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Current Opinion in Plant Biology Feb 2017Two major conducting tissues in plants, phloem and xylem, are composed of highly specialized cell types adapted to long distance transport. Sieve elements (SEs) in the... (Review)
Review
Two major conducting tissues in plants, phloem and xylem, are composed of highly specialized cell types adapted to long distance transport. Sieve elements (SEs) in the phloem display a thick cell wall, callose-rich sieve plates and low cytoplasmic density. SE differentiation is driven by selective autolysis combined with enucleation, after which the plasma membrane and some organelles are retained. By contrast, differentiation of xylem tracheary elements (TEs) involves complete clearance of the cellular components by programmed cell death followed by autolysis of the protoplast; this is accompanied by extensive deposition of lignin and cellulose in the cell wall. Emerging molecular data on TE and SE differentiation indicate a central role for NAC and MYB type transcription factors in both processes.
Topics: Arabidopsis; Arabidopsis Proteins; Cell Differentiation; Phloem; Plant Development; Plant Proteins; Transcription Factors; Xylem
PubMed: 27794261
DOI: 10.1016/j.pbi.2016.10.007 -
Food Research International (Ottawa,... Feb 2023Animal aquatic products have high water content, abundant enzyme system and their own diverse microbial flora. These products are severely susceptible to autolysis and... (Review)
Review
Animal aquatic products have high water content, abundant enzyme system and their own diverse microbial flora. These products are severely susceptible to autolysis and degradation after death, resulting in many adverse effects on storage, processing, and transportation. Among them, the endogenous enzyme are the key factor that caused the autolysis and degradation. Autolytic hydrolysis provides an effective way to maximize the use of aquatic by-products and achieve increased protein resources and reduce environmental pollution from by-products. To better acquaintance the autolysis phenomenon and regulation of the autolysis phenomenon. This paper reviews the autolytic mechanism, biochemical changes, influencing factors, and potential applications of animal aquatic products and their by-products to explore autolysis and its effective utilization and regulation. In addition, this study also emphasizes the importance of making full use of aquatic by-products. Furthermore, the research trends and future challenges of autolysis are also discussed. Autolysis can effectively transform aquatic products and by-products into bioactive hydrolysates. The hydrolysates produced by the autolysis of aquatic products and their by-products have attracted attention because of their wide applications in food, healthcare, and animal feed industries. However, the mechanism and regulation (promotion or inhibition) of autolysis should be further studied, and autolysate at the industrial level should be produced to provide high-value-added products for by-product processing and realize the sustainable utilization of resources.
Topics: Animals; Proteins; Environmental Pollution; Hydrolysis
PubMed: 36737919
DOI: 10.1016/j.foodres.2022.112325 -
Frontiers in Microbiology 2023
PubMed: 37234522
DOI: 10.3389/fmicb.2023.1199578 -
International Journal of Antimicrobial... Oct 2023The pathogenicity of Staphylococcus epidermidis is largely attributed to its exceptional ability to form biofilms. Here, we report that mupirocin, an antimicrobial agent...
The pathogenicity of Staphylococcus epidermidis is largely attributed to its exceptional ability to form biofilms. Here, we report that mupirocin, an antimicrobial agent widely used for staphylococcal decolonization and anti-infection, strongly stimulates the biofilm formation of S. epidermidis. Although the polysaccharide intercellular adhesin (PIA) production was unaffected, mupirocin significantly facilitated extracellular DNA (eDNA) release by accelerating autolysis, thereby positively triggering cell surface attachment and intercellular agglomeration during biofilm development. Mechanistically, mupirocin regulated the expression of genes encoding for the autolysin AtlE as well as the programmed cell death system CidA-LrgAB. Critically, through gene knockout, we found out that deletion of atlE, but not cidA or lrgA, abolished the enhancement of biofilm formation and eDNA release in response to mupirocin treatment, indicating that atlE is required for this effect. In Triton X-100 induced autolysis assay, mupirocin treated atlE mutant displayed a slower autolysis rate compared with the wild-type strain and complementary strain. Therefore, we concluded that subinhibitory concentrations of mupirocin enhance the biofilm formation of S. epidermidis in an atlE dependent manner. This induction effect could conceivably be responsible for some of the more unfavourable outcomes of infectious diseases.
Topics: Staphylococcus epidermidis; Mupirocin; Biofilms; Staphylococcus; Virulence; Bacterial Proteins
PubMed: 37385560
DOI: 10.1016/j.ijantimicag.2023.106904 -
FASEB Journal : Official Publication of... Feb 2021Serine proteases are a large family of enzymes critical for multiple physiological processes, and proven diagnostic and therapeutic targets in several clinical... (Review)
Review
Serine proteases are a large family of enzymes critical for multiple physiological processes, and proven diagnostic and therapeutic targets in several clinical indications. The high similarity of active sites among different serine proteases posts a challenge to reach high selectivity for inhibitors of serine proteases targeting at the active site. Here, we demonstrated that one particular surface loop on serine proteases (autolysis loop) can be used to regulate their catalytic activity, through surveying the recent works including ours, and such an approach can reach high specificity. The autolysis loop is highly variable among different serine proteases, explaining the high specificity of inhibitors targeting the autolysis loop. We also outline the structural origin that links the perturbation of the autolysis loop and the inhibition of protease activity. Thus, the autolysis loop appears to be a highly sensitive allosteric site and can be used as a general handle to develop pharmacological agents to intervene with the activities of serine proteases in, eg, blood coagulation.
Topics: Animals; Catalytic Domain; Enzyme Stability; Humans; Proteolysis; Serine Proteases; Serine Proteinase Inhibitors
PubMed: 33417271
DOI: 10.1096/fj.202002139RR -
Current Pharmaceutical Design 2017Drug concentrations obtained from post mortem samples do not necessarily reflect the concentrations at the time of death, and variations of concentration may be observed... (Review)
Review
BACKGROUND
Drug concentrations obtained from post mortem samples do not necessarily reflect the concentrations at the time of death, and variations of concentration may be observed between different sites and/or different sampling times. These phenomena, collectively termed post mortem redistribution, concern numerous molecules (medications, drugs of abuse, gases, etc.) and can complicate the interpretation of toxicological analyses.
METHODS
Literature review.
RESULTS
The mechanisms that cause these phenomena are complex and often intricate. Certain organs, which concentrate the molecules before death, may release them very early in the vascular sector. The gastrointestinal tract, liver, lungs and myocardium are mainly concerned. Cell autolysis also plays a part in drug release. Furthermore, micro-organisms (mainly bacteria and yeasts) which colonize the organism during putrefaction may cause neoformation and/or the degradation of certain molecules. Lastly, it appears that the physicochemical and pharmacokinetic profile of xenobiotics, notably their lipophilic nature, their ionization state and their volume of distribution may be factors likely to influence redistribution phenomena. Some recommendations concerning anatomic sampling sites, sampling methods and sample storage make it possible to limit these phenomena.
Topics: Autolysis; Humans; Lipid Metabolism; Pharmaceutical Preparations; Postmortem Changes; Substance Abuse Detection; Tissue Distribution
PubMed: 28641544
DOI: 10.2174/1381612823666170622111739 -
Romanian Journal of Morphology and... 2019Blaise Pascal (1623-1662) was a French philosopher, who wrote the Pensées, a collection of "thoughts" about the apparent insignificance of human existence. In the last... (Review)
Review
Blaise Pascal (1623-1662) was a French philosopher, who wrote the Pensées, a collection of "thoughts" about the apparent insignificance of human existence. In the last three centuries, it was claimed that his disease was mental. Hysteria, melancholia, and post-traumatic neurosis were taken into consideration, but none of the proposed diagnoses seems to be satisfactory. The aim of our work is to identify Pascal's mysterious illness. We correlated the symptoms of the indirect anamnesis (Pascal's letters to friends, letters and biographies made by his sisters and granddaughter) and autopsy data. Based on these data, we consider that Pascal's illness, which has affected him all his life and caused his death, was celiac disease, the diagnosis being supported by: childhood abdominal pain with gradual progression to neurological manifestations in his middle-age, which were expressed by migraine-type headaches, peripheral neuropathy, epilepsy, neuropsychiatric disorders (depression). The hypothesis of a celiac disease is also argued by autopsy data: lack of closure of the fontanelle due to type D hypovitaminosis, intestinal gangrene because celiac disease accelerates the post-mortem autolysis, gliosis and calcification of the nervous tissue. The second cause of his death was a chronic traumatic subdural hematoma, probably located in the superior temporal region, which was the reason for his left-sided hemianopsia that occurred immediately after a carriage accident. Conclusions: Pascal's philosophy reflects his own inner life, which was deeply influenced by the organic affections he suffered.
Topics: History, 17th Century; Humans; Mental Disorders; Philosophy
PubMed: 32239123
DOI: No ID Found -
Scientific Reports Jul 2021Kluyveromyces marxianus is a yeast that could be identified from kefir and can use a broad range of substrates, such as glucose and lactate, as carbon sources. The...
Kluyveromyces marxianus is a yeast that could be identified from kefir and can use a broad range of substrates, such as glucose and lactate, as carbon sources. The lactate produced in kefir culture can be a substrate for K. marxianus. However, the complexity of the kefir microbiota makes the traits of K. marxianus difficult to study. In this research, we focused on K. marxianus cultured with lactate as the sole carbon source. The optimal growth and released protein in lactate culture were determined under different pH conditions, and the LC-MS/MS-identified proteins were associated with the tricarboxylic acid cycle, glycolysis pathway, and cellular stress responses in cells, indicating that autolysis of K. marxianus had occurred under the culture conditions. The abundant glyceraldehyde-3-phosphate dehydrogenase 1 (GAP1) was cocrystallized with other proteins in the cell-free fraction, and the low transcription level of the GAP1 gene indicated that the protein abundance under autolysis conditions was dependent on protein stability. These results suggest that lactate induces the growth and autolysis of K. marxianus, releasing proteins and peptides. These findings can be fundamental for K. marxianus probiotic and kefir studies in the future.
Topics: Culture Media; Electrophoresis, Polyacrylamide Gel; Fungal Proteins; Gene Expression Regulation, Fungal; Hydrogen-Ion Concentration; Kefir; Kluyveromyces; Lactic Acid; Multilocus Sequence Typing; Mycological Typing Techniques; Tandem Mass Spectrometry
PubMed: 34267270
DOI: 10.1038/s41598-021-94101-y -
Nature Communications Feb 2024Traditional histochemical staining of post-mortem samples often confronts inferior staining quality due to autolysis caused by delayed fixation of cadaver tissue, and...
Traditional histochemical staining of post-mortem samples often confronts inferior staining quality due to autolysis caused by delayed fixation of cadaver tissue, and such chemical staining procedures covering large tissue areas demand substantial labor, cost and time. Here, we demonstrate virtual staining of autopsy tissue using a trained neural network to rapidly transform autofluorescence images of label-free autopsy tissue sections into brightfield equivalent images, matching hematoxylin and eosin (H&E) stained versions of the same samples. The trained model can effectively accentuate nuclear, cytoplasmic and extracellular features in new autopsy tissue samples that experienced severe autolysis, such as COVID-19 samples never seen before, where the traditional histochemical staining fails to provide consistent staining quality. This virtual autopsy staining technique provides a rapid and resource-efficient solution to generate artifact-free H&E stains despite severe autolysis and cell death, also reducing labor, cost and infrastructure requirements associated with the standard histochemical staining.
Topics: Hematoxylin; Eosine Yellowish-(YS); Staining and Labeling; Neural Networks, Computer
PubMed: 38396004
DOI: 10.1038/s41467-024-46077-2 -
The Biochemical Journal Jul 2020The Dispase autolysis-inducing protein (DAIP) from Streptomyces mobaraensis attracts M4 metalloproteases, which results in inhibition and autolysis of bacillolysin (BL)...
The Dispase autolysis-inducing protein (DAIP) from Streptomyces mobaraensis attracts M4 metalloproteases, which results in inhibition and autolysis of bacillolysin (BL) and thermolysin (TL). The present study shows that aureolysin (AL) from Staphylococcus aureus and pseudolysin (LasB) from Pseudomonas aeruginosa are likewise impaired by DAIP. Complete inhibition occurred when DAIP significantly exceeded the amount of the target protease. At low DAIP concentrations, AL and BL performed autolysis, while LasB and TL degradation required reductants or detergents that break intramolecular disulfide bonds or change the protein structure. Site directed mutagenesis of DAIP and removal of an exposed protein loop either influenced binding or inhibition of AL and TL but had no effect on LasB and BL. The Y170A and Δ239-248 variants had completely lost affinity for TL and AL. The exchange of Asn-275 also impaired the interaction of DAIP with AL. In contrast, DAIP Phe-297 substitution abolished inhibition and autolysis of both target proteases but still allowed complex formation. Our results give rise to the conclusion that other, yet unknown DAIP amino acids inactivate LasB and BL. Obviously, various bacteria in the same habitat caused Streptomyces mobaraensis to continuously optimize DAIP in inactivating the tackling metalloproteases.
Topics: Amino Acids; Autolysis; Bacterial Proteins; Calorimetry; Chromatography, Gel; Circular Dichroism; Endopeptidases; Metalloendopeptidases; Metalloproteases; Staphylococcus aureus
PubMed: 32602533
DOI: 10.1042/BCJ20200407