Yeast autolysis affects the flavor and quality of beer. The regulation of yeast autolysis is a need for industrial beer production. Previous studies on brewer's yeast autolysis showed that the citric acid cycle-related genes had a great influence on yeast autolysis. To explore the contribution of isocitrate dehydrogenase genes in autolysis, the IDP1 and IDP2 genes were destroyed or overexpressed in typical lager yeast Pilsner. The destruction of IDP1 gene improved the anti-autolytic ability of yeast, and the anti-autolytic index after 96 h autolysis was 8.40, 1.5 times higher than that of the original strain. The destruction of IDP1 gene increased the supply of nicotinamide adenine dinucleotide phosphate (NADPH) and the NADPH/NADP⁺ ratio was 1.94. After fermentation, intracellular ATP level was 1.8 times higher than that of the original strain, while reactive oxygen species (ROS) was reduced by 10%. The destruction of IDP2 gene resulted in rapid autolysis and a decrease in the supply of NADPH. Anti-autolytic index after 96 h autolysis was 4.03 and the NADPH/NADP⁺ ratio was 0.89. After fermentation, intracellular ATP level was reduced by 8% compared with original strain, ROS was 1.3 times higher than that of the original strain. The results may help understand the regulation mechanism of citric acid cycle-related genes on yeast autolysis and provide a basis for the selection of excellent yeast with controllable anti-autolytic performance.
Humans ; Isocitrate Dehydrogenase/genetics* ; NADP ; Reactive Oxygen Species ; Autolysis ; Adenosine Triphosphate

The autolysis of brewer's yeast seriously affects the quality of beer and the quality of yeast is considered as one of the key factors in beer brewing. Previous studies on brewer's yeast autolysis showed that RLM1 gene, an important transcription factor in cell integrity pathway, is closely related to the autolysis of yeast. In this study, RLM1 was knocked out and overexpressed in a haploid brewer's yeast. RLM1 disruption resulted in poor anti-autolysis performance of yeast, whereas overexpression of RLM1 contributed to the anti-autolytic ability of yeast. In addition, RLM1 gene knockout affected the osmotic stress resistance, cell wall damage resistance, nitrogen starvation resistance and temperature tolerance of yeast strain. The transcriptional level of GAS1 involved in cell wall assembly and DNA damage response was regulated along with the expression of RLM1, whereas other genes in CWI pathway did not show apparent regularity. RLM1 might mainly affect the expression of GAS1 so as to improve the stress resistance of lager yeast in harsh environment. The result from this study help further understand the mechanism of yeast autolysis and lay a foundation for breeding brewer's yeast strain with better anti-autolytic ability.
Autolysis ; Beer ; Cell Wall ; Humans ; MADS Domain Proteins ; Saccharomyces cerevisiae ; Saccharomyces cerevisiae Proteins

Yeast autolysis under solid-state fermentation can effectively promote the release of various active substances, thereby improving the quality of yeast products. The optimal process for yeast autolysis under solid-state fermentation was obtained by optimizing the autolysis temperature, autolysis time and the zinc ion concentration. We analyzed the indexes of free amino acid, soluble protein and α-amino nitrogen in the fermentation material, as well as A₂₆₀/A₂₈₀ ratio to determine yeast autolysis process conditions in the solid-state fermentation. On the basis of the obtained data, L₉ (3³) orthogonal test was designed to optimize the solid-state fermentation parameters for yeast autolysis: temperature at 40, 50 and 55 °C; time 12, 18 and 24 h; zinc ion concentration 2, 4 and 8 mg/kg. The optimum process conditions for yeast autolysis were: autolysis temperature 55 °C, time 18 h, zinc ion concentration 2 mg/kg, and soluble protein content reached 9.31 mg/g, free amino acid 14.36 mg/g, α-amino nitrogen 10.16 μg/g and A₂₆₀/A₂₈₀ 1.73. After optimization of the process, the soluble protein, free amino acid and α-amino nitrogen contents of the yeast autolysis production can be significantly increased, thereby obviously improving the quality of the composite culture.
Amino Acids ; Autolysis ; Fermentation ; Humans ; Hydrogen-Ion Concentration ; Nitrogen ; Saccharomyces cerevisiae ; Temperature

The concentration of glucose in the vitreous humor serves as an important diagnostic marker for diabetic mellitus in post-mortem examinations, as the vitreous humor can be easily collected and the glucose test using vitreous humor is not significantly affected by cell autolysis and hemolysis. For a quick and effective glucose test, we suggest a dipstick test of the vitreous humor during autopsy. The results were evaluated and compared with other methods for significance testing. In this study, vitreous humor was analyzed from 257 autopsy cases. Qualitative concordance rate of the dipstick test for glucose and the hexokinase test was 98.7%, positive prediction rate was 89.6%, and negative prediction rate was 100%. However, there was no significant correlation between the dipstick glucose test and the hexokinase test. We conclude that the dipstick glucose test is effective and useful for post-mortem glucose screening testing and for additional post-mortem diabetes testing. Recently, the importance of post-mortem glucose testing has increased with the increase in deaths from diabetes complications. The use of the dipstick glucose test in autopsy practice can improve forensic medicine in Korea.
Autolysis ; Autopsy* ; Diabetes Complications ; Forensic Medicine ; Glucose* ; Hemolysis ; Hexokinase ; Korea ; Mass Screening ; Vitreous Body

With the development of high gravity brewing, yeast cells are exposed to multiple brewing-associated stresses, such as increased osmotic pressure, enhanced alcohol concentration and nutritional imbalance. These will speed up yeast autolysis, which seriously influence beer flavor and quality. To increase yeast anti-autolytic ability, FKS1 overexpression strain was constructed by 18S rDNA. The concentration of β-1,3-glucan of overexpression strain was 62% higher than that of wild type strain. Meantime, FKS1 overexpression strain increased anti-stress ability at 8% ethanol, 0.4 mol/L NaCl and starvation stress. Under simulated autolysis, FKS1 showed good anti-autolytic ability by slower autolysis. These results confirms the potential of FKS1 overexpression to tackle yeast autolysis in high-gravity brewing.
Autolysis ; Beer ; Echinocandins ; genetics ; Glucosyltransferases ; genetics ; Hypergravity ; Membrane Proteins ; genetics ; Saccharomyces cerevisiae ; cytology ; Saccharomyces cerevisiae Proteins ; genetics

OBJECTIVE: To analyze pathological characteristics of organs recovered during forensic autopsy submitted by legal medicine experts. METHODS: From Baoji city, 358 cases of forensic autopsy specimens from a series of routine exams were collected. And histopathological diagnoses were reviewed. RESULTS: Majority of the 358 cases were young men. The major causes of death were trauma, sudden death and poisoning. The cause of death was determined with histology in 250 cases. No typical histological changes were noted in 101 cases. The tissue autolysis and decomposition were present in 7 cases. The major pathological diagnosis was cardiovascular disease, followed by diseases in respiratory, nervous, and digestive systems. CONCLUSION Forensic autopsy with its professional characteristics, is different from regular autopsy. When diagnosing cause of death by histopathological examination, pathologists should collaborate with legal medicine experts to know the details of the cases, circumstances surrounding the death, and specific forensic pathological characteristics.
Anxiety ; Autolysis ; Autopsy ; Cardiovascular Diseases ; Cause of Death ; China ; Cooperative Behavior ; Death, Sudden ; Female ; Forensic Medicine ; Forensic Pathology ; Humans ; Interprofessional Relations ; Male

The intrauterine retention time (IURT) after fetal death can be estimated from the loss of nuclear basophilia. We therefore attempted to derive an autolysis equation to estimate IURT in experimental rat fetuses and human fetal autopsy slides. The degree of loss of nuclear basophilia in various tissues was assessed by hematoxylin and eosin (H & E) staining. Fetal rat tissues showed different rates of autolysis, allowing for the construction of an experimental autolysis curve. We also reviewed the H & E stained slides obtained from 27 human fetal autopsy cases with well-documented death intervals. The degree of autolysis in various tissues was evaluated using percentile scores (PS). Using the findings from H&E staining, we derived the equation Ln (PS/[100-PS]) = 2.62716-0.02377 x IURT. However, this equation or autolysis scores showed some limitations. Owing to the inconsistency of PS, this equation is reliably applicable only within 24 hours of intrauterine fetal death. In the fetal autopsy review, fetal hydrops, local effusion, and sepsis also contributed to accelerated autolysis.
Animals ; Autolysis ; Autopsy ; Eosine Yellowish-(YS) ; Fetal Death* ; Fetus ; Hematoxylin ; Humans ; Hydrops Fetalis ; Rats ; Sepsis

Vegetative growth signaling of the opportunistic human pathogenic fungus Aspergillus fumigatus is mediated by GpaA (Galpha). FlbA is a regulator of G protein signaling, which attenuates GpaA-mediated growth signaling in this fungus. The flbA deletion (DeltaflbA) and the constitutively active GpaA (GpaA(Q204L)) mutants exhibit enhanced proliferation, precocious autolysis, and reduced asexual sporulation. In this study, we demonstrate that both mutants also show enhanced tolerance against H2O2 and their radial growth was approximately 1.6 fold higher than that of wild type (WT) in medium with 10 mM H2O2. We performed quantitative PCR (qRT-PCR) for examination of mRNA levels of three catalase encoding genes (catA, cat1, and cat2) in WT and the two mutants. According to the results, while levels of spore-specific catA mRNA were comparable among the three strains, cat1 and cat2 mRNA levels were significantly higher in the two mutants than in WT. In particular, the DeltaflbA mutant showed significantly enhanced and prolonged expression of cat1 and precocious expression of cat2. In accordance with this result, activity of the Cat1 protein in the DeltaflbA mutant was higher than that of gpaA(Q204L) and WT strains. For activity of the Cat2 protein, both mutants began to show enhanced activity at 48 and 72 hr of growth compared to WT. These results lead to the conclusion that GpaA activates expression and activity of cat1 and cat2, whereas FlbA plays an antagonistic role in control of catalases, leading to balanced responses to neutralizing the toxicity of reactive oxygen species.
Aspergillus fumigatus* ; Aspergillus* ; Autolysis ; Catalase ; Fungi ; GTP-Binding Proteins* ; Humans ; Polymerase Chain Reaction ; Reactive Oxygen Species ; RNA, Messenger

Cell autolysis plays important physiological roles in the life cycle of clostridial cells. Understanding the genetic basis of the autolysis phenomenon of pathogenic Clostridium or solvent producing Clostridium cells might provide new insights into this important species. Genes that might be involved in autolysis of Clostridium acetobutylicum, a model clostridial species, were investigated in this study. Twelve putative autolysin genes were predicted in C. acetobutylicum DSM 1731 genome through bioinformatics analysis. Of these 12 genes, gene SMB_G3117 was selected for testing the in tracellular autolysin activity, growth profile, viable cell numbers, and cellular morphology. We found that overexpression of SMB_G3117 gene led to earlier ceased growth, significantly increased number of dead cells, and clear electrolucent cavities, while disruption of SMB_G3117 gene exhibited remarkably reduced intracellular autolysin activity. These results indicate that SMB_G3117 is a novel gene involved in cellular autolysis of C. acetobutylicum.
Autolysis ; genetics ; Clostridium acetobutylicum ; genetics ; metabolism ; Computational Biology ; Genes, Bacterial ; N-Acetylmuramoyl-L-alanine Amidase ; genetics ; metabolism ; Temperature

OBJECTIVE: To compare the pathomorphologic changes between the pancreas in acute necrotizing pancreatitis (ANP) and that in acute deaths of rats (within 48 hours) so as to find the distinctions. METHODS: The animal models of ANP and other acute deaths (electroshock, mechanic asphyxia/strangle, and acute poisoning with tetramine) were established according to the criteria. Half-quantitative grading and image quantitative analysis methods were employed to observe the gross and microscopic changes of the pancreases. RESULTS: Three features including inflammation infiltrate, fat necrosis and calcium deposit in the ANP group were considerably different from that in other acutely died rat group (P<0.05). CONCLUSION Inflammation infiltrate, fat necrosis and calcium deposit are the most important pathologic features found in ANP by common light microscope, distinguishing ANP from postmortem pancreatic autolysis.
Animals ; Autolysis ; Female ; Forensic Pathology ; Male ; Pancreas/pathology* ; Pancreatitis, Acute Necrotizing/pathology* ; Poisoning/pathology* ; Postmortem Changes ; Rats ; Rats, Sprague-Dawley