scholarly journals Ploidy of Bacillus subtilis, Bacillus megaterium, and three new isolates of Bacillus and Paenibacillus

2014 ◽  
Author(s):  
Benjamin Böttinger ◽  
Karolin Zerulla ◽  
Jörg Soppa
Keyword(s):  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Bacillus Megaterium ◽  
Ploidy Level ◽  
Methanogenic Archaea ◽  
Exponential Phase ◽  
Phylogenetic Groups ◽  
Circular Chromosome ◽  
Additional Group ◽  
Positive Genus

Bacteria were long assumed to be monoploid, maintaining one copy of a circular chromosome. In recent years it became obvious that the majority of species in several phylogenetic groups of prokaryotes are oligoploid or polyploid, e.g. in halophilic and methanogenic archaea, proteobacteria, and cyanobacteria. The present study aimed at investigating the distribution of ploidy in an additional group of prokaryotes, i.e. in the gram-positive genus Bacillus. First, the numbers of origins and termini of the two laboratory strains Bacillus subtilis and Bacillus megaterium were quantified using an optimized real time PCR approach. B. subtilis was found to be mero-oligoploid in exponential phase with, on average, 5.9 origins and 1.2 termini. In stationary phase the average numbers of origins per cell was considerably smaller. B. megaterium was found to be polyploid in exponential phase with about 12 copies of the origin and terminus. Again, the ploidy level was down-regulated in stationary phase. To verify that oligo-/polyploidy is not confined to strains with a long history of growth in the laboratory, three strains were newly isolated from soil, which were found to belong to the genera of Bacillus and Paenibacillus. All three strains were found to be oligoploid with a growth-phase dependent down-regulation of the ploidy level in stationary phase. Taken together, these results indicate that oligo-/polyploidy might be more widespread in Bacillus and related genera than assumed until now and that monoploidy is not typical.

scholarly journals Ploidy of Bacillus subtilis, Bacillus megaterium, and three new isolates of Bacillus and Paenibacillus

2014 ◽  
Author(s):  
Benjamin Böttinger ◽  
Karolin Zerulla ◽  
Jörg Soppa
Keyword(s):  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Bacillus Megaterium ◽  
Ploidy Level ◽  
Methanogenic Archaea ◽  
Exponential Phase ◽  
Phylogenetic Groups ◽  
Circular Chromosome ◽  
Additional Group ◽  
Positive Genus

Bacteria were long assumed to be monoploid, maintaining one copy of a circular chromosome. In recent years it became obvious that the majority of species in several phylogenetic groups of prokaryotes are oligoploid or polyploid, e.g. in halophilic and methanogenic archaea, proteobacteria, and cyanobacteria. The present study aimed at investigating the distribution of ploidy in an additional group of prokaryotes, i.e. in the gram-positive genus Bacillus. First, the numbers of origins and termini of the two laboratory strains Bacillus subtilis and Bacillus megaterium were quantified using an optimized real time PCR approach. B. subtilis was found to be mero-oligoploid in exponential phase with, on average, 5.9 origins and 1.2 termini. In stationary phase the average numbers of origins per cell was considerably smaller. B. megaterium was found to be polyploid in exponential phase with about 12 copies of the origin and terminus. Again, the ploidy level was down-regulated in stationary phase. To verify that oligo-/polyploidy is not confined to strains with a long history of growth in the laboratory, three strains were newly isolated from soil, which were found to belong to the genera of Bacillus and Paenibacillus. All three strains were found to be oligoploid with a growth-phase dependent down-regulation of the ploidy level in stationary phase. Taken together, these results indicate that oligo-/polyploidy might be more widespread in Bacillus and related genera than assumed until now and that monoploidy is not typical.

scholarly journals Decreasing Serine Levels During Growth Transition Triggers Biofilm Formation inBacillus subtilis

2019 ◽  
Author(s):  
Jennifer Greenwich ◽  
Alicyn Reverdy ◽  
Kevin Gozzi ◽  
Grace Di Cecco ◽  
Tommy Tashjian ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Biofilm Formation ◽  
Exponential Phase ◽  
Growth Stages ◽  
Translation Rate ◽  
Biofilm Development ◽  
Ribosome Pausing ◽  
Trna Isoacceptors ◽  
Serine Codons

ABSTRACTBiofilm development inBacillus subtilisis regulated at multiple levels. While a number of known signals that trigger biofilm formation do so through the activation of one or more sensory histidine kinases, it was recently discovered that biofilm activation is also coordinated by sensing intracellular metabolic signals, including serine starvation. Serine starvation causes ribosomes to pause on specific serine codons, leading to a decrease in the translation rate ofsinR, which encodes a master repressor for biofilm matrix genes, and ultimately biofilm induction. How serine levels change in different growth stages, howB. subtilisregulates intracellular serine levels in response to metabolic status, and how serine starvation triggers ribosomes to pause on selective serine codons remain unknown. Here we show that serine levels decrease as cells enter stationary phase and that unlike most other amino acid biosynthesis genes, expression of serine biosynthesis genes decreases upon the transition into stationary phase. Deletion of the gene for a serine deaminase responsible for converting serine to pyruvate led to a delay in biofilm formation, further supporting the idea that serine levels are a critical intracellular signal for biofilm activation. Finally, we show that levels of all five serine tRNA isoacceptors are decreased in stationary phase compared to exponential phase. Interestingly, the three isoacceptors recognizing UCN serine codons are reduced to a much greater extent than the two that recognize AGC and AGU serine codons. Our findings provide evidence for a link between serine homeostasis and biofilm development inB. subtilis.IMPORTANCEInBacillus subtilis, biofilm formation is triggered in response to various environmental and cellular signals. It was previously proposed that serine limitation acts as a proxy for nutrient status and triggers biofilm formation at the onset of biofilm entry through a novel signaling mechanism caused by global ribosome pausing on selective serine codons. In this study, we revealed that serine levels decrease at the biofilm entry due to catabolite control and a shunt mechanism. We also show that levels of five serine tRNA isoacceptors are differentially decreased in stationary phase compared to exponential phase; three isoacceptors recognizing UCN serine codons are reduced much greater than the two recognizing AGC and AGU codons. This indicates a possible mechanism for selective ribosome pausing.

scholarly journals An Autoregulatory Circuit Affecting Peptide Signaling in Bacillus subtilis

1999 ◽  
Vol 181 (17) ◽  
pp. 5193-5200 ◽  
Author(s):  
Beth A. Lazazzera ◽  
Iren G. Kurtser ◽  
Ryan S. McQuade ◽  
Alan D. Grossman
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Sigma Factor ◽  
Exponential Phase ◽  
Peptide Signaling ◽  
Expression Of Genes ◽  
Low Concentrations ◽  
Competence And Sporulation Factor

ABSTRACT The competence and sporulation factor (CSF) of Bacillus subtilis is an extracellular pentapeptide produced from the product of phrC. CSF has at least three activities: (i) at low concentrations, it stimulates expression of genes activated by the transcription factor ComA; at higher concentrations, it (ii) inhibits expression of those same genes and (iii) stimulates sporulation. Because the activities of CSF are concentration dependent, we measured the amount of extracellular CSF produced by cells. We found that by mid-exponential phase, CSF accumulated to concentrations (1 to 5 nM) that stimulate ComA-dependent gene expression. Upon entry into stationary phase, CSF reached 50 to 100 nM, concentrations that stimulate sporulation and inhibit ComA-dependent gene expression. Transcription of phrC was found to be controlled by two promoters: P1, which precedes rapC, the gene upstream ofphrC; and P2, which directs transcription ofphrC only. Both RapC and CSF were found to be part of autoregulatory loops that affect transcription from P1, which we show is activated by ComA∼P. RapC negatively regulates its own expression, presumably due to its ability to inhibit accumulation of ComA∼P. CSF positively regulates its own expression, presumably due to its ability to inhibit RapC activity. Transcription from P2, which is controlled by the alternate sigma factor ςH, increased as cells entered stationary phase, contributing to the increase in extracellular CSF at this time. In addition to controlling transcription ofphrC, ςH appears to control expression of at least one other gene required for production of CSF.

scholarly journals Translocation of mycobacillin synthetase in Bacillus subtilis

1985 ◽  
Vol 225 (3) ◽  
pp. 639-643 ◽  
Author(s):  
N K Mukhopadhyay ◽  
S K Ghosh ◽  
S Majumder ◽  
S K Bose
Keyword(s):  
Protein Synthesis ◽  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Exponential Phase ◽  
High Rate ◽  
Synthetase Activity ◽  
Late Exponential Phase ◽  
Extracellular Release ◽  
Particulate Form ◽  
Membrane Bound

The extracellular release of mycobacillin from Bacillus subtilis first occurred in the medium at the onset of stationary phase and continued at a high rate even after 6 days. Mycobacillin synthetase activity appeared earlier than late-exponential phase in the cytosol of producer cells and was not sedimentable even at 105 000 g. The activity then quickly reached the maximum late in the stationary phase. With further increase in the age of the culture, the activity gradually disappeared from the cytosol, to reappear concomitantly in the membrane in an insoluble particulate form, even in absence of protein synthesis. The membrane-bound synthetase activity was sedimentable at 10 000 g and was fairly active even after 5 days.

scholarly journals A Decrease in Serine Levels during Growth Transition Triggers Biofilm Formation inBacillus subtilis

2019 ◽  
Vol 201 (15) ◽  
Author(s):  
Jennifer Greenwich ◽  
Alicyn Reverdy ◽  
Kevin Gozzi ◽  
Grace Di Cecco ◽  
Tommy Tashjian ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Biofilm Formation ◽  
Exponential Phase ◽  
Growth Stages ◽  
Content Type ◽  
Biofilm Development ◽  
Ribosome Pausing ◽  
Trna Isoacceptors ◽  
Serine Codons

ABSTRACTBiofilm development inBacillus subtilisis regulated at multiple levels. While a number of known signals that trigger biofilm formation do so through the activation of one or more sensory histidine kinases, it was discovered that biofilm activation is also coordinated by sensing intracellular metabolic signals, including serine starvation. Serine starvation causes ribosomes to pause on specific serine codons, leading to a decrease in the translation rate ofsinR, which encodes a master repressor for biofilm matrix genes and ultimately triggers biofilm induction. How serine levels change in different growth stages, howB. subtilisregulates intracellular serine levels, and how serine starvation triggers ribosomes to pause on selective serine codons remain unknown. Here, we show that serine levels decrease as cells enter stationary phase and that unlike most other amino acid biosynthesis genes, expression of serine biosynthesis genes decreases upon the transition into stationary phase. The deletion of the gene for a serine deaminase responsible for converting serine to pyruvate led to a delay in biofilm formation, further supporting the idea that serine levels are a critical intracellular signal for biofilm activation. Finally, we show that levels of all five serine tRNA isoacceptors are decreased in stationary phase compared with exponential phase. However, the three isoacceptors recognizing UCN serine codons are reduced to a much greater extent than the two that recognize AGC and AGU serine codons. Our findings provide evidence for a link between serine homeostasis and biofilm development inB. subtilis.IMPORTANCEInBacillus subtilis, biofilm formation is triggered in response to environmental and cellular signals. It was proposed that serine limitation acts as a proxy for nutrient status and triggers biofilm formation at the onset of biofilm entry through a novel signaling mechanism caused by global ribosome pausing on selective serine codons. In this study, we reveal that serine levels decrease at the biofilm entry due to catabolite control and a serine shunt mechanism. We also show that levels of five serine tRNA isoacceptors are differentially decreased in stationary phase compared with exponential phase; three isoacceptors recognizing UCN serine codons are reduced much more than the two recognizing AGC and AGU codons. This finding indicates a possible mechanism for selective ribosome pausing.

scholarly journals Adaptive, or Stationary-Phase, Mutagenesis, a Component of Bacterial Differentiation in Bacillus subtilis

2002 ◽  
Vol 184 (20) ◽  
pp. 5641-5653 ◽  
Author(s):  
Huang-Mo Sung ◽  
Ronald E. Yasbin
Keyword(s):  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Ecological Niche ◽  
Reca Protein ◽  
Exponential Phase ◽  
The Other ◽  
Positive Bacterium ◽  
Bacterial Populations ◽  
Bacterial Differentiation ◽  
Small Subpopulation

ABSTRACT Adaptive (stationary-phase) mutagenesis occurs in the gram-positive bacterium Bacillus subtilis. Furthermore, taking advantage of B. subtilis as a paradigm for the study of prokaryotic differentiation and development, we have shown that this type of mutagenesis is subject to regulation involving at least two of the genes that are involved in the regulation of post-exponential phase prokaryotic differentiation, i.e., comA and comK. On the other hand, a functional RecA protein was not required for this type of mutagenesis. The results seem to suggest that a small subpopulation(s) of the culture is involved in adaptive mutagenesis and that this subpopulation(s) is hypermutable. The existence of such a hypermutable subpopulation(s) raises important considerations with respect to evolution, the development of specific mutations, the nature of bacterial populations, and the level of communication among bacteria in an ecological niche.

Wall turnover deficiency of Bacillus subtilis Nil5 is due to a decrease in teichoic acid

1987 ◽  
Vol 33 (6) ◽  
pp. 566-568 ◽  
Author(s):  
Ljubiša Vitković
Keyword(s):  
Cell Wall ◽  
Bacillus Subtilis ◽  
Stationary Phase ◽  
Phosphorus Content ◽  
Teichoic Acid ◽  
Exponential Phase ◽  
Standard Strain ◽  
Late Exponential Phase ◽  
Wall Teichoic Acid

Bacillus subtilis Ni15 is deficient in cell wall turnover. This deficiency is removed if the medium contains 0.2 M NaCl, which does not affect growth. The levels of amidase and glucosaminidase, the most likely enzymes involved in turnover, were, in stationary phase Nil5 cells, similar to those in late-exponential phase cells of a standard strain. The Nil5 enzymes were not salt sensitive. However, the Nil5 walls contained 4.7-fold less phosphorus than the walls of the standard strain. Since the phosphorus content of B. subtilis walls reflects the level of teichoic acid, it is proposed that the turnover deficiency of this strain is due to a decrease in wall teichoic acid.

scholarly journals Metabolic, Physiological, and Transcriptomics Analysis of Batch Cultures of the Green Microalga Chlamydomonas Grown on Different Acetate Concentrations

Cells ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1367 ◽  
Author(s):  
Bogaert ◽  
Perez ◽  
Rumin ◽  
Giltay ◽  
Carone ◽  
...  
Keyword(s):  
Stationary Phase ◽  
Biomass Yield ◽  
Fatty Acid Content ◽  
Biological Significance ◽  
Exponential Phase ◽  
Low Light ◽  
Batch Mode ◽  
Batch Cultures ◽  
Green Microalga ◽  
Transcriptomics Data

Acetate can be efficiently metabolized by the green microalga Chlamydomonas reinhardtii. The regular concentration is 17 mM, although higher concentrations are reported to increase starch and fatty acid content. To understand the responses to higher acetate concentrations, Chlamydomonas cells were cultivated in batch mode in the light at 17, 31, 44, and 57 mM acetate. Metabolic analyses show that cells grown at 57 mM acetate possess increased contents of all components analyzed (starch, chlorophylls, fatty acids, and proteins), with a three-fold increased volumetric biomass yield compared to cells cultivated at 17 mM acetate at the entry of stationary phase. Physiological analyses highlight the importance of photosynthesis for the low-acetate and exponential-phase samples. The stationary phase is reached when acetate is depleted, except for the cells grown at 57 mM acetate, which still divide until ammonium exhaustion. Surprisal analysis of the transcriptomics data supports the biological significance of our experiments. This allows the establishment of a model for acetate assimilation, its transcriptional regulation and the identification of candidates for genetic engineering of this metabolic pathway. Altogether, our analyses suggest that growing at high-acetate concentrations could increase biomass productivities in low-light and CO2-limiting air-bubbled medium for biotechnology.

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