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Lyu F, Yang D, Rao L, Liao X. Alanine and glutamate catabolism collaborate to ensure the success of Bacillus subtilis sporulation. Microbiol Res 2024; 286:127828. [PMID: 38991478 DOI: 10.1016/j.micres.2024.127828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 06/30/2024] [Indexed: 07/13/2024]
Abstract
Sporulation as a typical bacterial differentiation process has been studied for decades. However, two crucial aspects of sporulation, (i) the energy sources supporting the process, and (ii) the maintenance of spore dormancy throughout sporulation, are scarcely explored. Here, we reported the crucial role of RocG-mediated glutamate catabolism in regulating mother cell lysis, a critical step for sporulation completion of Bacillus subtilis, likely by providing energy metabolite ATP. Notably, rocG overexpression resulted in an excessive ATP accumulation in sporulating cells, leading to adverse effects on future spore properties, e.g. increased germination efficiency, reduced DPA content, and lowered heat resistance. Additionally, we revealed that Ald-mediated alanine metabolism was highly related to the inhibition of premature germination and the maintenance of spore dormancy during sporulation, which might be achieved by decreasing the typical germinant L-alanine concentration in sporulating environment. Our data inferred that sporulation of B. subtilis was a highly orchestrated biological process requiring a delicate balance in diverse metabolic pathways, hence ensuring both the completion of sporulation and production of high-quality spores.
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Affiliation(s)
- Fengzhi Lyu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China; Key Laboratory of Fruit and Vegetable Processing of Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
| | - Dong Yang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China; Key Laboratory of Fruit and Vegetable Processing of Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
| | - Lei Rao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China; Key Laboratory of Fruit and Vegetable Processing of Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China.
| | - Xiaojun Liao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China; Key Laboratory of Fruit and Vegetable Processing of Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
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2
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Huang Y, Swarge BN, Roseboom W, Bleeker JD, Brul S, Setlow P, Kramer G. Integrative Metabolomics and Proteomics Allow the Global Intracellular Characterization of Bacillus subtilis Cells and Spores. J Proteome Res 2024; 23:596-608. [PMID: 38190553 PMCID: PMC10845140 DOI: 10.1021/acs.jproteome.3c00386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 12/01/2023] [Accepted: 12/08/2023] [Indexed: 01/10/2024]
Abstract
Reliable and comprehensive multi-omics analysis is essential for researchers to understand and explore complex biological systems more completely. Bacillus subtilis (B. subtilis) is a model organism for Gram-positive spore-forming bacteria, and in-depth insight into the physiology and molecular basis of spore formation and germination in this organism requires advanced multilayer molecular data sets generated from the same sample. In this study, we evaluated two monophasic methods for polar and nonpolar compound extraction (acetonitrile/methanol/water; isopropanol/water, and 60% ethanol) and two biphasic methods (chloroform/methanol/water, and methyl tert-butyl ether/methanol/water) on coefficients of variation of analytes, identified metabolite composition, and the quality of proteomics profiles. The 60% EtOH protocol proved to be the easiest in sample processing and was more amenable to automation. Collectively, we annotated 505 and 484 metabolites and identified 1665 and 1562 proteins in B. subtilis vegetative cells and spores, respectively. We also show differences between vegetative cells and spores from a multi-omics perspective and demonstrate that an integrative multi-omics analysis can be implemented from one sample using the 60% EtOH protocol. The results obtained by the 60% EtOH protocol provide comprehensive insight into differences in the metabolic and protein makeup of B. subtilis vegetative cells and spores.
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Affiliation(s)
- Yixuan Huang
- Laboratory
for Mass Spectrometry of Biomolecules, Swammerdam Institute for Life
Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
- Molecular
Biology and Microbial Food Safety, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Bhagyashree N. Swarge
- Laboratory
for Mass Spectrometry of Biomolecules, Swammerdam Institute for Life
Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
- Molecular
Biology and Microbial Food Safety, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Winfried Roseboom
- Laboratory
for Mass Spectrometry of Biomolecules, Swammerdam Institute for Life
Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Jurre D. Bleeker
- Laboratory
for Mass Spectrometry of Biomolecules, Swammerdam Institute for Life
Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Stanley Brul
- Molecular
Biology and Microbial Food Safety, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Peter Setlow
- Department
of Molecular Biology and Biophysics, UConn
Health, Farmington, Connecticut 06030-3305, United States
| | - Gertjan Kramer
- Laboratory
for Mass Spectrometry of Biomolecules, Swammerdam Institute for Life
Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
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3
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Bonaccorsi R, Glass B, Moreno-Paz M, García-Villadangos M, Warren-Rhodes K, Parro V, Manchado JM, Wilhelm MB, McKay CP. In Situ Real-Time Monitoring for Aseptic Drilling: Lessons Learned from the Atacama Rover Astrobiology Drilling Studies Contamination Control Strategy and Implementation and Application to the Icebreaker Mars Life Detection Mission. ASTROBIOLOGY 2023; 23:1303-1336. [PMID: 38133823 DOI: 10.1089/ast.2022.0133] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
In 2019, the Atacama Rover Astrobiology Drilling Studies (ARADS) project field-tested an autonomous rover-mounted robotic drill prototype for a 6-Sol life detection mission to Mars (Icebreaker). ARADS drilled Mars-like materials in the Atacama Desert (Chile), one of the most life-diminished regions on Earth, where mitigating contamination transfer into life-detection instruments becomes critical. Our Contamination Control Strategy and Implementation (CCSI) for the Sample Handling and Transfer System (SHTS) hardware (drill, scoop and funnels) included out-of-simulation protocol testing (out-of-sim) for hardware decontamination and verification during the 6-Sol simulation (in-sim). The most effective five-step decontamination combined safer-to-use sterilants (3%_hydrogen-peroxide-activated 5%_sodium-hypochlorite), and in situ real-time verification by adenosine triphosphate (ATP) and Signs of Life Detector (SOLID) Fluorescence Immunoassay for characterization hardware bioburden and airborne contaminants. The 20- to 40-min protocol enabled a 4-log bioburden reduction down to <0.1 fmoles ATP detection limit (funnels and drill) to 0.2-0.7 fmoles (scoop) of total ATP. The (post-cleaning) hardware background was 0.3 to 1-2 attomoles ATP/cm2 (cleanliness benchmark background values) equivalent to ca. 1-10 colony forming unit (CFU)/cm2. Further, 60-100% of the in-sim hardware background was ≤3-4 bacterial cells/cm2, the threshold limit for Class <7 aseptic operations. Across the six Sols, the flux of airborne contaminants to the drill sites was ∼5 and ∼22 amoles ATP/(cm2·day), accounting for an unexpectedly high Fluorescence Intensity (FI) signal (FI: ∼6000) against aquatic cyanobacteria, but negligible anthropogenic contribution. The SOLID immunoassay also detected microorganisms from multiple habitats across the Atacama Desert (anoxic, alkaline/acidic microenvironments in halite fields, playas, and alluvial fans) in both airborne and post-cleaning hardware background. Finally, the hardware ATP background was 40-250 times lower than the ATP in cores. Similarly, the FI peaks (FImax) against the microbial taxa and molecular biomarkers detected in the post-cleaned hardware (FI: ∼1500-1600) were 5-10 times lower than biomarkers in drilled sediments, excluding significant interference with putative biomarker found in cores. Similar protocols enable the acquisition of contamination-free materials for ultra-sensitive instruments analysis and the integrity of scientific results. Their application can augment our scientific knowledge of the distribution of cryptic life on Mars-like grounds and support life-detection robotic and human-operated missions to Mars.
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Affiliation(s)
- Rosalba Bonaccorsi
- SETI Institute, Mountain View, California, USA
- NASA Ames Research Center, Moffett Field, California, USA
| | - Brian Glass
- NASA Ames Research Center, Moffett Field, California, USA
| | - Mercedes Moreno-Paz
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Madrid, Spain
| | | | - Kimberley Warren-Rhodes
- SETI Institute, Mountain View, California, USA
- NASA Ames Research Center, Moffett Field, California, USA
| | - Victor Parro
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Madrid, Spain
| | - Juan Manuel Manchado
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Madrid, Spain
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Rao L, Zhou B, Serruya R, Moussaieff A, Sinai L, Ben-Yehuda S. Glutamate catabolism during sporulation determines the success of the future spore germination. iScience 2022; 25:105242. [PMID: 36274945 PMCID: PMC9579013 DOI: 10.1016/j.isci.2022.105242] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 07/19/2022] [Accepted: 09/26/2022] [Indexed: 11/30/2022] Open
Abstract
Bacterial spores can preserve cellular dormancy for years, but still hold the remarkable ability to revive and recommence life. This cellular awakening begins with a rapid and irreversible event termed germination; however, the metabolic determinants required for its success have been hardly explored. Here, we show that at the onset of the process of sporulation, the metabolic enzyme RocG catabolizes glutamate, facilitating ATP production in the spore progenitor cell, and subsequently influencing the eventual spore ATP reservoir. Mutants displaying low RocG levels generate low ATP-containing spores that exhibit severe germination deficiency. Importantly, this phenotype could be complemented by expressing RocG at a specific window of time during the initiation of sporulation. Thus, we propose that despite its low abundance in dormant spores, ATP energizes spore germination, and its production, fueled by RocG, is coupled with the initial developmental phase of spore formation.
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Affiliation(s)
- Lei Rao
- The Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, POB 12272, 91120 Jerusalem, Israel
| | - Bing Zhou
- The Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, POB 12272, 91120 Jerusalem, Israel
| | - Raphael Serruya
- The Institute for Drug Research, The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, POB 12272, 91120 Jerusalem, Israel
| | - Arieh Moussaieff
- The Institute for Drug Research, The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, POB 12272, 91120 Jerusalem, Israel
| | - Lior Sinai
- The Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, POB 12272, 91120 Jerusalem, Israel
| | - Sigal Ben-Yehuda
- The Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, POB 12272, 91120 Jerusalem, Israel
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5
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Accumulation and Release of Rare Earth Ions by Spores of Bacillus Species and the Location of These Ions in Spores. Appl Environ Microbiol 2019; 85:AEM.00956-19. [PMID: 31253678 DOI: 10.1128/aem.00956-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 06/20/2019] [Indexed: 12/28/2022] Open
Abstract
Two rare earth ions, Tb3+ and Dy3+, were incorporated into spores of Bacillus species in ≤5 min at neutral pH to 100 to 200 nmol per mg of dry spores, which is equivalent to 2 to 3% of the spore dry weight. The uptake of these ions had, at most, minimal effects on spore wet heat resistance or germination, and the ions were all released upon germination, probably by complex formation with the huge depot of dipicolinic acid (DPA) released when spores germinate. Adsorbed Tb3+/Dy3+ were also released by exogenous DPA within a few minutes and faster than in spore germination. The accumulation of Tb3+/Dy3+ was not reduced in Bacillus subtilis spores by several types of coat defects, significant modification of the spore cortex peptidoglycan structure, specific loss of components of the outer spore crust layer, or the absence of DPA in the spore core. All of these findings are consistent with Tb3+/Dy3+ being accumulated in spores' outer layers, and this was confirmed by transmission electron microscopy. However, the identity of the outer spore components binding the Tb3+/Dy3+ is not clear. These findings provide new information on the adsorption of rare earth ions by Bacillus spores and suggest this adsorption might have applications in capturing rare earth ions from the environment.IMPORTANCE Biosorption of rare earth ions by growing cells of Bacillus species has been well studied and has attracted attention for possible hydrometallurgy applications. However, the interaction of spores from Bacillus species with rare earth ions has not been well studied. We investigated here the adsorption and/or desorption of two rare earth ions, Tb3+ and Dy3+, by Bacillus spores, the location of the adsorbed ions, and the spore properties after ion accumulation. The significant adsorption of rare earth ions on the surfaces of Bacillus spores and the ions' rapid release by a chelator could allow the development of these spores as a biosorbent to recover rare earth ions from the environment.
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Wang F, Song T, Jiang H, Pei C, Huang Q, Xi H. Bacillus subtilis Spore Surface Display of Haloalkane Dehalogenase DhaA. Curr Microbiol 2019; 76:1161-1167. [PMID: 31278426 DOI: 10.1007/s00284-019-01723-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 06/19/2019] [Indexed: 12/18/2022]
Abstract
The haloalkane dehalogenase DhaA can degrade sulfur mustard (2,2'-dichlorethyl sulfide; also known by its military designation HD) in a rapid and environmentally safe manner. However, DhaA is sensitive to temperature and pH, which limits its applications in natural or harsh environments. Spore surface display technology using resistant spores as a carrier to ensure enzymatic activity can reduce production costs and extend the range of applications of DhaA. To this end, we cloned recombinant Bacillus subtilis spores pHY300PLK-cotg-dhaa-6his/DB104(FH01) for the delivery of DhaA from Rhodococcus rhodochrous NCIMB 13064. A dot blotting showed that the fusion protein CotG-linker-DhaA accounted for 0.41% ± 0.03% (P < 0.01) of total spore coat proteins. Immunofluorescence analyses confirmed that DhaA was displayed on the spore surface. The hydrolyzing activity of DhaA displayed on spores towards the HD analog 2-chloroethyl ethylsulfide was 1.74 ± 0.06 U/mL (P < 0.01), with a specific activity was 0.34 ± 0.04 U/mg (P < 0.01). This is the first demonstration that DhaA displayed on the surface of B. subtilis spores retains enzymatic activity, which suggests that it can be used effectively in real-world applications including bioremediation of contaminated environments.
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Affiliation(s)
- Fuli Wang
- Research Institute of Chemical Defense, Academy of Military Sciences, Beijing, 102205, People's Republic of China.,State Key Laboratory of NBC Protection for Civilian, Academy of Military Sciences, Beijing, 102205, People's Republic of China
| | - Tianyu Song
- Research Institute of Chemical Defense, Academy of Military Sciences, Beijing, 102205, People's Republic of China.,State Key Laboratory of NBC Protection for Civilian, Academy of Military Sciences, Beijing, 102205, People's Republic of China
| | - Hui Jiang
- Research Institute of Chemical Defense, Academy of Military Sciences, Beijing, 102205, People's Republic of China.,State Key Laboratory of NBC Protection for Civilian, Academy of Military Sciences, Beijing, 102205, People's Republic of China
| | - Chengxin Pei
- Research Institute of Chemical Defense, Academy of Military Sciences, Beijing, 102205, People's Republic of China.,State Key Laboratory of NBC Protection for Civilian, Academy of Military Sciences, Beijing, 102205, People's Republic of China
| | - Qibin Huang
- Research Institute of Chemical Defense, Academy of Military Sciences, Beijing, 102205, People's Republic of China.,State Key Laboratory of NBC Protection for Civilian, Academy of Military Sciences, Beijing, 102205, People's Republic of China
| | - Hailing Xi
- Research Institute of Chemical Defense, Academy of Military Sciences, Beijing, 102205, People's Republic of China. .,State Key Laboratory of NBC Protection for Civilian, Academy of Military Sciences, Beijing, 102205, People's Republic of China.
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7
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Korza G, Abini-Agbomson S, Setlow B, Shen A, Setlow P. Levels of L-malate and other low molecular weight metabolites in spores of Bacillus species and Clostridium difficile. PLoS One 2017; 12:e0182656. [PMID: 28850573 PMCID: PMC5574573 DOI: 10.1371/journal.pone.0182656] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 07/21/2017] [Indexed: 12/04/2022] Open
Abstract
Dormant spores of Bacillus species lack ATP and NADH and contain notable levels of only a few other common low mol wt energy reserves, including 3-phosphoglyceric acid (3PGA), and glutamic acid. Recently, Bacillus subtilis spores were reported to contain ~ 30 μmol of L-malate/g dry wt, which also could serve as an energy reserve. In present work, L-malate levels were determined in the core of dormant spores of B. subtilis, Bacillus cereus, Bacillus megaterium and Clostridium difficile, using both an enzymatic assay and 13C-NMR on extracts prepared by several different methods. These assays found that levels of L-malate in B. cereus and B. megaterium spores were ≤ 0.5 μmol/g dry wt, and ≤ 1 μmol/g dry wt in B. subtilis spores, and levels of L-lactate and pyruvate in B. megaterium and B. subtilis spores were < 0.5 μmol/g dry wt. Levels of L-malate in C. difficile spores were ≤ 1 μmol/g dry wt, while levels of 3PGA were ~ 7 μmol/g; the latter value was determined by 31P-NMR, and is in between the 3PGA levels in B. megaterium and B. subtilis spores determined previously. 13C-NMR analysis of spore extracts further showed that B. megaterium, B. subtilis and C. difficile contained significant levels of carbonate/bicarbonate in the spore core. Low mol wt carbon-containing small molecules present at > 3 μmol/g dry spores are: i) dipicolinic acid, carbonate/bicarbonate and 3PGA in B. megaterium, B. subtilis and C. difficile; ii) glutamate in B. megaterium and B. subtilis; iii) arginine in B. subtilis; and iv) at least one unidentified compound in all three species.
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Affiliation(s)
- George Korza
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States of America
| | - Stephen Abini-Agbomson
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States of America
| | - Barbara Setlow
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States of America
| | - Aimee Shen
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States of America
| | - Peter Setlow
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States of America
- * E-mail:
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8
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Synchronization of Bacillus subtilis Cells by Spore Germination and Outgrowth. Methods Mol Biol 2016. [PMID: 27815905 DOI: 10.1007/978-1-4939-6603-5_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
This protocol defines conditions under which the germination of spores can be used to synchronize Bacillus subtilis cells, utilizing the time-ordered sequence of events taking place during the transition from spore to vegetative cells. The transition stages involve: phase change, swelling, emergence, initial division, and elongation. By using this method we have obtained two distinctive synchronized cell cycles, while the synchrony faded away in the third cycle. The advantage of using spore outgrowth and germination is that a highly synchronized population of bacterial cells can be obtained. Non-dividing spores stay synchronized, while synchrony rapidly decays during a few divisions. The limitations of this method are that it can be applied only for sporulating bacteria and synchrony lasts for only a limited period of time exceeding not more than two cycles.
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9
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Fan B, Li L, Chao Y, Förstner K, Vogel J, Borriss R, Wu XQ. dRNA-Seq Reveals Genomewide TSSs and Noncoding RNAs of Plant Beneficial Rhizobacterium Bacillus amyloliquefaciens FZB42. PLoS One 2015; 10:e0142002. [PMID: 26540162 PMCID: PMC4634765 DOI: 10.1371/journal.pone.0142002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 10/15/2015] [Indexed: 12/13/2022] Open
Abstract
Bacillus amyloliquefaciens subsp. plantarum FZB42 is a representative of Gram-positive plant-growth-promoting rhizobacteria (PGPR) that inhabit plant root environments. In order to better understand the molecular mechanisms of bacteria-plant symbiosis, we have systematically analyzed the primary transcriptome of strain FZB42 grown under rhizosphere-mimicking conditions using differential RNA sequencing (dRNA-seq). Our analysis revealed 4,877 transcription start sites for protein-coding genes, identified genes differentially expressed under different growth conditions, and corrected many previously mis-annotated genes. We also identified a large number of riboswitches and cis-encoded antisense RNAs, as well as trans-encoded small noncoding RNAs that may play important roles in the gene regulation of Bacillus. Overall, our analyses provided a landscape of Bacillus primary transcriptome and improved the knowledge of rhizobacteria-host interactions.
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Affiliation(s)
- Ben Fan
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, 210037 Nanjing, China
- * E-mail: (BF); (XW)
| | - Lei Li
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, 97080 Würzburg, Germany
| | - Yanjie Chao
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, 97080 Würzburg, Germany
| | - Konrad Förstner
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, 97080 Würzburg, Germany
| | - Jörg Vogel
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, 97080 Würzburg, Germany
| | - Rainer Borriss
- Fachgebiet Phytomedizin, Albrecht Daniel Thaer Institut für Agrar- und Gartenbauwissenschaften, Lebenswissenschaftliche Fakultät, Humboldt Universität zu Berlin, 14195 Berlin, Germany
| | - Xiao-Qin Wu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, 210037 Nanjing, China
- * E-mail: (BF); (XW)
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10
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Abstract
This protocol defines conditions under which the germination of spores can be used to synchronize Bacillus subtilis cells, utilizing the time-ordered sequence of events taking place during the transition from spore to vegetative cells. The transition stages involve: phase change, swelling, emergence, initial division, and elongation. By using this method we have obtained two distinctive synchronized cell cycles, while the synchrony faded away in the third cycle. The advantage of using spore outgrowth and germination is that a highly synchronized population of bacterial cells can be obtained. The limitations of this method are that it can be applied only for sporulating bacteria and synchrony lasts for only a limited period of time exceeding not more than two cycles.
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11
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Yu WB, Gao SH, Yin CY, Zhou Y, Ye BC. Comparative transcriptome analysis of Bacillus subtilis responding to dissolved oxygen in adenosine fermentation. PLoS One 2011; 6:e20092. [PMID: 21625606 PMCID: PMC3097244 DOI: 10.1371/journal.pone.0020092] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 04/12/2011] [Indexed: 12/20/2022] Open
Abstract
Dissolved oxygen (DO) is an important factor for adenosine fermentation. Our previous experiments have shown that low oxygen supply in the growth period was optimal for high adenosine yield. Herein, to better understand the link between oxygen supply and adenosine productivity in B. subtilis (ATCC21616), we sought to systematically explore the effect of DO on genetic regulation and metabolism through transcriptome analysis. The microarrays representing 4,106 genes were used to study temporal transcript profiles of B. subtilis fermentation in response to high oxygen supply (agitation 700 r/min) and low oxygen supply (agitation 450 r/min). The transcriptome data analysis revealed that low oxygen supply has three major effects on metabolism: enhance carbon metabolism (glucose metabolism, pyruvate metabolism and carbon overflow), inhibit degradation of nitrogen sources (glutamate family amino acids and xanthine) and purine synthesis. Inhibition of xanthine degradation was the reason that low oxygen supply enhanced adenosine production. These provide us with potential targets, which can be modified to achieve higher adenosine yield. Expression of genes involved in energy, cell type differentiation, protein synthesis was also influenced by oxygen supply. These results provided new insights into the relationship between oxygen supply and metabolism.
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Affiliation(s)
- Wen-Bang Yu
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Shu-Hong Gao
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Chun-Yun Yin
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Ying Zhou
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Bang-Ce Ye
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
- * E-mail:
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12
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Jeong JW, Snay J, Ataai MM. A mathematical model for examining growth and sporulation processes of Bacillus subtilis. Biotechnol Bioeng 2010; 35:160-84. [PMID: 18592506 DOI: 10.1002/bit.260350208] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A mathematical model for the growth process of the bacterium Bacillus subtilis is described. The model is a highly structured one. The driving motivation for development of the model and explicit accounting of major interactions of metabolic networks in the model is related to our eventual goal that the model will be used in the analysis of complex biological patterns. Bacillus subtilis was chosen in our study due to the interesting sporulation process that these cells undergo in response to adverse environmental conditions including nutrient limitation. Sporulation process in B. subtilis represents a primordial prototype of cellular differentiation in higher cellular systems. Thus a model for the B. subtilis growth process should prove extremely useful for understanding questions of developmental biology. The model is capable of simulating the transition between the exponential and stationary phase of growth in a batch culture. Since during the transition period the growth process and the metabolism become decoupled and many transient processes are taking place, such predictions are a severe test for the validity of any model. A strategy to examine the leading hypothesis on B. subtills sporulation implementing GTP as a component which signals sporulation initiation is described.
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Affiliation(s)
- J W Jeong
- Chemical and Petroleum Engineering Department, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA
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Dodatko T, Akoachere M, Muehlbauer SM, Helfrich F, Howerton A, Ross C, Wysocki V, Brojatsch J, Abel-Santos E. Bacillus cereus spores release alanine that synergizes with inosine to promote germination. PLoS One 2009; 4:e6398. [PMID: 19636427 PMCID: PMC2712684 DOI: 10.1371/journal.pone.0006398] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Accepted: 05/30/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The first step of the bacterial lifecycle is the germination of bacterial spores into their vegetative form, which requires the presence of specific nutrients. In contrast to closely related Bacillus anthracis spores, Bacillus cereus spores germinate in the presence of a single germinant, inosine, yet with a significant lag period. METHODS AND FINDINGS We found that the initial lag period of inosine-treated germination of B. cereus spores disappeared in the presence of supernatants derived from already germinated spores. The lag period also dissipated when inosine was supplemented with the co-germinator alanine. In fact, HPLC-based analysis revealed the presence of amino acids in the supernatant of germinated B. cereus spores. The released amino acids included alanine in concentrations sufficient to promote rapid germination of inosine-treated spores. The alanine racemase inhibitor D-cycloserine enhanced germination of B. cereus spores, presumably by increasing the L-alanine concentration in the supernatant. Moreover, we found that B. cereus spores lacking the germination receptors gerI and gerQ did not germinate and release amino acids in the presence of inosine. These mutant spores, however, germinated efficiently when inosine was supplemented with alanine. Finally, removal of released amino acids in a washout experiment abrogated inosine-mediated germination of B. cereus spores. CONCLUSIONS We found that the single germinant inosine is able to trigger a two-tier mechanism for inosine-mediated germination of B. cereus spores: Inosine mediates the release of alanine, an essential step to complete the germination process. Therefore, B. cereus spores appear to have developed a unique quorum-sensing feedback mechanism to monitor spore density and to coordinate germination.
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Affiliation(s)
- Tetyana Dodatko
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Monique Akoachere
- Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada, United States of America
| | - Stefan M. Muehlbauer
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Forrest Helfrich
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, United States of America
| | - Amber Howerton
- Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada, United States of America
| | - Christian Ross
- School of Life Science, University of Nevada, Las Vegas, Las Vegas, Nevada, United States of America
| | - Vicki Wysocki
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, United States of America
| | - Jürgen Brojatsch
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Ernesto Abel-Santos
- Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada, United States of America
- * E-mail:
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15
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Release of small molecules during germination of spores of Bacillus Species. J Bacteriol 2008; 190:4759-63. [PMID: 18469112 DOI: 10.1128/jb.00399-08] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Free amino acids, dipicolinic acid, and unidentified small molecules were released early in Bacillus spore germination before hydrolysis of the peptidoglycan cortex, but adenine nucleotides and 3-phosphoglycerate were not. These results indicate that early in germination there is a major selective change in the permeability of the spore's inner membrane.
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Furch B, Steinberg C. Extraktion freier Aminosäuren aus Pilzsporen (Phycomyces blakesleeanus). ACTA ACUST UNITED AC 2007. [DOI: 10.1002/jpln.19771400506] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- B. Furch
- Botanischen Institut der Christian‐Albrechts‐Universität Kiel und dem Max Planck Institut für Limnologie
| | - Ch. Steinberg
- Botanischen Institut der Christian‐Albrechts‐Universität Kiel und dem Max Planck Institut für Limnologie
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Vepachedu VR, Setlow P. Role of SpoVA proteins in release of dipicolinic acid during germination of Bacillus subtilis spores triggered by dodecylamine or lysozyme. J Bacteriol 2006; 189:1565-72. [PMID: 17158659 PMCID: PMC1855772 DOI: 10.1128/jb.01613-06] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The release of dipicolinic acid (DPA) during the germination of Bacillus subtilis spores by the cationic surfactant dodecylamine exhibited a pH optimum of approximately 9 and a temperature optimum of 60 degrees C. DPA release during dodecylamine germination of B. subtilis spores with fourfold-elevated levels of the SpoVA proteins that have been suggested to be involved in the release of DPA during nutrient germination was about fourfold faster than DPA release during dodecylamine germination of wild-type spores and was inhibited by HgCl(2). Spores carrying temperature-sensitive mutants in the spoVA operon were also temperature sensitive in DPA release during dodecylamine germination as well as in lysozyme germination of decoated spores. In addition to DPA, dodecylamine triggered the release of amounts of Ca(2+) almost equivalent to those of DPA, and at least one other abundant spore small molecule, glutamic acid, was released in parallel with Ca(2+) and DPA. These data indicate that (i) dodecylamine triggers spore germination by opening a channel in the inner membrane for Ca(2+)-DPA and other small molecules, (ii) this channel is composed at least in part of proteins, and (iii) SpoVA proteins are involved in the release of Ca(2+)-DPA and other small molecules during spore germination, perhaps by being a part of a channel in the spore's inner membrane.
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Affiliation(s)
- Venkata Ramana Vepachedu
- Department of Molecular, Microbial, and Structural Biology, University of Connecticut Health Center, Farmington, CT 06030-3305, USA
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Illades-Aguiar B, Setlow P. Autoprocessing of the protease that degrades small, acid-soluble proteins of spores of Bacillus species is triggered by low pH, dehydration, and dipicolinic acid. J Bacteriol 1994; 176:7032-7. [PMID: 7961468 PMCID: PMC197077 DOI: 10.1128/jb.176.22.7032-7037.1994] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The sequence-specific protease (termed GPR) that degrades small, acid-soluble proteins (SASP) during germination of spores of Bacillus species is synthesized during sporulation as an inactive precursor termed P46. Approximately 2 h later in sporulation, P46 is converted proteolytically to a smaller form, termed P41, which is active in vitro, but which does not act significantly on SASP in vivo until spore germination is initiated. While it appears likely that P46-->P41 conversion is an autoprocessing event, the mechanisms regulating P46-->P41 conversion in vivo are not clear. In this work we found that P46-->P41 conversion in vitro was stimulated tremendously in an allosteric manner by pyridine-2,6-dicarboxylic acid (dipicolinic acid [DPA]) plus Ca2+ but not by Ca2+ in combination with a variety of DPA analogs. The processing reaction stimulated by Ca(2+)-DPA was seen at pH 5.1 but not at pH 6.2 or 7, and under these conditions P46-->P41 conversion exhibited a linear time course and was a first-order reaction, indicative of an intramolecular autoprocessing reaction. At pH 5.1, P46-->P41 conversion was stimulated markedly by very high ionic strength. At pHs from 5.1 to 6.6, P46-->P41 conversion also occurred when P46 was dehydrated to approximately 54% relative humidity. This processing was stimulated markedly when dehydration was carried out in the presence of DPA and NaCl but was greatly decreased when dehydration was to 10, 33, or 75% relative humidity. Since previous work has shown that P(46)-->P(41) processing in vivo takes place (i) after a fall in forespore pH to 6.3 to 6.9 and approximately in parallel with (ii) DPA accumulation by the forespore and (iii) dehydration of the forespore, out new finings in vitro suggest that these three changes may synergistically trigger P(46)-->P(41) autoprocessing in the developing forespore. Presumably the conditions in vivo during this authoprocessing preclude significant attack of the P(41) generated on its SASP substrates.
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Affiliation(s)
- B Illades-Aguiar
- Department of Biochemistry, University of Connecticut Health Center, Farmington 06030
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19
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Jahns T, Kaltwasser H. Purification and properties of a heat-stable and cold-labile NAD-specific glutamate dehydrogenase from Sporosarcina ureae. Arch Microbiol 1994. [DOI: 10.1007/bf00307776] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Jeong J, Ataai MM. A highly structured model for simulation of batch and continuous cultures of B. subtilis and examination of cellular differentiation. Ann N Y Acad Sci 1990; 589:82-90. [PMID: 2113373 DOI: 10.1111/j.1749-6632.1990.tb24236.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- J Jeong
- Department of Chemical Engineering, University of Pittsburgh, Pennsylvania 15261
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Thompson J, Curtis MA, Miller SP. N5-(1-carboxyethyl)-ornithine, a new amino acid from the intracellular pool of Streptococcus lactis. J Bacteriol 1986; 167:522-9. [PMID: 3090017 PMCID: PMC212920 DOI: 10.1128/jb.167.2.522-529.1986] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Intracellular concentrations of amino acids were determined in cells of Streptococcus lactis 133 during growth in complex, spent, and chemically defined media. Glutamic and aspartic acids represented the major constituents of the amino acid pool. However, organisms grown in spent medium or in defined medium supplemented with ornithine also contained unusually high levels of two additional amino acids. One of these amino acids was ornithine. The second compound exhibited properties of a neutral amino acid by coelution with valine from the amino acid analyzer. The compound did not, however, comigrate with valine or any other standard amino acid by two-dimensional thin-layer chromatography. The unknown amino acid was purified by paper and thin-layer chromatography, and its molecular structure was determined by 1H and 13C nuclear magnetic resonance spectroscopy. This new amino acid was shown to be N5-(1-carboxyethyl)-ornithine. The 14C-labeled compound was formed by cells of S. lactis 133 during growth in spent medium or defined medium containing [14C]ornithine. Formation of the derivative by resting cells required ornithine and the presence of a metabolizable sugar. N5-(1-Carboxyethyl)-ornithine was synthesized chemically from both poly-S-ornithine and (2S)-N2-carbobenzyloxy-ornithine as a 1:1 mixture of two diastereomers. The physical and chemical properties of the amino acid purified from S. lactis 133 were identical to those of one of the synthetic diastereomers. The bis-N-trifluoroacetyl-di-n-butyl esters of the natural and synthetic compounds generated identical gas chromatography-mass spectrometry spectra. A mechanism is suggested for the in vivo synthesis of N5-(1-carboxyethyl)-ornithine, and the possible functions of this new amino acid are discussed.
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22
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Ruppen ME, Garner G, Sadoff HL. Protein turnover in Azotobacter vinelandii during encystment and germination. J Bacteriol 1983; 156:1243-8. [PMID: 6643391 PMCID: PMC217974 DOI: 10.1128/jb.156.3.1243-1248.1983] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Protein turnover occurs during differentiation of Azotobacter vinelandii 12837 to the extent of 50% during encystment and 7% during germination. The addition of rifampin at the initiation of encystment prevents encystment and inhibits turnover. In germinating cysts, protein turnover is essential owing to an apparent lack of certain amino acid biosynthetic enzymes. The capacity to synthesize sulfur-containing amino acids from inorganic precursors is regained about halfway through the germination process.
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23
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Neway JO, Switzer RL. Purification, characterization, and physiological function of Bacillus subtilis ornithine transcarbamylase. J Bacteriol 1983; 155:512-21. [PMID: 6409880 PMCID: PMC217718 DOI: 10.1128/jb.155.2.512-521.1983] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
A procedure was developed for purification of ornithine transcarbamylase (OTCase) to near homogeneity from Bacillus subtilis 168. The purified native enzyme existed as a mixture of dimeric, tetrameric, and hexameric forms, but was converted to the dimer in the presence of 2-mercaptoethanol. The molecular weight of the subunit was 44,000. Some general kinetic properties of the enzyme were described. OTCase was repressed by arginine in growing B. subtilis cells, but the enzyme was induced by arginine at the end of exponential growth. Specific antibodies against the purified OTCase were used to show that the same enzyme was produced under all conditions. These results and studies of a mutant lacking OTCase demonstrated that B. subtilis produced only a single OTCase. OTCase was clearly required for arginine biosynthesis, but the physiological function of OTCase induction by arginine was obscure. OTCase was not induced by, or required for, growth on arginine as a carbon and nitrogen source. Absence of OTCase in a mutant did not alter the yield or arginine content of its spores in comparison to a strain containing OTCase.
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24
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Diaz L, Salas J, Hardisson C. Intracellular pool ofStreptomycesspores: Amino acids, nucleosides, adenine nucleotide levels and energy charge. FEMS Microbiol Lett 1983. [DOI: 10.1111/j.1574-6968.1983.tb00545.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Maurizi MR, Switzer RL. Proteolysis in bacterial sporulation. CURRENT TOPICS IN CELLULAR REGULATION 1980; 16:163-224. [PMID: 6772379 DOI: 10.1016/b978-0-12-152816-4.50010-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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27
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Paulus TJ, Switzer RL. Synthesis and inactivation of carbamyl phosphate synthetase isozymes of Bacillus subtilis during growth and sporulation. J Bacteriol 1979; 140:769-73. [PMID: 230177 PMCID: PMC216714 DOI: 10.1128/jb.140.3.769-773.1979] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Pyrimidine-repressible carbamyl phosphate synthetase P was synthesized in parallel with aspartate transcarbamylase during growth of Bacillus subtilis on glucose-nutrient broth. Both enzymes were inactivated at the end of exponential growth, but at different rates and by different mechanisms. Unlike the inactivation of aspartate transcarbamylase, the inactivation of carbamyl phosphate synthetase P was not interrupted by deprivation for oxygen or in a tricarboxylic acid cycle mutant. The arginine-repressible isozyme carbamyl phosphate synthetase A was synthesized in parallel with ornithine transcarbamylase during the stationary phase under these growth conditions. Again, both enzymes were subsequently inactivated, but at different rates and by apparently different mechanisms. The inactivation of carbamyl phosphate synthetase A was not affected in a protease-deficient mutatn the inactivation of ornithine transcarbamylase was greatly slowed.
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28
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Setlow P. Purification and characterization of additional low-molecular-weight basic proteins degraded during germination of Bacillus megaterium spores. J Bacteriol 1978; 136:331-40. [PMID: 101515 PMCID: PMC218665 DOI: 10.1128/jb.136.1.331-340.1978] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dormant spores Bacillus megaterium contained a group of low-molecular-weight (5,000 to 11,000) basic (pI greater than 9.4) proteins (termed D, E, F, and G proteins) which could be extracted from disrupted spores with strong acids. These proteins were distinct from the previously described A, B, and C proteins which are degraded during spore germination. However, the D, E, F, and G proteins were also rapidly degraded during spore germination, accounting for 10 to 15% of the protein degraded. Proteins similar to the D, E, F, and G species were also present in spores of other bacterial species. In B. megaterium, the D, E, F, and G proteins were low or absent (less than 15% of the spore level) in vegetative and young sporulating cells and appeared only late in sporulation. The D, E, F, and G proteins were purified to homogeneity, and all contained a high percentage of hydrophilic amino acids; one protein (G) contained 31% basic amino acids and also contained tryptophan. All four proteins were rapidly degraded in vitro by dormant spore extracts. Two proteins (D and F) were degraded in vitro by the previously described spore protease which initiates degradation of the A, B, and C proteins in vivo; the spore enzyme (s) degrading proteins E and G have not been identified.
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29
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Dills SS, Vary JC. An evaluation of respiration chain-associated functions during initiation of germination of Bacillus megaterium spores. Biochim Biophys Acta Gen Subj 1978; 541:301-11. [PMID: 27232 DOI: 10.1016/0304-4165(78)90190-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In Bacillus megaterium QM B1551, spore germination could be initiated by glucose in the absence of detectable oxygen consumption, ATP synthesis or a pH decrease in the external media, suggesting that none of those reactions were mandatory. In addition, initiation of germination was insensitive to a variety of inhibitors of energy production or protonmotive force uncouplers. Therefore the respiratory chain-associated functions are not prerequisites for initiation of germination but these functions may be necessary to drive energy-dependent transport systems and other biosynthetic reactions during outgrowth.
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Singh RP, Setlow B, Setlow P. Levels of small molecules and enzymes in the mother cell compartment and the forespore of sporulating Bacillus megaterium. J Bacteriol 1977; 130:1130-8. [PMID: 193830 PMCID: PMC235336 DOI: 10.1128/jb.130.3.1130-1138.1977] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We have determined the amounts of a number of small molecules and enzymes in the mother cell compartment and the developing forespore during sporulation of Bacillus megaterium. Significant amounts of adenosine 5'-triphosphate and reduced nicotinamide adenine dinucleotide were present in the forespore compartment before accumulation of dipicolinic acid (DPA), but these compounds disappeared as DPA was accumulated. 3-Phosphoglyceric acid (3-PGA) accumulated only within the developing forespore, beginning 1 to 2 h before DPA accumulation. Throughout its development the forespore contained constant levels of enzymes of both 3-PGA synthesis (phosphoglycerate kinase and glyceraldehyde-3-phosphate dehydrogenase) and 3-PGA utilization (phosphoglycerate mutase, enolase, and pyruvate kinase) at levels similar to those in the mother cell and the dormant spore. Despite the presence of enzymes for 3-PGA utilization, this compound was stable within isolated forespores. Two acid-soluble proteins (A and B proteins) also accumulated only in the forespore, beginning 1 to 2 h before DPA accumulation. At this time the specific protease involved in degradation of the A and B proteins during germination also appeared, but only in the forespore compartment. Nevertheless, the A and B proteins were stable within isolated forespores. Arginine and glutamic acid accumulated within the forespore in parallel with DPA accumulation. The forespore also contained the enzyme arginase at a level similar to that in the mother cell and a level of glutamic acid decarboxylase 2- to 25-fold higher than that in the mother cell, depending on when in sporulation the forespores were isolated. The specific activities of several other enzymes (protease active on hemoglobin, ornithine transcarbamylase, malate dehydrogenase, aconitase, and isocitrate dehydrogenase) in forespores were about 10% or less of the values in the mother cell. Aminopeptidase was present at similar levels in both compartments; threonine deaminase was not found in either compartment.
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Setlow B, Setlow P. Levels of oxidized and reduced pyridine nucleotides in dormant spores and during growth, sporulation, and spore germination of Bacillus megaterium. J Bacteriol 1977; 129:857-65. [PMID: 14113 PMCID: PMC235022 DOI: 10.1128/jb.129.2.857-865.1977] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Dormant spores of Bacillus megaterium contained no detectable reduced nicotinamide adenine dinucleotide (NADH) or reduced nicotinamide adenine dinucleotide phosphate (NADPH) despite significant levels of the oxidized forms of these nucleotides (NAD and NADP). During the first minutes of spore germination there was rapid accumulation of NADH and NADPH. However, this accumulation followed the fall in optical density that is characteristic of the initiation of spore germination. Accumulation of NADH and NADPH early in germination was not blocked by fluoride or cyanide, and it occurred even when germination was carried out in the absence of an exogenous source of reducing power. In addition to pyridine nucleotide reduction, de novo synthesis also began early in germination as the pyridine nucleotide levels increased to those found in growing cells. Midlog-phase cells grown in several different media had 20 to 35 times as much total pyridine nucleotide as did dormant spores. However, as growth and sporulation proceeded, the NADH plus NAD level fell four- to fivefold whereas the NADPH plus NADP level fell by a lesser amount. From min 10 of spore germination until midway through sporulation the value for the ratio of NADH/NAD is about 0.1 (0.03 to 0.18) while the ratio of NADPH/ANDP is about 1.4 (0.3 to 2.4). Comparison of these ratios in log-phase versus stationary phase (sporulation) growth in all three growth media tested did not reveal any common pattern of changes.
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Abstract
As previously found for spores of Bacillus species, dormant spores of Clostridium bifermentans contained essentially no adenosine triphosphate, a high level of adenosine monophosphate, a high level of 3-phosphoglyceric acid, and much transfer ribonucleic acid lacking a 3'-terminal adenosine monophosphate residue. As in spores of Bacillus species, germination of C. bifermentans spores was accompanied by utilization of the 3-phosphoglyceric acid, a large increase in the adenosine triphosphate level, and the disappearance of defective transfer ribonucleic acid. In contrast to spores of Bacillus species, dormant spores of C. bifermentans contained little free amino acid.
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Abstract
L-Malate repressed sporulation in the wild-type strain of Bacillus subtilis. When 75 mM L-malate was added to the growth medium at the time of inoculation, the appearance of heat-resistant spores was delayed 6 to 8 h. The synthesis of extracellular serine protease, alkaline phosphatase, glucose dehydrogenase, and dipicolinic acid was similarly delayed. Sporulation was not repressed when malate was added to the culture at t4 or later. A mutant was selected for ability to sporulate in the presence of malate. This strain could also sporulate in the presence of glucose. The malate-resistant mutant grew poorly with malate as sole carbon source, although it possessed an intact citric acid cycle, and it showed increased levels of malic enzyme. This indicates a defect in the metabolism of malate in the mutant. A mutant lacking malate dehydrogenase activity was also able to sporulate in the presence of malate. A model for the regulation of sporulation by malate is presented and discussed. Citric acid cycle intermediates other than malate did not affect sporulation. In contrast to previous results, sporulation of certain citric acid cycle mutants could be greatly increased or completely restored by the addition of intermediates after the enzymatic block. The results indicate that the failure of citric acid cycle mutants to sporulate can be adequately explained by lack of energy and lack of glutamate.
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Schmit JC, Brody S. Neurospora crassa conidial germination: role of endogenous amino acid pools. J Bacteriol 1975; 124:232-42. [PMID: 170245 PMCID: PMC235887 DOI: 10.1128/jb.124.1.232-242.1975] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The levels of the endogenous amino acid pools in conidia, germinating conidia, and mycelia of wild-type Neurospora crassa were measured. Three different chromatographic procedures employing the amino acid analyzer were used to identify and quantitatively measure 28 different ninhydrin-positive compounds. All of the common amino acids were detected in conidial extracts except proline, methionine, and cystine. The levels of these three amino acid pools were also very low in mycelia. During the first hour of germination in minimal medium, the levels of most of the free amino acid pools decreased. The pool of glutamic acid, the predominant free amino acid in conidia, decreased 70% during the first hour. Very little glutamic acid or any other amino acid was excreted into the medium. During the first 20 min of germination, the decrease in the glutamic acid pool was nearly equivalent to the increase in the aspartic acid pool. The aspartic acid and lambda-aminobutyric acid pools were the only amino acid pools that increased to maximum levels within the first 20 min of germination and then decreased. It is proposed that an important metabolic event that occurs during the early stages of conidial germination is the production of reduced pyridine nucleotides. The degradation of the large glutamic acid pool existing in the conidia (2.5% of the conidial dry weight) could produce these reduced coenzymes.
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Abstract
During initiation of Bacillus megaterium QM B1551 spore germination, trichloroacetic acid-soluble, nondialyzable peptidoglycan fragments with an average molecular weight of 20,000 were excreted. This solubilization of peptidoglycan was measured in vitro as the amount of trichloroacetic acid-soluble hexosamine released from a suspension of broken spores. HgC12, a potent inhibitor of initiation, had no effect on the in vitro solubilization of peptidoglycan. In vivo, HgC12 had no effect on peptidoglycan release from spores that had lost heat resistance, but HgC12 did block complete absorbance loss. These results suggest that mercury inhibits some reactions that normally occur before loss in heat resistance but not the subsequent peptidoglycan release, and mercury inhibits other reactions involved with complete absorbance loss.
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Stastná J, Vinter V. Spores of microorganisms. XXVI. Synthetic activities of germinating spores of Bacillus cereus prevented from outgrowth. Folia Microbiol (Praha) 1975; 20:195-205. [PMID: 806504 DOI: 10.1007/bf02876779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Spores of Bacillus cereus were germinated in a germination limited medium (GL-medium) which facilitates only germination but not the postgerminative development of spores. Under these conditions a limited protein synthesis occurs. However, this protein synthesis is stopped after a short time interval. The rate of synthesis of new proteins, as well as their total amount, is influenced by the length of the activation heat shock. Synthesis of the wall material continues for several hours and thick-walled cells with a changed ultrastructure are formed. Synthesis of the diaminopimelic acid (dap) containing material of the cell wall is sensitive to actinomycin D and relatively resistant to chloramphenicol. Similarly, protein synthesis is relatively chlorapmhenicol-resistant but is fully inhibited by azauracil or spiramycin. Whereas RNA formed in the control culture is partially decomposed after 30 min of incubation, chloramphenicol accelerates its synthesis and prevents its decay. Exudate components apparently stimulate synthesis of ribonucleic acid, proteins and the wall material. The 14-C-dap containing material released by prelabelled spores in the form of the exudate during the germination is not re-utilized by the spores germinated in the GL-medium. The results are discussed with respect to the atypical primary synthetic activities of spores under conditions when the postgerminative development is prevented and from the point of view of participation of the germination exudate during these syntheses.
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Abstract
The regulation of alpha-ketogluterate dehydrogenase, succinate dehydrogenase, fumarase, malate dehydrogenase, and malic enzyme has been studied in Bacillus subitilis. The levels of these enzymes increase rapidly during late exponential phase in a complex medium and are maximal 1 to 2 h after the onset of sporulation. Regulation of enzyme synthesis has been studied in the wild type and different citric acid cycle mutants by adding various metabolites to the growth medium. Alpha-ketoglutarate dehydrogenase is induced by glutamate or alpha-ketoglutarate; succinate dehydrogenase is repressed by malate; and fumarase and malic enzyme are induced by fumarate and malate, respectively. The addition of glucose leads to repression of the citric acid cycle enzymes whereas the level of malic enzyme is unaffected. Studies on the control of enzyme activities in vitro have shown that alpha-ketoglutarate dehydrogenase and succinate dehydrogenase are inhibited by oxalacetate. Enzyme activities are also influenced by the energy level, expressed as the energy charge of the adenylate pool. Isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, and malic enzyme are inhibited at high energy charge values, whereas malate dehydrogenase is inhibited at low energy charge. A survey of the regulation of the citric acid cycle in B.subtilis, based on the present work and previously reported results, is presented and discussed.
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Protein metabolism during germination of Bacillus megaterium spores. I. Protein synthesis and amino acid metabolism. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)41942-x] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Setlow P. Percent charging of transfer ribonucleic acid and levels of ppGpp and pppGpp in dormant and germinated spores of Bacillus megaterium. J Bacteriol 1974; 118:1067-74. [PMID: 4208410 PMCID: PMC246857 DOI: 10.1128/jb.118.3.1067-1074.1974] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The levels of transfer ribonucleic acids (tRNAs) specific for 14 amino acids were almost identical in dormant spores and in spores germinated from 6 to 75 min. Germinated spore tRNAs specific for all amino acids tested were between 63 and 93% charged, and there was no significant change in this value from 6 to 75 min of germination. In contrast, tRNAs isolated from dormant spores specific for nine different amino acids were almost completely(>93%) uncharged. However, some dormant spore tRNAs, i.e., those for arginine, histidine, isoleucine, and valine, showed significant (21 to 72%) levels of aminoacylation. Dormant spores contained no detectable guanosine penta- (pppGpp), tetra- (ppGpp), or triphosphate (GTP). However, these nucleotides appeared in the first minutes of germination, and thereafter all increased in parallel with a ratio of pppGpp plus ppGpp to GTP of 0.07 to 0.11, which is characteristic of unstarved vegetative cells.
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Ohné M. Regulation of aconitase synthesis in Bacillus subtilis: induction, feedback repression, and catabolite repression. J Bacteriol 1974; 117:1295-305. [PMID: 4205196 PMCID: PMC246613 DOI: 10.1128/jb.117.3.1295-1305.1974] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The synthesis of aconitase in Bacillus subtilis wild-type and different citric acid cycle mutants has been studied and the influence of various growth conditions examined. Aconitase is induced by citrate and precursors of citrate and repressed by glutamate. Induction and repression counteract each other, and at equimolar concentrations of citrate and glutamate, aconitase synthesis is unaffected. Induction by citrate can partly overcome catabolite repression of aconitase. Isocitrate dehydrogenase show endogenous induction of aconitase due to citrate accumulation. Leaky mutants defective in citrate synthase and aconitase cannot be induced by citrate, which indicates that they carry a regulatory mutation. The complex regulation of aconitase is discussed with reference to the participation of this enzyme in glutamate biosynthesis and energy metabolism.
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Setlow P, Primus G, Deutscher MP. Absence of 3'-terminal residues from transfer ribonucleic acid of dormant spores of Bacillus megaterium. J Bacteriol 1974; 117:126-32. [PMID: 4202992 PMCID: PMC246533 DOI: 10.1128/jb.117.1.126-132.1974] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Essentially all (>97%) of the transfer ribonucleic acid (tRNA) in log-phase and sporulating cells of Bacillus megaterium contains a complete 3'-cytidyl-cytidyl-adenosine terminus. However, about one-third of the tRNA in the dormant spore lacks the 3'-terminal adenosine 5'-monophosphate (AMP) residue, and some of the adjacent cytosine monophosphate residues are also missing. Examination of specific tRNAs indicated that those specific for isoleucine, leucine, and methionine are missing 30 to 40% of their terminal residue, whereas tRNAs specific for tyrosine lack 88% of the 3'-terminal AMP. Defective spore tRNA is not degraded during germination, but the missing residues are added back in the first minutes of the process. The enzyme catalyzing the addition reaction, tRNA nucleotidyltransferase, is present in the dormant spore at a level similar to that found in the vegetative cell.
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Foerster CW, Foerster HF. Glutamic acid decarboxylase in spores of Bacillus megaterium and its possible involvement in spore germination. J Bacteriol 1973; 114:1090-8. [PMID: 4197264 PMCID: PMC285369 DOI: 10.1128/jb.114.3.1090-1098.1973] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Spores of Bacillus megaterium were examined for glutamic acid decarboxylase (GAD). Although dormant spores showed no GAD activity, spores given sonic treatment and heat-activated spores had high activities when assayed for this enzyme. Several parameters of GAD in heat-activated spores were examined. The effects of KCN, NaN(3), 2,4-dinitrophenol, and KF on GAD activity were examined. Only KCN was an effective inhibitor of GAD activity in heated spores and was also shown to be the only effective inhibitor of GAD activity in vegetative bacteria. Similar patterns of inhibition were obtained with GAD activity and with spore germination, KCN being the only effective inhibitor of both, although at different concentrations. Spore GAD activity in heat-activated spores showed a loss with storage at 4 C; on the other hand, storage at 25 C was not accompanied by a loss, but, to the contrary, showed an increase in GAD activity of about 30%. A comparison of GAD activity at different times during germination, growth, and sporulation showed it to be highest in freshly germinated spores. Although vegetative cells contained GAD activity, the level in log-phase cells was approximately one-half the level obtained with freshly germinated spores. Heat-activated mutant spores with a requirement of gamma-aminobutyric acid for germination gave no GAD activity. GAD activity appeared in mutant spores after germination and increased to levels comparable to parent spores after 9 min of germination.
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Clark VL, Peterson DE, Bernlohr RW. Changes in free amino acid production and intracellular amino acid pools of Bacillus licheniformis as a function of culture age and growth media. J Bacteriol 1972; 112:715-25. [PMID: 5086658 PMCID: PMC251479 DOI: 10.1128/jb.112.2.715-725.1972] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Changes in the endogenous intracellular amino acid pool and total free amino acid production in Bacillus licheniformis grown in minimal media were investigated. The total intracellular pool increased during exponential growth and then decreased rapidly after the end of growth. Most of the amino acids were present at low concentrations, but glutamate and alanine comprised 60 to 90% of the total intracellular free amino acid at most times during the growth cycle. It was concluded that, in addition to providing monomers for protein synthesis, the intracellular amino acid pool may be maintained for the storage of energy-providing metabolic intermediates and possibly as a balance to the ionic strength of the medium. The total free amino acid production by the cell was found to be dependent upon the composition of the salts medium as well as the culture age under conditions in which the carbon and nitrogen sources were the same. A 10-fold increase in extracellular amino acid was observed as the cells changed from vegetative to sporulation metabolism, mostly due to the extrusion of intracellular amino acid. The impact of this increase upon amino acid uptake and pulse-labeling studies using unwashed cells is discussed.
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Abstract
Spore glutamic acid pools were examined in dormant and germinating spores using colorimetric and (14)C analytical procedures. Germination of spores of Bacillus megaterium (parent strain), initiated by d-glucose, was accompanied by a rapid drop in the level of spore pool glutamate, from 12.0 mug/mg of dry spores to 7.7 mug/mg of dry spores after 30 sec of germination. Similar decreases in extractable spore pool glutamate were observed with l-alanine-initiated germination of B. licheniformis spores. On the other hand, glutamate pools of mutant spores of B. megaterium, with a requirement of gamma-aminobutyric acid for spore germination, remained unchanged for 9 min of germination, at which time more than 50% of the spore population had germinated. Evidence for conversion of spore pool glutamate to gamma-aminobutyric acid during germination of spores of B. megaterium (parent strain) was obtained.
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Foerster HF. -aminobutyric acid as a required germinant for mutant spores of Bacillus megaterium. J Bacteriol 1971; 108:817-23. [PMID: 5001872 PMCID: PMC247146 DOI: 10.1128/jb.108.2.817-823.1971] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Germinated spores of Bacillus megaterium QM B1551 were irradiated with ultraviolet light, and spore-forming survivors were screened for germination requirements. Spore strains which failed to germinate in a variety of defined solutions germinative for spores of the parent strain were obtained. Mutant spores germinated readily in solutions containing yeast extract or one of numerous complex preparations. gamma-Aminobutyric acid, obtained from yeast extract by column chromatography, was shown to be required for germination by the mutant spores. gamma-Aminobutyric acid and l-alanine at final concentrations of 1 mm each, in solutions of KI (40 mm), equaled the potency of yeast extract (1 mg/ml) in the germination of the mutant spores. One of several other amino acids could be substituted, though less effectively, for l-alanine. alpha-Aminobutyric acid, beta-aminobutyric acid, beta-alanine, and 5-aminovaleric acid were ineffective substitutes for gamma-aminobutyric acid in mutant spore germination.
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Carstensen EL, Marquis RE, Gerhardt P. Dielectric study of the physical state of electrolytes and water within Bacillus cereus spores. J Bacteriol 1971; 107:106-13. [PMID: 4998245 PMCID: PMC246892 DOI: 10.1128/jb.107.1.106-113.1971] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Dielectric measurements revealed that dormant spores of Bacillus cereus have extremely low conductivities at high frequencies (50 MHz) and so must contain remarkably low concentrations of mobile ions both within the core and in the surrounding integuments. Activation, germination, and outgrowth were all accompanied by increases in conductivity of the cells and their suspending medium, and this result indicated that intracellular electrolytes had become ionized and leaked from the spores. High-frequency dielectric constants of spores were consistent with normal states for cell water. These values increased during successive stages of development from dormant spore to vegetative bacillus, and they could be directly related to increases in cell water content. In all, the results refuted a model of the dormant spore involving freely mobile, ionized electrolytes and supported a model involving electrostatically bound electrolytes.
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