Temperature shifts and sporulation of Bacillus megaterium

Strnadová, M.; Hecker, Michael; Wölfel, L.; Mach, Hiltraud; Chaloupka, J.

doi:10.1099/00221287-137-4-787

Cited by 17 publications

(9 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Bacillus spp. can synthesize HSPs during growth as well as during sporogenesis (10,15,18), but their presence in sporulating cells cannot increase the temperature permissive for sporulation (16,17). Sporulating cells of B. megaterium were therefore challenged by pulses of supraoptimal temperature (45°C) in various sporulation phases to determine whether spores developed in heat-shocked sporangia incubated subsequently at 27°C would be more heat resistant than control spores.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Heat shock applied early in sporulation affects heat resistance of Bacillus megaterium spores

et al. 1993

View full text Add to dashboard Cite

Cells of Bacillus megaterium 27 were challenged by a 30-min heat shock at 45 degrees C during various sporulation stages and then shifted back to a temperature permissive for sporulation (27 degrees C), at which they developed spores. Heat shock applied at 120 min after the end of the exponential phase induced synthesis of heat shock proteins (HSPs) in the sporangia and delayed the inactivation of spores at 85 degrees C. Several HSPs, mainly HSP 70, could be detected in the cytoplasm of these spores. An analogous HSP, the main HSP induced by increased temperature during growth, belongs to the GroEL group according to its N-terminal sequence. The identity of this protein was confirmed by Western blot (immunoblot) analysis with polyclonal antibodies against B. subtilis GroEL. Sporangia treated by heat shock immediately or 240 min after exponential phase also synthesized HSPs, but none of them could be detected in the spores in an appreciable amount. These spores showed only a slightly increased heat resistance.

show abstract

mentioning

confidence: 99%

“…B. megaterium 27 (4) grew at 27°C in shaken flasks in SYG, a mineral salts medium with glucose (16,17), in which the ammonium chloride concentration was decreased to 0.4 g/liter to become growth limiting. Calcium chloride concentration was 0.111 g/liter.…”

mentioning

confidence: 99%

Heat shock applied early in sporulation affects heat resistance of Bacillus megaterium spores

et al. 1993

View full text Add to dashboard Cite

show abstract

“…The growth was seriously hampered by high temperature especially in the presence of chromate salt. An increased temperature causes changes in membrane composition (Benschoter and Ingram, 1986), imbalance between synthesis and degradation of cellular proteins and ultimately cell death (Strnadova et al, 1991). Adverse effects of high temperature appears to have become aggravated in the presence of chromate, pH is another important environmental factor which controls the growth of microorganisms.…”

Section: Resultsmentioning

confidence: 99%

Hexavalent Chromium Resistant Bacteria from Effluents of Electroplating: Isolation, Characterization and Chromium (VI) Reduction Potential

Sultan¹,

Hasnain²

2000

Pakistan J. of Biological Sciences

View full text Add to dashboard Cite

Ten hexavalent chromium resistant bacterial strains SECr-1, and SECr-10 were isolated horn the effluents of three electroplating units situated in Gujranwala. These bacteria exhibited a very high level of resistance to hexavalent Cr salt and could bear more than 40 mg mlG 1 of potassium chromate in nutrient agar medium. All of them had yellowish white (except SECr-7 which had yellowish brown, SECr-6 and SECr-8 which had off white), convex and circular colonies with entire margins. The cells of these strains were G-ve, motile, aerobic rods. Their morphological and biochemical attributes align them with family Pseudomonadaceae. The optimum temperature for the growth of these bacterial strains was 37EC both in the absence and presence of chromate except SECr-7 fin the absence), SECr-1, SECr-2 and SECr-5 (in the presence of chromate) which yielded maximum growth at 28EC. All of them were capable of growing in wide pH range (pH 5 to pH 9) with maximum growth at pH 7 or 8. However, in the presence of chromate in the medium they preferred alkaline pHs (pH 8 or 9). These bacterial. strains also conferred resistance against salts of other metals and antibiotics. These bacterial strains had great potential for hexavalent chromium reduction and can be exploited for hexavalent chromium detoxification.

show abstract

“…The sporulating strain of B. megaterium 27 and its isogenic asporogenic mutant 27‐36 [10] were used throughout. Cultivation was carried out in growth (SYG) or sporulation (SM) medium [11] in a shaking water bath at 27 or 35±0.5°C, as described in the text. Sporulation was triggered by transferring the population in the late exponential phase (0.8–0.9 mg dry mass ml −1 ) by centrifugation to SM and incubating it at the growth temperature.…”

Section: Methodsmentioning

confidence: 99%

Expression ofdnaKandgroESLoperons during sporulation ofBacillus megaterium

HlavÃ¡Äek

Adamec

Vomastek

et al. 1998

FEMS Microbiology Letters

View full text Add to dashboard Cite

Expression of the dnaK and groEL genes during sporulation was assayed by determination of their mRNA levels by Northern blotting and compared with the relative level and rate of synthesis of the corresponding proteins. The ability of sporulating cells to respond to a heat shock by an increase in dnaK and groEL expression was determined at the same time. Synthesis of DnaK and GroEL encoding mRNAs during sporulation in non‐shocked cells was low suggesting that this kind of cytodifferentiation was not accompanied by enhanced synthesis of these chaperones. Also the ability of sporulating cells to respond to a heat shock by stimulating their synthesis substantially decreased during the reversible and dropped to negligible values during the irreversible sporulation phase. Nevertheless, some dependence of the heat shock response on sporulation exists because sporulation suppression by mutation or by netropsin treatment further decreased the cells' capacity to respond to a heat shock.

show abstract

Temperature shifts and sporulation of Bacillus megaterium

Cited by 17 publications

References 29 publications

Heat shock applied early in sporulation affects heat resistance of Bacillus megaterium spores

Heat shock applied early in sporulation affects heat resistance of Bacillus megaterium spores

Hexavalent Chromium Resistant Bacteria from Effluents of Electroplating: Isolation, Characterization and Chromium (VI) Reduction Potential

Expression ofdnaKandgroESLoperons during sporulation ofBacillus megaterium

Contact Info

Product

Resources

About