scholarly journals A Viable Bacillus subtilis Strain without Functional Extracytoplasmic Function Sigma Genes

2008 ◽  
Vol 190 (7) ◽  
pp. 2633-2636 ◽  
Author(s):  
Kei Asai ◽  
Keisuke Ishiwata ◽  
Kunihiko Matsuzaki ◽  
Yoshito Sadaie

ABSTRACT We constructed a Bacillus subtilis Marburg strain that harbors deletion mutations in all seven extracytoplasmic function (ECF) sigma genes. The strain shows wild-type growth at 37°C both in a complex and in a synthetic medium and exhibits wild-type sporulation. ECF sigma genes of B. subtilis are dispensable as long as no stress is imposed, although they seem to be required for quick response to stresses.

Microbiology ◽  
2004 ◽  
Vol 150 (6) ◽  
pp. 1839-1849 ◽  
Author(s):  
Daria Julkowska ◽  
Michal Obuchowski ◽  
I. Barry Holland ◽  
Simone J. Séror

After optimizing the conditions, including nutrients and temperature, swarming of Bacillus subtilis 3610 was obtained on a synthetic, fully defined medium. The swarms formed highly branched (dendritic) patterns, generated by successive waves of moving cells. A detailed microscopic in situ analysis of swarms 1 and 2 revealed varied cell morphologies and a remarkable series of events, with cells assembling into different ‘structures’, as the architecture of the swarm developed. Long filamentous cells begin to form before the onset of the first swarming (11 h) and are again observed at later stages in the interior of individual mature dendrites. Swarm 2, detected at 18–22 h, is accompanied by the rapid movement of a wave of dispersed (non-filamentous) cells. Subsequently at the forward edge of this swarm, individual cells begin to cluster together, gradually forming de novo the shape of a dendrite tip with progressive lengthening of this new structure ‘backwards' towards the swarm centre. In both swarms 1 and 2, after the initial clustering of cells, there is the progressive appearance of a spreading monolayer of rafts (4–5 non-filamented cells, neatly aligned). The alternative possible roles of the rafts in the development of the swarm are discussed.


2021 ◽  
Vol 2(26) ◽  
pp. 28-40
Author(s):  
Z.A. Akhtyamova ◽  
◽  
T.N. Arkhipova ◽  
E.V. Martynenko ◽  
T.V. Nuzhnaya ◽  
...  

The ability to produce phytohormones and influence their metabolism in plants is an important property of rhizosphere bacteria that determines their plant growth promoting effect. Since abscisic acid (ABA) reduces stomatal conductance and increases the ability of tissues to conduct water, maintenance of water balance in lettuce plants on the background of activation of their growth was associated with the accumulation of ABA under the influence of bacteria. The aim of the study is to test the hypothesis that the growth-stimulating effect of bacteria on plants depends on their ability to synthesize the hormone ABA. The plants were grown on a light platform; seedlings were treated with a bacterial suspension simultaneously with planting. The ABA content, the relative water content, the chlorophyll content, the level of non-photochemical quenching, the leaf area and the weight of the shoots were measured. The level of transcripts of the HvNCED1, HvNCED2, and HvCYP707A1 genes responsible for ABA metabolism in barley was assessed using real-time PCR. Comparison of the ABA-deficient mutant of barley and plants of its wild type revealed the stimulation of the growth of plants of both genotypes upon bacterial treatment. The shoot mass and leaf area of the untreated mutant with bacteria were about 30 % less compared to Steptoe. The stimulating effect of bacteria was manifested in an increase in leaf area by 15 % in Steptoe and by 35 % in Az 34; shoot mass – by 18 % and 41 %, respectively. As a result, the phenotype difference between plants of two genotypes decreased. In the deficient mutant, the ABA level increased under the influence of Bacillus subtilis IB-22 more than twice. It was due to the ability of bacteria to produce ABA and reduce the activity of ABA degradation in barley plants. The results obtained in this study indicate that certain bacterial strains are able to increase the level of ABA in plants, compensating for the genetically determined deficiency of this hormone.


2006 ◽  
Vol 189 (5) ◽  
pp. 1565-1572 ◽  
Author(s):  
Venkata Ramana Vepachedu ◽  
Peter Setlow

ABSTRACT The release of dipicolinic acid (DPA) during the germination of Bacillus subtilis spores by the cationic surfactant dodecylamine exhibited a pH optimum of ∼9 and a temperature optimum of 60°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 HgCl2. 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 Ca2+ almost equivalent to those of DPA, and at least one other abundant spore small molecule, glutamic acid, was released in parallel with Ca2+ and DPA. These data indicate that (i) dodecylamine triggers spore germination by opening a channel in the inner membrane for Ca2+-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 Ca2+-DPA and other small molecules during spore germination, perhaps by being a part of a channel in the spore's inner membrane.


2016 ◽  
Vol 4 (4) ◽  
Author(s):  
Daniel R. Reuß ◽  
Andrea Thürmer ◽  
Rolf Daniel ◽  
Wim J. Quax ◽  
Jörg Stülke

Bacillus subtilis ∆6 is a genome-reduced strain that was cured from six prophages and AT-rich islands. This strain is of great interest for biotechnological applications. Here, we announce the full-genome sequence of this strain. Interestingly, the conjugative element ICE Bs 1 has most likely undergone self-excision in B. subtilis ∆6.


1979 ◽  
Vol 179 (2) ◽  
pp. 333-339 ◽  
Author(s):  
A Y Strongin ◽  
D I Gorodetsky ◽  
I A Kuznetsova ◽  
V V Yanonis ◽  
Z T Abramov ◽  
...  

Intracellular serine proteinase was isolated from sporulating cells of Bacillus subtilis Marburg 168 by gramicidin S-Sepharose 4B affinity chromatography. The enzymological characteristics, the amino acid composition and the 19 residues of the N-terminal sequence of the enzyme are reported. The isolated proteinase was closely related to, but not completely identical with, the intracellular serine proteinase of B. subtilis A-50. The divergence between these two intracellular enzymes was less than that between the corresponding extracellular serine proteinases (subtilisins) of types Carlsberg and BPN′!, produced by these bacterial strains. This may be connected with the more strict selection constraints imposed in intracellular enzymes during evolution.


2017 ◽  
Vol 12 (1) ◽  
pp. 255-263 ◽  
Author(s):  
Kanjana Thumanu ◽  
Darawadee Wongchalee ◽  
Mathukorn Sompong ◽  
Piyaporn Phansak ◽  
Toan Le Thanh ◽  
...  

Microbiology ◽  
2008 ◽  
Vol 154 (1) ◽  
pp. 54-63 ◽  
Author(s):  
Kazuo Kobayashi ◽  
Ritsuko Kuwana ◽  
Hiromu Takamatsu

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