scholarly journals Microflora microbiological characteristics of saline soils

2020 ◽  
Vol 175 ◽  
pp. 09010
Author(s):  
Igor Prikhodko ◽  
Artyom Verbitsky ◽  
Stanislav Vladimirov ◽  
Tatyana Safronova

The purpose of current work was isolation of halophilic bacteria from saline lands in some regions of the Krasnodar Territory, after mycological analysis, there followed the study and characterization of microorganisms with further creation on effective biocomplex basis, contributing to restoration of arid and saline irrigated areas. Soil samples were taken from saline lands of the Krasnodar Territory, the salt composition of which was studied in the work process. There were determined total titer of microorganisms and the titer of nitrogen-fixing bacteria on the Corresponding selective media in the samples. Twenty-five pure bacterial cultures were isolated from the samples and its morphophysiological and biochemical properties, as well as its nitrogenfixing activity, were studied. As a result, seven cultures with relatively high nitrogen-fixing activity were selected, as well as resistance to various environmental factors, particularly, to high concentrations of NaCl, рН alkaline values and to sharp temperature drops. After appropriate phylogenetic analysis, selected crops may become a potential target for creating a complex biological fertilizer, contributing to the restoration of dry and saline lands and increase their fertility.

2005 ◽  
Vol 387 (2) ◽  
pp. 541-551 ◽  
Author(s):  
Avinash R. SHENOY ◽  
Nandini P. SREENATH ◽  
Mohana MAHALINGAM ◽  
Sandhya S. VISWESWARIAH

Analysis of the genome sequence of Mycobacterium tuberculosis H37Rv has identified 16 genes that are similar to the mammalian adenylate and guanylate cyclases. Rv1647 was predicted to be an active adenylate cyclase but its position in a phylogenetically distant branch from the other enzymes characterized so far from M. tuberculosis makes it an interestingly divergent nucleotide cyclase to study. In agreement with its divergence at the sequence level from other nucleotide cyclases, the cloning, expression and purification of Rv1647 revealed differences in its biochemical properties from the previously characterized Rv1625c adenylate cyclase. Adenylate cyclase activity of Rv1647 was activated by detergents but was resistant to high concentrations of salt. Mutations of substrate-specifying residues to those present in guanylate cyclases failed to convert the enzyme into a guanylate cyclase, and did not alter its oligomeric status. Orthologues of Rv1647 could be found in M. leprae, M. avium and M. smegmatis. The orthologue from M. leprae (ML1399) was cloned, and the protein was expressed, purified and shown biochemically to be an adenylate cyclase, thus representing the first adenylate cyclase to be described from M. leprae. Importantly, Western-blot analysis of subcellular fractions from M. tuberculosis and M. leprae revealed that the Rv1647 and ML1399 gene products respectively were expressed in these bacteria. Additionally, M. tuberculosis was also found to express the Rv1625c adenylate cyclase, suggesting that multiple adenylate cyclase proteins may be expressed simultaneously in this organism. These results suggest that class III cyclase-like gene products probably have an important role to play in the physiology and perhaps the pathology of these medically important bacteria.


2016 ◽  
Vol 3 (1) ◽  
pp. 43-48 ◽  
Author(s):  
V. Patyka ◽  
L. Butsenko ◽  
L. Pasichnyk

Aim. To validate the suitability of commercial API 20E test-system (bioMerieux) for the identifi cation and characterization of facultative gram-negative phytopathogenic bacterial isolates. Methods. Conventional mi- crobiological methods, API 20E test-system (bioMerieux) according to the manufacturer’s instructions. Re- sults. The identifi cation results for Erwinia amylovora, Pectobacterium carotovorum and Pantoea agglome- rans isolates were derived from the conventional and API 20E test systems, which, were in line with the literature data for these species. The API 20E test-system showed high suitability for P. agglomerans isolates identifi cation. Although not all the species of facultatively anaerobic phytopathogenic bacteria may be identi- fi ed using API 20E test-system, its application will surely allow obtaining reliable data about their physiologi- cal and biochemical properties, valuable for identifi cation of bacteria, in the course of 24 h. Conclusions. The results of tests, obtained for investigated species while using API 20E test-system, and those of conventional microbiological methods coincided. The application of API 20E test-system (bioMerieux) ensures fast obtain- ing of important data, which may be used to identify phytopathogenic bacteria of Erwinia, Pectobacterium, Pantoea genera.


1974 ◽  
Vol 9 (1) ◽  
pp. 250-261
Author(s):  
D.F. Carr ◽  
J. Ganczarczyk

Abstract Activated sludge samples from two Toronto sewage treatment plants were subjected to the extraction of exocellular material by means of 9 different methods suggested for this purpose. Some of those methods, originally developed for pure bacterial cultures, were modified for the application to activated sludge. The amount of exocellular material obtained varied for Lakeview sludges from 0.4 to 3.2% of their dry volatile solids, and for Humber sludges from 0.3 to 5.3%. It has been found that extractions by the use of sulphuric acid, high-speed centrifugation and sodium hydroxide, were not suitable for the studied material. Especially surprising was the ineffectiveness of high-speed centrifugation to yield any measurable amounts of extract. The boiling water extraction is recommended for further studies on activated sludge exocellular material. The material extracted from activated sludge is very complex in nature. Generally more polysaccharide than protein was extracted, but the remaining volatile material may form up to 70% of the dry weight.


Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 677
Author(s):  
John Onolame Unuofin

Laccase is increasingly adopted in diverse industrial and environmental applications, due to its readily accessible requirements for efficient catalytic synthesis and biotransformation of chemicals. However, it is perceived that its industrial production might incur some unfavorable overhead, which leads to expensive market products, and the corresponding negative environmental feedback, due to the use of capital-intensive and precarious chemicals. To this end, this study was designed to evaluate the performance indicators of the valorization of wheat bran by a novel Jb1b laccase and its subsequent application in waste minimization and water management, on a laboratory scale. Optimal Jb1b laccase was produced in submerged fermentation medium containing wheat bran, an agroindustrial residue, through response surface methodology (RSM) algorithm, and was applied in dye decolorization and denim bioscouring, respectively. Results showed that the resultant enzyme manifested unique biochemical properties, such as enhanced tolerance at certain physicochemical conditions, with a residual activity of at least ca. 76%. Furthermore, phenomenally high concentrations of synthetic dyes (0.2% w v−1) were decolorized over 56 h, and a 6 h mediator-supported simultaneous denim bleaching and decolorization of wash effluent was observed. The sustainability of the production and application processes were inferred from the reusability of the fermentation sludge as a potential biofertilizer, with subsequent prospects for the biostimulation and bioaugmentation of contaminated soils, whereas the decolorized water could be adopted for other uses, amongst which horticulture and forestry are typical examples. These phenomena therefore authenticate the favorable environmental feedbacks and overhead realized in this present study.


Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1757
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca ◽  
Antonio Soto-Meca ◽  
Miguel Ángel Martín-Pereira ◽  
María del Carmen García-Onsurbe

This paper presents a novel procedure for the treatment of contaminated water with high concentrations of nitrates, which are considered as one of the main causes of the eutrophication phenomena. For this purpose, magnetic nanoparticles functionalized with silver (Fe3O4@AgNPs) were synthesized and used as an adsorbent of nitrates. Experimental conditions, including the pH, adsorbent and adsorbate dose, temperature and contact time, were analyzed to obtain the highest adsorption efficiency for different concentration of nitrates in water. A maximum removal efficiency of 100% was reached for 2, 5, 10 and 50 mg/L of nitrate at pH = 5, room temperature, and 50, 100, 250 and 500 µL of Fe3O4@AgNPs, respectively. The characterization of the adsorbent, before and after adsorption, was performed by energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. Nitrates can be desorbed, and the adsorbent can be reused using 500 µL of NaOH solution 0.01 M, remaining unchanged for the first three cycles, and exhibiting 90% adsorption efficiency after three regenerations. A deep study on equilibrium isotherms reveals a pH-dependent behavior, characterized by Langmuir and Freundlich models at pH = 5 and pH = 1, respectively. Thermodynamic studies were consistent with physicochemical adsorption for all experiments but showed a change from endothermic to exothermic behavior as the temperature increases. Interference studies of other ions commonly present in water were carried out, enabling this procedure as very selective for nitrate ions. In addition, the method was applied to real samples of seawater, showing its ability to eliminate the total nitrate content in eutrophized waters.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Peixian Bai ◽  
Liyuan Wang ◽  
Kang Wei ◽  
Li Ruan ◽  
Liyun Wu ◽  
...  

Abstract Background Alanine decarboxylase (AlaDC), specifically present in tea plants, is crucial for theanine biosynthesis. Serine decarboxylase (SDC), found in many plants, is a protein most closely related to AlaDC. To investigate whether the new gene AlaDC originate from gene SDC and to determine the biochemical properties of the two proteins from Camellia sinensis, the sequences of CsAlaDC and CsSDC were analyzed and the two proteins were over-expressed, purified, and characterized. Results The results showed that exon-intron structures of AlaDC and SDC were quite similar and the protein sequences, encoded by the two genes, shared a high similarity of 85.1%, revealing that new gene AlaDC originated from SDC by gene duplication. CsAlaDC and CsSDC catalyzed the decarboxylation of alanine and serine, respectively. CsAlaDC and CsSDC exhibited the optimal activities at 45 °C (pH 8.0) and 40 °C (pH 7.0), respectively. CsAlaDC was stable under 30 °C (pH 7.0) and CsSDC was stable under 40 °C (pH 6.0–8.0). The activities of the two enzymes were greatly enhanced by the presence of pyridoxal-5′-phosphate. The specific activity of CsSDC (30,488 IU/mg) was 8.8-fold higher than that of CsAlaDC (3467 IU/mg). Conclusions Comparing to CsAlaDC, its ancestral enzyme CsSDC exhibited a higher specific activity and a better thermal and pH stability, indicating that CsSDC acquired the optimized function after a longer evolutionary period. The biochemical properties of CsAlaDC might offer reference for theanine industrial production.


Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2904
Author(s):  
Margot Gautier ◽  
Cécile Thirant ◽  
Olivier Delattre ◽  
Isabelle Janoueix-Lerosey

Neuroblastoma, a pediatric cancer of the peripheral sympathetic nervous system, is characterized by an important clinical heterogeneity, and high-risk tumors are associated with a poor overall survival. Neuroblastoma cells may present with diverse morphological and biochemical properties in vitro, and seminal observations suggested that interconversion between two phenotypes called N-type and S-type may occur. In 2017, two main studies provided novel insights into these subtypes through the characterization of the transcriptomic and epigenetic landscapes of a panel of neuroblastoma cell lines. In this review, we focus on the available data that define neuroblastoma cell identity and propose to use the term noradrenergic (NOR) and mesenchymal (MES) to refer to these identities. We also address the question of transdifferentiation between both states and suggest that the plasticity between the NOR identity and the MES identity defines a noradrenergic-to-mesenchymal transition, reminiscent of but different from the well-established epithelial-to-mesenchymal transition.


Author(s):  
Mario Vincenzo Russo ◽  
Ivan Notardonato ◽  
Alberto Rosada ◽  
Giuseppe Ianiri ◽  
Pasquale Avino

This paper shows a characterization of the organic and inorganic fraction of river waters (Tiber and Marta) and ores/soil samples collected in the Northern Latium region of Italy for evaluating the anthropogenic/natural source contribution to the environmental pollution of this area. For organic compounds, organochloride volatile compounds in Tiber and Marta rivers were analyzed by two different clean-up methods (i.e., liquid–liquid extraction and static headspace) followed by gas chromatography–electron capture detector (GC-ECD) analysis. The results show very high concentrations of bromoform (up to 1.82 and 3.2 µg L−1 in Tiber and Marta rivers, respectively), due to the presence of greenhouse crops, and of chloroform and tetrachloroethene, due to the presence of handicrafts installations. For the qualitative and quantitative assessment of the inorganic fraction, it is highlighted the use of a nuclear analytical method, instrumental neutron activation analysis, which allows having more information as possible from the sample without performing any chemical-physical pretreatment. The results have evidenced high levels of mercury (mean value 88.6 µg g−1), antimony (77.7 µg g−1), strontium (12,039 µg g−1) and zinc (103 µg g−1), whereas rare earth elements show levels similar to the literature data. Particular consideration is drawn for arsenic (414 µg g−1): the levels found in this paper (ranging between 1 and 5100 µg g−1) explain the high content of such element (as arsenates) in the aquifer, a big issue in this area.


1985 ◽  
Vol 22 (4) ◽  
pp. 375-386 ◽  
Author(s):  
H. C. Wimberly ◽  
D. O. Slauson ◽  
N. R. Neilsen

Antigen-specific challenge of equine leukocytes induced the non-lytic release of a platelet-activating factor in vitro. The equine platelet-activating factor stimulated the release of serotonin from equine platelets in a dose-responsive manner, independent of the presence of cyclo-oxygenase pathway inhibitors such as indomethacin. Rabbit platelets were also responsive to equine platelet-activating factor. The release of equine platelet-activating factor was a rapid reaction with near maximal secretion taking place in 30 seconds. Addition of equine platelet-activating factor to washed equine platelets stimulated platelet aggregation which could not be inhibited by the presence of aspirin or indomethacin. Platelets preincubated with equine platelet-activating factor became specifically desensitized to equine platelet-activating factor while remaining responsive to other platelet stimuli such as collagen and epinephrine. The following biochemical properties of equine platelet-activating factor are identical to those properties of 1-0-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (AGEPC): stability upon exposure to air and acid; loss of functional activity after basecatalyzed methanolysis with subsequent acylation that returned all functional activity; and identical relative mobilities on silica gel G plates developed with chloroform:methanol:water (65:35:6, volume/volume). The combined functional and biochemical characteristics of equine platelet-activating factor strongly suggest identity between this naturally occurring, immunologically derived equine factor and AGEPC.


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