scholarly journals Reciprocal hemizygosity analysis reveals that the Saccharomyces cerevisiae CGI121 gene affects lag time duration in synthetic grape must

2021 ◽  
Author(s):  
Runze Li ◽  
Rebecca C Deed
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Low Temperatures ◽  
Lag Time ◽  
Lag Phase ◽  
Phenotypic Traits ◽  
Time Duration ◽  
Phase Duration ◽  
Grape Must ◽  
The Impact ◽  
Reciprocal Hemizygosity Analysis

Abstract It is standard practice to ferment white wines at low temperatures (10-18 °C). However, low temperatures increase fermentation duration and risk of problem ferments, leading to significant costs. The lag duration at fermentation initiation is heavily impacted by temperature; therefore, identification of Saccharomyces cerevisiae genes influencing fermentation kinetics is of interest for winemaking. We selected 28 S. cerevisiae BY4743 single deletants, from a prior list of open reading frames (ORFs) mapped to quantitative trait loci (QTLs) on chromosomes VII and XIII, influencing the duration of fermentative lag time. Five BY4743 deletants, Δapt1, Δcgi121, Δclb6, Δrps17a, and Δvma21, differed significantly in their fermentative lag duration compared to BY4743 in synthetic grape must (SGM) at 15 °C, over 72 h. Fermentation at 12.5 °C for 528 h confirmed the longer lag times of BY4743 Δcgi121, Δrps17a, and Δvma21. These three candidate ORFs were deleted in S. cerevisiae RM11-1a and S288C to perform single reciprocal hemizygosity analysis (RHA). RHA hybrids and single deletants of RM11-1a and S288C were fermented at 12.5 °C in SGM and lag time measurements confirmed that the S288C allele of CGI121 on chromosome XIII, encoding a component of the EKC/KEOPS complex, increased fermentative lag phase duration. Nucleotide sequences of RM11-1a and S288C CGI121 alleles differed by only one synonymous nucleotide, suggesting that intron splicing, codon bias, or positional effects might be responsible for the impact on lag phase duration. This research demonstrates a new role of CGI121 and highlights the applicability of QTL analysis for investigating complex phenotypic traits in yeast.

scholarly journals Reciprocal hemizygosity analysis reveals that the Saccharomyces cerevisiae CGI121 gene affects lag time duration under enological conditions

2020 ◽  
Author(s):  
Runze Li ◽  
Rebecca C. Deed
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Low Temperatures ◽  
Lag Time ◽  
Open Reading Frames ◽  
Lag Phase ◽  
Phenotypic Traits ◽  
Time Duration ◽  
Phase Duration ◽  
The Impact ◽  
Reciprocal Hemizygosity Analysis

Abstract It is standard practice to ferment white wines at low temperatures (10-18ºC). However, low temperatures increase fermentation duration and risk of problem ferments, leading to significant costs. The lag duration at fermentation initiation is heavily impacted by temperature; therefore, identification of Saccharomyces cerevisiae genes impacting on fermentation kinetics is of interest for winemaking.We selected 28 S. cerevisiae BY4743 single deletants, from a prior list of open reading frames (ORFs) mapped to quantitative trait loci (QTLs) on chromosomes VII and XIII, influencing the duration of fermentative lag time. Five BY4743 deletants, Δapt1, Δcgi121, Δclb6, Δrps17a, and Δvma21, differed significantly in their fermentative lag duration compared to BY4743 in synthetic grape medium (SGM) at 15ºC, over 72 h. Fermentation at 12.5ºC for 528 h confirmed the longer lag times of BY4743 Δcgi121, Δrps17a, and Δvma21. These three candidate ORFs were deleted in S. cerevisiae RM11-1a and S288C to perform single reciprocal hemizygosity analysis (RHA). RHA hybrids and single deletants of RM11-1a and S288C were fermented at 12.5ºC in SGM and lag time measurements confirmed that the S288C allele of CGI121 on chromosome XIII, encoding a component of the EKC/KEOPS complex, increased fermentative lag phase duration. Nucleotide sequences of RM11-1a and S288C CGI121 alleles differed by only one synonymous nucleotide, suggesting that codon bias or positional effects might be responsible for the impact on lag phase duration. This research demonstrates a new role of CGI121 and highlights the applicability of QTL analysis for investigating complex phenotypic traits in yeast.

scholarly journals The CGI121 gene from Saccharomyces cerevisiae demonstrates genetic linkage to increased lag time under enological conditions

2020 ◽  
Author(s):  
Runze Li ◽  
Rebecca C. Deed
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Low Temperatures ◽  
Genetic Linkage ◽  
Lag Time ◽  
Lag Phase ◽  
Phenotypic Traits ◽  
Phase Duration ◽  
Fermentation Kinetics ◽  
Lag Times ◽  
The Impact

Abstract Background In winemaking, it is standard practice to ferment white wines at low temperatures (10–18 ºC). However, low temperatures increase the fermentation duration and risk of problem ferments, which can lead to significant costs. The length of the lag period at fermentation initiation is one parameter that is heavily impacted by low temperatures. Therefore, the identification of Saccharomyces cerevisiae genes with an impact on fermentation kinetics, such as lag time, is of interest for winemaking. Results We selected a set of 28 S. cerevisiae BY4743 single deletants based on a prior list of candidate open reading frames (ORFs) mapped to quantitative trait loci (QTLs) on chromosomes VII and XIII influencing the duration of fermentative lag time by bulk segregant analysis. Five out of 28 BY4743 deletants, Δapt1, Δcgi121, Δclb6, Δrps17a, and Δvma21, differed significantly in their fermentative lag phase duration compared to BY4743 in synthetic grape medium (SGM) at 15 ºC, over 72 h. Fermentation at 12.5 ºC for 528 h, to show a greater resolution of the lag times, identified the inability of BY4743 Δapt1 to initiate fermentation and confirmed the significantly longer lag times of the BY4743 Δcgi121, Δrps17a, and Δvma21 deletants. The three candidate ORFs were deleted in S. cerevisiae RM11-1a and S288C to perform single reciprocal hemizygosity analysis (RHA). RHA hybrids and single deletants of RM11-1a and S288C were fermented at 12.5 ºC in SGM. Lag time measurements confirmed genetic linkage of CGI121 on chromosome XIII, encoding a component of the EKC/KEOPS complex, to fermentative lag phase. Nucleotide sequences of RM11-1a and S288C CGI121 alleles differed by only one synonymous nucleotide suggesting that codon bias or positional effects might be responsible for the impact of this gene on lag phase duration. Conclusion This research demonstrates a new role of CGI121 in fermentative lag time in S. cerevisiae during fermentation and highlights the applicability of QTL analysis for investigating complex phenotypic traits in yeast, such as fermentation kinetics.

scholarly journals Bacillus cereuscshAIs Expressed during the Lag Phase of Growth and Serves as a Potential Marker of Early Adaptation to Low Temperature and pH

2019 ◽  
Vol 85 (14) ◽  
Author(s):  
Marina Français ◽  
Frédéric Carlin ◽  
Véronique Broussolle ◽  
Christophe Nguyen-Thé
Keyword(s):  
Cell Division ◽  
Low Temperature ◽  
Promoter Activity ◽  
Lag Time ◽  
The Other ◽  
Lag Phase ◽  
Time Duration ◽  
Content Type ◽  
Sequence Of Events ◽  
Potential Marker

ABSTRACTBacterial adaptation is characterized by a lag phase during which cells do not multiply or modify their physiology to cope with the constraints of their environment. Our aim was to determine a sequence of events during the lag phase of growth at low temperature and pH for threeBacillus cereusstrains. The onsets of expression of two genes, one of which is essential for stress adaptation (cshA, coding for a RNA helicase) and one of which is involved in the transition between lag phase and exponential phase (abrB, coding for a transition regulator), were determined using fluorescent transcriptional reporter systems. Regardless of the stressing conditions and the tested strains, thecshApromoter was active very early, while the biomass increased and always did so before the first cell division. At 12°C and pH 7.0, the onset ofcshApromoter activity occurred at between 3 h and 7 h, while the bacterial counts started to increase at between 12 h and 13 h. At pH 5.0 and at 20°C or 30°C, the onset ofcshApromoter activity occurred before 1 h and earlier than at pH 7.0. In contrast, the onset ofabrBpromoter activity depended on the strain and the stressing conditions. In the ATCC 14579 strain, the onset ofabrBpromoter activity always started at between 30 min and 3 h, before biomass increased and cell division occurred. For the other strains, it took place along with the first cell division at 12°C but did so much later during growth under the other tested conditions.IMPORTANCEThe spore-forming bacteriumB. cereusis a major cause of foodborne outbreaks in Europe. SomeB. cereusstrains can grow at low temperatures and low pH in many processed foods. Modeling of the bacterial lag time is hampered by a lack of knowledge of the timing of events occurring during this phase. In this context, the identification of lag phase markers, not currently available, could be a real advance for the better prediction of lag time duration. Currently, no molecular markers of this phase are available. By determining thatcshAwas always expressed early during the lag phase, we provide a molecular marker of the early adaptation process ofB. cereuscells when exposed to low temperature and pH.

Effect of Glycosaminoglycans on Thrombin- and Atroxin-Induced Fibrin Assembly and Structure

1989 ◽  
Vol 62 (04) ◽  
pp. 1057-1061 ◽  
Author(s):  
Marcus E Carr ◽  
Patrick L Powers
Keyword(s):  
Chondroitin Sulfate ◽  
Fiber Diameter ◽  
Lag Phase ◽  
Low Molecular Weight ◽  
Fibrin Gels ◽  
Fiber Size ◽  
Induced Changes ◽  
The Impact ◽  
Fiber Radius ◽  
Turbidity Increase

SummaryThis study was performed to quantitate the impact of several glycosaminoglycans (GAG) on fibrin assembly and structure. Gel formation was monitored as the increase in optical density at 633 nm subsequent to thrombin (2 NIH u/ml) or atroxin (0.10 mg/ml) addition to solutions of buffered fibrinogen (1 mg/ml) or plasma. Gel absorbance was measured as a function of wavelength (400 to 800 nm) and gel fiber diameter and mass/length ratio (μ) were calculated. Chondroitin sulfate A (CSA)shortened the lag phase, enhanced the maximal rate of turbidity increase, and increased the final gel turbidity of fibrin gels formed by thrombin or atroxin. CSA (16 mg/ml) increased fiber μ from 1.3 to 3.1 × 1013 dalton/cm and fiber radius from 6.0 to 8.6 × 10-6 cm in thrombin-induced gels. μ increased from 0.7 to 2.7 × 1013 dalton/cm and fiber radius from 4 to 7.8 × 10-6 cm for atroxin-induced gels. Above 16 mg/ml, CSA caused fibrinogen precipitation in purified solutions but not in plasma. CSA inhibited thrombin-induced plasma clotting of plasma but effects in atroxin-mediated plasma gels paralleled those seen in purified solutions. Chondroitin sulfate B (CSB)-induced changes in fibrin were similar but slightly less dramatic than those seen with CSA. μ increased from 0.9 to 2.0 × 1013 dalton/cm for thrombin-induced fibrin gels and from 0.8 to 2.3 × 1013 dalton/cm for atroxininduced gels. Low molecular weight heparin (Mr = 5100) slowed fibrin assembly and reduced fiber size by 50% in thrombininduced gels. Changes in μ of atroxin-induced gels were much less pronounced (<20%). This study documents pronounced GAGinduced changes in fibrin structure which vary with GAG species and may mediate significant physiologic functions.

Development and Evaluation of Floating Pulsatile Drug Delivery System Using Meloxicam

2017 ◽  
Vol 7 (04) ◽  
Author(s):  
ShirishaG. Suddala ◽  
S. K. Sahoo ◽  
M. R. Yamsani
Keyword(s):  
Rheumatoid Arthritis ◽  
Drug Delivery ◽  
Drug Release ◽  
Drug Delivery System ◽  
Delivery System ◽  
Lag Time ◽  
Oral Dosage ◽  
Lag Phase ◽  
Pulsatile Drug Delivery

Objective: The objective of this research work was to develop and evaluate the floating– pulsatile drug delivery system (FPDDS) of meloxicam intended for Chrono pharmacotherapy of rheumatoid arthritis. Methods: The system consisting of drug containing core, coated with hydrophilic erodible polymer, which is responsible for a lag phase for pulsatile release, top cover buoyant layer was prepared with HPMC K4M and sodium bicarbonate, provides buoyancy to increase retention of the oral dosage form in the stomach. Meloxicam is a COX-2 inhibitor used to treat joint diseases such as osteoarthritis and rheumatoid arthritis. For rheumatoid arthritis Chrono pharmacotherapy has been recommended to ensure that the highest blood levels of the drug coincide with peak pain and stiffness. Result and discussion: The prepared tablets were characterized and found to exhibit satisfactory physico-chemical characteristics. Hence, the main objective of present work is to formulate FPDDS of meloxicam in order to achieve drug release after pre-determined lag phase. Developed formulations were evaluated for in vitro drug release studies, water uptake and erosion studies, floating behaviour and in vivo radiology studies. Results showed that a certain lag time before drug release which was due to the erosion of the hydrophilic erodible polymer. The lag time clearly depends on the type and amount of hydrophilic polymer which was applied on the inner cores. Floating time and floating lag time was controlled by quantity and composition of buoyant layer. In vivo radiology studies point out the capability of the system of longer residence time of the tablets in the gastric region and releasing the drug after a programmed lag time. Conclusion: The optimized formulation of the developed system provided a lag phase while showing the gastroretension followed by pulsatile drug release that would be beneficial for chronotherapy of rheumatoid arthritis and osteoarthritis.

Studies on Related ms Magnitude Rate Models in Triangular Wave Unloading Section of Calcium Medium-Fine Sandstone

2010 ◽  
Vol 152-153 ◽  
pp. 164-170
Author(s):  
Jie Liu ◽  
Jian Lin Li ◽  
Ying Xia Li ◽  
Shan Shan Yang ◽  
Ji Fang Zhou ◽  
...  
Keyword(s):  
Mechanical Response ◽  
Strain Curve ◽  
Experimental System ◽  
Constant Term ◽  
Lag Time ◽  
Vertical Force ◽  
Time Segment ◽  
Triangular Wave ◽  
Apparent Modulus ◽  
The Impact

Specific to the improvement in the present research of mechanical response under cyclic loading, this paper, taking the calcareous middle- coarse sandstone as the research subject and the RMT-150C experimental system in which data is recoded by ms magnitude as the platform, develops several related models concerning the unloading rate of triangle waves. The unloading process is divided into lag time segment and non-lag time segment, with criterions and related parameters provided as well. The term apparent elastic modulus is defined. The test data analysis shows that there exist a linear relationship between the apparent modulus and instant vertical force before load damage in non-lag time segment. On the preceding basis, a rate-dependent model of triangular wave un-installation section in non-lag time segment is established. Due to the inability of the loading equipment to accurately input the triangle wave, the average loading rate is amended and a constant term is added into it. The model is proved to be reliable, as the predicted value of the deformation rate and the stress strain curve coincides with measured value. At the same time, the impact of the lag time is pointed out quantitatively and a predication model of lag time segment is set up.

scholarly journals Whole-genome sequencing from the New Zealand Saccharomyces cerevisiae population reveals the genomic impacts of novel microbial range expansion

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Peter Higgins ◽  
Cooper A Grace ◽  
Soon A Lee ◽  
Matthew R Goddard
Keyword(s):  
Saccharomyces Cerevisiae ◽  
New Zealand ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Range Expansion ◽  
Copy Number ◽  
Small Scale ◽  
Whole Genome ◽  
Copy Number Changes ◽  
The Impact

Abstract Saccharomyces cerevisiae is extensively utilized for commercial fermentation, and is also an important biological model; however, its ecology has only recently begun to be understood. Through the use of whole-genome sequencing, the species has been characterized into a number of distinct subpopulations, defined by geographical ranges and industrial uses. Here, the whole-genome sequences of 104 New Zealand (NZ) S. cerevisiae strains, including 52 novel genomes, are analyzed alongside 450 published sequences derived from various global locations. The impact of S. cerevisiae novel range expansion into NZ was investigated and these analyses reveal the positioning of NZ strains as a subgroup to the predominantly European/wine clade. A number of genomic differences with the European group correlate with range expansion into NZ, including 18 highly enriched single-nucleotide polymorphism (SNPs) and novel Ty1/2 insertions. While it is not possible to categorically determine if any genetic differences are due to stochastic process or the operations of natural selection, we suggest that the observation of NZ-specific copy number increases of four sugar transporter genes in the HXT family may reasonably represent an adaptation in the NZ S. cerevisiae subpopulation, and this correlates with the observations of copy number changes during adaptation in small-scale experimental evolution studies.

scholarly journals Predictive Modeling for the Growth of Salmonella spp. in Liquid Egg White and Application of Scenario-Based Risk Estimation

2021 ◽  
Vol 9 (3) ◽  
pp. 486
Author(s):  
Mi Seon Kang ◽  
Jin Hwa Park ◽  
Hyun Jung Kim
Keyword(s):  
Predictive Model ◽  
Scenario Analysis ◽  
Specific Growth ◽  
Risk Estimation ◽  
Egg White ◽  
Lag Phase ◽  
Salmonella Spp ◽  
Baseline Model ◽  
Phase Duration ◽  
Root Model

The objective of the study was to develop a predictive model of Salmonella spp. growth in pasteurized liquid egg white (LEW) and to estimate the salmonellosis risk using the baseline model and scenario analysis. Samples were inoculated with six strains of Salmonella, and bacterial growth was observed during storage at 10–37 °C. The primary models were developed using the Baranyi model for LEW. For the secondary models, the obtained specific growth rate (μmax) and lag phase duration were fitted to a square root model and Davey model, respectively, as functions of temperature (R2 ≥ 0.98). For μmax, the values were satisfied within an acceptable range (Af, Bf: 0.70–1.15). The probability of infection (Pinf) due to the consumption of LEW was zero in the baseline model. However, scenario analysis suggested possible salmonellosis for the consumption of LEW. Because Salmonella spp. proliferated much faster in LEW than in egg white (EW) during storage at 20 and 30 °C (p < 0.01), greater Pinf may be obtained for LEW when these products are stored at the same conditions. The developed predictive model can be applied to the risk management of Salmonella spp. along the food chain, including during product storage and distribution.

scholarly journals Biomethane Potential of Sludges from a Brackish Water Fish Hatchery

2021 ◽  
Vol 11 (2) ◽  
pp. 552
Author(s):  
Francesco da Borso ◽  
Alessandro Chiumenti ◽  
Giulio Fait ◽  
Matia Mainardis ◽  
Daniele Goi
Keyword(s):  
Brackish Water ◽  
Gompertz Model ◽  
Experimental Tests ◽  
Lag Phase ◽  
Phase Duration ◽  
Fish Hatchery ◽  
Volatile Solids ◽  
Water Recirculation ◽  
Methane Potential ◽  
Intensive Aquaculture

The development of intensive aquaculture is facing the challenge of the sustainable management of effluents. The reproductive sectors (i.e., hatcheries) mainly use water recirculation systems (RAS), which discharge a portion of wastewater. Anaerobic digestion (AD) could reduce the environmental impact of this waste stream while producing biogas. The study is focused on the biochemical methane potential (BMP) of brackish fish hatchery sludges. Wastewater was concentrated by microfiltration and sedimentation and thickened sludges were treated in a BMP system with different inoculum/substrate (I/S) volatile solids ratios (from 50:1 to no inoculum). The highest I/S ratio showed the highest BMP (564.2 NmL CH4/g VS), while different I/S ratios showed a decreasing trend (319.4 and 127.7 NmL CH4/g VS, for I/S = 30 and I/S = 3). In absence of inoculum BMP resulted of 62.2 NmL CH4/g VS. The kinetic analysis (modified Gompertz model) showed a good correlation with the experimental data, but with a long lag-phase duration (from 14.0 to 5.5 days) in particular with the highest I/S. AD applied to brackish water sludges can be a promising treatment with interesting methane productions. For a continuous, full-scale application further investigation on biomass adaptation to salinity and on retention times is needed. Further experimental tests are ongoing.

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