Location of Elements in Ashed Spores of Bacillus megaterium

The effect of calcium on germination of coat-modified Bacillus cereus T spores was investigated. Coat-modified spores produced either by chemical extraction (SDS-DTT-treated spores) or by mutagenesis (10LD mutant spores) were unable to germinate in response to inosine. While SDS-DTT-treated spores could germinate slowly in the presence of L-alanine, l OLD mutant spores could not germinate at all. The lost or reduced germinability of coat-modified spores was restored when exogenous Ca2+ was supplemented to the germination media. The calcium requirement of coat-modified spores for germination was fairly specific. The simultaneous presence of germinant with Ca2+ was also required for germination of coat-modified spores. The optimal recovery of germinability was obsei ved in the presence of 1.0 mm of calcium acetate. The calcium requirement itself was remarkably diminished under the condition in which L-alanine and a certain purine nucleoside analog, adenosine or inosine, coexisted. The lost or diminished germinability observed in SDS-DTT-treated spores or l OLD mutant spores may be attributed to the loss of calcium associated with the spore integuments.

Section: Restoration By Calcium Of L-alanine-induced Germinabilities mentioning

confidence: 99%

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confidence: 99%

See 1 more Smart Citation

Involvement of Calcium in Germination of Coat‐Modified Spores of Bacillus cereus T

Shibata

Miyoshi

Osato

et al. 1992

“…Phosphate which might come from phospho-galactosamine and muramate in the outer coat (5) should be the main strong acidic group of the spore surface, and the negative charge should be neutralized with calcium, magnesium, and other metals, located in the coat of the native spores (6). The increase in germinability of the low P-spores and the Ca-spores, and the decrease in germinability of the acid-washed spores (9) indicate that the negative charge might block the action of ionic germinants and act as a barrier against the initiation of germination.…”

Section: Discussionmentioning

confidence: 99%

Studies on the Bacterial Spore Coat: IX. The Role of Surface Charge in Germination of Bacillus megaterium Spores

Nishihara

Yoshimoto

Kondo

1981

Self Cite

The surface charge of Bacillus megaterium QM B 1551 spores was estimated to be negative, -0.2 and -0.4 t-teq(mg by colloidal titration using glycol chitosan (GCh) and methylglycol chitosan (MGCh), respectively, as positive colloids. MGCh, which reacts with all of the negatively charged groups including carboxylate, inhibited the second stage of the germination to result in semirefractile spores, but GCh, which reacts only with strong acidic groups such as phosphate, did not. The spores produced in a medium with limited phosphate had coats with low phosphate content and carried less negative charge, and they were induced to germinate with 0.4 msr KN03, which is one-tenth of the minimum concentration required for the germination of the control spores. A similar increase in germinability was observed in spores incubated with calcium acetate.. These results suggest that the role of the surface charge in germination is as follows. Strong acidic groups (such as phosphate) in the coat may block the action of ionic germinants and act as a barrier against the initiation of ionic germination. Positively charged compounds (such as calcium) may compensate for this blocking effect. Weak acidic groups (such as carboxylate) may be involved in the later stage of germination.The spore coat, composed of proteins with phosphate, is the outermost layer of Bacillus megaterium spores (5), and is the first contact of the spores with information in their environment, such as germinants. Therefore, the coat has been a subject for the study of the properties of spores, especially the mechanism of germination. On the spore surface are exposed many reactive groups of the coat, including such components as sulfhydryl, hydroxyl, carboxylic, phosphoric, and amino groups. We reported that sulfhydryl and hydroxyl groups might playa role in the recognition of a germinant in the initiation of germination (14). We have now studied the role of the negatively charged groups of the spore surface in germination by using positive colloids for the colloid titration.

“…Following treatment of polymyxin B-treated and gentamicin-treated spores with CaC12 dissociated these antibiotics from the spore coat (6) and reversed their inhibitory effect on growth (13). It is wellknown that bacterial spores contain a large amount of calcium released during germination (8,9). In the present paper, we examined the amount of polymyxin B released from polymyxin B-treated spores upon germination and by treatment with Effect of Polymyxin B on Growth of Germinated Spores and Young Vegetative Cells As polymyxin B did not inhibit the germination of B. subtilis dormant spores, it was considered to act directly on germinated spores.…”

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confidence: 99%

Quantitative Analysis of Polymyxin B Released from Polymyxin B‐Treated Dormant Spores of Bacillus subtilis and Relationship between Its Permeability and Inhibitory Effect on Outgrowth

Fujita-Ichikawa

Tochikubo

1993