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Rotational-electric principles of RNA/DNA and viability
Get PDF: Photographic investigations of rising bubbles in seawater revealed that each bubble may
conduct a single or bi-spiraling motion, which resemble architecture of RNA or DNA respectively.
The rotational motion results from acceleration of ionic hydrates, which are separated to anionic and
cationic domains at the upper and bottom curvatures of the bubble. Afterwards, rotational motion
undergoes further acceleration in the bubble upper vortex, followed by deceleration at the vortex tip.
During that phase, the spiraling motion cause significant friction that result in polarization of
electronegative atoms of H, C, N, O and P. These may be simultaneously arranged around a whirling
cationic strands and form phosphate groups, ribose and nitrogen bases equipped with H2 and H3
rotors. It is hypothesized that such hydrogen rotors may operate as generators of electrons, which
may be detached from valence shells of electropositive atoms. Then, electrons may flow via nitrogen
bases and deoxyribose or ribose to phosphate groups. Next, the negatively charged edges of
phosphate groups may attract cationic hydrates and energize their rotational motion in the grooves,
then causing also its spiraling projection outward. That may be responsible for replication of
nucleotides and its arrangement along the cationic flow into RNA or DNA polymers, in the same
manner as originally produced by rising bubbles. Moreover, it points that hydrogen rotors may
generate energy needed for viability as well as interact with all physical and chemical fields
Live while the DNA lasts. The role of autophagy in DNA loss and survival of diploid yeast cells during chronological aging
Get PDFAging is inevitable and affects all cell types, thus yeast cells are often used as a model in aging studies. There are two approaches to studying aging in yeast: replicative aging, which describes the proliferative potential of cells, and chronological aging, which is used for studying post-mitotic cells. While analyzing the chronological lifespan (CLS) of diploid Saccharomyces cerevisiae cells, we discovered a remarkable phenomenon: ploidy reduction during aging progression. To uncover the mechanism behind this unusual process we used yeast strains undergoing a CLS assay, looking for various aging parameters. Cell mortality, regrowth ability, autophagy induction and cellular DNA content measurements indicated that during the CLS assay, dying cells lost their DNA, and only diploids survived. We demonstrated that autophagy was responsible for the gradual loss of DNA. The nucleophagy marker activation at the start of the CLS experiment correlated with the significant drop in cell viability. The activation of piecemeal microautophagy of nucleus (PMN) markers appeared to accompany the chronological aging process until the end. Our findings emphasize the significance of maintaining at least one intact copy of the genome for the survival of post-mitotic diploid cells. During chronological aging, cellular components, including DNA, are exposed to increasing stress, leading to DNA damage and fragmentation in aging cells. We propose that PMN-dependent clearance of damaged DNA from the nucleus helps prevent genome rearrangements. However, as long as one copy of the genome can be rebuilt, cells can still survive
Adaptation of the maize seedling seminal roots to drought: Essential role of plasma membrane H+-ATPases activity
Get PDFTo understand how maize plants adapt to drought, this study examines the role of plasma membrane proton pumps in root growth. is study delves into the physiological mechanisms through which maize plants respond to drought conditions, with a particular emphasis on elucidating the crucial role played by plasma membrane proton pumps in facilitating adaptive changes in root growth. Our results underscore the indispensable nature of these pumps in orchestrating precise modulation of root growth patterns during drought stress, highlighting their profound significance in stress responses. Additionally, the study reveals that osmotic stress alters lipid profiles in the plasma membrane, potentially impacting its functioning and the activity of membrane proteins. To understand the role of plasma membrane (PM) H+ -ATPases in the adaptative response to osmotic stress and in the regulation of root growth in maize, we studied the gene expression and enzyme activity of PM H+ -ATPases, as well as the changes in plant biomass and total root growth, in the seedlings of two maize cultivars: the drought-tolerant Calo cultivar and the drought-sensitive Abelardo. e seedlings were exposed to simulated drought for 24 h (treatment with 20% PEG). e enzyme activity and gene expression of the MHA4 H+ -ATPase increased in the Calo variety but declined in Abelardo plants treated with PEG. e growth of roots in Abelardo plants exposed to 24 h of PEG treatment was reduced to almost 50% of the control. Conversely, for the Calo cultivar, there was no remarkable morpho-physiological difference between the roots of stressed and non-stressed plants. erefore, the activity of the PM H+ -ATPase seems to be an important factor for proper root growth during the adaptation of maize to drought. In addition, osmotic stress also induced changes in the levels of saturated polyisoprenoid alcohols in the plasma membrane fraction of maize roots.e increased levels of this class of lipids might modulate the physico-chemical properties of the PM lipid bilayer and thus affect its functioning and modify the activity of membrane proteins, such as PM H+ -ATPase
Effect of a 3-month L-carnitine supplementation and resistance training program on circulating markers and bone mineral density in postmenopausal women: a randomized controlled trial
Get PDFA novel role for Mms2 in the control of spontaneous mutagenesis and Pol3 abundance
Get PDFMms2 is a ubiquitin E2-variant protein with a very well-documented function in the tolerance pathway that
protects both human and yeast cells from the lethal and mutagenic effects of DNA damage. Interestingly, a high
expression level of human MMS2 is associated with poor survival prognosis in different cancer diseases. Here we
have analyzed the physiological effects of Mms2 overproduction in yeast cells. We show that an increased level of
this protein causes a spontaneous mutator effect independent of Ubc13, a cognate partner of Mms2 in the PCNA-
polyubiquitinating complex responsible for the template switch. Instead, this new promutagenic role of Mms2
requires Ubc4 (E2) and two ubiquitin ligases of HECT and RING families, Rsp5 and Not4, respectively. We have
established that the promutagenic activity of Mms2 is dependent on the activities of error-prone DNA polymerase
ζ and Rev1. Additionally, it requires the ubiquitination of K164 in PCNA which facilitates recruitment of these
translesion polymerases to the replication complex. Importantly, we have established also that the cellular
abundance of Mms2 influences the cellular level of Pol3, the catalytic subunit of replicative DNA polymerase δ.
Lack of Mms2 increases the Pol3 abundance, whereas in response to Mms2 overproduction the Pol3 level de-
creases. We hypothesize that increased levels of spontaneous mutagenesis may result from the Mms2-induced
reduction in Pol3 accumulation leading to increased participation of error-prone polymerase ζ in the replica-
tion comple
Valorisation of Whey Permeate in Sequential Bioprocesses towards Value-Added Products-Optimisation of Biphasic and Classical Batch Cultures of Kluyveromyces marxianus
Get PDFWhey permeate is categorised as hazardous wastewater for aquatic environments, mainly due to its high lactose content. Therefore, it must be valorised before being released into the environment. One pathway for whey permeate management is its use in biotechnological processes. Herein, we present roads for whey permeate valorisation with the K. marxianus WUT240 strain. The established technology is based on two bioprocesses. During first, 2.5 g/L 2-phenylethanol and fermented plant oils enriched with different flavourings are obtained after 48 h biphasic cultures at 30 °C. The second process leads to a maximum of 75 g ethanol/L (YP/S = 0.53 g/g) after 96 h at 30 °C. Moreover, established whey permeate valorisation pathways reduced its biochemical oxygen demand and chemical oxygen demand values by 12- to 3-fold, respectively. Together, the present study reports a complete, effective, and environmentally friendly whey permeate management strategy while simultaneously enabling the acquisition of valuable compounds with substantial application potential
A Dhdds K42E knock-in RP59 mouse model shows inner retina pathology and defective synaptic transmission
Get PDFRetinitis pigmentosa (RP) defines a group of hereditary progressive rod-cone degenerations that exhibit a common phenotype caused by variants in over 70 genes. While most variants in the dehydrodolichyl diphosphate synthase (DHDDS) gene result in syndromic abnormalities, some variants cause non-syndromic RP (RP59). DHDDS encodes one subunit of the enzyme cisprenyltransferase (CPT), which is required for the synthesis of dolichol (Dol), that is a necessary protein glycosylation cofactor. We previously reported the creation and initial characterization of a knock-in (KI) mouse model harboring the most prevalent RP59-associated DHDDS variant (K42E) to understand how defects in DHDDS lead to retina-specific pathology. This model exhibited no profound retinal degeneration, nor protein N-glycosylation defects. Here, we report that the Dol isoprenylogue species in retina, liver, and brain of the K42E mouse model are statistically shorter than in the corresponding tissues of age-matched controls, as reported in blood and urine of RP59 patients. Retinal transcriptome analysis demonstrated elevation of many genes encoding proteins involved in synaptogenesis and synaptic function. Quantitative retinal cell layer thickness measurements demonstrated a significant reduction in the inner nuclear layer (INL) and total retinal thickness (TRT) beginning at postnatal (PN) ∼2 months, progressively increasing to PN 18-mo. Histological analysis revealed cell loss in the INL, outer plexiform layer (OPL) disruption, and
ectopic localization of outer nuclear layer (ONL) nuclei into the OPL of K42E mutant retinas, relative to controls. Electroretinograms (ERGs) of mutant mice exhibited reduced b-wave amplitudes beginning at PN 1-mo, progressively declining through PN 18-mo,without appreciable a-wave attenuation, relative to controls. Our results suggest that the underlying cause of DHDDS K42E variant driven RP59 retinal pathology is defective synaptic transmission from outer to inner retina
Genomy mitochondrialne – jedność i różnorodność
Get PDFPowstanie mitochondriów było jednym z najważniejszych wydarzeń w historii życia na Ziemi. Wchłonięta komórka bakteryjna, przekształcona następnie w mitochondrium zachowała swój genom, który uległ następnie licznym modyfikacjom. Na skutek masowej utraty i licznych transferów genów do genomu jądrowego autonomiczna bakteria uległa ostatecznie przekształceniu w organellum, które znamy dzisiaj. W efekcie zmian zachodzących niezależnie w różnych liniach ewolucyjnych obserwujemy bardzo dużą różnorodność genomów mitochondrialnych na poziomie struktury jak i pod względem zawartości genów. W większości przypadków mitochondrialny DNA zachował kolisty kształt, nie jest to jednak jedyna jego obserwowana forma – w mitochondriach niektórych eukariontów obserwujemy cząsteczki liniowe, a w skrajnych przypadkach, w zredukowanych organellach pochodzenia mitochondrialnego, genom został całkowicie utracony. W niniejszym artykule omawiamy różnorodność struktur genomów mitochondrialnych w obrębie największych grup Eukarya
Cold adapted and closely related mucoraceae species colonise dry-aged beef (DAB)
Get PDFThe dry ageing is a historically relevant method of meat preservation, now used as a way to produce the dry-aged beef (DAB) known for its pronounced flavour. Partially responsible for the taste of the DAB may be various microorganisms that grow on the surface of the meat. Historically, the fungal species colonising the DAB were described as members of the genera Thamnidium and Mucor. In this study we used both culture based approach as well as ITS2 rDNA metabarcoding analysis to investigate the fungal community of the DAB, with special emphasis on the mucoralean taxa. Isolated fungi were members of 6 different species from the family Mucoraceae, belonging to the genera Mucor and Helicostylum. Metabarcoding data provided supplementary information regarding the presence of other fungi including those from the Thamnidium genus. In both approaches used in this study isolates closely related to the Mucor flavus strain CBS 992.68 dominated. © 2023 The Author
Genomic and transcriptomic analysis of Ligilactobacillus salivarius IBB3154—in search of new promoters for vaccine construction
No full textTranscriptomic analysis of the genome sequenced Ligilactobacillus salivarius strain IBB3154 grown at two different temperatures (37°C vs 42°C) identified differentially expressed genes involved in metabolic pathways, osmoregulation, and surface protein expression. Two highly expressed genes, sasA1 and sasA2, which encode cell wall-anchored proteins belonging to the serine-rich repeat protein group, were found to be temperature-inducible. Moonlighting proteins with various functions, such as glyceraldehyde 3-phosphate dehydrogenase, fructose-bisphosphate aldolase, elongation factor Tu, and enolase, were highly expressed at both temperatures. The efficiency of promoters has been confirmed by the β-glucuronidase activity test; however, temperature dependence was not detected. We also found that the P sasA1 promoter retained its activity in the presence of bile salts. Knowledge of promoters that are highly active in L. salivarius cells can be used to produce strains that are carriers of immunogenic proteins