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Biazik, J.

Publications and source records attributed to Biazik, J..

3 recordsLinked to original sources

Bacterial Decellularization: Non-Chemical Production of Effective Plant Tissue Bio-Scaffolds

Bio-scaffolds for the cellular agriculture field require to be simple, with low associated costs. Here, a method is described to generate decellularized leaf scaffolds utilizing a simple bacterial process, yielding scaffolds with the capacity to sustain myoblast attachment, growth, and differentiation. To best develop a minimal cost decellularization process, we aimed to design the key steps of the method to be as "low-tech" as possible and not use chemical or thermal processing to produce the cellular scaffold. Decellularized leaves (DCL) from the black walnut tree (Juglans nigra) were successfully produced employing a domestic fish tank with a biological filtration system that supports an active aquatic nitrogen-fixing bacterial population, typically within 3-5 days. Following decellularization, the DCL were devoid of any pulp material as confirmed by scanning electron microscopy (SEM). DCL produced in this way are an effective cellular scaffold, and the C2C12 myoblast cell line was shown to attach, proliferate and differentiate on DCL and maintain viability up to 3 weeks post-seeding. Differentiated cellular material grew extensively over the DCL veins and larger differentiated cellular structures extended between individual DCL veins. The data presented provide a proof of concept for an inexpensive, simple, and chemical-free method for leaf decellularization, which supports myoblast attachment, growth, and differentiation. The technology provides clear applications for the cellular agriculture field where cost reduction, scalability, and simplification of established laboratory processes, such as bio scaffold production, is a key factor.

bioengineering↗

Molecular dissection of the soluble photosynthetic antenna from a cryptophyte alga

Cryptophyte algae have a unique phycobiliprotein light-harvesting antenna that fills a spectral gap in chlorophyll absorption, however, it is unclear how it transfers energy efficiently to photosystems. We show that the cryptophyte Hemiselmis andersenii expresses an energetically complex antenna comprising three distinct spectrotypes of phycobiliprotein with different quaternary structures arising from a diverse subunit family. The bulk of the antenna consists of open quaternary form phycobiliproteins acting as primary photon acceptors, supplemented by novel open-braced forms. The final components are closed forms with a long wavelength spectral feature due to substitution of a single chromophore. We propose that the macromolecular organization of the cryptophyte antennas consists of bulk open and open-braced forms that transfer excitations to photosystems via this bridging closed form phycobiliprotein. One-Sentence SummaryAlgae generate a rainbow of antenna proteins by combining a conserved subunit with different members of a multigene family.

molecular biology↗

Oocyte and cumulus cell cooperativity and metabolic plasticity under the direction of oocyte paracrine factors

Mammalian oocytes develop and mature in a mutually dependent relationship with surrounding cumulus cells. The oocyte actively regulates cumulus cell differentiation and function by secreting soluble paracrine oocyte-secreted factors (OSFs). We characterized the molecular mechanisms by which two model OSFs, cumulin and BMP15, regulate oocyte maturation and cumulus-oocyte cooperativity. Exposure to these OSFs during maturation altered the proteomic and multispectral autofluorescence profiles of both the oocyte and cumulus cells. In oocytes, cumulin significantly upregulated proteins involved in nuclear function. In cumulus cells, both OSFs elicited marked upregulation of a variety of metabolic processes (mostly anabolic), including lipid, nucleotide, and carbohydrate metabolism, while mitochondrial metabolic processes were downregulated. The mitochondrial changes were validated by functional assays confirming altered mitochondrial morphology, respiration, and content, whilst maintaining ATP homeostasis. Collectively, these data demonstrate that OSFs remodel cumulus cell metabolism during oocyte maturation in preparation for ensuing fertilization and embryonic development. HIGHLIGHTSO_LIDuring oocyte maturation, oocyte-secreted factors promote cell cooperativity between the oocyte and cumulus cells by altering the molecular composition of both cell types. C_LIO_LIOocyte-secreted factors downregulate protein catabolic processes, and upregulate DNA binding, translation, and ribosome assembly in oocytes. C_LIO_LIOocyte-secreted factors alter mitochondrial number, morphology, and function in cumulus cells. C_LIO_LIOocyte-secreted factors further enhance metabolic plasticity in cumulus cells by upregulating anabolic pathways for macromolecules and small molecule organics. C_LIO_LIThe oocyte, via oocyte-secreted factors, instructs cumulus cells to increase metabolic workload on its behalf, thereby subduing oocyte metabolism. C_LI

developmental biology↗