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Author(s): Y. Nishihata (corresponding author) [1]; J. Mizuki [1]; T. Akao [1, 2]; H. Tanaka [3]; M. Uenishi [3]; M. Kimura [4]; T. Okamoto [2, 4]; N. Hamada [5] Catalytic [...]

Shaoyao-Gancao-Tang (SGT), a traditional Chinese herbal medicine (Kampo formulation) containing Shaoyao (Paeoniae Radix) and Gancao (Glycyrrhizae Radix), is co-administered with laxative sodium picosulfate as a premedication for relieving the pain accompanying colonoscopy. Paeoniflorin (PF), an active glycoside of SGT, is metabolized into the antispasmodic agent paeonimetabolin-I (PM-I) by intestinal bacteria after oral administration. The objective of the present study was to investigate whether the co-administered laxative (sodium picosulfate) influences the metabolism of PF to PM-I by intestinal bacteria. We found that the PF-metabolizing activity of intestinal bacteria in rat feces was significantly reduced to approximately 34% of initial levels by a single sodium picosulfate pretreatment and took approximately 6 days to recover. Repeated administration of SGT after the sodium picosulfate pretreatment significantly shortened the recovery period to around 2 days. Similar results were also observed for plasma PM-I concentration. Since PM-I has muscle relaxant activity, the present results suggest that repetitive administration of SGT after sodium picosulfate pretreatment might be useful to relieve the pain associated with colonoscopy. [ABSTRACT FROM AUTHOR]

Hineka is a type of off-flavor of sake and is attributed to the presence of several compounds, including a major one called dimethyl trisulfide (DMTS). The production of the main precursor of DMTS involves yeast methionine salvage pathway. The DMTS-producing potential (DMTS-pp) of sake brewed using the Km67 strain, a non-Kyokai sake yeast, is lower than that of sake brewed using Kyokai yeast; however, the detailed mechanism is unclear. We focused on S-adenosyl-methionine (SAM) and aimed to elucidate the mechanism that prevents DMTS production in sake brewed using the Km67 strain. We revealed that SAM is involved in DMTS production in sake, and that the conversion of SAM to the DMTS precursor occurs through an enzymatic reaction rather than a chemical reaction. Based on previous reports on ADO1 and MDE1 genes, sake brewing tests were performed using the Km67 Δmde1, Δado1, and Δmde1Δado1 strains. A comparison of the SAM content of pressed sake cakes and DMTS-pp of sake produced using the Km67 Δado1 strain showed an increase in both SAM content and DMTS-pp compared to those produced using the parent strain. However, the Km67 Δmde1Δado1 strain showed little increase in DMTS-pp compared to the Km67 Δmde1 strain, despite an increase in SAM content. These results suggest that SAM accumulation in yeast plays a role in the production of DMTS in sake through the methionine salvage pathway. Moreover, the low SAM-accumulation characteristic of the Km67 strain contributes to low DMTS production in sake., (Copyright © 2024 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

This study aimed to assess the effects of thienopyridine-class antiplatelet agents (including ticlopidine, clopidogrel, and prasugrel) on bleeding complications in patients who underwent robot-assisted radical prostatectomy. This cohort study used a database for robot-assisted radical prostatectomy at 23 tertiary centers nationwide between 2011 and 2022. Patients who received thienopyridines (thienopyridine group) were compared with those who received aspirin monotherapy (aspirin group). The primary outcome was the incidence of bleeding complications. High-grade complications were defined as Clavien-Dindo grade III or higher. The risks of these outcomes were evaluated using inverse probability of treatment weighted regression models. The study results demonstrated that thienopyridine therapy was associated with a higher risk of overall bleeding complications (OR: 3.62, 95%CI 1.54-8.49). The increased risks of the thienopyridine group were detected for low-grade bleeding complications (OR: 3.20, 95%CI 1.23-8.30) but not for high-grade bleeding complications (OR: 5.23, 95%CI 0.78-34.9). The increased risk of bleeding complications was not observed when thienopyridine was discontinued (OR: 2.52, 95%CI 0.83-7.70); however, it became apparent when it was continued perioperatively (OR: 4.35, 95%CI 1.14-16.61). In conclusion, thienopyridine increased the incidence of bleeding complications, particularly low-grade bleeding complications, following robot-assisted radical prostatectomy. These bleeding effects emerged when thienopyridine was continued perioperatively., (© 2024. The Author(s).)

The EHL1/2/3 genes were identified by whole-genome sequencing of Kyokai No. 7 (K7), which is a well-known representative Japanese sake yeast Saccharomyces cerevisiae. The genes are present in K7, but not in laboratory strain S288C. Although the genes were presumed to encode epoxide hydrolase based on homology analysis, their effect on cellular metabolism in sake yeast has not yet been clarified. We constructed ehl1/2/3 mutants harboring a stop codon in each gene using the haploid yeast strain H3 as the parental strain, which was derived from K701, and investigated the physiological role and effects of the EHL1/2/3 genes on sake quality. Metabolome analysis and vitamin requirement testing revealed that the EHL1/2/3 genes are partly responsible for the synthesis of pantothenate. For fermentation profiles, ethanol production by the ehl1/2/3 mutant was comparable with that of strain H3, but succinate production was decreased in the ehl1/2/3 mutant compared to strain H3 when cultured in yeast malt (YM) medium containing 10% glucose and during sake brewing. Ethyl hexanoate and isoamyl acetate levels in the ehl1/2/3 mutant strain were decreased compared to those of strain H3 during sake brewing. Thus, the EHL1/2/3 genes did not affect ethanol production but did affect the production of organic acids and aromatic components during sake brewing., (Copyright © 2023 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Biotin is an essential coenzyme that is bound to carboxylases and participates in fatty acid synthesis. The fact that sake yeast exhibit biotin prototrophy while almost all other Saccharomyces cerevisiae strains exhibit biotin auxotrophy, implies that biotin prototrophy is an important factor in sake brewing. In this study, we inserted a stop codon into the biotin biosynthetic BIO3 gene (cording for 7,8-diamino-pelargonic acid aminotransferase) of a haploid sake yeast strain using the marker-removable plasmid pAUR135 and investigated the fermentation profile of the resulting bio3 mutant. Ethanol production was not altered when the bio3 mutant was cultured in Yeast Malt (YM) medium containing 10% glucose at 15 °C and 30 °C. Interestingly, ethanol production was also not changed during the sake brewing process. On the other hand, the levels of organic acids in the bio3 mutant were altered after culturing in YM medium and during sake brewing. In addition, ethyl hexanoate and isoamyl acetate levels decreased in the bio3 mutant during sake brewing. Metabolome analysis revealed that the decreased levels of fatty acids in the bio3 mutant were attributed to the decreased levels of ethyl hexanoate. Further, the transcription level of genes related to the synthesis of ethyl hexanoate and isoamyl acetate were significantly reduced. The findings indicated that although the decrease in biotin biosynthesis did not affect ethanol production, it did affect the synthesis of components such as organic acids and aromatic compounds. Biotin biosynthesis ability is thus a key factor in sake brewing., (Copyright © 2023 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Modification of the genetic background and, in some cases, the introduction of targeted mutations can play a critical role in producing trait characteristics during the breeding of crops, livestock, and microorganisms. However, the question of how similar trait characteristics emerge when the same target mutation is introduced into different genetic backgrounds is unclear. In a previous study, we performed genome editing of AWA1 , CAR1 , MDE1 , and FAS2 on the standard sake yeast strain Kyokai No. 7 to breed a sake yeast with multiple excellent brewing characteristics. By introducing the same targeted mutations into other pedigreed sake yeast strains, such as Kyokai strains No. 6, No. 9, and No. 10, we were able to create sake yeasts with the same excellent brewing characteristics. However, we found that other components of sake made by the genome-edited yeast strains did not change in the exact same way. For example, amino acid and isobutanol contents differed among the strain backgrounds. We also showed that changes in yeast cell morphology induced by the targeted mutations also differed depending on the strain backgrounds. The number of commonly changed morphological parameters was limited. Thus, divergent characteristics were produced by the targeted mutations in pedigreed sake yeast strains, suggesting a breeding strategy to generate a variety of sake yeasts with excellent brewing characteristics.

The sorghum plant bug, Stenotus rubrovittatus (order Heteroptera: family Miridae), is a notorious insect pest in Japan that causes pecky rice. In the present study, we sampled this insect pest in the northern part of Honshu Island in Japan and investigated its associated microbiota. The results obtained showed that Pantoea dominated the associated microbiota and was the sole genus detected in all samples. The dominant Pantoea were phylogenetically close to rice pathogens. The present results suggest that the sorghum plant bug needs to be regarded and controlled not only as a notorious insect pest, but also as a potential vector of rice pathogenic Pantoea spp.

Introduction: Immediate appendectomy for acute appendicitis with abscess has a high frequency of ileocecal resection and postoperative complications compared with interval appendectomy after conservative treatment. The optimal approach to acute appendicitis with abscess remains controversial., Presentation of Case: A 69-year-old woman was referred to our hospital for abdominal pain. A computed tomography scan revealed an enlarged abscess around the cecum. The diagnosis was perforated appendicitis with abscess, and conservative treatment was performed. Percutaneous drainage was difficult because the abscess was near the intestinal tract. Because of the persistence of symptoms on the fourth day of hospitalization, laparotomy drainage was performed, and the patient's condition improved afterwards. Colonoscopy was performed on an outpatient follow-up to rule out malignant tumors of the colon. Interval laparoscopic appendectomy was performed 3 months after discharge to prevent appendicitis. The postoperative course was uneventful., Discussion: For this case of acute appendicitis with abscess, conservative treatment such as antibiotic therapy and laparotomy drainage was performed. Laparotomy drainage enabled us to approach the abscess directly and minimized the risk of its spread into the abdominal cavity compared to the laparoscopic approach. Interval laparoscopic appendectomy was more effective and easier for this case of appendectomy, wherein adhesions to the abdominal wall were expected compared to laparotomy., Conclusion: Conservative treatment approaches, such as drainage and antibiotic therapy, can be first-line for appendicitis with abscesses. Interval laparoscopic appendectomy can be useful to resect the appendix and observe the abdominal cavity., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Pressed sake cake, a by-product of sake brewing, is a rich dietary source of folates, which are important vitamins for humans. However, considerable losses of folates occur during storage and cooking. We have previously reported that Km67, the house sake yeast strain of Kiku-masamune sake brewery, can accumulate high folate levels. In this study, we found that the folate content of pressed sake cakes produced with Km67 remained at approximately their maximum level after the fermentation activity stopped. To elucidate the mechanisms of high folate accumulation in Km67, we analyzed the expression of 23 folate-metabolizing genes. The expression of ABZ1 and FOL3 was almost always higher in Km67 than in Kyokai no. 701 yeast (K701), which suggested that enhanced expression of the genes involved in folate biosynthesis was a mechanism of high folate accumulation in Km67. We found that the folates of Km67 pressed sake cakes were quantitatively stable at 4°C under refrigerated storage conditions. In addition, the homocysteine content of Km67 pressed sake cakes was almost always higher than that of K701 pressed sake cakes. This result suggests that a reason for high folate accumulation in Km67 yeast is the need to reduce the intracellular concentration of homocysteine. Our results provide biologically meaningful information on folate metabolism in yeast.

A 67-year-old man who had been pinned between a basket crane and a tree complained of severe pain in his lower back and a decreased appetite. Laparotomy after decompressing the gastrointestinal tract revealed incarceration of an ileal loop within a fractured third lumbar vertebra. The damaged bowel was resected, and an end-to-end anastomosis was performed. Once the patient's condition had stabilised, posterior lumbar fixation was performed. There were no abdominal complications or lower limb neurological deficits during the follow-up period. Enhanced CT and MRI had been helpful in making the diagnoses. Histopathological examination revealed the aetiology of the traumatic incarceration: the intestine had been pinched as the disc space closed, and the body attempted to return to its original state by exerting countertraction., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

We report here the draft genome sequence for Saccharomyces cerevisiae strain Awamori number 101, an industrial strain used for producing awamori, a distilled alcohol beverage. It was constructed by assembling the short reads obtained by next-generation sequencing. The 315 contigs constitute an 11.5-Mbp genome sequence encoding 6,185 predicted proteins.

Sake yeast is mostly diploid, so the introduction of recessive mutations to improve brewing characteristics requires considerable effort. To construct sake yeast with multiple excellent brewing characteristics, we used an evidence-based approach that exploits genome editing technology. Our breeding targeted the AWA1 , CAR1 , MDE1 , and FAS2 genes. We introduced eight mutations into standard sake yeast to construct a non-foam-forming strain that makes sake without producing carcinogens or an unpleasant odor, while producing a sweet ginjo aroma. Small-scale fermentation tests showed that the desired sake could be brewed with our genome-edited strains. The existence of a few unexpected genetic perturbations introduced during breeding proved that genome editing technology is extremely effective for the serial breeding of sake yeast.

Kimoto-style seed mash is a traditional preparation method for sake that takes advantage of spontaneous lactic acid fermentation before the growth of yeast. Lactic acid helps decrease the pH in seed mash and control the growth of unfavorable microorganisms. In this study, we carried out a comprehensive analysis of the change in the bacterial community and chemical composition during the lactic acid fermentation stage in kimoto-style seed mash preparation. The bacterial transitions were diverse at five sake breweries, but they exhibited three patterns. Lactobacillus sakei was the dominant species in the later stage of lactic acid fermentation in all sake breweries. This species was found to be the most important bacterium for the accumulation of lactic acid, because its average production rate of lactic acid in seed mash reached 4.44 × 10 -11  mg cell -1 h -1 , which is 10 times higher than those of other species. As a result of specific growth rate analysis, it was revealed that the growth rate of L. sakei was influenced by the strain, pH, and temperature. The effects of pH and temperature were explained by the square root model, and the result indicates that the strains isolated in this study were incapable of growth below pH 3.9. The growth curve predicted using the growth model fit the actual cell density in two out of five sake breweries; however, our model did not work well for the remaining three sake breweries, and we presume that the error was caused by the strain or an unknown factor. IMPORTANCE It is important to produce lactic acid in kimoto-style seed mash; however, the bacterial transition is different depending on the sake brewery. The reason why there are diverse bacterial transitions during kimoto-style seed mash preparation for each sake brewery is unclear so far, and it causes difficulty in starting kimoto-style seed mash. Our findings indicate that the changes in pH caused by lactic acid bacteria grown prior to L. sakei in seed mash influence the growth of L. sakei and are related to the diversity of the bacterial transition. This study uses comprehensive analytical methods to reveal that there is a diversity of bacterial transition and chemical compositions in kimoto-style seed mash depending on the sake brewery and to explain the differences in bacterial transition depending on the characteristics of L. sakei ., (Copyright © 2021 American Society for Microbiology.)

Among sake yeast strains, Kyokai no. 7 (K7) and its closely related strains (K7 group) are predominantly used because of their excellent brewing properties. In the sake industrial sector, the need for various types of yeast strains is high. Although crossbreeding is an effective method for generating genetic diversity that should result in diverse characteristics, most K7 group strains lack normal sporulation ability, including the ability to undergo meiotic chromosomal recombination, which leads to difficulties in crossbreeding. Accordingly, the improvement of sake yeast strains primarily depends on mutagenesis and suitable selection in a stepwise manner. Our recent study revealed that the long-preserved sake yeast strain Hiroshima no. 6 (H6) does not belong to the K7 group despite genetically being extremely similar. In addition, H6 exhibited normal sporulation. Thus, we isolated haploid cells from H6 and mated them with previously isolated haploid cells of K7 group strains. The crossbred diploid strains had normal sporulation ability; hence, we performed tetrad analysis. The brewing characteristics of the obtained haploid set were extremely diverse. Principal component analysis based on the volatile and organic acid components measured using small-scale sake brewing tests revealed that the haploid strains derived from each diploid strain displayed a characteristic distribution. Thus, we demonstrated the availability of genetic crossbreeding using H6 with sporulation ability to facilitate both the development of novel sake yeast strains with many desirable characteristics and analyses of the function of sake yeast., (Copyright © 2020 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

The small molecule IACS-010759 has been reported to potently inhibit the proliferation of glycolysis-deficient hypoxic tumor cells by interfering with the functions of mitochondrial NADH-ubiquinone oxidoreductase (complex I) without exhibiting cytotoxicity at tolerated doses in normal cells. Considering the significant cytotoxicity of conventional quinone-site inhibitors of complex I, such as piericidin and acetogenin families, we hypothesized that the mechanism of action of IACS-010759 on complex I differs from that of other known quinone-site inhibitors. To test this possibility, here we investigated IACS-010759's mechanism in bovine heart submitochondrial particles. We found that IACS-010759, like known quinone-site inhibitors, suppresses chemical modification by the tosyl reagent AL1 of Asp 160 in the 49-kDa subunit, located deep in the interior of a previously proposed quinone-access channel. However, contrary to the other inhibitors, IACS-010759 direction-dependently inhibited forward and reverse electron transfer and did not suppress binding of the quinazoline-type inhibitor [ 125 I]AzQ to the N terminus of the 49-kDa subunit. Photoaffinity labeling experiments revealed that the photoreactive derivative [ 125 I]IACS-010759-PD1 binds to the middle of the membrane subunit ND1 and that inhibitors that bind to the 49-kDa or PSST subunit cannot suppress the binding. We conclude that IACS-010759's binding location in complex I differs from that of any other known inhibitor of the enzyme. Our findings, along with those from previous study, reveal that the mechanisms of action of complex I inhibitors with widely different chemical properties are more diverse than can be accounted for by the quinone-access channel model proposed by structural biology studies., (© 2020 Tsuji et al.)

Folates are important vitamins in human nutrition. Pressed sake cake, a brewing by-product of sake, is a rich dietary source of folates derived from sake yeast (Saccharomyces cerevisiae). The National Research Institute of Brewing investigated 106 samples of pressed sake cake and revealed that three samples containing large amounts of folates were produced by Km67 yeast derived from the house sake yeast strain of Kiku-Masamune sake brewery. In this study, we performed sake brewing tests using Km67 and Kyokai no. 7 group strains and confirmed that Km67 yeast contributed to the production of pressed sake cake containing large amounts of folates. To elucidate the mechanisms of high folate accumulation in Km67, we performed whole-genome sequence analysis in Km67 and then screened 10 folate-metabolizing genes showing different sequences in Km67 and K7 strains. By folate analysis of each gene-disrupted strain derived from strain BY4743, we also selected four genes having significant effects on folate content in yeast from 10 candidate genes. Folate analysis of gene-disrupted yeast strains complemented with either Km67-type genes or K7-type genes revealed that the Km67-type HMT1 gene was related to high folate accumulation not only in laboratory yeast but also in sake yeast. In this gene, Leu63Phe was present in the methyltransferase motif I of Hmt1p, which was essential for the methyltransferase activity of Hmt1p. Our results and previous reports suggested that the methyltransferase activity of Km67-Hmt1p was higher than that of K7-Hmt1p, leading to enhanced production and high accumulation of folates in Km67 yeast., (Copyright © 2019 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Aim: In 1990, an epidemiological survey by ship in some Japanese islands revealed high prevalence of hepatitis viruses and human T cell leukemia virus (HTLV). A second prevalence study of these viruses were accomplished in 2018, 28 years after initial survey. Analysis of these studies provide insights about strategies of elimination of hepatitis viruses at remote areas., Materials and Methods: In 2018, prevalence of hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), and HTLV was checked in 305 subjects in the islands those covered in 1990's survey. Hepatitis A virus was checked by the presence of anti-HAV IgG in sera; HBV was affirmed when hepatitis B surface antigen (HBsAg) in sera. Hepatitis C virus infection was evaluated by the presence of antibody to HCV (anti-HCV) and infection with HTLV was estimated by immunoassay. The methodology of assessment of different hepatitis viruses were optimized on the basis of present scientific knowhow., Results: In 1990, the prevalence of HAV (presence of anti-HAV), HBV (presence of HBsAg), HCV (positivity for anti-HCV), and HTLV was found in 79.3%, 11.1%, 2.2%, and 3.3% of apparently health subjects of the islands, respectively. The prevalence of HAV, HBV, HCV, and HTLV was 47.9%, 4.6%, 1.0%, and 3.0%, respectively, in 2018. A shift of age of infected persons tilted towards right as the days progressed., Conclusion: The study indicates a scenario of elimination of hepatitis viruses in Japan as lower trends of prevalence of HAV, HBV, and HCV have been recorded in 2018 compared with 1990, mainly by preventive measures. The most notable finding is that there are almost no new case below the age of 40 years, indicating an effective containment measure against these viruses., How to Cite This Article: Akao T, Onji M, Kawasaki K, et al . Surveillance of Hepatitis Viruses in Several Small Islands of Japan by Ship: A Public Health Approach for Elimination of Hepatitis Viruses by 2030. Euroasian J Hepato-Gastroenterol 2019;9(2):57-62., Competing Interests: Source of support: Nil Conflict of interest: None, (Copyright © 2019; Jaypee Brothers Medical Publishers (P) Ltd.)

Sake yeast strains are classified into Saccharomyces cerevisiae and have a heterothallic life cycle. This feature allows cross hybridization between two haploids to breed new strains with superior characteristics. However, cross hybridization of sake yeast is very difficult because only a few spores develop in a sporulation medium, and most of these spores do not germinate. We hypothesized that these features are attributable to chromosome recombination defect in meiosis, which leads to chromosome loss. To test this hypothesis, we examined meiotic recombination of sake yeast Kyokai no. 7 (K7) using the following three methods: (i) analysis of the segregation patterns of two heterozygous sites in the same chromosome in 100 haploid K7 strains; (ii) sequencing of the whole genomes of four haploid K7 strains and comparison of the bases derived from the heterozygosities; and (iii) construction of double heterozygous disruptants of CAN1 and URA3 on the chromosome V of K7 and the examination of the genotypes of haploids after sporulation. We could not detect any recombinant segregants in any of the experiments, which indicated defect in meiotic recombination in K7. Analyses after sporulation of the same double heterozygous disruptants of K6, K9, and K10 also indicated meiotic recombination defect in these strains. Although rapamycin treatment increased the sporulation efficiency of K7, it did not increase the meiotic recombination of the double heterozygous K7. Moreover, the spo13 disruptant of the K7 derivative produced two spore asci without meiotic recombination. These results suggest that sake yeasts have defects in meiotic recombination machinery., (Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Saccharomyces cerevisiae sake yeast strain Kyokai no. 7 (K7) and its relatives carry a homozygous loss-of-function mutation in the RIM15 gene, which encodes a Greatwall family protein kinase. Disruption of RIM15 in nonsake yeast strains leads to improved alcoholic fermentation, indicating that the defect in Rim15p is associated with the enhanced fermentation performance of sake yeast cells. In order to understand how Rim15p mediates fermentation control, we here focused on target-of-rapamycin protein kinase complex 1 (TORC1) and protein phosphatase 2A with the B55δ regulatory subunit (PP2A B55δ ), complexes that are known to act upstream and downstream of Rim15p, respectively. Several lines of evidence, including our previous transcriptomic analysis data, suggested enhanced TORC1 signaling in sake yeast cells during sake fermentation. Fermentation tests of the TORC1-related mutants using a laboratory strain revealed that TORC1 signaling positively regulates the initial fermentation rate in a Rim15p-dependent manner. Deletion of the CDC55 gene, encoding B55δ, abolished the high fermentation performance of Rim15p-deficient laboratory yeast and sake yeast cells, indicating that PP2A B55δ mediates the fermentation control by TORC1 and Rim15p. The TORC1-Greatwall-PP2A B55δ pathway similarly affected the fermentation rate in the fission yeast Schizosaccharomyces pombe , strongly suggesting that the evolutionarily conserved pathway governs alcoholic fermentation in yeasts. It is likely that elevated PP2A B55δ activity accounts for the high fermentation performance of sake yeast cells. Heterozygous loss-of-function mutations in CDC55 found in K7-related sake strains may indicate that the Rim15p-deficient phenotypes are disadvantageous to cell survival. IMPORTANCE The biochemical processes and enzymes responsible for glycolysis and alcoholic fermentation by the yeast S. cerevisiae have long been the subject of scientific research. Nevertheless, the factors determining fermentation performance in vivo are not fully understood. As a result, the industrial breeding of yeast strains has required empirical characterization of fermentation by screening numerous mutants through laborious fermentation tests. To establish a rational and efficient breeding strategy, key regulators of alcoholic fermentation need to be identified. In the present study, we focused on how sake yeast strains of S. cerevisiae have acquired high alcoholic fermentation performance. Our findings provide a rational molecular basis to design yeast strains with optimal fermentation performance for production of alcoholic beverages and bioethanol. In addition, as the evolutionarily conserved TORC1-Greatwall-PP2A B55δ pathway plays a major role in the glycolytic control, our work may contribute to research on carbohydrate metabolism in higher eukaryotes., (Copyright © 2018 American Society for Microbiology.)

For several decades, almost all sake has been brewed with sake yeast Saccharomyces cerevisiae Kyokai no. 7 (K7) group strains. Although the widespread use of these strains has contributed to sake quality improvement, it may have lessened the diversity of sake gustatory properties brought about by house sake yeast (indigenous yeast of sake brewery). Sake yeast S. cerevisiae strain Km67 derives from the house yeast strain of Kiku-masamune Sake Brewing Co., Ltd., and it has been playing a central role in industrial sake brewing for decades. By using DNA sequencing, we revealed that strain Km67 does not possess specific loss-of-function mutations of stress response-related genes, which are characteristic of K7 group strains. Km67 had higher stress tolerance than K7 group strains likely because of the more efficient function of the stress response and heat shock elements in this strain. Sensory evaluation and taste sensor analysis demonstrated that sake brewed with Km67 had characteristically thicker body than sake brewed with K7 group strains. Chemical analysis suggested that unique sensory properties of the sake brewed with Km67 were due to high citramalic acid concentration. Taken together, these results revealed that strain Km67 differs from K7 group strains by genetic background and confers unique chemical composition and taste qualities upon sake it generates. It is expected that sake quality and gustatory properties will be diversified by utilizing house yeast such as strain Km67., (Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Aim: The aim of the study was to assess the implication of Zonulin, a mediator protein synthesized by intestine and the liver,in patients with chronic liver diseases., Materials and Methods: Twenty-six patients with chronic liver diseases due to hepatitis C virus (HCV) and hepatitis B virus (HBV) were enrolled in this study. Out of total 26 patients, 17 were diagnosed as chronic hepatitis (CH) and 9 were patients with liver cirrhosis (LC). Twenty-four of these patients were infected with hepatitis C virus (HCV) and the rest two by hepatitis B virus (HBV). The study was conducted at Saiseikai-Imabari Hospital, Imabari, Ehime, Japan. Serum levels of Zonulin along with different parameters of liver function test were measured in all patients and comparative analyses were accomplished., Results: The serum levels of Zonulin were significantly lower in CH patients compared to controls (p<0.001). Also, the levels of Zonulin were significantly lower in patients with LC compared to CH and normal controls (p<0.001). Further analysis revealed that serum Zonulin was significantly lower in patients with LC having ascites than those without ascites (p <0.05). There was a significant correlation of serum levels of Zonulin with platelet count, cholinesterase, and albumin in patients with chronic liver diseases., Discussion: Decreased levels of Zonulin may be related to impaired production of this mediator in the diseased liver. It will be tempting to assess the regulation of Zonulin in the liver, a production site of the mediator., Abbreviations: LC: Liver cirrhosis, CH: Chronic hepatitis, HCV: Hepatitis C virus, HBV: Hepatitis B virus, LGS: Leaky gut syndrome How to cite this article: Akao T, Morita A, Onji M, Miyake T, Watanabe R, Uehara T, Kawasaki K, Miyaike J, Oomoto M. Low Serum Levels of Zonulin in Patients with HCV-Infected Chronic Liver Diseases. Euroasian J Hepatogastroenterol, 2018;8(2):112-115., Competing Interests: Source of support: Nil Conflict of interest: None

For maltose fermentation, budding yeast Saccharomyces cerevisiae operates a mechanism that involves transporters (MALT), maltases (MALS) and regulators (MALR) collectively known as MAL genes. However, functional relevance of MAL genes during sake brewing process remains largely elusive, since sake yeast is cultured under glucose-rich condition achieved by the co-culture partner Aspergillus spp.. Here we isolated an ethyl methane sulfonate (EMS)-mutagenized sake yeast strain exhibiting enhanced maltose fermentation compared to the parental strain. The mutant carried a single nucleotide insertion that leads to the extension of the C-terminal region of a previously uncharacterized MALR gene YPR196W-2, which was renamed as MAL73. Introduction of the mutant allele MAL73L with extended C-terminal region into the parental or other sake yeast strains enhanced the growth rate when fed with maltose as the sole carbon source. In contrast, disruption of endogenous MAL73 in the sake yeasts decreased the maltose fermentation ability of sake yeast, confirming that the original MAL73 functions as a MALR. Importantly, the MAL73L-expressing strain fermented more maltose in practical condition compared to the parental strain during sake brewing process. Our data show that MAL73(L) is a novel MALR gene that regulates maltose fermentation, and has been functionally attenuated in sake yeast by single nucleotide deletion during breeding history. Since the MAL73L-expressing strain showed enhanced ability of maltose fermentation, MAL73L might also be a valuable tool for enhancing maltose fermentation in yeast in general., Competing Interests: TO, FO, HH and EO are employees of Suntory Global Innovation Center Ltd (SIC), a company affiliated to Suntory Holdings Ltd. SIC financially provides salaries of TO, FO, HH and EO and research materials of this study. There are no patents, products in development or marketed products to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

The effect of chromosomal aneuploidy on the brewing characteristics of brewery yeasts has not been studied. Here we report that chromosomal aneuploidy in sake brewery yeast ( Saccharomyces cerevisiae ) leads to the development of favorable brewing characteristics. We found that pyruvate-underproducing sake yeast, which produces less off-flavor diacetyl, is aneuploid and trisomic for chromosomes XI and XIV. To confirm that this phenotype is due to aneuploidy, we obtained 45 haploids with various chromosomal additions and investigated their brewing profiles. A greater number of chromosomes correlated with a decrease in pyruvate production. Especially, sake yeast haploids with extra chromosomes in addition to chromosome XI produced less pyruvate than euploids. Mitochondrion-related metabolites and intracellular oxygen species in chromosome XI aneuploids were higher than those in euploids, and this effect was canceled in their "petite" strains, suggesting that an increase in chromosomes upregulated mitochondrial activity and decreased pyruvate levels. These findings suggested that an increase in chromosome number, including chromosome XI, in sake yeast haploids leads to pyruvate underproduction through the augmentation of mitochondrial activity. This is the first report proposing that aneuploidy in brewery yeasts improves their brewing profile. IMPORTANCE Chromosomal aneuploidy has not been evaluated in development of sake brewing yeast strains. This study shows the relationship between chromosomal aneuploidy and brewing characteristics of brewery yeast strains. High concentrations of pyruvate during sake storage give rise to α-acetolactate and, in turn, to high concentrations of diacetyl, which is considered an off-flavor. It was demonstrated that pyruvate-underproducing sake yeast is trisomic for chromosome XI and XIV. Furthermore, sake yeast haploids with extra chromosomes produced reduced levels of pyruvate and showed metabolic processes characteristic of increased mitochondrial activity. This novel discovery will enable the selection of favorable brewery yeasts by monitoring the copy numbers of specific chromosomes through a process that does not involve generation/use of genetically modified organisms., (Copyright © 2017 American Society for Microbiology.)