scholarly journals The Thermotoga maritima Phenotype Is Impacted by Syntrophic Interaction with Methanococcus jannaschii in Hyperthermophilic Coculture

2006 ◽  
Vol 72 (1) ◽  
pp. 811-818 ◽  
Author(s):  
M. R. Johnson ◽  
S. B. Conners ◽  
C. I. Montero ◽  
C. J. Chou ◽  
K. R. Shockley ◽  
...  
Keyword(s):  
Phase Transition ◽  
Stationary Phase ◽  
Growth Phase ◽  
Thermotoga Maritima ◽  
Cell Aggregation ◽  
Differentially Expressed ◽  
Natural Environments ◽  
Glycosyl Hydrolases ◽  
Methanococcus Jannaschii ◽  
Genes Encoding

ABSTRACT Significant growth phase-dependent differences were noted in the transcriptome of the hyperthermophilic bacterium Thermotoga maritima when it was cocultured with the hyperthermophilic archaeon Methanococcus jannaschii. For the mid-log-to-early-stationary-phase transition of a T. maritima monoculture, 24 genes (1.3% of the genome) were differentially expressed twofold or more. In contrast, methanogenic coculture gave rise to 292 genes differentially expressed in T. maritima at this level (15.5% of the genome) for the same growth phase transition. Interspecies H2 transfer resulted in three- to fivefold-higher T. maritima cell densities than in the monoculture, with concomitant formation of exopolysaccharide (EPS)-based cell aggregates. Differential expression of specific sigma factors and genes related to the ppGpp-dependent stringent response suggests involvement in the transition into stationary phase and aggregate formation. Cell aggregation was growth phase dependent, such that it was most prominent during mid-log phase and decayed as cells entered stationary phase. The reduction in cell aggregation was coincidental with down-regulation of genes encoding EPS-forming glycosyltranferases and up-regulation of genes encoding β-specific glycosyl hydrolases; the latter were presumably involved in hydrolysis of β-linked EPS to release cells from aggregates. Detachment of aggregates may facilitate colonization of new locations in natural environments where T. maritima coexists with other organisms. Taken together, these results demonstrate that syntrophic interactions can impact the transcriptome of heterotrophs in methanogenic coculture, and this factor should be considered in examining the microbial ecology in anaerobic environments.

scholarly journals Microarray-Based Characterization of the Listeria monocytogenes Cold Regulon in Log- and Stationary-Phase Cells

2007 ◽  
Vol 73 (20) ◽  
pp. 6484-6498 ◽  
Author(s):  
Yvonne C. Chan ◽  
Sarita Raengpradub ◽  
Kathryn J. Boor ◽  
Martin Wiedmann
Keyword(s):  
Listeria Monocytogenes ◽  
Heat Shock ◽  
Stationary Phase ◽  
Response Regulator ◽  
Differentially Expressed ◽  
Cold Shock Protein ◽  
Rna Helicases ◽  
Transcript Levels ◽  
Number Of Genes ◽  
Genes Encoding

ABSTRACT Whole-genome microarray experiments were performed to define the Listeria monocytogenes cold growth regulon and to identify genes differentially expressed during growth at 4 and 37°C. Microarray analysis using a stringent cutoff (adjusted P < 0.001; ≥2.0-fold change) revealed 105 and 170 genes that showed higher transcript levels in logarithmic- and stationary-phase cells, respectively, at 4°C than in cells grown at 37°C. A total of 74 and 102 genes showed lower transcript levels in logarithmic- and stationary-phase cells, respectively, grown at 4°C. Genes with higher transcript levels at 4°C in both stationary- and log-phase cells included genes encoding a two-component response regulator (lmo0287), a cold shock protein (cspL), and two RNA helicases (lmo0866 and lmo1722), whereas a number of genes encoding virulence factors and heat shock proteins showed lower transcript levels at 4°C. Selected genes that showed higher transcript levels at 4°C during both stationary and log phases were confirmed by quantitative reverse transcriptase PCR. Our data show that (i) a large number of L. monocytogenes genes are differentially expressed at 4 and 37°C, with more genes showing higher transcript levels than lower transcript levels at 4°C, (ii) L. monocytogenes genes with higher transcript levels at 4°C include a number of genes and operons with previously reported or plausible roles in cold adaptation, and (iii) L. monocytogenes genes with lower transcript levels at 4°C include a number of virulence and virulence-associated genes as well as some heat shock genes.

Morphological Characterization of Mycobacteriophage R1

1974 ◽  
Vol 32 ◽  
pp. 254-255
Author(s):  
B. L. Soloff ◽  
T. A. Rado
Keyword(s):  
Carbon Source ◽  
Stationary Phase ◽  
Growth Phase ◽  
Minimal Medium ◽  
Morphological Characterization ◽  
Logarithmic Growth Phase ◽  
Complete Lysis ◽  
Lysogenic Culture ◽  
Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

scholarly journals In vivo transcriptome analysis provides insights into host-dependent expression of virulence factors by Yersinia entomophaga MH96, during infection of Galleria mellonella

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Amber R Paulson ◽  
Maureen O’Callaghan ◽  
Xue-Xian Zhang ◽  
Paul B Rainey ◽  
Mark R H Hurst
Keyword(s):  
Galleria Mellonella ◽  
Functional Enrichment ◽  
Natural Environments ◽  
Insecticidal Toxin ◽  
Heat Stable ◽  
Expression Of Genes ◽  
Genes Encoding ◽  
Cell Densities

Abstract The function of microbes can be inferred from knowledge of genes specifically expressed in natural environments. Here, we report the in vivo transcriptome of the entomopathogenic bacterium Yersinia entomophaga MH96, captured during initial, septicemic, and pre-cadaveric stages of intrahemocoelic infection in Galleria mellonella. A total of 1285 genes were significantly upregulated by MH96 during infection; 829 genes responded to in vivo conditions during at least one stage of infection, 289 responded during two stages of infection, and 167 transcripts responded throughout all three stages of infection compared to in vitro conditions at equivalent cell densities. Genes upregulated during the earliest infection stage included components of the insecticidal toxin complex Yen-TC (chi1, chi2, and yenC1), genes for rearrangement hotspot element containing protein yenC3, cytolethal distending toxin cdtAB, and vegetative insecticidal toxin vip2. Genes more highly expressed throughout the infection cycle included the putative heat-stable enterotoxin yenT and three adhesins (usher-chaperone fimbria, filamentous hemagglutinin, and an AidA-like secreted adhesin). Clustering and functional enrichment of gene expression data also revealed expression of genes encoding type III and VI secretion system-associated effectors. Together these data provide insight into the pathobiology of MH96 and serve as an important resource supporting efforts to identify novel insecticidal agents.

Growth, phase transition, and island motion of Au on Ge(111)

2021 ◽  
Vol 155 (5) ◽  
pp. 054701
Author(s):  
J. A. Giacomo ◽  
C. H. Mullet ◽  
S. Chiang
Keyword(s):  
Phase Transition ◽  
Growth Phase ◽  
Growth Phase Transition

scholarly journals Conversion of Daidzein and Genistein by an Anaerobic Bacterium Newly Isolated from the Mouse Intestine

2008 ◽  
Vol 74 (15) ◽  
pp. 4847-4852 ◽  
Author(s):  
Anastasia Matthies ◽  
Thomas Clavel ◽  
Michael Gütschow ◽  
Wolfram Engst ◽  
Dirk Haller ◽  
...  
Keyword(s):  
Stationary Phase ◽  
Enzyme Induction ◽  
Growth Phase ◽  
Anaerobic Bacterium ◽  
Stationary Growth Phase ◽  
Gut Bacteria ◽  
Soy Isoflavones ◽  
Strictly Anaerobic ◽  
Stationary Growth ◽  
Mouse Intestine

ABSTRACT The metabolism of isoflavones by gut bacteria plays a key role in the availability and bioactivation of these compounds in the intestine. Daidzein and genistein are the most common dietary soy isoflavones. While daidzein conversion yielding equol has been known for some time, the corresponding formation of 5-hydroxy-equol from genistein has not been reported previously. We isolated a strictly anaerobic bacterium (Mt1B8) from the mouse intestine which converted daidzein via dihydrodaidzein to equol as well as genistein via dihydrogenistein to 5-hydroxy-equol. Strain Mt1B8 was a gram-positive, rod-shaped bacterium identified as a member of the Coriobacteriaceae. Strain Mt1B8 also transformed dihydrodaidzein and dihydrogenistein to equol and 5-hydroxy-equol, respectively. The conversion of daidzein, genistein, dihydrodaidzein, and dihydrogenistein in the stationary growth phase depended on preincubation with the corresponding isoflavonoid, indicating enzyme induction. Moreover, dihydrogenistein was transformed even more rapidly in the stationary phase when strain Mt1B8 was grown on either genistein or daidzein. Growing the cells on daidzein also enabled conversion of genistein. This suggests that the same enzymes are involved in the conversion of the two isoflavones.

scholarly journals Function of the Pyruvate Oxidase-Lactate Oxidase Cascade in Interspecies Competition between Streptococcus oligofermentans and Streptococcus mutans

2012 ◽  
Vol 78 (7) ◽  
pp. 2120-2127 ◽  
Author(s):  
Lei Liu ◽  
Huichun Tong ◽  
Xiuzhu Dong
Keyword(s):  
Stationary Phase ◽  
Streptococcus Mutans ◽  
Growth Phase ◽  
Large Degree ◽  
Interspecies Interactions ◽  
Lactate Oxidase ◽  
Interspecies Competition ◽  
Pyruvate Oxidase ◽  
Content Type

ABSTRACTComplex interspecies interactions occur constantly between oral commensals and the opportunistic pathogenStreptococcus mutansin dental plaque. Previously, we showed that oral commensalStreptococcus oligofermentanspossesses multiple enzymes for H2O2production, especially lactate oxidase (Lox), allowing it to out-competeS. mutans. In this study, through extensive biochemical and genetic studies, we identified a pyruvate oxidase (pox) gene inS. oligofermentans. Apoxdeletion mutant completely lost Pox activity, while ectopically expressedpoxrestored activity. Pox was determined to produce most of the H2O2in the earlier growth phase and log phase, while Lox mainly contributed to H2O2production in stationary phase. Bothpoxandloxwere expressed throughout the growth phase, while expression of theloxgene increased by about 2.5-fold when cells entered stationary phase. Since lactate accumulation occurred to a large degree in stationary phase, the differential Pox- and Lox-generated H2O2can be attributed to differential gene expression and substrate availability. Interestingly, inactivation ofpoxcauses a dramatic reduction in H2O2production from lactate, suggesting a synergistic action of the two oxidases in converting lactate into H2O2. In anin vitrotwo-species biofilm experiment, thepoxmutant ofS. oligofermentansfailed to inhibitS. mutanseven thoughloxwas active. In summary,S. oligofermentansdevelops a Pox-Lox synergy strategy to maximize its H2O2formation so as to win the interspecies competition.

scholarly journals Genes Encoding Transcription Factors TaDREB5 and TaNFYC-A7 Are Differentially Expressed in Leaves of Bread Wheat in Response to Drought, Dehydration and ABA

2018 ◽  
Vol 9 ◽  
Author(s):  
Lyudmila Zotova ◽  
Akhylbek Kurishbayev ◽  
Satyvaldy Jatayev ◽  
Gulmira Khassanova ◽  
Askar Zhubatkanov ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Bread Wheat ◽  
Differentially Expressed ◽  
Genes Encoding

scholarly journals Modulation of mRNA Stability Participates in Stationary-Phase-Specific Expression of Ribosome Modulation Factor

2005 ◽  
Vol 187 (6) ◽  
pp. 1951-1958 ◽  
Author(s):  
Toshiko Aiso ◽  
Hideji Yoshida ◽  
Akira Wada ◽  
Reiko Ohki
Keyword(s):  
Stationary Phase ◽  
Growth Phase ◽  
Mrna Stability ◽  
De Novo ◽  
Fresh Medium ◽  
Specific Expression ◽  
Modulation Factor ◽  
Inactive Form ◽  
Regulation Of Growth ◽  
Ribosome Modulation Factor

ABSTRACT The expression of ribosome modulation factor (RMF) is induced during stationary phase in Escherichia coli. RMF participates in the dimerization of 70S ribosomes to form the 100S ribosome, which is the translationally inactive form of the ribosome. To elucidate the involvement of the control of mRNA stability in growth-phase-specific rmf expression, we investigated rmf mRNA stability in stationary-phase cells and cells inoculated into fresh medium. The rmf mRNA was found to have an extremely long half-life during stationary phase, whereas destabilization of this mRNA took place after the culture was inoculated into fresh medium. RMF and 100S ribosomes disappeared from cells 1 min after inoculation. In addition to control by ppGpp-dependent transcription, these results indicate that the modulation of rmf mRNA stability is also involved in the regulation of growth-phase-specific rmf expression. Unexpectedly, the postinoculation degradation of rmf mRNA was suppressed by the addition of rifampin, suggesting that de novo RNA synthesis is necessary for degradation. This degradation was also suppressed in both a poly(A) polymerase-deficient and an rne-131 mutant strain. We cloned and sequenced the 3′-proximal regions of rmf mRNAs and found that most of these 3′ ends terminated at the ρ-independent terminator with the addition of a one- to five-A oligo(A) tail in either stationary-phase or inoculated cells. No difference was observed in the length of the poly(A) tail between stationary-phase and inoculated cells. These results suggest that a certain postinoculation-specific regulatory factor participates in the destabilization of rmf mRNA and is dependent on polyadenylation.

Long-Living Budding Yeast Cell Subpopulation Induced by Ethanol/Acetate and Respiration

2019 ◽  
Vol 75 (8) ◽  
pp. 1448-1456 ◽  
Author(s):  
Young-Yon Kwon ◽  
Seung-Soo Kim ◽  
Han-Jun Lee ◽  
Seo-Hyeong Sheen ◽  
Kyoung Heon Kim ◽  
...  
Keyword(s):  
Differentially Expressed Genes ◽  
Budding Yeast ◽  
Gradient Centrifugation ◽  
Carbon Sources ◽  
Cell Types ◽  
Glucose Sensing ◽  
Differentially Expressed ◽  
Cell Subpopulation ◽  
Genes Encoding ◽  
Cell Transcriptome

Abstract Budding yeast generate heterogeneous cells that can be separated into two distinctive cell types: short-living low-density and long-living high-density (HD) cells by density gradient centrifugation. We found that ethanol and acetate induce formation of HD cells, and mitochondrial respiration is required. From their transcriptomes and metabolomes, we found upregulated differentially expressed genes in HD cells involved in the RGT2/RGT1 glucose sensing pathway and its downstream genes encoding hexose transporters. For HD cells, we determined an abundance of various carbon sources including glucose, lactate, pyruvate, trehalose, mannitol, mannose, and galactose. Other upregulated differentially expressed genes in HD cells were involved in the TORC1–SCH9 signaling pathway and its downstream genes involved in cytoplasmic translation. We also measured an abundance of free amino acids in HD cells including valine, proline, isoleucine, and glutamine. These characteristics of the HD cell transcriptome and metabolome may be important conditions for maintaining a long-living phenotype.

scholarly journals Tyrosine kinases Tie1 and Tie2 are differentially expressed in non-small cell lung cancer.

2020 ◽  
Author(s):  
Shahan Mamoor
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Tyrosine Kinases ◽  
The United States ◽  
Small Cell ◽  
Differentially Expressed ◽  
Small Cell Lung ◽  
Genes Encoding ◽  
Epidermal Growth

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death in the United States (1). We mined published microarray data (2, 3, 4) to identify differentially expressed genes in NSCLC. We found that the genes encoding the tyrosine kinase with immunoglobulin and epidermal growth factor homology domains 1 - Tie1, and its counterpart Tie2 - were both among the genes whose expression was most quantitatively different in tumors from patients with NSCLC as compared to the lung. Tie1 and Tie2 may be important for initiation or progression of non-small cell lung cancer in humans.

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