Molecular Physiological Characterization of a High Heat Resistant Spore Forming Bacillus subtilis Food Isolate

Bacterial endospores (spores) are among the most resistant living forms on earth. Spores of Bacillus subtilis A163 show extremely high resistance to wet heat compared to spores of laboratory strains. In this study, we found that spores of B. subtilis A163 were indeed very wet heat resistant and released dipicolinic acid (DPA) very slowly during heat treatment. We also determined the proteome of vegetative cells and spores of B. subtilis A163 and the differences in these proteomes from those of the laboratory strain PY79, spores of which are much less heat resistant. This proteomic characterization identified 2011 proteins in spores and 1901 proteins in vegetative cells of B. subtilis A163. Surprisingly, spore morphogenic protein SpoVM had no homologs in B. subtilis A163. Comparing protein expression between these two strains uncovered 108 proteins that were differentially present in spores and 93 proteins differentially present in cells. In addition, five of the seven proteins on an operon in strain A163, which is thought to be primarily responsible for this strain’s spores high heat resistance, were also identified. These findings reveal proteomic differences of the two strains exhibiting different resistance to heat and form a basis for further mechanistic analysis of the high heat resistance of B. subtilis A163 spores.

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Challenges and advances in systems biology analysis of Bacillus spore physiology; molecular differences between an extreme heat resistant spore forming Bacillus subtilis food isolate and a laboratory strain

Food Microbiology ◽

10.1016/j.fm.2010.06.011 ◽

2011 ◽

Vol 28 (2) ◽

pp. 221-227 ◽

Cited By ~ 15

Author(s):

Stanley Brul ◽

Johan van Beilen ◽

Martien Caspers ◽

Andrea O’Brien ◽

Chris de Koster ◽

...

Keyword(s):

Bacillus Subtilis ◽

Systems Biology ◽

Laboratory Strain ◽

Extreme Heat ◽

Heat Resistant ◽

Bacillus Spore ◽

Food Isolate

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BEHAVIOR OF A HEAT RESISTANT FOOD SPOILAGE SPORE FORMING ANAEROBE INOCULATED INTO SOILS1,2,3

Journal of Milk and Food Technology ◽

10.4315/0022-2747-17.7.207 ◽

1954 ◽

Vol 17 (7) ◽

pp. 207-213

Author(s):

N. W. Desrosier ◽

W. B. Esselen ◽

E. E. Anderson

Keyword(s):

Heat Resistance ◽

High Heat ◽

Food Spoilage ◽

High Heat Resistance ◽

Heat Resistant ◽

Experimental Soil

The heat resistance of putrefactive spore-forming anaerobes isolated from experimental soil plots was relatively low and not significantly influenced by different fertilizer treatments. The spores of Putrefactive Anaerobe No. 3679 retained their high heat resistance when they were inoculated into the test soils and were subsequently recovered several months later.

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Sorption of water by spores, heat-killed spores, and vegetative cells

Canadian Journal of Microbiology ◽

10.1139/m70-096 ◽

1970 ◽

Vol 16 (7) ◽

pp. 573-579 ◽

Cited By ~ 8

Author(s):

Nicholas Grecz ◽

Roberta F. Smith ◽

Charles C. Hoffmann

Keyword(s):

Heat Resistance ◽

Clostridium Botulinum ◽

High Heat ◽

Bacterial Spores ◽

High Heat Resistance ◽

Closed Chamber ◽

Vegetative Cells ◽

Chemical Inertness ◽

Botulinum Type ◽

Hydrophobic Nature

Several hypotheses explain the heat resistance of bacterial spores in terms of a hydrophobic nature of the spore surface and possibly also the spore interior. The water-sorption properties of naturally hydrated spores which had never been dehydrated before the experiment were studied. The rate of loss of water over P2O5 at 50 °C was measured in a closed chamber by remote weighing with a Cahn electrobalance. The hygroscopicity expressed as percentage of water bound by the sample at aw = 1, 25 °C was as follows.(I) Chemicals:albumin, 70.5; starch, 42.9.(II) Clostridium botulinum 33A, a heat-resistant strain: spores, 47.0; residue (spores heat killed at 121 °C for 30 min), 50.4; exudate (material released from heat-killed spores) 63.1; vegetative cells, 70.3.(III) C. botulinum, type E, strain Beluga, a heat-sensitive strain: spores 62.5; residue, 61.3; exudate, 77.3.It is postulated that molecular masking in the spore is responsible for low binding of water, electrical and chemical inertness, biological dormancy, and high heat resistance of bacterial spores.

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The Products of the spoVA Operon Are Involved in Dipicolinic Acid Uptake into Developing Spores of Bacillus subtilis

Journal of Bacteriology ◽

10.1128/jb.184.2.584-587.2002 ◽

2002 ◽

Vol 184 (2) ◽

pp. 584-587 ◽

Cited By ~ 75

Author(s):

Federico Tovar-Rojo ◽

Monica Chander ◽

Barbara Setlow ◽

Peter Setlow

Keyword(s):

Bacillus Subtilis ◽

Heat Resistance ◽

Dipicolinic Acid ◽

Lytic Enzyme ◽

Acid Uptake ◽

Wild Type ◽

Wet Heat

ABSTRACT Bacillus subtilis cells with mutations in the spoVA operon do not complete sporulation. However, a spoVA strain with mutations that remove all three of the spore’s functional nutrient germinant receptors (termed the ger3 mutations) or the cortex lytic enzyme SleB (but not CwlJ) did complete sporulation. ger3 spoVA and sleB spoVA spores lack dipicolinic acid (DPA) and have lower core wet densities and levels of wet heat resistance than wild-type or ger3 spores. These properties of ger3 spoVA and sleB spoVA spores are identical to those of ger3 spoVF and sleB spoVF spores that lack DPA due to deletion of the spoVF operon coding for DPA synthetase. Sporulation in the presence of exogenous DPA restored DPA levels in ger3 spoVF spores to 53% of the wild-type spore levels, but there was no incorporation of exogenous DPA into ger3 spoVA spores. These data indicate that one or more products of the spoVA operon are involved in DPA transport into the developing forespore during sporulation.

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GEOMETRICAL–TOPOLOGICAL CHARACTERISTICS OF THE SUBSOLIDUS STRUCTURE IN THE MgO – Al2O3 – TiO2 SYSTEM

Bulletin of the National Technical University KhPI Series Chemistry Chemical Technology and Ecology ◽

10.20998/2079-0821.2021.01.03 ◽

2021 ◽

pp. 18-23

Author(s):

Oksana Borysenko ◽

Sergii Logvinkov ◽

Halyna Shabanova ◽

Igor Остапенко ◽

Vita Шумейко

Keyword(s):

Heat Resistance ◽

High Heat ◽

Point Of View ◽

High Heat Resistance ◽

Cubic Crystal ◽

Heat Resistant ◽

Temperature Ranges ◽

Topological Characteristics ◽

Elementary Triangle ◽

Spinel Materials

Among the materials that attract attention from the point of view of creating refractory products with increased heat resistance, one can single out materials based on compositions of the MgO – Al2O3 – TiO2 system. As a result of the thermodynamic analysis of the MgO – Al2O3 – TiO2 system, it was found that the partition of the system into elementary triangles will change in three temperature ranges: I – up to 1537 K, II – in the temperature range 1537 – 2076 K and above 2076 K. It has been established that up to a temperature of 2076 K there is a concentration range of spinel phases: magnesium aluminate spinel – quandylite. Above 1537 K, there is a concentration range: tialite – karroite, which meets the requirements for materials with high heat resistance. The elementary triangle TiO2 – Al2TiO5 – MgTi2O5 can be used to obtain heat–resistant materials based on Al2TiO5 stabilized by MgTi2O5. To obtain heat–resistant periclase–spinel materials, an elementary triangle Mg2TiO4 – MgAl2O4 – MgO is recommended, in which only compounds with a cubic crystal lattice are present. Thus, the division of the MgO – Al2O3 – TiO2 system into elementary triangles and the analysis of the geometrical–topological characteristics of the phases of the system made it possible to select in the system under study the regions of compositions that have optimal properties for obtaining materials with the specified optimal properties.

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Maturation of Released Spores Is Necessary for Acquisition of Full Spore Heat Resistance during Bacillus subtilis Sporulation

Applied and Environmental Microbiology ◽

10.1128/aem.05031-11 ◽

2011 ◽

Vol 77 (19) ◽

pp. 6746-6754 ◽

Cited By ~ 39

Author(s):

Jose-Luis Sanchez-Salas ◽

Barbara Setlow ◽

Pengfei Zhang ◽

Yong-qing Li ◽

Peter Setlow

Keyword(s):

Bacillus Subtilis ◽

Heat Resistance ◽

Uv Radiation ◽

Dipicolinic Acid ◽

Sporulation Medium ◽

Content Type ◽

Dry Heat ◽

Lower Resistance ◽

Wet Heat ◽

Spore Maturation

ABSTRACTThe first ∼10% of spores released from sporangia (early spores) duringBacillus subtilissporulation were isolated, and their properties were compared to those of the total spores produced from the same culture. The early spores had significantly lower resistance to wet heat and hypochlorite than the total spores but identical resistance to dry heat and UV radiation. Early and total spores also had the same levels of core water, dipicolinic acid, and Ca and germinated similarly with several nutrient germinants. The wet heat resistance of the early spores could be increased to that of total spores if early spores were incubated in conditioned sporulation medium for ∼24 h at 37°C (maturation), and some hypochlorite resistance was also restored. The maturation of early spores took place in pH 8 buffer with Ca2+but was blocked by EDTA; maturation was also seen with early spores of strains lacking the CotE protein or the coat-associated transglutaminase, both of which are needed for normal coat structure. Nonetheless, it appears to be most likely that it is changes in coat structure that are responsible for the increased resistance to wet heat and hypochlorite upon early spore maturation.

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The method of purification of N-cyclohexyl maleimide - comonomer for heat-resistant optical methacrylic copolymers

Plasticheskie massy ◽

10.35164/0554-2901-2019-7-8-26-29 ◽

2019 ◽

pp. 26-35

Author(s):

N. Yu. Ladilova ◽

A. V. Zhivoderov ◽

I. Yu. Makarova ◽

M. N. Leshina ◽

P. V. Kornienko ◽

...

Keyword(s):

Heat Resistance ◽

Organic Solvents ◽

Experimental Evaluation ◽

Steam Distillation ◽

High Heat ◽

High Heat Resistance ◽

Main Substance ◽

Heat Resistant ◽

Purification Scheme

Experimental evaluation of various methods for the synthesis of purified N-cyclohexylmaleimide was carried out. It was shown that the monomer obtained by the combined purification scheme, including steam distillation and sequential recrystallization in organic solvents of diff erent polarities, allows to obtain N-cyclohexylmaleimide with the content of the main substance of at least 99.5 wt.% and with a yield of 70–80 wt.%.The monomer synthesized according to the proposed scheme does not contain polymerization-active and coloring impurities. It makes it possible to obtain unpainted methacrylic copolymers on its base with high heat resistance.

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