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Bacillus licheniformis
About: Bacillus licheniformis is a research topic. Over the lifetime, 4760 publications have been published within this topic receiving 90430 citations.
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TL;DR: Using the bacterium Bacillus licheniformis, the biosynthesis of silver nanoparticles was investigated and the formation of well-dispersedsilver nanoparticles of 50 nm was revealed, and the presence of silver was confirmed by EDX analysis.
841 citations
TL;DR: The production of organic acids by these mangrove rhizosphere microorganisms as a possible mechanism involved in the solubilization of insoluble calcium phosphate is proposed.
Abstract: The phosphate-solubilizing potential of the rhizosphere microbial community in mangroves was de- monstrated when culture media supplemented with in- soluble, tribasic calcium phosphate, and incubated with roots of black (Avicennia germinans L.) and white (La- guncularia racemosa (L.) Gaertn.) mangrove became transparent after a few days of incubation. Thirteen phosphate-solubilizing bacterial strains were isolated from the rhizosphere of both species of mangroves: Ba- cillus amyloliquefaciens, Bacillus licheniformis, Bacillus atrophaeus, Paenibacillus macerans, Vibrio proteolyti- cus, Xanthobacter agilis, Enterobacter aerogenes, Ente- robacter taylorae, Enterobacter asburiae, Kluyvera cryo- crescens, Pseudomonas stutzeri, and Chryseomonas lu- teola. One bacterial isolate could not be identified. The rhizosphere of black mangroves also yielded the fungus Aspergillus niger. The phosphate-solubilizing activity of the isolates was first qualitatively evaluated by the for- mation of halos (clear zones) around the colonies grow- ing on solid medium containing tribasic calcium phos- phate as a sole phosphorus source. Spectrophotometric quantification of phosphate solubilization showed that all bacterial species and A. niger solubilized insoluble phosphate well in a liquid medium, and that V. proteo- lyticus was the most active solubilizing species among the bacteria. Gas chromatographic analyses of cell-free spent culture medium from the various bacteria de- monstrated the presence of 11 identified, and several unidentified, volatile and nonvolatile organic acids. Those most commonly produced by different species were lactic, succinic, isovaleric, isobutyric, and acetic acids. Most of the bacterial species produced more than one organic acid whereas A. niger produced only suc- cinic acid. We propose the production of organic acids by these mangrove rhizosphere microorganisms as a possible mechanism involved in the solubilization of in- soluble calcium phosphate.
609 citations
TL;DR: The data indicated that culture of both bacteria accumulate bioactive C 19 -gibberellins in relative high amounts and that these GAs appear to be physiologically active in the host plant.
Abstract: The plant-growth-promoting rhizobacteria (PGPR), Bacillus pumilus and Bacillus licheniformis, isolated from the rhizosphere of alder (Alnus glutinosa [L.] Gaertn.) have a strong growth-promoting activity. Bioassay data showed that the dwarf phenotype induced in alder seedlings by paclobutrazol (an inhibitor of gibberellin [GA] biosynthesis) was effectively reversed by applications of extracts from media incubated with both bacteria and also by exogenous GA 3 , Full-scan gas chromatography-mass spectrometry analyses on extracts of these media showed the presence of GA 1 , GA 3 , GA 4 and GA 20 , in addition to the isomers 3-epi-GA 1 and iso-GA 3 . Isotope dilution analysis indicated that epi-GA 1 was an artefact. Likewise, iso-GA 3 is also probably an artifact spontaneously formed during extraction and/or analysis. In both culture media, GA 1 was present in higher concentrations (130-150 ng ml -1 ) than GA 3 (50-60 ng ml -1 ), GA 4 (8-12 ng ml -1 ) and GAS (2-3 ng ml -1 ). The data indicated that culture of both bacteria accumulate bioactive C 19 -gibberellins in relative high amounts and that these GAs appear to be physiologically active in the host plant. The evidence suggests that the promotion of stem elongation induced by the PGPR could be mediated by bacterial GAs.
598 citations
TL;DR: Drought stress affected growth of isolates as indicated by increased intracellular free amino acids, proline, total soluble sugars, and exopolysaccharides, while inoculated maize seedlings showed physiological response that could alleviate drought stress negative effects.
Abstract: In present study Bacillus spp. screened for drought tolerance could tolerate minimal water potential (-0.73 MPa) were evaluated for plant growth promoting properties at –0.73 MPa. Drought stress affected growth of isolates as indicated by increased intracellular free amino acids, proline, total soluble sugars, and exopolysaccharides. Drought-tolerant Bacillus spp. HYD-B17, HYTAPB18, HYDGRFB19, BKB30, RMPB44 identified as Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus thuringiensis, Paenibacillus favisporus, Bacillus subtilis based on 16S rDNA gene sequence were used to study the effect of inoculation on growth, osmolytes, antioxidant status. Inoculation increased plant biomass, relative water content, leaf water potential, root adhering soil/root tissue ratio, aggregate stability, decreasing leaf water loss. Bacillus spp. effect on osmoregulation increased proline, sugars, free amino acids and decreased electrolyte leakage. Inoculation reduced the activity of antioxidant enzymes asc...
455 citations
TL;DR: Purified lichenysin A decreases the surface tension of water from 72 mN/m to 28 mN /liter and achieves the critical micelle concentration with as little as 12 mg/liter, characterizing the product as a powerful surface-active agent that compares favorably to others surfactants.
Abstract: Strain BAS50, isolated from a petroleum reservoir at a depth of 1,500 m and identified as Bacillus licheniformis, grew and produced a lipopeptide surfactant when cultured on a variety of substrates at salinities of up to 13% NaCl. Surfactant production occurred both aerobically and anaerobically and was optimal at 5% NaCl and temperatures between 35 and 45 degrees C. The biosurfactant, termed lichenysin A, was purified and chemically characterized. A tentative structure and composition for the surfactant are described. Lichenysin A is a mixture of lipopeptides, with the major components ranging in size from 1,006 to 1,034 Da. The lipid moiety contains a mixture of 14 linear and branched beta-hydroxy fatty acids ranging in size from C12 to C17. There are seven amino acids per molecule. The peptide moiety is composed of the following amino acids: glutamic acid as the N-terminal amino acid, asparagine, valine, leucine, and isoleucine as the C-terminal amino acid, at a ratio of 1.1:1.1:1.0:2.8:1.0, respectively. Purified lichenysin A decreases the surface tension of water from 72 mN/m to 28 mN/m and achieves the critical micelle concentration with as little as 12 mg/liter, characterizing the product as a powerful surface-active agent that compares favorably to others surfactants. The antibacterial activity of lichenysin A has been demonstrated.
440 citations