Metabolism of o-phthalic acid by different gram-negative and gram-positive soil bacteria

1976 ◽  
Vol 109 (1-2) ◽  
pp. 109-114 ◽  
Author(s):  
Gabriele Engelhardt ◽  
P. R. Walln�fer ◽  
H. G. Rast ◽  
F. Fiedler
Keyword(s):  
Phthalic Acid ◽  
Soil Bacteria ◽  
Gram Positive ◽  
Gram Negative

scholarly journals Microbial hitchhiking: how Streptomyces spores are transported by motile soil bacteria

2021 ◽  
Author(s):  
Alise R. Muok ◽  
Dennis Claessen ◽  
Ariane Briegel
Keyword(s):  
Microbial Communities ◽  
Soil Bacteria ◽  
Plant Roots ◽  
Structural Proteins ◽  
Plant Tissues ◽  
Gram Negative Bacteria ◽  
Spore Coat ◽  
Gram Positive ◽  
Gram Negative

AbstractStreptomycetes are sessile bacteria that produce metabolites that impact the behavior of microbial communities. Emerging studies have demonstrated that Streptomyces spores are distributed through various mechanisms, but it remains unclear how spores are transported to their preferred microenvironments, such as plant roots. Here, we show that Streptomyces spores are capable of utilizing the motility machinery of other soil bacteria. Motility assays and microscopy studies reveal that Streptomyces spores are transported to plant tissues by interacting directly with the flagella of both gram-positive and gram-negative bacteria. Genetics experiments demonstrate that this form of motility is facilitated by structural proteins on the spore coat. These results demonstrate that nonmotile bacteria are capable of utilizing the motility machinery of other microbes to complete necessary stages of their lifecycle.

MORPHOLOGICAL AND PHYSIOLOGICAL GROUPS OF SOIL BACTERIA FROM THE ROOTS OF BARLEY AND OATS

1956 ◽  
Vol 2 (5) ◽  
pp. 473-481 ◽  
Author(s):  
H. DeL. King ◽  
R. H. Wallace
Keyword(s):  
Soil Bacteria ◽  
Sandy Loam ◽  
The Other ◽  
Physiological Characteristics ◽  
Gram Positive ◽  
Gram Negative ◽  
Rhizosphere Soils ◽  
Reducing Bacteria ◽  
Nitrate Reducing Bacteria ◽  
Percentage Incidence

Morphological and physiological characteristics were studied of more than 2400 stock-cultures of bacteria isolated from rhizosphere soils of barley and oats, and from control soils. Gram-positive rods were proportionately more numerous in control soils than in rhizosphere soils; this difference was greater with oats than with barley. The proportion of Gram-negative rods was greater in rhizosphere soils than in controls but not more so for one crop than the other. Gram-positive rods replaced a significant portion of Gram-negative rods in soils of the mature barley plants. The only significant increase in percentage incidence of physiological groups in rhizosphere soils was in regard to nitrate-reducing bacteria of the young oats plants. On the other hand there were significantly smaller percentages for starch-hydrolyzing bacteria and gelatin liquefiers in oats rhizospheres than in the controls. There were not any significant differences between rhizospheres and controls with regard to physiological groups from the barley plants. It is concluded that the proportional incidences of some physiological groups of soil bacteria are not greatly increased, but in some instances are decreased, by the presence of barley or oat roots growing in Chicot sandy loam.

scholarly journals Microbial piggy-back: how Streptomyces spores are transported by motile soil bacteria

2020 ◽  
Author(s):  
Alise R. Muok ◽  
Dennis Claessen ◽  
Ariane Briegel
Keyword(s):  
Microbial Communities ◽  
Soil Bacteria ◽  
Plant Health ◽  
Plant Roots ◽  
Structural Proteins ◽  
Plant Tissues ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Mode Of Transport

AbstractStreptomycetes are sessile, soil-dwelling bacteria that produce diverse metabolites that impact plant health and the behavior of microbial communities. Emerging studies have demonstrated that Streptomyces spores are distributed through a variety of mechanisms, but it remains unclear how spores are transported to their preferred micro-environments, such as plant roots. Here, we show that Streptomyces spores are capable of utilizing the motility machinery of other soil bacteria and are transported on the centimeter scale. Motility assays and microscopy studies reveal that Streptomyces spores are transported to plant tissues by interacting directly with the flagella of both gram-positive and gram-negative bacteria. Genetics experiments demonstrate that this form of motility, called piggy-backing, is facilitated by conserved structural proteins present on the surface of Streptomyces spores. These results demonstrate that non-motile bacteria are capable of utilizing the motility machinery of other microbes to complete necessary stages of their lifecycle, and that this mode of transport may be ubiquitous in nature.

Differentiation of Arthrobacter soil isolates and named strains from other bacteria by reactions on dye-containing media

1975 ◽  
Vol 21 (5) ◽  
pp. 688-693 ◽  
Author(s):  
Charles Hagedorn ◽  
John G. Holt
Keyword(s):  
Soil Bacteria ◽  
Selective Growth ◽  
The Other ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Bacterial Cultures ◽  
Dye Absorption ◽  
The Common

Twenty-five gram-negative and 62 gram-positive bacterial cultures, of which 37 were arthrobacters, were tested, using a multipoint inoculation device, for responses on varying concentrations of 35 dyes. Both selective (growth vs. no growth) and differential (dye absorption) responses were obtained. It was possible to differentiate the arthrobacters from the other gram-positive bacteria tested as well as to distinguish separately each Arthrobacter -named strain. The results indicated that dyes have a greater potential for use in selective and differential media than has been presently realized; and the possibility of using dye-reactions as features in taxonomic schemes to differentiate rapidly many of the common genera of soil bacteria is discussed.

Microanatomy of the Periplasm of Bacillus Licheniformis

1971 ◽  
Vol 29 ◽  
pp. 262-263
Author(s):  
B.K. Ghosh
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Bacillus Licheniformis ◽  
External Environment ◽  
Permeability Barrier ◽  
Periplasmic Space ◽  
Modified Technique ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.

Rapid demonstration of septic or infectious arthritis due to Gram-negative bacteria

1992 ◽  
Vol 50 (1) ◽  
pp. 686-687
Author(s):  
Jacob S. Hanker ◽  
Paul R. Gross ◽  
Beverly L. Giammara
Keyword(s):  
Chronic Arthritis ◽  
Blood Cultures ◽  
Gram Negative Bacteria ◽  
Infectious Arthritis ◽  
Bacterial Arthritis ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Blood cultures are positive in approximately only 50 per cent of the patients with nongonococcal bacterial infectious arthritis and about 20 per cent of those with gonococcal arthritis. But the concept that gram-negative bacteria could be involved even in chronic arthritis is well-supported. Gram stains are more definitive in staphylococcal arthritis caused by gram-positive bacteria than in bacterial arthritis due to gram-negative bacteria. In the latter situation where gram-negative bacilli are the problem, Gram stains are helpful for 50% of the patients; they are only helpful for 25% of the patients, however, where gram-negative gonococci are the problem. In arthritis due to gram-positive Staphylococci. Gramstained smears are positive for 75% of the patients.

In-vitro Antioxidant and Antibacterial Activity of Methanolic Extract of Shorea robusta Gaertn. F. Resin

2016 ◽  
Vol 6 (4) ◽  
pp. 68
Author(s):  
Sushma Vashisht ◽  
Manish Pal Singh ◽  
Viney Chawla
Keyword(s):  
Antibacterial Activity ◽  
Methanolic Extract ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Disc Diffusion ◽  
Gram Positive ◽  
Gram Negative ◽  
Shorea Robusta ◽  
Dose Dependent ◽  
Resin Extract

The methanolic extract of the resin of Shorea robusta was subjected to investigate its antioxidant and antibacterial properties its utility in free radical mediated diseases including diabetic, cardiovascular, cancer etc. The methanol extract of the resin was tested for antioxidant activity using scavenging activity of DPPH (1,1-diphenyl-2-picrylhydrazil) radical method, reducing power by FeCl3 and antibacterial activity against gram positive and gram negative bacteria using disc diffusion method. The phytochemical screening considered the presence of triterpenoids, tannins and flavoniods. Overall, the plant extract is a source of natural antioxidants which might be helpful in preventing the progress of various oxidative stress mediated diseases including aging. The half inhibition concentration (IC50) of resin extract of Shorea robusta and ascorbic acid were 35.60 µg/ml and 31.91 µg/ml respectively. The resin extract exhibit a significant dose dependent inhibition of DPPH activity. Antibacterial activity was observed against gram positive and gram negative bacteria in dose dependent manner.Key Words: Shorea robusta, antioxidant, antibacterial, Disc-diffusion, DPPH.

Antibacterial activity of magnesium oxide nanoparticles prepared by Calcination method

2019 ◽  
Vol 10 (03) ◽  
Author(s):  
Elaf Ayad Kadhem ◽  
Miaad Hamzah Zghair ◽  
Sarah , Hussam H. Tizkam, Shoeb Alahmad Salih Mahdi ◽  
Hussam H. Tizkam ◽  
Shoeb Alahmad
Keyword(s):  
Antibacterial Activity ◽  
Magnesium Oxide ◽  
Diffusion Method ◽  
Oxide Nanoparticles ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Magnesium Oxide Nanoparticles ◽  
Agar Disc

magnesium oxide nanoparticles (MgO NPs) were prepared by simple wet chemical method using different calcination temperatures. The prepared NPs were characterized by Electrostatic Discharge (ESD), Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). It demonstrates sharp intensive peak with the increase of crystallinty and increase of the size with varying morphologies with respect to increase of calcination temperature. Antibacterial studies were done on gram negative bacteria (E.coli) and gram positive bacteria (S.aureus) by agar disc diffusion method. The zones of inhibitions were found larger for gram positive bacteria than gram negative bacteria, this mean, antibacterial MgO NPs activity more active on gram positive bacteria than gram negative bacteria because of the structural differences. It was found that antibacterial activity of MgO NPs was found it has directly proportional with their concentration.

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