scholarly journals The processes of lipid peroxidation in the cells of Chlorobium limicola IMV K-8 under the influence of copper (II) sulphate

2015 ◽  
Vol 24 (1) ◽  
pp. 72-77 ◽  
Author(s):  
T. B. Segin ◽  
S. О. Hnatush ◽  
M. B. Gorishniy
Keyword(s):  
Lipid Peroxidation ◽  
Free Radical ◽  
Ammonium Thiocyanate ◽  
Biochemical Properties ◽  
Conjugated Dienes ◽  
Lipid Hydroperoxides ◽  
Chlorobium Limicola ◽  
Bacterial Membranes ◽  
Physiological And Biochemical ◽  
Physiological And Biochemical Properties

The effect of stressors, including heavy metal ions such as Cu2+, promotes activation of free radical processes in the cells of microorganisms, which causes changes in their physiological and biochemical properties and the structure of bacterial membranes. The aim of this work was to assess the influence of copper (II) sulphate on intensity of lipid peroxidation (LPO) of Chlorobium limicola IMV K-8 by measuring the content of primary (conjugated dienes and lipid hydroperoxides) and secondary lipid peroxidation products (TBA-reactive products). Microorganisms were cultivated at a temperature of 28 °C in GSB cultivation medium with exposure to light of wavelength 700–800 nm and intensity 40 lux. A suspension of C. limicola ІМV К-8 cells in the phase of exponential growth was treated for one hour with metal salt solution in concentrations 0.05–0.50 mM for investigation of the influence of copper (II) sulphate on its physiological and biochemical properties. The control samples did not contain any copper (II) sulphate. Biomass was determined by turbidity of diluted cell suspension by application of photoelectric colorimeter KFK-3. A mixture of n-heptane and isopropyl alcohol was added into cell-free extract for conjugated dienes determination. The samples were incubated at room temperature and centrifuged. Water was added into the supernatant and the samples were stirred. Ethanol was added to the heptanes phase and adsorption was measured at 233 nm. The content of lipid hydroperoxides was determined by a method based on protein precipitation by trichloroacetic acid followed by addition of ammonium thiocyanate. The concentration of TBA-reactive products in the cell-free extracts was determined by color reaction with malondialdehyde and thiobarbituric acid exposed to high temperature and acidity of the medium, which causes formation of trimetinic adduct with maximal absorption at 532 nm. It was shown that when CuSO4 was added to the incubation medium the content of conjugated dienes and lipid hydroperoxides increased with the enhancement of salt concentration. However, its value decreased by the seventh and eighth days of cultivation. The content of TBA-reactive products under the influence of copper (II) sulphate varied depending on the duration of cultivation and concentration of the metal. Its highest quantity was observed on the eighth day of cultivation. Thus it was determined that under the influence of CuSO4 the content of conjugated dienes, lipid hydroperoxides and TBA-reactive products increases. This indicates the increased activity of lipid peroxidation processes and the free radical chain reaction damage mechanism to lipids under these conditions.

scholarly journals Active Antibiotics Production by Actinomycetes Indigenous To Saudi Arabia Soils

2021 ◽  
Vol 11 (6) ◽  
pp. 20-29
Author(s):  
Fetoon M ◽  
helaiwi Alk ◽  
Ismet Ara ◽  
Nadine Moubayed
Keyword(s):  
Saudi Arabia ◽  
Biochemical Properties ◽  
Soil Samples ◽  
Fungal Strain ◽  
Pathogenic Microorganisms ◽  
Bacterial Strains ◽  
Desert Soils ◽  
Growth Environment ◽  
Physiological And Biochemical ◽  
Physiological And Biochemical Properties

Streptomyces are the most popular among the Actinomycetes groups and found in soils worldwide. They form an important part of the soil ecology within the Actinomycetales order. Streptomyces are diverse as secondary antibiotic metabolites such as Novobiocin, Amphotericin, Vancomycin, Neomycin, Gentamicin, Chloramphenicol, Tetracycline, Erythromycin and Nystatin. Thus, the current study was aimed to isolate, identify and assess the active antibiotic metabolites produced by different actinomyces sp. found in Saudi Arabian soils. Six samples were collected from desert soils of the Al Thumamah area and analyzed using GS-MS. Scanning Electron Microscopy was used to identify the bacterial strains along with their antibiotic metabolites effectiveness of secondary metabolites (antibiotics) against different Gram-positive (Bacillus subtilis, Staphylococcus aureus), negative pathogens (Pseudomonas aeruginosa, Escherichia coli, Salmonella suis, and Shigella sonnei) as well as the fungal strain Candida albicans was investigated. Thirty active bacterial (F1-30) strains were isolated from the soil samples and the strains F3, F7, F22, F30 have white, gray, pink, yellow and red colours respectively. Only ten strains (F13, F14, F15, F16, FI7, F18, F19, F20, F21, and F22) were found to have antimicrobial activity against at least one pathogen. The optimum growth environment was pH 4-10, temperature (300C), and NaCl (7% w/v) concentration. According to our findings, the extreme desert environment of Al Thumamah from Saudi Arabia is rich in its actinobacterial population with diverse colouring groups and various physiological and biochemical properties. This shows it’s capability of generating secondary metabolite elements that could inhibit pathogenic microorganisms.

scholarly journals Physiology and Nutrition of Treponema primitia, an H2/ CO2-Acetogenic Spirochete from Termite Hindguts

2004 ◽  
Vol 70 (3) ◽  
pp. 1307-1314 ◽  
Author(s):  
Joseph R. Graber ◽  
John A. Breznak
Keyword(s):  
Nadh Oxidase ◽  
Natural Habitat ◽  
Biochemical Properties ◽  
Organic Substrates ◽  
Growth And Survival ◽  
Cell Extracts ◽  
Termite Hindgut ◽  
Physiological And Biochemical ◽  
Physiological And Biochemical Properties

ABSTRACT Treponema primitia strains ZAS-1 and ZAS-2, the first spirochetes to be isolated from termite hindguts (J. R. Leadbetter, T. M. Schmidt, J. R. Graber, and J. A. Breznak, Science 283:686-689, 1999), were examined for nutritional, physiological, and biochemical properties relevant to growth and survival in their natural habitat. In addition to using H2 plus CO2 as substrates, these strains were capable of homoacetogenic growth on mono- and disaccharides and (in the case of ZAS-2) methoxylated benzenoids. Cells were also capable of mixotrophic growth (i.e., simultaneous utilization of H2 and organic substrates). Cell extracts of T. primitia possessed enzyme activities of the Wood/Ljungdahl (acetyl coenzyme A) pathway of acetogenesis, including tetrahydrofolate-dependent enzymes of the methyl group-forming branch. However, a folate compound was required in the medium for growth. ZAS-1 and ZAS-2 growing on H2 plus CO2 displayed H2 thresholds of 650 and 490 ppmv, respectively. Anoxic cultures of ZAS-1 and ZAS-2 maintained growth after the addition of as much as 0.5% (vol/vol) O2 to the headspace atmosphere. Cell extracts exhibited NADH and NADPH peroxidase and NADH oxidase activities but neither catalase nor superoxide dismutase activity. Results indicate that (i) T. primitia is able to exploit a variety of substrates derived from the food of its termite hosts and in so doing contributes to termite nutrition via acetogenesis, (ii) in situ growth of T. primitia is likely dependent on secretion of a folate compound(s) by other members of the gut microbiota, and (iii) cells possess enzymatic adaptations to oxidative stress, which is likely to be encountered in peripheral regions of the termite hindgut.

scholarly journals Emended descriptions of the genus Lewinella and of Lewinella cohaerens, Lewinella nigricans and Lewinella persica, and description of Lewinella lutea sp. nov. and Lewinella marina sp. nov.

2007 ◽  
Vol 57 (12) ◽  
pp. 2946-2951 ◽  
Author(s):  
Shams Tabrez Khan ◽  
Yukiyo Fukunaga ◽  
Yasuyoshi Nakagawa ◽  
Shigeaki Harayama
Keyword(s):  
Type Strain ◽  
Biochemical Properties ◽  
Rrna Gene ◽  
16S Rrna Gene Sequences ◽  
The Pacific ◽  
Marine Sediment Sample ◽  
Pacific Coast Of Japan ◽  
Type Strains ◽  
Physiological And Biochemical ◽  
Physiological And Biochemical Properties

Two strains, MKG-38T and FYK2402M69T, were isolated from a marine sediment sample and a sea snail, respectively, both collected on the Pacific coast of Japan. Phylogeny of these new isolates based on 16S rRNA gene sequences indicated that they are members of the genus Lewinella. Morphological, physiological and biochemical properties of these two isolates, together with the type strains of the three previously described species of the genus Lewinella, were characterized. The new isolates were Gram-negative, aerobic, rod-shaped, chemo-organotrophic and able to degrade starch and CM-cellulose. A comparative polyphasic study showed that these two isolates represent two novel species of the genus Lewinella, for which the names Lewinella marina sp. nov. (type strain, MKG-38T=NBRC 102633T=NCIMB 14312T) and Lewinella lutea sp. nov. (type strain, FYK2402M69T=NBRC 102634T=NCIMB 14313T) are proposed. Emended descriptions of the genus Lewinella (Sly et al. 1998) and of Lewinella cohaerens, Lewinella nigricans and Lewinella persica are also proposed.

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