also appeared to be an increase in relative abundances of decomposers and beneficial microbes and a decrease in putative plant pathogens. Regardless of starting bokashi ingredients and differences in microbial composition and nutrient trends, all types of bokashi similarly improve plant growth and contain beneficial microbes.

ecology

Fission yeast polycystin Pkd2p promotes transition to cell growth during cytokinesis

Polycystins are conserved mechanosensitive channels whose mutations lead to the common human renal disorder ADPKD. Previously we discovered that the plasma membrane-localized fission yeast homologue Pkd2p is an essential protein required for cytokinesis, but the mechanism remains unclear. Here, we isolated a novel temperature-sensitive mutant pkd2-B42. Among its strong growth defects, the most unique was that many mutant cells often lost significant portion of their volume in just 5 minutes followed by a gradual recovery, a process that we termed Deflation. Unlike cell lysis, deflation did not result in the plasma membrane rupture and it occurred independently from the cell cycle progression. The tip extension of pkd2-B42 cells was 80% slower than the wild type and their turgor pressure was 50% lower. Both pkd2-B42 and the other mutant pkd2-81KD partially rescued the mutants of the yeast Hippo signaling pathway Septation Initiation Network, by preventing cell lysis, enhancing septum formation, and doubling the number of Sid2/Mob1 molecules at the spindle pole bodies. We conclude that Pkd2p promotes cell size expansion during interphase by regulating turgor pressure and antagonizes SIN during cytokinesis. Summary statementMutations of polycystins lead to human genetic disorder ADPKD. We discovered that the fission yeast homologue Pkd2p promotes the cell expansion during interphase growth and antagonizes the Hippo pathway SIN during cytokinesis.

cell biology

Characterization of the nanomechanical properties of the fission yeast (Schizosaccharomyces pombe) cell surface by atomic force microscopy

Variations in cell wall composition and biomechanical properties can contribute to the cellular plasticity required during complex processes such as polarized growth and elongation in microbial cells. This study utilizes atomic force microscopy (AFM) to map the cell surface topography of fission yeast, Schizosaccharomyces pombe, at regions of active polarized growth and to characterize the biophysical properties within these regions under physiological, hydrated conditions. High-resolution images acquired from AFM topographic scanning reveal decreased surface roughness at actively growing cell poles. Force extension curves acquired by nanoindentation probing with AFM cantilever tips under low applied force revealed increased cell wall elasticity and decreased cellular stiffness (cellular spring constant) at cell poles (17 {+/-} 4 mN/m) relative to the main body of the cell that is not undergoing growth and expansion (44 {+/-} 10 mN/m). These findings suggest that the increased elasticity and decreased stiffness at regions undergoing polarized growth at fission yeast cell poles provide the plasticity necessary for cellular extension. This is the first direct biophysical characterization of the S. pombe cell surface by AFM, and it provides a foundation for future investigation of how the surface topography and local nanomechanical properties vary during different cellular processes.

cell biology