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1.
J Biochem Mol Toxicol ; 38(4): e23676, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38561971

ABSTRACT

Although the treatment of ovarian cancer has made great progress, there are still many patients who are not timely detected and given targeted therapy due to unknown pathogenesis. Recent studies have found that hsa_circ_0015326 is upregulated in ovarian cancer and is involved in the proliferation, invasion, and migration of ovarian cancer cells. However, whether hsa_circ_0015326 can be used as a new target of ovarian cancer needs further investigation. Therefore, the effect of hsa_circ_0015326 on epithelial ovarian cancer was investigated in this study. At first, si-hsa_circ_0015326 lentivirus was transfected into epithelial ovarian cancer cells. Then real-time fluorescence quantitative PCR (qRT-PCR) was used to detect hsa_circ_0015326 level. The proliferation of ovarian cancer cells was detected by CCK-8 assay. The horizontal and vertical migration abilities of the cells were detected by wound-healing assay and Transwell assay, respectively. Transwell assay was also used to determine the invasion rate. As for the apoptosis rate, it was assessed by flow cytometry. As a result, the expression level of hsa_circ_0015326 in A2780 and SKOV3 was found to be higher than that in IOSE-80. However, after transfecting si-hsa_circ_0015326 and si-NC into the cells, the proliferation, migration, and invasion abilities of A2780 and SKOV3 cells in the si-hsa_circ_0015326 group were significantly reduced in comparison to those in the si-NC and mock groups, while their apoptosis rates were elevated. Collectively, silencing hsa_circ_0015326 bears the capability of inhibiting the proliferation, migration, and invasion of ovarian cancer cells while increasing apoptosis rate. It can be concluded that hsa_circ_0015326 promotes the malignant biological activities of epithelial ovarian cancer cells.


Subject(s)
MicroRNAs , Ovarian Neoplasms , Humans , Female , RNA/metabolism , Carcinoma, Ovarian Epithelial/genetics , RNA, Circular/genetics , RNA, Circular/metabolism , Cell Line, Tumor , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Cell Proliferation , Apoptosis , MicroRNAs/metabolism , Cell Movement
2.
Food Microbiol ; 110: 104157, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36462813

ABSTRACT

Microbes have evolved multiple mechanisms to resist environmental stresses, which are regulated in complex and delicate ways. Though the role of cell membranes in acid resistance from the perspective of physicochemical properties and membrane proteins has been deeply studied, the function of eisosomes is still in its infancy. In this study, we firstly reported the dynamic changes of eisosomes under acid stress and the decreased acid tolerance of yeasts caused by eisosome disruption. Physiological indicators and non-targeted lipid profiling revealed that eisosome disruption caused changes in multiple lipids and imbalances in lipid homeostasis, which are responsible for membrane integrity damage. Thus the increased infiltration of carboxylic acids and the raised ROS levels were detected in strains with disrupted eisosome assembly, resulting in decreased cellular tolerance. The results here provide novel insights into the acid-resistant mechanism of yeasts from the perspective of the cell membrane subdomain, which has practical impacts on green biological manufacturing and food preservation.


Subject(s)
Membrane Proteins , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genetics , Cell Membrane , Carboxylic Acids , Lipids
3.
Food Microbiol ; 95: 103713, 2021 May.
Article in English | MEDLINE | ID: mdl-33397627

ABSTRACT

Higher alcohols are important flavor substance in alcoholic beverages. The content of α-amino nitrogen (α-AN) in the fermentation system affects the formation of higher alcohols by Saccharomyces cerevisiae. In this study, the effect of α-AN concentration on the higher alcohol productivity of yeast was explored, and the mechanism of this effect was investigated through metabolite and transcription sequence analyses. We screened 12 most likely genes and constructed the recombinant strain to evaluate the effect of each gene on high alcohol formation. Results showed that the AGP1, GDH1, and THR6 genes were important regulators of higher alcohol metabolism in S. cerevisiae. This study provided knowledge about the metabolic pathways of higher alcohols and gave an important reference for the breeding of S. cerevisiae with low-yield higher alcohols to deal with the fermentation system with different α-AN concentrations in the brewing industry.


Subject(s)
Alcohols/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Fermentation , Flavoring Agents , Gene Expression Profiling , Genes, Regulator , Metabolic Networks and Pathways , Nitrogen/metabolism , Saccharomyces cerevisiae Proteins/metabolism
4.
Zhongguo Zhong Yao Za Zhi ; 44(19): 4257-4262, 2019 Oct.
Article in Zh | MEDLINE | ID: mdl-31872707

ABSTRACT

This study is to investigate the compatibility mechanism of Danshen-Chuanxiong drug pair on the pharmacokinetics of four phenolic acids. A UPLC-MS/MS method for quantitative determination of salvianolic acid B( Sal B),rosmarinic acid( RA),lithospermic acid( LA) and ferulic acid( FA) in plasma and heart tissue of rats was established. After single salvianolic acids and Chuanxiong-extract or combined intravenous infusion was given to rats,plasma samples and heart tissues in different time were collected. The chromatographic separation was performed on a BEH C18 column using 0. 15% formic acid-acetonitrile as mobile phase for gradient elution. A triple-quadrupole tandem mass spectrometry equipped with an electrospray ionization source was used as detector operating on multiple-reaction monitoring( MRM) scanning in negative ionization mode. Full validation of UPLC method including calibration curves,accuracy,precision,repeatability and matrix effect was investigated to comply with quantitative analysis requirements for biological samples. There were significant differences in the major pharmacokinetic parameters of Sal B,FA and RA for intravenous infusion of salvianolic acids and Chuanxiong-extract or combined in rat plasma. The AUC of Sal B and FA were increased above 40% and100%,respectively. Their Vd and CL were dropped evidently. t1/2 and Vd of RA increased above 130%. The concentration of four phenolic acids were all increased obviously in heart tissue comparing with single infusion. These results demonstrated that the compatibility mechanism of Danshen-Chuanxiong drug pair showed synergistic effect.


Subject(s)
Drugs, Chinese Herbal/metabolism , Heart/physiology , Salvia miltiorrhiza , Tandem Mass Spectrometry , Animals , Chromatography, High Pressure Liquid , Chromatography, Liquid , Hydroxybenzoates , Rats , Rats, Sprague-Dawley , Reproducibility of Results
5.
Appl Microbiol Biotechnol ; 102(4): 1783-1795, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29305698

ABSTRACT

Higher alcohols significantly influence the quality and flavor profiles of Chinese Baijiu. ILV1-encoded threonine deaminase, LEU1-encoded α-isopropylmalate dehydrogenase, and LEU2-encoded ß-isopropylmalate dehydrogenase are involved in the production of higher alcohols. In this work, ILV1, LEU1, and LEU2 deletions in α-type haploid, a-type haploid, and diploid Saccharomyces cerevisiae strains and ILV1, LEU1, and LEU2 single-allele deletions in diploid strains were constructed to examine the effects of these alterations on the metabolism of higher alcohols. Results showed that different genetic engineering strategies influence carbon flux and higher alcohol metabolism in different manners. Compared with the parental diploid strain, the ILV1 double-allele-deletion diploid mutant produced lower concentrations of n-propanol, active amyl alcohol, and 2-phenylethanol by 30.33, 35.58, and 11.71%, respectively. Moreover, the production of isobutanol and isoamyl alcohol increased by 326.39 and 57.6%, respectively. The LEU1 double-allele-deletion diploid mutant exhibited 14.09% increased n-propanol, 33.74% decreased isoamyl alcohol, and 13.21% decreased 2-phenylethanol production, which were similar to those of the LEU2 mutant. Furthermore, the LEU1 and LEU2 double-allele-deletion diploid mutants exhibited 41.72 and 52.18% increased isobutanol production, respectively. The effects of ILV1, LEU1, and LEU2 deletions on the production of higher alcohols by α-type and a-type haploid strains were similar to those of double-allele deletion in diploid strains. Moreover, the isobutanol production of the ILV1 single-allele-deletion diploid strain increased by 27.76%. Variations in higher alcohol production by the mutants are due to the carbon flux changes in yeast metabolism. This study could provide a valuable reference for further research on higher alcohol metabolism and future optimization of yeast strains for alcoholic beverages.


Subject(s)
Alcoholic Beverages/microbiology , Carbon Cycle/genetics , Ethanol/metabolism , Food Microbiology/methods , Hydro-Lyases/genetics , Metabolic Engineering/methods , Metabolic Networks and Pathways/genetics , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Threonine Dehydratase/genetics , 3-Isopropylmalate Dehydrogenase/genetics , 3-Isopropylmalate Dehydrogenase/metabolism , China , Fermentation , Gene Deletion , Humans , Hydro-Lyases/metabolism , Saccharomyces cerevisiae/enzymology , Saccharomyces cerevisiae Proteins/metabolism , Threonine Dehydratase/metabolism
6.
J Ind Microbiol Biotechnol ; 45(9): 827-838, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29936578

ABSTRACT

Maltose metabolism of baker's yeast (Saccharomyces cerevisiae) in lean dough is suppressed by the glucose effect, which negatively affects dough fermentation. In this study, differences and interactions among SNF4 (encoding for the regulatory subunit of Snf1 kinase) overexpression and REG1 and REG2 (which encodes for the regulatory subunits of the type I protein phosphatase) deletions in maltose metabolism of baker's yeast were investigated using various mutants. Results revealed that SNF4 overexpression and REG1 and REG2 deletions effectively alleviated glucose repression at different levels, thereby enhancing maltose metabolism and leavening ability to varying degrees. SNF4 overexpression combined with REG1/REG2 deletions further enhanced the increases in glucose derepression and maltose metabolism. The overexpressed SNF4 with deleted REG1 and REG2 mutant ΔREG1ΔREG2 + SNF4 displayed the highest maltose metabolism and strongest leavening ability under the test conditions. Such baker's yeast strains had excellent potential applications.


Subject(s)
AMP-Activated Protein Kinases/genetics , Carrier Proteins/genetics , Gene Deletion , Maltose/metabolism , Protein Phosphatase 1/genetics , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Transcription Factors/genetics , AMP-Activated Protein Kinases/metabolism , Fermentation , Gene Expression Regulation, Fungal , Glucose/metabolism , Monosaccharide Transport Proteins/genetics , Monosaccharide Transport Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Symporters/genetics , Symporters/metabolism , Transcription Factors/metabolism , alpha-Glucosidases/genetics , alpha-Glucosidases/metabolism
7.
Microb Cell Fact ; 16(1): 194, 2017 Nov 09.
Article in English | MEDLINE | ID: mdl-29121937

ABSTRACT

BACKGROUND: Tup1 is a general transcriptional repressor of diverse gene families coordinately controlled by glucose repression, mating type, and other mechanisms in Saccharomyces cerevisiae. Several functional domains of Tup1 have been identified, each of which has differing effects on transcriptional repression. In this study, we aim to investigate the role of Tup1 and its domains in maltose metabolism of industrial baker's yeast. To this end, a battery of in-frame truncations in the TUP1 gene coding region were performed in the industrial baker's yeasts with different genetic background, and the maltose metabolism, leavening ability, MAL gene expression levels, and growth characteristics were investigated. RESULTS: The results suggest that the TUP1 gene is essential to maltose metabolism in industrial baker's yeast. Importantly, different domains of Tup1 play different roles in glucose repression and maltose metabolism of industrial baker's yeast cells. The Ssn6 interaction, N-terminal repression and C-terminal repression domains might play roles in the regulation of MAL transcription by Tup1 for maltose metabolism of baker's yeast. The WD region lacking the first repeat could influence the regulation of maltose metabolism directly, rather than indirectly through glucose repression. CONCLUSIONS: These findings lay a foundation for the optimization of industrial baker's yeast strains for accelerated maltose metabolism and facilitate future research on glucose repression in other sugar metabolism.


Subject(s)
Maltose/metabolism , Nuclear Proteins/genetics , Repressor Proteins/genetics , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Carbohydrate Metabolism , Fermentation , Gene Deletion , Gene Expression Regulation, Fungal , Nuclear Proteins/metabolism , Protein Interaction Domains and Motifs/genetics , Repressor Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/metabolism
8.
J Ind Microbiol Biotechnol ; 44(6): 949-960, 2017 06.
Article in English | MEDLINE | ID: mdl-28176138

ABSTRACT

Acetate esters and higher alcohols greatly influence the quality and flavor profiles of Chinese Baijiu (Chinese liquor). Various mutants have been constructed to investigate the interactions of ATF1 overexpression, IAH1 deletion, and BAT2 deletion on the production of acetate esters and higher alcohols. The results showed that the overexpression of ATF1 under the control of the PGK1 promoter with BAT2 and IAH1 double-gene deletion led to a higher production of acetate esters and a lower production of higher alcohols than the overexpression of ATF1 with IAH1 deletion or overexpression of ATF1 with BAT2 deletion. Moreover, deletion of IAH1 in ATF1 overexpression strains effectively increased the production of isobutyl acetate and isoamyl acetate by reducing the hydrolysis of acetate esters. The decline in the production of higher alcohol by the ATF1 overexpression strains with BAT2 deletion is due to the interaction of ATF1 overexpression and BAT2 deletion. Mutants with varying abilities of producing acetate esters and higher alcohols were developed by genetic engineering. These strains have great potential for industrial application.


Subject(s)
Alcoholic Beverages , Fermentation , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/metabolism , Acetates/metabolism , Alcohols/metabolism , Carboxylic Ester Hydrolases/genetics , Esters/metabolism , Gene Deletion , Genetic Engineering , Pentanols/metabolism , Proteins/genetics , Proteins/metabolism , Saccharomyces cerevisiae/genetics , Transaminases/genetics
9.
Zhongguo Zhong Yao Za Zhi ; 42(12): 2413-2419, 2017 Jun.
Article in Zh | MEDLINE | ID: mdl-28822201

ABSTRACT

Herb pairs are usual clinical compatibility forms and one of compound prescription sources in Chinese medicine. Pharmacokinetic research in vivo is one of the important items in elucidating the mechanism for synergistic and attenuated mechanisms of herb pairs. The paper comprehensively summarized and systemized the pharmacokinetic researches of marker-ingredients about Danshen-Honghua and Danshen-Bingpian in order to elucidate the rationality and scientificity of herb pairs and provide some feasible suggestions on the pharmacokinetics of drugs in the future. In view of complicated system of Traditional Chinese medicines and a chemical system that is not separated from its natural state, comparative pharmacokinetic researches on marker-ingredients from the herb pairs are reasonable to elucidate the synergistic and attenuated mechanisms of monarch-subjects compatible herbs and monarch-guide compatible herbs. Such pharmacokinetic research can better explain the mechanism of drug compatibility, while the pharmacokinetic researches based on the monomer chemical compositions and marker-ingredients that have been separated from complex chemical environment of traditional Chinese Medicine are still unreasonable and should be discussed deeply.


Subject(s)
Drugs, Chinese Herbal/pharmacokinetics , Salvia miltiorrhiza/chemistry , Carthamus tinctorius , Drug Synergism , Humans , Medicine, Chinese Traditional , Research Design
10.
BMC Cancer ; 16: 491, 2016 07 18.
Article in English | MEDLINE | ID: mdl-27431492

ABSTRACT

BACKGROUND: Although epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) have become the standard care of patients with advanced EGFR-mutant non-small cell lung cancer (NSCLC), development of acquired resistance is inevitable. A secondary mutation of threonine 790 (T790M) is associated with approximately half of the cases of acquired resistance. Strategies or agents to overcome this type of resistance are still limited. In this study, enhanced antitumor effect of AT-101, a-pan-Bcl-2 inhibitor, on gefitinib was explored in NSCLC with T790M mutation. METHODS: The effect of cotreatment with AT-101 and gefitinib on the viability of NSCLC cell lines harboring acquired T790M mutation was investigated using the MTT assay. The cellular apoptosis of NSCLC cells after cotreatment with AT-101 and gefitinib was assessed by FITC-annexin V/PI assay and Western blots analysis. The potential underlying mechanisms of the enhanced therapeutic effect for AT-101 was also studied using Western blots analysis. The in vivo anti-cancer efficacy of the combination with AT-101 and gefitinib was examined in a mouse xenograft model. RESULTS: In this study, we found that treatment with AT-101 in combination with gefitinib significantly inhibited cell proliferation, as well as promoted apoptosis of EGFR TKIs resistant lung cancer cells. The apoptotic effects of the use of AT-101 was related to the blocking of antiapoptotic protein: Bcl-2, Bcl-xl, and Mcl-1 and downregrulation of the molecules in EGFR pathway. The observed enhancements of tumor growth suppression in xenografts supported the reverse effect of AT-101 in NSCLC with T790M mutation, which has been found in in vitro studies before. CONCLUSIONS: AT-101 enhances gefitinib sensitivity in NSCLC with EGFR T790M mutations. The addition of AT-101 to gefitinib is a promising strategy to overcome EGFR TKIs resistance in NSCLC with EGFR T790M mutations.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , ErbB Receptors/antagonists & inhibitors , Gossypol/analogs & derivatives , Lung Neoplasms/drug therapy , Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors , Quinazolines/therapeutic use , Animals , Apoptosis/drug effects , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Drug Synergism , ErbB Receptors/biosynthesis , ErbB Receptors/genetics , Female , Gefitinib , Gossypol/therapeutic use , Humans , Lung Neoplasms/pathology , Mice , Mice, Inbred BALB C , Mice, Nude , Myeloid Cell Leukemia Sequence 1 Protein/antagonists & inhibitors , Protein Kinase Inhibitors/therapeutic use , bcl-X Protein/antagonists & inhibitors
11.
Microb Cell Fact ; 15: 54, 2016 Apr 04.
Article in English | MEDLINE | ID: mdl-27039899

ABSTRACT

BACKGROUND: Trehalose is related to several types of stress responses, especially freezing response in baker's yeast (Saccharomyces cerevisiae). It is desirable to manipulate trehalose-related genes to create yeast strains that better tolerate freezing-thaw stress with improved fermentation capacity, which are in high demand in the baking industry. RESULTS: The strain overexpressing MAL62 gene showed increased trehalose content and cell viability after prefermention-freezing and long-term frozen. Deletion of NTH1 in combination of MAL62 overexpression further strengthens freezing tolerance and improves the leavening ability after freezing-thaw stress. CONCLUSIONS: The mutants of the industrial baker's yeast with enhanced freezing tolerance and leavening ability in lean dough were developed by genetic engineering. These strains had excellent potential industrial applications.


Subject(s)
Acclimatization/genetics , Fermentation/genetics , Freezing , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Trehalase/genetics , alpha-Glucosidases/genetics , Cold Temperature , Flour/microbiology , Gene Deletion , Gene Expression Regulation, Fungal , Organisms, Genetically Modified , Up-Regulation/genetics
12.
Appl Microbiol Biotechnol ; 100(14): 6375-6383, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27041690

ABSTRACT

Leavening ability in sweet dough is required for the commercial applications of baker's yeast. This property depends on many factors, such as glycolytic activity, sucrase activity, and osmotolerance. This study explored the importance of sucrase level on the leavening ability of baker's yeast in sweet dough. Furthermore, the baker's yeast strains with varying sucrase activities were constructed by deleting SUC2, which encodes sucrase or replacing the SUC2 promoter with the VPS8/TEF1 promoter. The results verify that the sucrase activity negatively affects the leavening ability of baker's yeast strains under high-sucrose conditions. Based on a certain level of osmotolerance, sucrase level plays a significant role in the fermentation performance of baker's yeast, and appropriate sucrase activity is an important determinant for the leavening property of baker's yeast in sweet dough. Therefore, modification on sucrase activity is an effective method for improving the leavening properties of baker's yeast in sweet dough. This finding provides guidance for the breeding of industrial baker's yeast strains for sweet dough leavening. The transformants BS1 with deleted SUC2 genetic background provided decreased sucrase activity (a decrease of 39.3 %) and exhibited enhanced leavening property (an increase of 12.4 %). Such a strain could be useful for industrial applications.


Subject(s)
Bread/microbiology , Food Handling , Food Microbiology , Saccharomyces cerevisiae/metabolism , Sucrase/metabolism , Biomass , Bread/analysis , Culture Media/chemistry , Fermentation , Gene Deletion , Glucose/analysis , Glycerol/analysis , Peptide Elongation Factor 1/genetics , Peptide Elongation Factor 1/metabolism , Plasmids/genetics , Promoter Regions, Genetic , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Sucrose/analysis , Trehalose/analysis , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolism , beta-Fructofuranosidase/genetics , beta-Fructofuranosidase/metabolism
13.
Zhongguo Zhong Yao Za Zhi ; 41(1): 70-74, 2016 Jan.
Article in Zh | MEDLINE | ID: mdl-28845643

ABSTRACT

To determine the process parameters of optimal water-extraction and ethanol precipitation method for Xuanbi'antong (XBF) extract, which is a clinically experience formula for coronary disease. Orthogonal test L9(34) was conducted for the study of XBF water-extraction and ethanol precipitation process. Extractum, salvianolic acid B, rhizoma coptidis alkaloid, paeoniflorin, puerarin, ginsenoside Rb1, ginsenosides and echinacoside were selected as marker components and multi-index comprehensive weighted score was used to select and verify optimal water-extraction and ethanol precipitation process. The optimal extraction process was as follows: XBF was added with 10 times distilled water, decocted for half an hour for 3 times. The best ethanol-precipitation process was established where the ethanol was added up to 70% and precipitated for 24 hours in 1.12 extract density (20 ℃). The optimized water-extraction and ethanol precipitation method is stable and reliable, and can provide reference for further development and utilization of the formula.


Subject(s)
Chemical Fractionation/methods , Coptis/chemistry , Drugs, Chinese Herbal/isolation & purification , Drugs, Chinese Herbal/chemistry , Ethanol/chemistry , Ginsenosides/chemistry , Ginsenosides/isolation & purification , Glucosides/chemistry , Glucosides/isolation & purification , Monoterpenes/chemistry , Monoterpenes/isolation & purification , Rhizome/chemistry , Water/chemistry
14.
J Ind Microbiol Biotechnol ; 42(6): 939-48, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25877163

ABSTRACT

Dough-leavening ability is one of the main aspects considered when selecting a baker's yeast strain for baking industry. Generally, modification of maltose metabolic pathway and known regulatory networks of maltose metabolism were used to increase maltose metabolism to improve leavening ability in lean dough. In this study, we focus on the effects of PGM2 (encoding for the phosphoglucomutase) and SNR84 (encoding for the H/ACA snoRNA) that are not directly related to both the maltose metabolic pathway and known regulatory networks of maltose metabolism on the leavening ability of baker's yeast in lean dough. The results show that the modifications on PGM2 and/or SNR84 are effective ways in improving leavening ability of baker's yeast in lean dough. Deletion of PGM2 decreased cellular glucose-1-phosphate and overexpression of SNR84 increased the maltose permease activity. These changes resulted in 11, 19 and 21% increases of the leavening ability for PGM2 deletion, SNR84 overexpression and SNR84 overexpression combining deleted PGM2, respectively.


Subject(s)
Bread/microbiology , Carbohydrate Metabolism/genetics , Maltose/metabolism , Phosphoglucomutase/deficiency , RNA, Small Nucleolar/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Food Industry/methods , Gene Deletion , Gene Expression Regulation, Fungal , Genes, Fungal/genetics , Glucosephosphates/metabolism , Monosaccharide Transport Proteins/metabolism , Phosphoglucomutase/genetics , Phosphoglucomutase/metabolism , Saccharomyces cerevisiae/enzymology
15.
J Ind Microbiol Biotechnol ; 42(4): 617-25, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25616436

ABSTRACT

An appropriate level of higher alcohols produced by yeast during the fermentation is one of the most important factors influencing Chinese rice wine quality. In this study, BAT1 and BAT2 single- and double-gene-deletion mutant strains were constructed from an industrial yeast strain RY1 to decrease higher alcohols during Chinese rice wine fermentation. The results showed that the BAT2 single-gene-deletion mutant strain produced best improvement in the production of higher alcohols while remaining showed normal growth and fermentation characteristics. Furthermore, a BAT2 single-gene-deletion diploid engineered strain RY1-Δbat2 was constructed and produced low levels of isobutanol and isoamylol (isoamyl alcohol and active amyl alcohol) in simulated fermentation of Chinese rice wine, 92.40 and 303.31 mg/L, respectively, which were 33.00 and 14.20 % lower than those of the parental strain RY1. The differences in fermentation performance between RY1-Δbat2 and RY1 were minor. Therefore, construction of this yeast strain is important in future development in Chinese wine industry and provides insights on generating yeast strains for other fermented alcoholic beverages.


Subject(s)
Alcohols/metabolism , Fermentation , Gene Deletion , Oryza , Saccharomyces cerevisiae/metabolism , Transaminases/deficiency , Wine , Alcohols/analysis , Butanols/analysis , Butanols/metabolism , Mitochondrial Proteins/deficiency , Mitochondrial Proteins/genetics , Oryza/metabolism , Oryza/microbiology , Pentanols/analysis , Pentanols/metabolism , Saccharomyces cerevisiae/enzymology , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/genetics , Transaminases/genetics , Wine/analysis , Wine/microbiology , Wine/standards
16.
World J Microbiol Biotechnol ; 31(8): 1241-9, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26003653

ABSTRACT

The predominant fermentable sugar in lean dough is maltose. To improve the leavening ability of baker's yeast in lean dough, maltose metabolism should be improved. Maltase (alpha-glucosidase, encoded by MAL62) and maltose permease (encoded by MAL61) are the major factors involved in maltose metabolism. The major rate-limiting factor in maltose metabolism and leavening ability of baker's yeast remains unclear. In this work, MAL61 and/or MAL62 overexpression strains were constructed to investigate the decisive factor for maltose metabolism of industrial baker's yeast in lean dough. Our results show that elevated maltose permease activity by MAL61 overexpression yielded less improvement in maltose fermentation compared to elevated maltase activity by MAL62 overexpression. Significant increase in maltase activity by MAL62 overexpression could result in a 44% increase in leavening ability of industrial baker's yeast in lean dough and a 39% increase in maltose metabolism in a medium containing glucose and maltose. Thus, maltase was the rate-limiting factor in maltose fermentation of industrial baker's yeast in lean dough. This study lays a foundation for breeding of industrial baker's yeast for quick dough leavening.


Subject(s)
Flour/microbiology , Maltose/metabolism , Monosaccharide Transport Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/enzymology , Symporters/metabolism , alpha-Glucosidases/metabolism , Fermentation , Flour/analysis , Monosaccharide Transport Proteins/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Symporters/genetics , alpha-Glucosidases/genetics
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(2): 185-94, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25936707

ABSTRACT

OBJECTIVE: To observe the apoptosis of neural stem cells (NSCs) at differential time points after the dissociation of neurospheres by Accutase or trypsin. METHODS: The NSCs were isolated from striatum of human fetals that suffered abortion at 12-16 weeks of pregnancy. The 3(rd)-5(th) passages of NSCs were digested by Accutase or trypsin. Only vortexing was applied, and the triturating by Pasteur pipette was avoided to attenuate the injury to the cells during the dissociation. The single cells were then stained by Annexin V/propidium iodide and Hoechst 33342. The apoptosis rates 2 and 24 hours after passaging were evaluated. RESULTS: The trypan blue staining confirmed that immediately after the dissociation,the viability of cells digested by trypsin was (83.10 ± 6.76)%, which was significantly lower than that digested by Accutase,which was (91.65 ± 4.43)% (P<0.05). The apoptosis of the NSCs digested by Accutase was higher than that digested by trypsin at both 2 and 24 hours after passaging (P<0.01). Four days after the passaging, both the new clone formation rate and diameter of new spheres after trypsin digestion were significantly higher than those after Accutase digestion (P<0.01). CONCLUSIONS: Although the viability of NSCs immediately after the disassociation by trypsin is lower than that digested by Accutase, the apoptosis of NSCs subsequently caused by trypsin is lower than that caused by Accutase. Trypan blue test immediately after the disassociation can not be used as an indicator in estimating the apoptosis of NSCs during the expanding.


Subject(s)
Apoptosis , Neural Stem Cells , Collagenases , Female , Humans , Neostriatum , Peptide Hydrolases , Pregnancy , Trypsin
18.
Zhongguo Zhong Yao Za Zhi ; 40(8): 1589-93, 2015 Apr.
Article in Zh | MEDLINE | ID: mdl-26281604

ABSTRACT

A study was made on the pharmacokinetic regularity of effective components salvianolic acid B and ferulic acid in Salviae Miltiorrhizae Radix et Rhizoma (SMRR) and Chuanxiong Rhizoma(CR) in rats, so as to discuss the compatibility mechanism of Salviae Miltiorrhizae Radix et Rhizoma and Chuanxiong Rhizoma. Rats were randomly divided into three groups and intravenously injected with 50 mg x kg(-1) salvianolic acid B for the single SMRR extracts group, 0.5 mg x kg(-1) ferulic acid for the single CR extracts group and 50 mg x kg(-1) salvianolic acid B + 0.5 mg x kg(-1) ferulic acid for the SMRR and CR combination group. The blood samples were collected at different time points and purified by liquid-liquid extraction with ethyl acetate. With chloramphenicol as internal standard (IS), UPLC was adopted to determine concentrations of salvianolic acid B and ferulic acid. The pharmacokinetic parameters of salvianolic acid B and ferulic acid were calculated with WinNonlin 6.2 software and analyzed by SPSS 19.0 statistical software. The UPLC analysis method was adopted to determine salvianolic acid B and ferulic acid in rat plasma, including linear equation, stability, repeatability, precision and recovery. The established sample processing and analysis methods were stable and reliable, with significant differences in major pharmacokinetic parameters, e.g., area under the curve (AUC), mean residence time (MRT) and terminal half-life (t(1/2)). According to the experimental results, the combined application of SMRR and CR can significantly impact the pharmacokinetic process of their effective components in rats and promote the wide distribution, shorten the action time and prolong the in vivo action time of salvianolic acid B and increase the blood drug concentration and accelerate the clearance of ferulic acid in vivo.


Subject(s)
Apiaceae/chemistry , Benzofurans/pharmacokinetics , Coumaric Acids/pharmacology , Drugs, Chinese Herbal/pharmacokinetics , Salvia miltiorrhiza/chemistry , Animals , Benzofurans/blood , Coumaric Acids/blood , Drug Interactions , Drugs, Chinese Herbal/analysis , Male , Rats , Rats, Sprague-Dawley , Rhizome/chemistry
19.
Microb Cell Fact ; 13: 93, 2014 Jul 04.
Article in English | MEDLINE | ID: mdl-24993311

ABSTRACT

BACKGROUND: Glucose repression is a global regulatory system in baker's yeast. Maltose metabolism in baker's yeast strains is negatively influenced by glucose, thereby affecting metabolite productivity (leavening ability in lean dough). Even if the general repression system constituted by MIG1, TUP1 and SSN6 factors has already been reported, the functions of these three genes in maltose metabolism remain unclear. In this work, we explored the effects of MIG1 and/or TUP1 and/or SSN6 deletion on the alleviation of glucose-repression to promote maltose metabolism and leavening ability of baker's yeast. RESULTS: Results strongly suggest that the deletion of MIG1 and/or TUP1 and/or SSN6 can exert various effects on glucose repression for maltose metabolism. The deletion of TUP1 was negative for glucose derepression to facilitate the maltose metabolism. By contrast, the deletion of MIG1 and/or SSN6, rather than other double-gene or triple-gene mutations could partly relieve glucose repression, thereby promoting maltose metabolism and the leavening ability of baker's yeast in lean dough. CONCLUSIONS: The mutants of industrial baker's yeast with enhanced maltose metabolism and leavening ability in lean dough were developed by genetic engineering. These baker's yeast strains had excellent potential industrial applications.


Subject(s)
Flour/microbiology , Gene Deletion , Maltose/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Carbon Dioxide/metabolism , Culture Media , Fermentation , Genes, Fungal , Nuclear Proteins/genetics , Repressor Proteins/genetics , Saccharomyces cerevisiae/growth & development , Time Factors , Transformation, Genetic
20.
Biotechnol Appl Biochem ; 61(5): 501-9, 2014.
Article in English | MEDLINE | ID: mdl-24750278

ABSTRACT

Corncob residue, a waste in xylose or xylitol production, was utilized to produce 2,3-butanediol (2,3-BD) via simultaneous saccharification and fermentation (SSF). This study developed the optimal conditions for production of 2,3-BD by using a heat-resistant strain, Enterobacter cloacae UV4, to perform SSF of the corncob residue. Urea, lactic acid, sodium citrate, and MgSO4 , selected by the Plackett-Burman experiment, were determined to be significant independent variables to conduct the response surface experiment. With the optimized medium, a total production of 28.923 g/L for 2,3-BD and acetoin (BA) was obtained at 60 H. Furthermore, 43.162 g/L of BA production and 0.553 g/L/H of productivity were obtained by fed-batch SSF, which was 0.424 g diol/g consumed corncob residue. The results suggest that the waste corncob residue could be used as an available substrate for the production of 2,3-BD by E. cloacae UV4, as well as a potential resource to improve the economics of microbial compound production.


Subject(s)
Batch Cell Culture Techniques/methods , Bioreactors/microbiology , Butylene Glycols/metabolism , Enterobacter cloacae/metabolism , Zea mays/chemistry , Biofuels , Biomass , Culture Media/chemistry , Culture Media/metabolism , Fermentation
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